bluuebunny/crossref_metadata_2025 huggingface dataset:
Gang membership and sexual violence: associations with childhood maltreatment and psychiatric morbidity
Authors: Coid Jeremy , González Rafael A. , Kallis Constantinos , Zhang Yamin , Liu YuanYuan , Wood Jane , Quigg Zara , Ullrich Simone
Published: April 2020

Background

Gang members engage in many high-risk sexual activities that may be associated with psychiatric morbidity. Victim-focused research finds high prevalence of sexual violence towards women affiliated with gangs.

Aims

To investigate associations between childhood maltreatment and psychiatric morbidity on coercive and high-risk sexual behaviour among gang members.

Method

Cross-sectional survey of 4665 men 18–34 years in Great Britain using random location sampling. The survey oversampled men from areas with high levels of violence and gang membership. Participants completed questionnaires covering violent and sexual behaviours, experiences of childhood disadvantage and trauma, and psychiatric diagnoses using standardised instruments.

Results

Antisocial men and gang members had high levels of sexual violence and multiple risk behaviours for sexually transmitted infections, childhood maltreatment and mental disorders, including addictions. Physical, sexual and emotional trauma were strongly associated with adult sexual behaviour and more prevalent among gang members. Other violent behaviour, psychiatric morbidity and addictions accounted for high-risk and compulsive sexual behaviours among gang members but not antisocial men. Gang members showed precursors before age 15 years of adult preference for coercive rather than consenting sexual behaviour.

Conclusions

Gang members show inordinately high levels of childhood trauma and disadvantage, sexual and non-sexual violence, and psychiatric disorders, which are interrelated. The public health problem of sexual victimisation of affiliated women is explained by these findings. Healthcare professionals may have difficulties promoting desistance from adverse health-related behaviours among gang members whose multiple high-risk and violent sexual behaviours are associated with psychiatric morbidity, particularly addictions.
Duplication 6q24: More Than Just Diabetes
Authors: Gore Rachel H , Nikita Maria Eleni , Newton Paula G , Carter Rebecca G , Reyes-Bautista Jeanine , Greene Carol L
Published: April 2020

Chromosome 6q24-related transient neonatal diabetes mellitus is characterized by intrauterine growth restriction and low birth weight, with neonatal hyperglycemia resolving by 18 months and an increased risk for type 2 diabetes in adulthood. Molecularly, it is caused by overexpression of the 6q24 imprinted chromosomal region due to a duplication, uniparental disomy, or abnormal methylation. Conventional testing for this condition analyzes methylation patterns at the 6q24 locus but does not evaluate for the presence of other surrounding chromosomal abnormalities. We report a female with a history of neonatal hyperglycemia due to a paternally inherited duplication at chromosomal location 6q24. She subsequently presented to the pediatric genetics clinic at 15 months of age with developmental delay and abnormal balance. Microarray analysis identified a larger 14 Mb chromosomal duplication from 6q24 to 6q25.2, consistent with a diagnosis of duplication 6q syndrome. This case highlights the clinical importance of pursuing further genetic evaluation in patients diagnosed with chromosome 6q24-related neonatal hyperglycemia via targeted methylation-specific multiplex ligation-dependent probe amplification analysis identifying a duplication in this region. Early identification and intervention can improve developmental outcomes for patients with larger chromosome 6q duplications.
The regulation of Yorkie, YAP and TAZ: new insights into the Hippo pathway
Authors: Manning Samuel A. , Kroeger Benjamin , Harvey Kieran F.
Published: April 2020

The Hippo pathway is a highly conserved signalling pathway that regulates multiple biological processes, including organ size control and cell fate. Since its discovery, genetic and biochemical studies have elucidated several key signalling steps important for pathway activation and deactivation. In recent years, technical advances in microscopy and genome modification have allowed new insights into Hippo signalling to be revealed. These studies have highlighted that the nuclear-cytoplasmic shuttling behaviour of the Hippo pathway transcriptional co-activators Yorkie, YAP and TAZ is far more dynamic than previously appreciated, and YAP and TAZ are also regulated by liquid-liquid phase separation. Here, we review our current understanding of Yorkie, YAP and TAZ regulation, with a focus on recent microscopy-based studies.
Smad4-dependent morphogenic signals control the maturation and axonal targeting of basal vomeronasal sensory neurons to the accessory olfactory bulb
Authors: Naik Ankana S. , Lin Jennifer M. , Taroc Ed Zandro M. , Katreddi Raghu R. , Frias Jesus A. , Lemus Alex A. , Sammons Morgan A. , Forni Paolo E.
Published: April 2020

