bluuebunny/crossref_metadata_2025 huggingface dataset:
Beyond muscles: role of intramuscular connective tissue elasticity and passive stiffness in octopus arm muscle function
Authors: Di Clemente Alessio , Maiole Federica , Bornia Irene , Zullo Letizia
Published: November 2021

The octopus arm is a ‘one of a kind’ muscular hydrostat, as demonstrated by its high maneuverability and complexity of motions. It is composed of a complex array of muscles and intramuscular connective tissue, allowing force and shape production. In this study, we investigated the organization of the intramuscular elastic fibers in two main muscles composing the arm bulk: the longitudinal (L) and the transverse (T) muscles. We assessed their contribution to the muscles’ passive elasticity and stiffness and inferred their possible roles in limb deformation. First, we performed confocal imaging of whole-arm samples and provided evidence of a muscle-specific organization of elastic fibers (more chaotic and less coiled in T than in L). We next showed that in an arm at rest, L muscles are maintained under 20% compression and T muscles under 30% stretching. Hence, tensional stresses are inherently present in the arm and affect the strain of elastic fibers. Because connective tissue in muscles is used to transmit stress and store elastic energy, we investigated the contribution of elastic fibers to passive forces using step-stretch and sinusoidal length-change protocols. We observed a higher viscoelasticity of L and a higher stiffness of T muscles, in line with their elastic fiber configurations. This suggests that L might be involved in energy storage and damping, whereas T is involved in posture maintenance and resistance to deformation. The elastic fiber configuration thus supports the specific role of muscles during movement and may contribute to the mechanics, energetics and control of arm motion.
Jumping in lantern bugs (Hemiptera, Fulgoridae)
Authors: Burrows M. , Ghosh A. , Sutton G. P. , Yeshwanth H. M. , Rogers S. M. , Sane S. P.
Published: November 2021

Lantern bugs are amongst the largest of the jumping hemipteran bugs, with body lengths reaching 44 mm and masses reaching 0.7 g. They are up to 600 times heavier than smaller hemipterans that jump powerfully using catapult mechanisms to store energy. Does a similar mechanism also propel jumping in these much larger insects? The jumping performance of two species of lantern bugs (Hemiptera, Auchenorrhyncha, family Fulgoridae) from India and Malaysia was therefore analysed from high-speed videos. The kinematics showed that jumps were propelled by rapid and synchronous movements of both hind legs, with their trochantera moving first. The hind legs were 20–40% longer than the front legs, which was attributable to longer tibiae. It took 5–6 ms to accelerate to take-off velocities reaching 4.65 m s−1 in the best jumps by female Kalidasa lanata. During these jumps, adults experienced an acceleration of 77 g, required an energy expenditure of 4800 μJ and a power output of 900 mW, and exerted a force of 400 mN. The required power output of the thoracic jumping muscles was 21,000 W kg−1, 40 times greater than the maximum active contractile limit of muscle. Such a jumping performance therefore required a power amplification mechanism with energy storage in advance of the movement, as in their smaller relatives. These large lantern bugs are near isometrically scaled-up versions of their smaller relatives, still achieve comparable, if not higher, take-off velocities, and outperform other large jumping insects such as grasshoppers.
The nation loves the householder, but also loves the bandit
Authors: Μπατάλας Αχιλλεύς
Published: November 2021

Η παρούσα διατριβή επιχειρεί να περιγράψει και να αιτιολογήσει διαδικασίες εθνικής οικοδόμησης δια μέσω μιας λεπτομερούς διερεύνησης των δυνάμεων και των παραγόντων που συμμετείχαν στη μετατροπή κλεφτών-αρματολών σε ελληνικούς εθνικούς ήρωες κατά την περίοδο 1750-1862. Ο γενικός στόχος της διατριβής είναι να συνεισφέρει στον υπάρχοντα διάλογο σχετικά με τα έθνη και τον εθνικισμό, επιχειρώντας να γεφυρώσει το χάσμα μεταξύ των νεωτεριστικών και εθνοσυμβολικών προσεγγίσεων των σχετικών φαινομένων. Αυτός ο στόχος έχει επιτευχθεί με την διαμόρφωση ενός αναλυτικού πλαισίου που βασίζεται σε τέσσερις γενικές προτάσεις και ταυτόχρονα επεξηγώντας πως αυτές μπορούν να συμβάλουν σε πιο βελτιωμένες και ευαίσθητες, στο ιστορικό πλαίσιο, αναλύσεις περί απόπειρας οικοδόμησης του έθνους (δηλαδή, τα έθνη και ο εθνικισμός είναι συστατικά στοιχεία της νεωτερικότητας, αποτελούν κατασκευασμένες ή επινοημένες μορφές ανθρώπινης οργάνωσης· γίνεται λόγος για τη σημασία του εθνοτικού-πολιτισμικού υλικού στη διαμόρφωση των εθνών· για την εγγενώς ενδεχόμενη και αμφιλεγόμενη φύση τέτοιων διαδικασιών). Τέλος, η διατριβή τονίζει ότι οι ακόλουθοι παράγοντες είναι απαραίτητοι, αλλά όχι επαρκείς, για επιτυχημένα εγχειρήματα εθνικής οικοδόμησης: η σχέση μεταξύ της εθνικής ταυτότητας ή του μύθου που διαδίδεται καθώς και των επικρατουσών κοσμοθεωριών του στοχευμένου πληθυσμού· η σύσταση ανθεκτικών και αποτελεσματικών μηχανισμών εθνικής συγκρότησης και τέλος η συνοδευόμενη θεσμοθέτηση του συγκεκριμένου μύθου ή ταυτότητας.
[18F]Fluoromethylcholine PET/CT for CNS lymphoma assessment: a new tool
Authors: Marshall Kirsty , Sharma Bhupinder , Millard Thomas , Chhabda Sahil , Sheikh Fayed , Guilhem Emily , Cunningham Joel , Du Yong , Alexander Emma , Cunningham David , Attygalle Ayoma , Chau Ian , Iyengar Sunil , El-Sharkawi Dima
Published: November 2021