The vomeronasal organ (VNO) contains two main types of vomeronasal sensory neurons (VSNs) that express distinct vomeronasal receptor (VR) genes and localize to specific regions of the neuroepithelium. Morphogenic signals are crucial in defining neuronal identity and network formation; however, if and what signals control maturation and homeostasis of VSNs is largely unexplored. Here, we found transforming growth factor β (TGFβ) and bone morphogenetic protein (BMP) signal transduction in postnatal mice, with BMP signaling being restricted to basal VSNs and at the marginal zones of the VNO: the site of neurogenesis. Using different Smad4 conditional knockout mouse models, we disrupted canonical TGFβ/BMP signaling in either maturing basal VSNs (bVSNs) or all mature VSNs. Smad4 loss of function in immature bVSNs compromises dendritic knob formation, pheromone induced activation, correct glomeruli formation in the accessory olfactory bulb (AOB) and survival. However, Smad4 loss of function in all mature VSNs only compromises correct glomeruli formation in the posterior AOB. Our results indicate that Smad4-mediated signaling drives the functional maturation and connectivity of basal VSNs.
Runx1 promotes scar deposition and inhibits myocardial proliferation and survival during zebrafish heart regeneration
Authors: Koth Jana , Wang Xiaonan , Killen Abigail C. , Stockdale William T. , Potts Helen G. , Jefferson Andrew , Bonkhofer Florian , Riley Paul R. , Patient Roger K. , Göttgens Berthold , Mommersteeg Mathilda T. M.
Published: April 2020

Runx1 is a transcription factor that plays a key role in determining the proliferative and differential state of multiple cell types, during both development and adulthood. Here, we report how Runx1 is specifically upregulated at the injury site during zebrafish heart regeneration, and that absence of runx1 results in increased myocardial survival and proliferation, and overall heart regeneration, accompanied by decreased fibrosis. Using single cell sequencing, we found that the wild-type injury site consists of Runx1-positive endocardial cells and thrombocytes that induce expression of smooth muscle and collagen genes. Both these populations cannot be identified in runx1 mutant wounds that contain less collagen and fibrin. The reduction in fibrin in the mutant is further explained by reduced myofibroblast formation and upregulation of components of the fibrin degradation pathway, including plasminogen receptor annexin 2A as well as downregulation of plasminogen activator inhibitor serpine1 in myocardium and endocardium, resulting in increased levels of plasminogen. Our findings suggest that Runx1 controls the regenerative response of multiple cardiac cell types and that targeting Runx1 is a novel therapeutic strategy for inducing endogenous heart repair.
Mechanisms and consequences of flight polyphenisms in an outbreaking bark beetle species
Authors: Jones Kelsey L. , Rajabzadeh Rahmatollah , Ishangulyyeva Guncha , Erbilgin Nadir , Evenden Maya L.
Published: April 2020

Flight polyphenisms naturally occur as discrete or continuous traits in insects. Discrete flight polyphenisms include winged and wingless morphs, whereas continuous flight polyphenisms can take the form of short- or long-distance fliers. The mountain pine beetle (Dendroctonus ponderosae) exhibits polyphenic variation in flight distance but the consequences of this flight variation on life history strategies of beetles is unknown. This study assessed the effect of flight on two particular aspects of beetle biology: (1) an energetic trade-off between flight distance and host colonisation capacity; and (2) the relationship between flight distance and pheromone production. A 23-h flight treatment was applied to a subset of beetles using computer. After flight treatment, both flown and unflown (control) beetles were given the opportunity to colonise bolts of host trees, and beetles that entered hosts were aerated to collect pheromone. A trade-off occurred between initiation of host colonisation and percent body weight lost during flight, which indicates energy-use during flight affects host acceptance in female mountain pine beetles. Furthermore, production of the aggregation pheromone trans-verbenol by female beetles was influenced by both percent weight lost during flight and flight distance. Male production of exo-brevicomin was affected by beetle condition following flight but not by the energy used during flight. These novel results give new insight into the polyphenic flight behaviour of mountain pine beetles. Flight variation is adaptive by acting to maintain population levels through safe and risky host colonisation strategies. These findings suggest mechanisms that facilitate the extremities of the continuous flight polyphenism spectrum. These opposing mechanisms appear to maintain the high variation in flight exhibited by this species.
Complementary and alternative medicines used by cancer patients to cope with nausea
Authors: Toygar İsmail , Yeşilbalkan Öznur Usta , Kürkütlü Merve , Temelli Arzu
Published: April 2020

Background: Cancer is a common health problem in the world. Nausea is one of the most common symptoms in cancer patients. Cancer patients often apply to complementary and alternative medicines (CAM) in symptom management.Aim: The aim of this study was to determine the CAM methods used by cancer patients to cope with nausea.Material and Method: The study has a descriptive design and its data were collected in an adult oncology unit of a university hospital between July and September 2019. A total of 205 patients diagnosed with cancer for at least 6 months were included in the study. Data were collected by using the Individual Identification Form and Attitude Scale against Holistic Complementary Medicine. Data were analyzed with SPSS 25.0 package program. Written permission was obtained from the relevant ethics committee, hospital and participants to conduct the study.Results: Sixty and a half percent of the subjects were female and the mean age was 50.64 ± 15.27. While 31.7% of the patients had information about CAM, the main source of information was the internet and social media (64.6%). It was found that 14.63% of the patients applied to a CAM to cope with nausea. The most commonly used method is phytotherapy with 86.67%. The total score environment of the Holistic Complementary Medicine Attitude Scale was 33.49 ± 4.63.Conclusions: It was found that the rate of using CAM in coping with nausea in cancer patients was lower than other symptoms in the literature and the most commonly used method was phytotherapy. Patients' attitudes towards CAM were found to be positive.
RamaNet: Computational de novo helical protein backbone design using a long short-term memory generative adversarial neural network
Authors: Sabban Sari , Markovsky Mikhail
Published: April 2020

The ability to perform de novo protein design will allow researchers to expand the variety of available proteins. By designing synthetic structures computationally, they can utilise more structures than those available in the Protein Data Bank, design structures that are not found in nature, or direct the design of proteins to acquire a specific desired structure. While some researchers attempt to design proteins from first physical and thermodynamic principals, we decided to attempt to test whether it is possible to perform de novo helical protein design ofjust the backbone statistically using machine learning by building a model that uses a long short-term memory (LSTM) generative adversarial network (GAN) architecture. The LSTM-based GAN model used only theφandψangles of each residue from an augmented dataset of only helical protein structures. Though the network’s generated backbone structures were not perfect, they were idealised and evaluated post generation where the non-ideal structures were filtered out and the adequate structures kept. The results were successful in developing a logical, rigid, compact,helical protein backbone topology. This paper is a proof of concept that shows it is possible to generate a novel helical backbone topology using an LSTM-GAN architecture using only theφandψangles as features. The next step is to attempt to use these backbone topologies and sequence design them to form complete protein structures.
An environment for sustainable research software in Germany and beyond: current state, open challenges, and call for action
Authors: Anzt Hartwig , Bach Felix , Druskat Stephan , Löffler Frank , Loewe Axel , Renard Bernhard Y. , Seemann Gunnar , Struck Alexander , Achhammer Elke , Aggarwal Piush , Appel Franziska , Bader Michael , Brusch Lutz , Busse Christian , Chourdakis Gerasimos , Dabrowski Piotr Wojciech , Ebert Peter , Flemisch Bernd , Friedl Sven , Fritzsch Bernadette , Funk Maximilian D. , Gast Volker , Goth Florian , Grad Jean-Noël , Hermann Sibylle , Hohmann Florian , Janosch Stephan , Kutra Dominik , Linxweiler Jan , Muth Thilo , Peters-Kottig Wolfgang , Rack Fabian , Raters Fabian H.C. , Rave Stephan , Reina Guido , Reißig Malte , Ropinski Timo , Schaarschmidt Joerg , Seibold Heidi , Thiele Jan P. , Uekermann Benjamin , Unger Stefan , Weeber Rudolf
Published: April 2020

Research software has become a central asset in academic research. It optimizes existing and enables new research methods, implements and embeds research knowledge, and constitutes an essential research product in itself. Research software must be sustainable in order to understand, replicate, reproduce, and build upon existing research or conduct new research effectively. In other words, software must be available, discoverable, usable, and adaptable to new needs, both now and in the future. Research software therefore requires an environment that supports sustainability.

Hence, a change is needed in the way research software development and maintenance are currently motivated, incentivized, funded, structurally and infrastructurally supported, and legally treated. Failing to do so will threaten the quality and validity of research. In this paper, we identify challenges for research software sustainability in Germany and beyond, in terms of motivation, selection, research software engineering personnel, funding, infrastructure, and legal aspects. Besides researchers, we specifically address political and academic decision-makers to increase awareness of the importance and needs of sustainable research software practices. In particular, we recommend strategies and measures to create an environment for sustainable research software, with the ultimate goal to ensure that software-driven research is valid, reproducible and sustainable, and that software is recognized as a first class citizen in research. This paper is the outcome of two workshops run in Germany in 2019, at deRSE19 - the first International Conference of Research Software Engineers in Germany - and a dedicated DFG-supported follow-up workshop in Berlin.
Inferring the number of COVID-19 cases from recently reported deaths
Authors: Jombart Thibaut , van Zandvoort Kevin , Russell Timothy W. , Jarvis Christopher I. , Gimma Amy , Abbott Sam , Clifford Samuel , Funk Sebastian , Gibbs Hamish , Liu Yang , Pearson Carl A. B. , Bosse Nikos I. ,   Centre for the Mathematical Modelling of Infectious Diseases COVID-19 Working Group, Eggo Rosalind M. , Kucharski Adam J. , Edmunds W. John
Published: April 2020