Background

Central nervous system (CNS) lymphomas are a rare subset of lymphoma, which are associated with a poor outcome. The gold standard for CNS imaging is with gadolinium-enhanced magnetic resonance imaging (MRI); however, there are a number of limitations, including some patients with small persistent abnormalities from scarring due to focal haemorrhage or from a previous biopsy, which can be difficult to discern from residual tumour. [18F]Fluoromethylcholine positron emission tomography–computed tomography (FCH-PET/CT) uses an analogue of choline, which due to the upregulation of choline kinase in tumour cells, allows increased uptake of FCH. As there is minimal background grey matter uptake of FCH, FCH-PET/CT can be used in CNS imaging and provide a useful tool for response assessment.

Methods

This is a cohort study, where we identified 40 patients with a diagnosis of primary or secondary CNS lymphoma between 1st November 2011 and 10th October 2019.

Results

26 of the 40 patients (65%) had concordant results. Of the discordant results, 11 out of 14 had partial response (PR) on MRI but showed a metabolic complete response (mCR) on FCH-PET. The overall response rates (ORR) were similar between the two modalities (90% for MRI versus 95% with FCT-PET/CT).

Conclusion

We conclude that FCH-PET/CT is a reasonable alternative mode of imaging to gadolinium-enhanced MRI brain imaging, providing a new tool for assessment of CNS lymphoma.
Adapting the Swedish Experience of Corporate Culture Management to Russian Branches on the Example of «Daniel Wellington LLC»
Authors: Hoholeva E. , Zaharova E.
Published: November 2021

The corporate culture of an organization plays an important role in the personnel management system. Its influence is especially important in branches that operate in another country. The article examines the Swedish experience of corporate culture management and the possibility of its adaptation to Russian branches on the example of the organization "Daniel Wellington". The article contains a study to identify the difficulties in applying the corporate culture of the brand of the founding country to the Russian reality. The reasons that can hinder the implementation are identified, and the readiness of the Russian brand staff for possible changes is determined. The Russian and Swedish corporate cultures of the brand are compared. The current attitude of employees to the use of online platforms used for the exchange of experience is revealed.
PROCESS MODELLING THE CURE OF BISPHENOL-A EPOXY/JEFFAMINE SYSTEM USING ICME
Authors: DESHPANDE P. P. , SHAH, S. , PATIL, S. U. , OLAYA M. , ODEGARD G. M. , MAIARU M.
Published: November 2021

The prediction of thermo-mechanical properties of a thermoset resin at different stages of cure is a complex process. An Integrated Computational Material Engineering (ICME) approach is used to predict the properties of a EPON828/Jeffamine D230 system. The proposed framework integrates two length scales - nano and microscale. Molecular Dynamics (MD) is used to predict the volume shrinkage and mechanical properties of the epoxy resin as a function of the progressing crosslink density at room temperature using the Reactive Interface forcefield (IFF-R). The predicted resin properties show good agreement with the literature, proving that IFF-R can be reliably used for this purpose. Once characterized, the predicted properties are used to further predict the effects of cure shrinkage and property transformation on the bulk-level composite residual stresses. P. P. DESHPANDE
USING DATA SCIENCE TO EVALUATE NANO-REINFORCED EPOXY SURFACES
Authors: THEIM JONATHAN , COLE DANIEL P. , DUBEY UTKARSH , SRIVASTAVA ASHUTOSH , ASHRAF CHOWDHURY , HENRY, TODD C. , BAKIS CHARLES E. , YASHISTH ANIRUDDH
Published: November 2021

Toughened composites reinforced with nanofillers show improved mechanical performance such as increased abrasion resistance, fracture toughness, and fracture energy. The degree of these improvements is influenced by the degree of dispersion of the nanofillers which can be analyzed using force microscopy (AFM), a technique that allows for mapping the local height and elastic modulus of a surface. However, current AFM apparatuses can only measure a narrow range of moduli according to the type of tip, which complicates the full-field measurement of moduli in nanocomposites with nanosilica (~72 GPa) embedded in epoxy (0.1 – 5 GPa). Moreover, height mapping can only visualize filler particles exposed at the surface. These limitations make it challenging to determine the 3D location of nanoparticles near the surface of a composite. To overcome these limitations of conventional AFM, we used a combination of data science, micromechanics, and experimental data from AFM to locate the centroidal position of nanosilica (NS) particles relative to the surrounding epoxy surface. Using finite element simulations, a theoretical dataset of modulus values as a function of particle position relative to the epoxy surface was created as a training set. Bayesian optimization determines the “best” particle position that results in minimum error between simulated and experimental modulus contours. The algorithm returns the 3D position of the fully or partially embedded NS particle relative to the epoxy surface. The algorithm has shown the ability to partially produce simulated modulus contours that resemble the experimental modulus contours.
MECHANICAL BEHAVIOR OF ADHESIVELY-BONDED JOINTS UNDER HIGH LOADING RATES
Authors: ERCAN MEHMET EMIN , KADIOGLU FERHAT
Published: November 2021