We estimate the number of COVID-19 cases from newly reported deaths in a population without previous reports. Our results suggest that by the time a single death occurs, hundreds to thousands of cases are likely to be present in that population. This suggests containment via contact tracing will be challenging at this point, and other response strategies should be considered. Our approach is implemented in a publicly available, user-friendly, online tool.
ETF Activity and Informational Efficiency of Underlying Securities
Authors: Glosten Lawrence , Nallareddy Suresh , Zou Yuan
Published: April 2020

This paper investigates the effect of exchange-traded funds’ (ETFs’) activity on the short-run informational efficiency of their underlying securities. We find that ETF activity increases short-run informational efficiency for stocks with weak information environments. The increase in informational efficiency results from the timely incorporation of systematic earnings information. In contrast, we find no such effect for stocks with stronger information environments. ETF activity increases return comovement, and this increase is partly attributable to the timely incorporation of systematic earnings information. Further, ETF activity is associated with an attenuation of postearnings-announcement drift and an increase in active share lending.

This paper was accepted by Suraj Srinivasan, accounting.
Por que vendem tanto? O consumo de historiografia comercial no Brasil em tempos de crise (2013-2019)
Authors: Oliveira Rodrigo Perez
Published: April 2020

O objetivo deste artigo é examinar o consumo de historiografia comercial no Brasil contemporâneo, caracterizado por uma experiência de crise institucional que, segundo a bibliografia especializada, começou em meados de 2013. O corpus de fontes primárias analisado, portanto, consiste nos livros que, evocando a identidade genérica historiográfica, encontraram grande acolhida no mercado editorial. Em virtude de critérios esclarecidos ao longo do texto, o esforço de análise está concentrado em dois livros específicos: “O guia politicamente incorreto da história do Brasil”, de Leandro Narloch e publicado em 2009, e “A elite do atraso”, de Jessé Souza e publicado em 2017. A hipótese é de que o sucesso comercial desses livros se explica pela capacidade dos autores em mobilizar enunciados de síntese explicativa capazes de proporcionar sensação de orientação histórica.
Malnutrition in acute stroke: what are we treating?
Authors: Baby Priya
Published: April 2020

Malnutrition is an important concern in patients with acute stroke. It is a major factor contributing to poor outcome. There are several factors that are associated with malnutrition in acute stroke. Hypermetabolism, associated with acute illness, is one of the major factors. I have examined the metabolic changes after acute stroke and the methods of assessing malnutrition in the light of the literature. The pathophysiological background of how the metabolic changes in acute stroke contribute to altered indices of nutrition has also been examined. The tools available for marking malnutrition in acute stroke are appraised on the basis of the pathobiology.
Metastatic spinal cord compression
Authors: Patnaik Surendra , Turner Joseph , Inaparthy Praveen , Kieffer Will KM
Published: April 2020

Metastatic spinal cord compression is compression of the spinal cord or cauda equina as a result of metastatic deposits in the spinal column. It affects approximately 4000 cases per year in England and Wales. Prompt identification and treatment of metastatic spinal cord compression is necessary to prevent irreversible neurological injury, treat pain and maintain patients' mobility, function and independence. Survival of patients with common malignancies has improved significantly with the ongoing development of radiotherapy and chemotherapy, as well as improved surgical treatment of resectable primary tumours. This article outlines the clinical approach to presentation, pathophysiology, diagnosis and management.
Identification and characterization of Flavobacteriaceae from farmed Oreochromis niloticus and Clarius gariepinus in Uganda
Authors: RACHEAL AMONO , KASANGA CHRISTOPHER J. , BYARUGABA DENIS K.
Published: April 2020

Racheal A, Kasanga CJ, Byarugaba DK. 2018. Identification and characterization of Flavobacteriaceae from farmed Oreochromis niloticusand Clarius garieoinus. Bonorowo Wetlands 2: 42-50. Bacteria under family Flavobacteriaceae (in this study were also referred to as Flavobacteria) are important pathogens of fish, people, many other animals and plants. In this study, Flavobacteria from Nile tilapia (Oreochromis niloticus) and African catfish (Clarius gariepinus) were identified and characterized from the selected farms in Uganda. Gill and skin swabs were obtained from a total of 119 fish from 19 farms and were dissected aseptically to sample internal organs. The samples were inoculated onto Sheih media and incubated at 25°C for 48 hours. The suspected isolates were identified by colon characteristics, conventional biochemical tests and API 20 NE kits. The isolates were grouped into eight based on colon characteristic similarity. One isolate was selected per group for 16S rRNA gene sequencing and identified using the EZbiocloud.net ID software. Phylogenetic analysis of selected isolates was performed using the 16S rRNA gene sequences in BioEdit and MEGA 7.0.2 software. Basing on extrapolation of sequence analysis of the selected isolates, out of the 86 isolates, Myroides marinus was the most predominant species taking up 4 of the 8 groups (60 isolates) in 13 farms. The rest of the groups comprised of; Acinetobacter pitti, one group (6 isolates) in 6 farms, Chryseobacterium gambrini 2 groups (3 isolates) in 3 farms and one isolate was unidentified, in 3 farms. However, a total of 16 isolates did not grow on sub culturing. Phylogenetic analysis indicated that M. marinus isolates grouped with other M. marinus isolates from gene bank with significant intra-species diversity which was also observed with C. gambrini isolates. All the sampled farms had at least one isolate of a Flavobacterium from Tilapia and/or Catfish. Pathogenicity studies should be conducted on the isolates to establish their importance as fish pathogens and transmission dynamics so that an appropriate control measure can be recommended.
Effect of habitat disturbance on distribution and abundance of Papyrus endemic birds in Sio Port Swamp, Western Kenya
Authors: WANYONYI STELLAH NEKESA , MWANGI EVANS MUNGAI , GICHUKI NATHAN
Published: April 2020

Wanyonyi SN, Mwangi EM, Gichuki N. 2018. Effect of habitat disturbance on distribution and abundance of Papyrus endemic birds in Sio Port Swamp, Western Kenya. Bonorowo Wetlands 2: 49-60. Papyrus (Cyperus papyrus) swamps are found patchily around the shores of Lake Victoria mainly along river inflows. The objective of this study was to investigate the distinct forms of habitat disturbance and their implications on the distribution and abundance of papyrus endemic birds. Data on bird counts, habitat quality, and types of disturbance were collected for six months, from October 2013 to March 2014. Total bird counts were established using Timed Species Count (TSC) and playback call technique at every fixed point. The researcher waited for 1 minute, calls of the study species were played to elicit a response of the secretive papyrus endemic birds. The number of each bird's species seen or heard within a radius of 25 meters was recorded for the next 9 minutes before transferring to the next point count. Habitat quality such as height, density, and level of maturity was determined in 1 m2 plots along transverse transects. Opportunistic observations were made to establish forms of disturbance present during vegetation and bird surveys. Papyrus endemic birds were highly distributed in sites with pure papyrus (55.58%) than in places with mixed plants (44.42%). The abundance of three endemic birds, White-winged Swamp-warbler, Papyrus Gonolek, and Northern Brown-throated Weaver, was significantly different in mixed and pure papyrus sites. However, the abundance of Greater Swamp-warbler was not significantly different in mixed and pure papyrus sites in Sio Port Swamp during the study period. Forms of habitat disturbance established were vegetation clearing and invasion by terrestrial and aquatic plants. As many as 76.47% of papyrus vegetation were young and regenerated (0-2 m high), 19.65% were immature papyruses (2-4 m) whereas 3.88% were tall mature papyruses (4-6 m high). The abundance of papyrus endemic birds was positively and significantly correlated with the density of vegetation in height ranging from 4-6 m. Thus, any change in papyrus density changed the abundance of papyrus endemic birds. Advance management of papyrus clearing is necessary for the long-term conservation of biodiversity.
Short Communication: Diversity of mosquitoes in Central Java, Indonesia that act as new vector in various tropical diseases
Authors: KHARIRI KHARIRI
Published: April 2020

Khariri. 2018. Short Communication: Diversity of new mosquitoes in Central Java Province that can act as vector in various tropical diseases. Bonorowo Wetlands 2: 71-74. There are many diseases which are transmitted by mosquitoes as vectors. The presence of mosquitoes is widespread throughout the world including in Indonesia with an estimated 3100 species from 34 genera. Vector control is the main thing to do in addition to treatment in patients. Morphological identification of mosquitoes aims to identify the character and number of species so that it becomes a picture of diversity in an area. Data collection was carried out by collecting data from the 2015 Special Research Report on Vector and Reservoir Diseases (Rikhus Vektora) in Central Java Province. The data obtained were analyzed descriptively. Mosquito samples in Rikhus Vektora in 2015 in Central Java Province were collected from 3 different ecosystems, namely forest (H), non-forest (NH) and beach (P). The location of the ecosystem includes near settlements (DP) and far from settlements (JP). Mosquito samples were successfully identified as many as 29,071 tails consisting of 5 genera and 37 species. From Pekalongan, a sample of mosquitoes consisting of 5 genera and 19 species was obtained. As many as 4 species of mosquitoes are species that have never been identified and reported circulation in Pekalongan. Identification of mosquitoes collected in Purworejo has 5 genera and 23 species. Mosquito samples from Pati were identified as having 5 genera and 22 species.
Physicochemical properties and antioxidant activity of two varieties of apple cultivated in different areas in Morocco
Authors: Oussaid Driss , Mansouri Ismail , Laaroussi Hassan , Lyoussi Badiaa , El Aarabi Ilham
Published: April 2020