This work aims to investigate the dynamic behavior of adhesively-bonded Single Lap Joints (SLJs) under ballistic conditions. For this purpose, the joints with clamped-clamped boundary conditions were modelled using a Finite Element Method (FEM) via ABAQUS package program. The numerical model is based on the joint subjected to a projectile with a mass of 1.25 gr, a density of 11.3 gr/cm3, and an impacting velocity of 100 m/s. The experimental tests conducted in a specially designed set-up were performed via an air-pressurized gun. 6061 aluminum adherends and an adhesive film were used to manufacture the bonded structure. Curves of the velocity and dynamic load against time were predicted for the joint under the impacting projectile. Failure and stress distributions in the adherend as well as in the adhesive layer were predicted that was validated via the experimental results. The prediction was made according to the worst case scenario that accounts the input data obtained from the quasi-static conditions.
BENCHMARKING VIRTUAL PERMEABILITY PREDICTIONS OF REAL FIBROUS MICROSTRUCTURE
Authors: MAY DAVID , SYERKO ELENA , SCHMIDT TIM , BINETRUY CHRISTOPHE , SILVA LUISA ROCHA DA , LOMOV STEPAN , ADVANI SURESH
Published: November 2021

ABSTRACT For fast and complete impregnation in Liquid Composite Molding, knowledge about the permeability of the fibrous reinforcement is required. While development of experimental methods continues, a parallel benchmark effort to numerically characterize permeability is being pursued. The approach was to send out the images of a real fibrous microstructure to a number of participants, in order for them to apply their methods for virtual permeability prediction. Via resin transfer molding a plate was manufactured, using the glass woven fabric Hexcel 01102 (295 g/m²) at a fiber volume content of 54% and a thermoset resin. From this plate, a specimen was scanned using a 3D x-ray microscope at a scan size of 1000 x 1000 x 1000 μm³ and a resolution of 0.521 μm³ per voxel. The sample extracted for the simulations with a size of 523 x 65 x 507 μm³ contains about 400 fibers of a single tow. It revealed a variation of filament diameters between 7.5-9.3 μm and a fiber volume content in average of 56.46% with a variation of 54 - 59% in the individual 2D-slices transverse to the fiber direction. The image segmentation was performed by 2D-slices, to which a Hough transform was applied to detect fiber centers and cross-sections. Then fiber paths were tracked through-out the slices by the closest neighbor algorithm. Finally, fiber paths were smoothened by means of the local regression using weighted linear least squares and a 1st degree polynomial model. The participants received a stack of 973 segmented (binary) 2D-images and a corresponding segmented 3D volume raw-file. They were asked to calculate the full permeability tensor components and fill out a detailed questionnaire including questions e.g. on applied flow models and conditions, numerical discretization and approximation methods, fluid properties etc. The received results scatter considerably over two orders of magnitude, although the participants were provided an already segmented image structure, thus eliminating from the beginning a significant source of variation that could have come from image processing. Model size, meshing and many other sources of variation were identified, allowing further specification of the guidelines for the next step.
A FAST METHOD FOR EVALUATING EFFECTS OF PROCESS PARAMETERS ON MORPHOLOGY OF SEMI-CRYSTALLINE THERMOPLASTIC COMPOSITES
Authors: WYNN MATHEW , ZOBEIRY NAVID
Published: November 2021

Semi-crystalline thermoplastics such as PEEK have microstructures that are influenced by process parameters like temperature cycle, humidity, and oxygen levels. Inclusions such as carbon fibers lead to heterogenous crystal nucleation. Further, manufacturing uncertainties involved with techniques such as automated fiber placement, compression molding, or induction welding influence the microstructure of thermoplastic composites. These contributing factors impact type (e.g., spherulitic, cross-linked, transcrystalline, and needle-like), size and distribution of morphologies in the material. Even with similar degrees of crystallinities, these differences affect mechanical properties and overall performance of composite parts. In this study, an experimental method has been developed that allows for fast evaluation of morphology as a function of process parameters in semi-crystalline thermoplastic composites. A compression fixture in a Dynamic Mechanical Analyzer (DMA) is used to process thin films of thermoplastics with embedded carbon fibers, sandwiched between thin glass covers, while carefully controlling processing conditions including temperature, pressure, and strain rate. The sample morphology is then analyzed using through transmission Polarizing Light Microscopy (PLM). Samples can be reprocessed using DMA several times to analyze changes in microstructure. This experimental approach allows for fast exploration of timetemperature- transformation relationships and their effects on morphology. This can be used to enhance our understanding of the material microstructure and develop more accurate process simulation tools, leading to optimization of processing parameters.
Coupled Learning Enabled Stochastic Programming with Endogenous Uncertainty
Authors: Liu Junyi , Li Guangyu , Sen Suvrajeet
Published: November 2021