This study aimed to assess the effect of climate on the organoleptic qualities and phytochemical properties of two varieties of apple (Golden delicious (GD) and Red delicious (RD)) collected from different regions in Morocco. These two varieties of apple were examined for their bioactive compounds composition and antioxidant activity (in juice and different extracts). For physicochemical parameters, the highest acidity was observed in Golden delicious collected from station 1, which was the juiciest sample. Bioactive substances content was dependent on variety and station, while the highest polyphenol content was observed in Golden delicious collected from station 2 (135.41±6.66 mg GAE/100 mL of juice) and most top flavonoid content was observed in Red delicious collected from station 1 (7.43±0.13 mg QE/100 mL of juice). Furthermore, Red delicious collected from station 2 was the most effective in chelating the radical DPPH (IC50% = 0.92±0.01 µL of juice), and Red delicious collected from station 1 has the highest total antioxidant activity (2.47±0.02 mg AAE/100 mL of juice). The present work showed that the significant diversity in the different studied parameters of the apple cultivars was closely linked with the characteristics of the station, such as geography and climate.
Coherent narrow-linewidth optical frequency synthesis across the optical telecommunication band
Authors: Yang Honglei , Zhang Shengkang , Zhao Weinan , Zhang Li
Published: April 2020

Broadband, coherent narrow-linewidth optical frequency synthesis is of crucial importance in dual-comb interferometric measurement. Here we present a detailed description of the construction and performance characterization of a hertz-level linewidth coherent optical frequency synthesizer across the optical telecommunication band. A narrow-linewidth cavity-stabilized laser at 1565.00 nm is built and coherently transferred through a fiber link with an additional fractional frequency instability of

2.0

×

10

−
16

at 1 s averaging time. Broadband, coherent optical frequency synthesis is then achieved by steering one mode of a laser frequency comb with the transferred optical frequency oscillation. By beating with a 1542.14 nm ultra-stable cavity-stabilized laser, the evaluated fractional frequency stability and absolute linewidth of the nearest synthesized optical oscillation are

3.5

×

10

−
15

at 1 s averaging time and 1.8 Hz, respectively. According to the ultra-low-noise feature of the utilized laser frequency comb of

4.7

×

10

−
17

at 1 s averaging time, the synthesized optical frequency oscillations could maintain the high coherence across the comb’s output bandwidth.
Ultra-high resolution and broadband chip-scale speckle enhanced Fourier-transform spectrometer
Authors: Paudel Uttam , Rose Todd
Published: April 2020

Recent advancements in silicon photonics are enabling the development of chip-scale photonics devices for sensing and signal processing applications, among which on-chip spectrometers are of particular interest for precision wavelength monitoring and related applications. Most chip-scale spectrometers suffer from a resolution-bandwidth trade-off, thus limiting the uses of the device. Here we report on a novel passive, chip-scale, hybrid speckle-enhanced Fourier transform device that exhibits a two order-of-magnitude improvement in finesse (bandwidth/resolution) over the state-of-the art chip-scale speckle and Fourier transform spectrometers. In our proof-of-principle device, we demonstrate a spectral resolution of 140 MHz with 12-nm bandwidth for a finesse of 104 that can operate over a range of 1500-1600 nm. This chip-scale spectrometer structure implements a typical spatial heterodyne discrete Fourier transform interferometer network that is enhanced by speckle generated from the wafer substrate. This latter effect, which is extremely simple to invoke, superimposes the high wavelength resolution intrinsic to speckle generated from a strongly guiding waveguide with a more broadband but lower resolution discrete Fourier transform modality of the overarching waveguide structure. This hybrid approach signifies a new pathway for realizing chip-scale spectrometers capable of ultra-high resolution and broadband performance.
Unveil the time delay signature of optical chaos systems with a convolutional neural network
Authors: Chen Yetao , Xin Ronghuan , Cheng Mengfan , Gao Xiaojing , Li Shanshan , Shao Weidong , Deng Lei , Zhang Minming , Fu Songnian , Liu Deming
Published: April 2020

We propose a time delay signature extraction method for optical chaos systems based on a convolutional neural network. Through transforming the time delay signature of a one-dimensional time series into two-dimensional image features, the excellent ability of convolutional neural networks for image feature recognition is fully utilized. The effectiveness of the method is verified on chaos systems with opto-electronic feedback and all optical feedback. The recognition accuracy of the method is 100% under normal conditions. For the system with extremely strong nonlinearity, the accuracy can be 93.25%, and the amount of data required is less than traditional methods. Moreover, it is verified that the proposed method possesses a strong ability to withstand the effects of noise.
Measurement of the distance between two parallel precision apertures using time-of-flight method for cryogenic radiometry
Authors: Gan Haiyong , Liu Wende , Xu Nan , Li Jianwei , Wang Yangyang , Zhang Mingyu , He Yingwei , liu Xiangliang , Fu Yangting , Lin Yandong
Published: April 2020

Time-of-flight method was adopted to measure the distance between two parallel precision apertures utilized in a vacuum chamber for cryogenic radiometry. The diameters of the apertures are 9 mm and 8 mm, respectively. A 1550-nm femtosecond pulse laser, a 70-GHz photodetector, and a 30-GHz oscilloscope were used to measure the round-trip flight time difference between the flat front surfaces of the two precision apertures. The distance between the apertures was analyzed to be 0.36423 m with a relative standard uncertainty of 0.004%. The non-contact distance measurement method is useful for applications such as low background infrared radiance measurement system based on an absolute cryogenic radiometer.
Multi-scale sensorless adaptive optics: application to stimulated emission depletion microscopy
Authors: Antonello Jacopo , Barbotin Aurélien , Chong Ee Zhuan , Rittscher Jens , Booth Martin J.
Published: April 2020

Sensorless adaptive optics is commonly used to compensate specimen-induced aberrations in high-resolution fluorescence microscopy, but requires a bespoke approach to detect aberrations in different microscopy techniques, which hinders its widespread adoption. To overcome this limitation, we propose using wavelet analysis to quantify the loss of resolution due to the aberrations in microscope images. By examining the variations of the wavelet coefficients at different scales, we are able to establish a multi-valued image quality metric that can be successfully deployed in different microscopy techniques. To corroborate our arguments, we provide experimental verification of our method by performing aberration correction experiments in both confocal and STED microscopy using three different specimens.
Efficient full-color single-pixel imaging based on the human vision property—“giving in to the blues”
Authors: Qiu Ziheng , Zhang Zibang , Zhong Jingang
Published: April 2020

Single-pixel imaging is a novel, to the best of our knowledge, computational imaging scheme, but a large number of measurements are typically required in data acquisition. Full-color single-pixel imaging takes many more measurements than does monochromatic single-pixel imaging. Utilizing the fact that human eyes have a poorer spatial resolution to blues than reds and greens, we propose to sample the blue component of color images with an ultra-low sampling ratio so as to reduce the number of measurements. We demonstrate our method with simulations and experiments, concluding that 95% of the measurements can be reduced in the acquisition of the blue component of natural color images in the size of

256

×

256

pixels, and the resulting images are without remarkable visual loss. Moreover, utilizing the sparsity of natural images, the sampling ratios of the red and green components can be reduced to 15% and 50%, respectively. This Letter may generate a new insight of how to optimize the imaging efficiency by utilizing human vision properties. The proposed method can be adopted by other full-color computational imaging techniques.
When shot-noise-limited photodetectors disobey Poisson statistics
Authors: Rabinowitz Jacob , Rezaei Mohsen , Park Min-Su , Leong Tan Chee , Ulmer Melville , Mohseni Hooman
Published: April 2020

Photodetectors with internal gain are of great interest for imaging applications, since internal gain reduces the effective noise of readout electronics. High-gain photodetectors have been demonstrated, but only individually rather than as a full array in a camera. Consequently, there has been little investigation of the interaction between camera complementary metal oxide semiconductor (CMOS) electronics and the slow response time that high-gain photodetectors often exhibit. Here we show that this interaction filters shot noise and causes noise statistics to differ from the common Poisson distribution. As an example, we investigate a

320

×

256

array of InGaAs/InP high-gain phototransistors bonded to a CMOS readout chip. We demonstrate the filtering effects and discuss their consequences, including new (to the best of our knowledge) methods for extracting gain and increasing dynamic range.
Demonstration of using two aperture pairs combined with multiple-mode receivers and MIMO signal processing for enhanced tolerance to turbulence and misalignment in a 10  Gbit/s QPSK FSO link
Authors: Song Haoqian , Li Long , Pang Kai , Zhang Runzhou , Zou Kaiheng , Zhao Zhe , Du Jing , Song Hao , Liu Cong , Cao Yinwen , Willner Ari N. , Almaiman Ahmed , Bock Robert , Lynn Brittany , Tur Moshe , Willner Alan E.
Published: April 2020