Predictive analytics, empowered by machine learning, is usually followed by decision-making problems in prescriptive analytics. We extend the previous sequential prediction-optimization paradigm to a coupled scheme such that the prediction model can guide the decision problem to produce coordinated decisions yielding higher levels of performance. Specifically, for stochastic programming (SP) models with latently decision-dependent uncertainty, without any parametric assumption of the latent dependency, we develop a coupled learning enabled optimization (CLEO) algorithm in which the learning step of predicting the local dependency and the optimization step of computing a candidate decision are conducted interactively. The CLEO algorithm automatically balances the exploration and exploitation via the trust region method with active sampling. Under certain assumptions, we show that the sequence of solutions provided by CLEO converges to a directional stationary point of the original nonconvex and nonsmooth SP problem with probability 1. In addition, we present preliminary experimental results which demonstrate the computational potential of this data-driven approach.
Congenital Anomalous Azygos Vein Drainage Causing Pulmonary Embolus in a 91-Year-Old Patient
Authors: Low Kai En , Premathilake Panduke , Pullaperuma Lasanthi , Angel Tammy
Published: November 2021

Background: Retroaortic course and azygos continuation of aberrant left brachiocephalic vein is a rare venous anomaly, which is usually associated with congenital heart disease and pulmonary artery anomalies. Venous stasis is a cause of pulmonary arterial thromboembolism, which can result from venous anomalies. Case presentation: We describe the case of a 91-year-old female admitted to our hospital with shortness of breath diagnosed with pulmonary embolism and infarctions by a CT pulmonary angiogram. CT also showed aberrant left brachiocephalic vein with vascular webs at its retroaortic course and azygos continuation, suggesting chronic venous thrombosis, which was considered to be the suspected source of emboli. Conclusion: To our knowledge, this is the first report presenting this vascular anomaly manifesting with chronic venous thrombosis and pulmonary embolism. Although rare, awareness and identification of this entity is important, especially in the absence of obvious embolic sources or in patients with recurrent embolus/consolidation.
Política e expansão urbanas em Lavras-MG: o direito à cidade em disputa
Authors: Andrade Luís Fernando Silva , Brito Mozar José de
Published: November 2021

O presente artigo tem por objetivo apreender a regulação dos conflitos de interesses que marcaram e continuam marcando a disputa pelo direito à cidade em Lavras, Minas Gerais. O direito à cidade é uma demanda para uma urbanidade renovada e ao mesmo tempo um conceito pautado nos conceitos marxistas de valor de uso e valor de troca na cidade e uma reflexão de movimentos sociais e políticas urbanas de cunho progressista. No Brasil, as normas vigentes apresentam a função social da sociedade como preceito básico de atuação das municipalidades na gestão urbana. Em Lavras, cidade de médio porte do Sul de Minas Gerais, várias contradições e conflitos pelo uso do espaço social encerram um caso exemplar para o entendimento da complexidade da disputa pelo direito à cidade. Quanto à metodologia utilizou-se de pesquisa documental, entrevistas semiestruturadas e observação, sendo a análise de temática realizada a partir de categorias analíticas das teorias de formação sócio-espacial. Os resultados indicam a forte influência do poder econômico e de interesses privados na política urbana lavrense, numa abstração do espaço e preponderância do valor de troca na cidade. Tal situação ocasionou um conflito entre poder executivo local e o Ministério Público de Minas Gerais, cuja atuação é reforçada pelo movimento contrário à mineração em áreas urbanas na zona oeste do município iniciado por uma associação de moradores. Entre diferentes escalas de normas, influência do capital, inquéritos e ações civis públicas, a forma de atuação da prefeitura é modificada pelas imposições do Ministério Público, indicando a responsabilidade dos dirigentes do município no trato da coisa pública e no atendimento dos preceitos estipulados no Estatuto da Cidade, garantias fundamentais para a dignidade dos cidadãos na cidade.
Cooperação Interlocal em Três Versões: parcerias, governança regional e metropolitana
Authors: Machado José Angelo
Published: November 2021

Neste trabalho, com base em revisão bibliográfica, identificamos três agrupamentos de estudos dedicados a problemas de cooperação entre governos locais na literatura internacional: parcerias voluntárias, governança regional e gestão de regiões metropolitanas. Argumentamos que tais agrupamentos não apenas se referem a tipos distintos de associações como também, em cada um, lidam com diferentes formas de articulação entre os interesses dos associados. Parcerias voluntárias são associações intermunicipais para gestão de interesses comuns, se constituindo em torno de organizações baseadas no consenso entre as partes; associações de governança regional ou gestão metropolitana lidam também, embora sob condições distintas, com interesses não comuns e incluem temas para os quais governos locais atribuem diferente saliência, ou mesmo se colocam em posição conflitante. Os distintos agrupamentos se referem a obstáculos e dilemas institucionais próprios para a ação cooperativa, seja do ponto de vista dos poderes institucionais delegados à associação ou da amplitude do escopo da sua agenda.
A teoria dos direitos fundamentais de Robert Alexy como modelo analítico do direito social à moradia: argumentos de princípio no campo de referência de sua aplicabilidade imediata
Authors: Tavares Regina Lúcia Gonçalves , Gustin Miracy Barbosa de Sousa
Published: November 2021

O direito à moradia, situado como direito social fundamental, é aqui analisado sob um modelo analítico que permite sua classificação como um direito fundamental completo, essencialmente exigente tanto de ações positivas quanto negativas por parte do Estado, percepção teórica que então permite com que seu marco normativo constitucional seja pensado como dispositivo de aplicabilidade imediata e não sujeita à reserva do possível. Optou-se por uma análise teórica pela qual o correspondente normativo do direito social à moradia é estudado sob uma ótica principiológica que, partindo de Ronald Dworkin (2010; 2013), encontra em Robert Alexy (2014; 2015) sua grande justificativa teórica. O problema que se coloca neste trabalho é: a teoria dos direitos fundamentais de Alexy possibilita a construção de um modelo analítico do direito à moradia como um direito fundamental social de aplicabilidade imediata, porquanto capaz de referenciar teoricamente e de maneira robusta a jurisprudência que se aplica a este tipo de demanda? Os resultados permitiram encontrar um pujante sistema de pensamento segundo o qual o direito à moradia, como um direito fundamental completo, requer a necessidade do reconhecimento da plenitude de sua indiscutível aplicabilidade frente às questões apresentadas em demandas fundiárias nos quais é ele questionado.
Eleitoralismo e oligarquização da democracia: reflexões sobre o uso do sorteio como garantia do ideal republicano da não-dominação
Authors: De Sousa Rodrigo Ribeiro
Published: November 2021

Nos últimos anos, o “mal-estar” da população mundial com as regras e resultados da democracia representativa tornou-se um fato público e notório em grande parte das democracias do mundo. A corrupção do sistema político, as dificuldades de superação das desigualdades sociais e a incapacidade de inclusão das minorias refletem um domínio persistente das elites políticas, incompatível com os valores democráticos e republicanos. Partindo da constatação dos limites práticos dos governos representativos contemporâneos, de modo geral, e da democracia representativa brasileira, em particular, o propósito do artigo é o de debater em que medida a reintrodução do elemento do sorteio em nossas práticas políticas pode contribuir para uma reabilitação dos valores democráticos, promover a inclusão social e favorecer a implementação da liberdade como não-dominação, nos termos da formulação de Philip Pettit. Para tanto, serão abordadas referências teóricas recentes no campo das denominadas “inovações democráticas”, em especial a perspectiva de “democracia aberta”, de Hélène Landemore. A metodologia empregada é essencialmente a análise bibliográfica dos textos estudados.
Democracia, o soberano imanente e o fim da exceção: uma crítica ao decisionismo de Carl Schmitt
Authors: Benjamin Cássio Corrêa
Published: November 2021

O decisionismo é a estrutura do pensamento político e jurídico de Schmitt. Por isso, a famosa figura da exceção. Por isso, também, a figura central do soberano teísta. Nosso objetivo nesse artigo é a análise dos pressupostos do decisionismo de Schmitt, mostrando como tais pressupostos são incompatíveis com a imanência e, portanto, com a democracia. Apresentaremos, então, alguns traços centrais de uma noção de democracia baseada na imanência, como o fim da exceção e o soberano imanente. Metodologicamente, faremos uma leitura dos escritos de Schmitt nos quais a noção de decisionismo é elaborada, além de comentadores destacados que tratam da questão
Current Updates on Covid-19 Vaccine Research and an Overview of Therapeutic Drug Research
Authors: Oviyaasri Oviyaasri , Manjuladevi M. , Kalaiselvan S. , Haripriyan U.
Published: November 2021

The world is presently hectic in a battle against the strong and lethal COVID-19 virus, which is not only dangerous to the body but also psychologically distressing due to the growing number of patients infected and dying worldwide. This paper includes a concise overview of the possible therapies as well as the elements associated with intensive care, which have been identified with promising clinical outcomes, based on the knowledge we have gathered so far. Furthermore, as the SARS-CoV-2 virus is better understood, recent drugs focussing certain parts of the virus are being developed, and anti-SARS-CoV-2 vaccines are being researched. This timely study examines the existing condition of COVID-19 across the globe. This topic will bring to light the potential for drug development and vaccination in different parts of the world to combat the epidemic, and some of this may be of use in the future.
Scanning Electron Microscopic Study of Aplectana Duttaphryni Sou, Sow and Nandi, 2014 from A New Frog Host, Fejervarya limnocharis in West Bengal
Authors: Banerjee Siddharthasankar , Sou Sujan Kumar
Published: November 2021

Aplectana duttaphryni Sou, Sow and Nandi, 2014 was first reported in Kulti, Asansol coal-mine region, West Bengal from a toad, Duttaphrynus melanostictus (Schneider, 1899) only using light microscope. Present article describes, A. duttaphryni in details collected from the rectum of an anuran frog, Fejervarya limnocharis (Gravenhorst, 1829) in Birbhum district, West Bengal. Aplectana duttaphryni is reported for the first time from Birbhum district, West Bengal. The parasites identified by its lanceolate shaped gubernaculum, presence of 1 pair of similar and equal spicules and also with the presence of 3 pairs of preanal papillae, 2 pairs of adanal papillae, 13 pairs of postanal papillae and single papillae on the upper lip of anus. In the present study, Birbhum district recorded as new geographical locality and F. limnocharis recorded as a new host.
Larvicidal Activity of Selected Plant Extracts Against the Screwworm Fly Chrysomya Albiceps
Authors: Al-Jameeli Mohammad M. , Shaher Fekri
Published: November 2021

Myiasis is a kind of parasitic disease originating from the invasion of tissues of domestic animals by dipteran larvae. Chrysomya albicebs is a type of screwworm fly spread in the tropical areas and known to cause myiasis among live human and animals leading to health problems and high economic losses to dairy producers. Management and control of this pest is needed to overcome these losses.

Nowadays, natural botanical products have been increasingly investigated as controlling agents against insects of medical and veterinary importance. This research was designed to evaluate the larvicidal effect of the total extracts of three plants, Ficus palmate, Juniperus procera and Nerium oleander against screwworm fly Chrysomya albiceps. The plants leaves were extracted with organic solvents mixture methanol : chloroform (1:1) and were tested against the second larval instar of C. albiceps using feeding and dipping methods. The extracts caused larval mortalities in the order of F. palmate> N. oleander > J. procer with IC50 values of 15.97, 33.73 and 37.24, respectively using feeding method and in the order N. oleander > F. palmate > J. procera with IC50 values of 43.12, 47.41 and 73.39, respectively using dipping method. It is concluded that the F. palmate followed by N. oleander and J. procera are candidates to use in controlling the larvae of myiasis-caused fly C. albiceps.
Study of Salted Octopus Drying Kinetics and Hygroscopy from Artisanal Fishing in Agadir Region
Authors: Lekra Mounia , Vezaz Zeinebou Hamma
Published: November 2021

Salt-and-dry technique is an artisanal fish conservation method adopted in the Maghreb countries which is based on lowering the water activity. This latter factor is crucial in food preservation, where the relationship between the water activity and the water content of the salted octopus helps control its storage. However, the realization of this processing in controlled conditions is limited by the lack of information regarding the drying time and the behavior towards humidity of this specie. This work describes the drying kinetics by plotting the drying curve (70 ° C; 1.5 m/s) and helps define the salted octopus drying time. Also it presents the desorption and adsorption isotherms at three temperatures which represent the storage temperatures (30, 40 and 50°C) following the gravimetric method. The drying of the salted octopus carried out helped reduce the water activity to a value of 0.63 and the water content of 0.505 g water/g MS during 10 hours. In addition, the sorption curves were experimentally determined and modeled by polynomial regression of order 4. The fitting has given correlation coefficients close to 1 for the three temperatures.
Birefringent atomic vapor laser lock in a hollow cathode lamp
Authors: Sato Takumi , Hayakawa Yusuke , Okamoto Naohiro , Shimomura Yusuke , Aoki Takatoshi , Torii Yoshio
Published: November 2021

We report a robust method of stabilizing a laser to the frequency of an atomic transition using a hollow cathode lamp. In contrast to the standard dichroic atomic vapor laser lock method, which uses dichroism induced by a longitudinal magnetic field, we employ birefringence induced by a transversal magnetic field. We applied this method to the

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transition (461 nm) of Sr. Although the hollow cathode is made of ferromagnetic material, we successfully applied a magnetic field of sufficient strength to obtain an error signal with a theoretical maximum slope. This method may be applied to other hollow cathode lamps of different atomic species.
High energy switchable pulsed High-order Mode beams in a mode-locking Raman all-fiber laser with high efficiency
Authors: Huang Maolin , Wu Jiadong , Hong Jiahao , Lei Hualei , Zhao Chujun , Chen Yu , Fan Dianyuan
Published: November 2021

High energy pulsed High-order Mode (HOM) beams has great potential in materials processing and particle acceleration. We experimentally demonstrate a high energy mode-locking Raman all-fiber laser with switchable HOM state. A home-made fiber mode-selective coupler (MSC) is used as the mode converter with a wide bandwidth of 60 nm. By combining advantages of MSC and stimulated Raman scattering, 1.1 μJ pulsed HOM beams directly emitting from the all-fiber cavity can be achieved. After controlling the category and phase delay of vector modal superposition, different pulsed HOM beams including cylindrical vector beams (CVBs) (radial and angular) and optical vortex beams (OVBs) are reasonably obtained with high purity (all over 95%), as well as arbitrary switching. Furtherly, the slope efficiency of HOM beams in the mode-locking and continuous wave operations are as much as 20.3% and 31.8%, respectively. It may provide an effective way to achieve high energy pulsed HOM beams.
Non-line-of-sight imaging under white-light illumination: a two-step deep learning approach
Authors: Zheng Shanshan , Liao Meihua , Wang Fei , He Wenqi , Peng Xiang , Situ Guohai
Published: November 2021

Non-line-of-sight (NLOS) imaging has received considerable attentions for its ability to recover occluded objects from an indirect view. Various NLOS imaging techniques have been demonstrated recently. Here, we propose a white-light NLOS imaging method that is equipped only with an ordinary camera, and not necessary to operate under active coherent illumination as in other existing NLOS systems. The central idea is to incorporate speckle correlation-based model into a deep neural network (DNN), and form a two-step DNN strategy that endeavors to learn the optimization of the scattered pattern autocorrelation and object image reconstruction, respectively. Optical experiments are carried out to demonstrate the proposed method.
Improvement of a floating 3D light field display based on a telecentric retroreflector and an optimized 3D image source
Authors: Gao Xin , Yu Xunbo , Sang Xinzhu , Liu Li , Yan Binbin
Published: November 2021

For a floating three-dimensional (3D) display system using a prism type retroreflector, non-retroreflected light and a blurred 3D image source are two key causes of the deterioration in image quality. In the present study, ray tracing is used to analyze the light distribution of a retroreflector at different incident angles. Based on this analysis, a telecentric retroreflector (TCRR) is proposed to suppress non-retroreflected light without sacrificing the viewing angle. A contrast transfer function (CTF) is used to evaluate the optical performance of the TCRR. To improve the 3D image source, the relationship between the root mean square (RMS) of the voxels and the 3D image quality is discussed, and an aspheric lens array is designed to reduce aberrations. Computational simulation results reveal that the structural similarity (SSIM) of the 3D image source increased to 0.9415. An experimental prototype system combining the TCRR and optimized 3D image source is then built. Experimental analysis demonstrates that the proposed method suppresses non-retroreflected light and improves the 3D image source. In particular, a clear floating 3D image with a floating distance of 70 mm and a viewing angle of 50° can be achieved
180 Gbit/s Si3N4-waveguide coupled germanium photodetector with improved quantum efficiency
Authors: Hu Xiao , Wu Dingyi , Chen Daigao , Wang Lei , Xiao Xi , Yu Shaohua
Published: November 2021

A high quantum efficiency (QE) and high-speed silicon nitride (

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3

N

4

) waveguide coupled germanium-on-silicon photodetector (Ge-on-Si PD) is presented. The proposed device is fabricated in a commercial 90 nm silicon photonics process platform. By decreasing the spacing between the tapered

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waveguide and the bottom Si to 200 nm and the

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thickness to 300 nm, the QE is significantly improved. Although the theoretical responsivity can reach up to 0.92 A/W at 1550 nm, the measured value is calculated to be approximately 0.61 A/W. The maximum experimental responsivity is about 0.9 A/W at 1485 nm. The 3 dB optoelectrical bandwidth of up to 54 GHz is demonstrated at a

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V

bias. Additionally, the 80, 90, 100, and 105 Gbit/s non-return-to-zero on-off-keying and the 150, 160, 170, and 180 Gbit/s four-level pulse amplitude modulation clear openings of the electrical eye diagrams are attained. Overall, the

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-waveguide coupled Ge-on-Si PD in this work possesses higher QE and operates at the highest data rates reported so far.
Coaxial double-hole PEDOT: PSS electrodes achieving tunable terahertz zoomable convergence
Authors: Li Shuai , Tian Hao , Tan Peng , Wang Guanchao , Guo Wenpeng , Wang Jing , Zhang Yao , Hu Chengpeng , Meng Xiangda , Zhou Zhongxiang
Published: November 2021

The local wavefront modulation technique in the terahertz band is an important basis for the development of terahertz modulation technology. Here, an electrically controlled convergent tunable device based on patterned transparent electrode poly (3, 4-ethylenedioxythiophene): poly (styrene sulfonate) (PEDOT: PSS) is realized to locally tune the terahertz wavefront. The device consists of two substrates with circular-hole electrodes and liquid crystal sandwiched between them. The refractive index gradient of liquid crystal in the device can be generated by the coaxial double-hole electrodes, which realize continuous control of significant focusing of the terahertz wave. The test results show that the focal length can be modulated in the range of 3–12 cm with varied external voltage; when it varies from 3 to 8 V, the

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/

e

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radius of the spot decreases to 1.3 mm, 0.27 times the initial state, and the spot central intensity magnification increases gradually with the change, up to 3.31 times. The acquisition of the large tunable focal length range of the continuous terahertz zoom device shows that the construction of the gradient refractive index is an important method to regulate the terahertz wavefront by optical means, which greatly promotes the research of terahertz imaging devices.
Scheme for optimizing a direct current component in a photonics-assisted OFDM MMW system
Authors: Zhao Li , Sang Bohan , Zhou Wen , Wei Yi , Yu Jianjun
Published: November 2021

This Letter proposes a new scheme for optimizing a direct current (DC) component to enable both the frequency offset estimation and system performance improvement by controlling the IQ modulator to adjust the DC component in a photonics-assisted OFDM MMW system. Compared with the traditional method, a large DC component is used as the pilot frequency for frequency offset estimation. When a small DC component is used, the system performance is better. A 3 Gbaud 16QAM OFDM signal is delivered over 70 m wireless, enabling a 3.5 dB sensitivity improvement at the bit error rate threshold of

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in the E-band.
Dual-microcomb generation in a synchronously driven waveguide ring resonator
Authors: Xu Yiqing , Erkintalo Miro , Lin Yi , Coen Stéphane , Ma Huilian , Murdoch Stuart G.
Published: November 2021

Microcombs—optical frequency combs generated in coherently driven nonlinear microresonators—have attracted significant attention over the last decade. The ability to generate two such combs in a single resonator device has, in particular, enabled a host of applications from spectroscopy to imaging. Concurrently, novel comb generation techniques such as synchronous pulsed driving have been developed to enhance the efficiency and flexibility of microcomb generation. Here, we report on the first, to the best of our knowledge, experimental demonstration of dual-microcomb generation via synchronous pulsed pumping of a single microresonator. Specifically, we use two electro-optically generated pulse trains derived from a common continuous wave laser to simultaneously drive two orthogonal polarization modes of an integrated silica ring resonator, observing the generation of coherent dissipative Kerr cavity soliton combs on both polarization axes. Thanks to the resonator birefringence, the two soliton combs are associated with different repetition rates, thus realizing a dual-microcomb source. To illustrate the source’s application potential, we demonstrate proof-of-concept spectroscopic measurements.
Toward generalized forked gratings via deep learning
Authors: Zhao Yue , Wang Enliang , Cao Fulin , Xie Changqing
Published: November 2021

We extend the concept of forked gratings to include the ability of high diffraction orders suppression of a single pair of vortex beams. The main idea is to appropriately distribute rectangular holes over each open space of a conventional forked grating. We further introduce the deep convolutional neural network algorithm to assist us in reconstructing and obtaining the optimal parameter of generalized forked grating. The recovery rate of our neural network is 92.3%. The 3rd order diffracted light intensity can be as low as 0.067% of the desired 1st order diffracted light intensity. The verification experiment results are also presented, confirming the helical phase structures with multitopological charges. The high diffraction orders suppression properties of the generalized forked gratings hold promise for broad applications, such as imaging, microscopy, and fundamental physics observation.
Photonics-assisted joint high-speed communication and high-resolution radar detection system
Authors: Wang Yanyi , Dong Ze , Ding Junjie , Li Weiping , Wang Mingxu , Zhao Feng , Yu Jianjun
Published: November 2021

A photonics-aided dual-functional system that can simultaneously implement high-speed communication and high-resolution radar detection is proposed. In the proposed system, high-speed orthogonal frequency division multiplexing signals and broadband linear frequency modulated signals are simultaneously realized based on photonic heterodyning. Based on this system, a net rate of 46.55 Gbit/s and radar with a 15 GHz bandwidth in the W-band were achieved.
Noninvasive imaging of two isolated objects through a thin scattering medium beyond the 3D optical memory effect by speckle-based difference strategy
Authors: He Wenqi , Wei Yuchen , Lu Dajiang , Li Xianye , Liao Meihua , Peng Xiang
Published: November 2021

The shape of two objects hidden behind a thin scattering medium is retrieved by the presented method. One of the two objects keeps stationary, while the other one is supposed to be gradually moving, and the Euclidean distance between them is always beyond the range of the 3D optical memory effect. We capture two speckle patterns to image the two isolated objects by using a developed speckle-differential-based strategy and the traditional speckle autocorrelation technique. The feasibility of our method is demonstrated by theoretical analysis and a set of experiments.
Electrically controllable terahertz metamaterials with large tunabilities and low operating electric fields using electrowetting-on-dielectric cells
Authors: Silalahi Harry Miyosi , Shih Yi-Hong , Lin Shih-Hung , Chen Yi-Ting , Wei Wan-Yi , Chao Pei-Ling , Huang Chia-Yi
Published: November 2021

A simple method that is compatible with all geometrical structures of terahertz (THz) metamaterials for increasing their frequency tunabilities and decreasing their operating electric fields is proposed. This method uses the displacement of glycerol droplets with various volumes to tune the resonance frequency of a THz metamaterial in an electrowetting-on-dielectric (EWOD) cell. The experimental results reveal that the THz metamaterial has a large frequency tunability of 28% at an operating electric field that is smaller than 0.2 V/µm as the glycerol droplets move in and out of the path of a THz beam. The frequency tunability is large because the near field of the metamaterial “experiences” a large difference between the refractive indices of glycerol and air. The EWOD cell with the THz metamaterial is a great achievement for developing electrically controllable band-stop filters with large frequency tunabilities and small operating electric fields.
Multi-band low-noise microwave-signal-receiving system with a photonic frequency down-conversion and transfer-learning network
Authors: Yi Sicheng , Xu Shaofu , Zou Weiwen
Published: November 2021

In this Letter, we propose and demonstrate a multi-band signal-receiving system, powered by photonic frequency down-conversion and transfer learning. A photonic frequency down-conversion system directly receives the microwave signals, and the transfer-learning network (TLN) lowers the noise in the signals. In addition to the effectiveness of denoising, the TLN also features ultra-fast retraining for signals of different types or different multi-band frequencies. Experimental results showed that the proposed microwave-signal-receiving system can improve the signal-to-noise (SNR) ratio of signals of different types, SNR, and duty cycles. For network retraining, the TLN requires only three times less data and 10 times less time consumption than conventional training methods.
Determination of optical constants and scattering properties of transparent polymers for use in optoelectronics
Authors: Bauer Joachim , Fursenko Oksana , Heinrich Friedhelm , Gutke Marko , Kornejew Eckhart , Broedel Oliver , Dietzel Birgit , Kaltenbach Alexander , Burkhardt Martin , Edling Matthias , Steglich Patrick , Herzog Michael , Schrader Sigurd
Published: November 2021

Knowledge of optical constants, i.e. refractive index n and extinction coefficient k, and light scattering properties of optical polymers are required to optimize micro-optics for light-emitting diodes in terms of efficiency, color properties and light distribution. We present here a model-based diagnostic approach to determine the optical properties of polymers, which should be particularly useful in the development of plastics for optical applications. Optical constants and scattering coefficients were obtained from transmission and reflection measurements in a wavelength range from UV to NIR taking into account scattering effects due to rough surfaces and volume inhomogeneity. Based on the models for the dielectric function, the molecular optical transition energies Eg, critical point energies, Urbach energies and exciton transition energies were determined. Rayleigh and Mie scattering model and van de Hulst's anomalous diffraction theory were applied to characterize scattering due to volume inhomogeneities. Scalar diffraction theory was applied to account for surface roughness scattering. Atomic force microscopy with nanomechanical characterization was used to characterize domains in size and shape and to assign optical scattering to a suitable morphological model. The combined optical and mechanical characterization help to improve the qualification of new polymer materials for optical applications.