We utilize aperture diversity combined with multiple-mode receivers and multiple-input-multiple-output (MIMO) digital signal processing (DSP) to demonstrate enhanced tolerance to atmospheric turbulence and spatial misalignment in a 10 Gbit/s quadrature-phase-shift-keyed (QPSK) free-space optical (FSO) link. Turbulence and misalignment could cause power coupling from the fundamental Gaussian mode into higher-order modes. Therefore, we detect power from multiple modes and use MIMO DSP to enhance the recovery of the original data. In our approach, (a) each of multiple transmitter apertures transmits a single fundamental Gaussian beam carrying the same data stream, (b) each of multiple receiver apertures detects the signals that are coupled from the fundamental Gaussian beams to multiple orbital angular momentum (OAM) modes, and (c) MIMO DSP is used to recover the data over multiple modes and receivers. Our simulation shows that the outage probability could be reduced from

>

0.1

to

<

0.01

. Moreover, we experimentally demonstrate the scheme by transmitting two fundamental Gaussian beams carrying the same data stream and recovering the signals on OAM modes 0 and

+

1

at each receiver aperture. We measure an up to

∼

10

d
B

power-penalty reduction for a bit error rate (BER) at the 7% forward error correction limit for a 10 Gbit/s QPSK signal.
Rapid acquisition of broadband two-dimensional electronic spectra by continuous scanning with conventional delay lines
Authors: Spencer Austin P. , Chen Lin X.
Published: April 2020

A passively phase-stable, broadband (

∼

7

f
s

,

>

2000

c
m

−
1

) two-dimensional (2D) electronic spectroscopy apparatus that achieves rapid acquisition rates by continuously—rather than step-wise—scanning the Fourier-transform dimension is demonstrated for the first time, to the best of our knowledge. This is made possible through use of a partially common path interferometer design in which the coherence time

τ

is sampled in a “rotating frame.” Rapid, continuous scanning of

τ

increases the duty cycle of signal collection, rejects the majority of excitation pulse scatter, and enables the measurement of a complete 2D spectrum in 92 ms, which minimizes the influence of pulse intensity and delay fluctuations on the 2D spectrum. In practice, these improvements make possible the acquisition of hundreds of 2D spectra in tens of minutes, which opens the door to dense sampling of ultrafast relaxation dynamics and to generating extremely broadband 3D Fourier-transform spectra.
Hybrid frequency-time spectrograph for the spectral measurement of the two-photon state
Authors: Xiang Xiao , Dong Ruifang , Quan Runai , Jin Yaqing , Yang Ye , Li Ming , Liu Tao , Zhang Shougang
Published: April 2020

In this Letter, a hybrid frequency-time spectrograph combining a tunable optical filter and a dispersive element is presented for measurement of the spectral properties of the two-photon state. In comparison with the previous single-photon spectrograph utilizing the dispersive Fourier transformation (DFT) technique, this method is advanced since it avoids the need for additional wavelength calibration and the electronic laser trigger for coincidence measurement; therefore, its application is extended to continuous wave (CW) pumped two-photon sources. The achievable precision of the spectrum measurement has also been discussed in theory and demonstrated experimentally with a CW pumped periodically poled lithium niobate (PPLN) waveguide-based spontaneous parametric down-conversion photon source. Such a device is expected to be a versatile tool for the characterization of the frequency entangled two-photon state.
Creating a three-dimensional surface with antireflective properties by using femtosecond-laser Bessel-beam-assisted thermal oxidation
Authors: Li Xiaowei , Xu Zhijie , Jiang Lan , Shi Yaoming , Wang Andong , Huang Lingling , Wei Qunshuo
Published: April 2020

Metal surfaces with low reflectance have received considerable attention for their great optical, electrical, and thermal properties. However, the difficulty in achieving low reflectance on curved metal surfaces has hindered their practical applications. We propose a rapid and flexible method for processing a three-dimensional surface with antireflective properties. A Bessel beam created using an axicon is employed to generate ripple structures on the curved surface, thereby assisting subsequent thermal oxidation. Ripple structures coated with oxide semiconductor nanowires are then processed on a Cu substrate, thus further reducing reflectance. Antireflective properties with a minimum reflectance of less than 0.015 at a wavelength of 500–1200 nm could be achieved by using this method. This presented approach reduces dimensionality in laser processing, subsequently improving processing efficiency, and provides a foundation for the practical application of metal antireflective surfaces.
Surface plasmon assisted control of hot-electron relaxation time
Authors: Memarzadeh Sarvenaz , Kim Jongbum , Aytac Yigit , Murphy Thomas E. , Munday Jeremy N.
Published: April 2020

Surface plasmon mediated hot-carrier generation is utilized widely for
the manipulation of electron–photon interactions in many types of
optoelectronic devices including solar cells, photodiodes, and optical
modulators. A diversity of plasmonic systems such as nanoparticles,
resonators, and waveguides has been introduced to enhance hot-carrier
generation; however, the impact of propagating surface plasmons on
hot-carrier lifetime has not been clearly demonstrated. Here, we
systematically study the hot-carrier relaxation in thin film gold (Au)
samples under surface plasmon coupling with the Kretschmann
configuration. We observe that the locally confined electric field at
the surface of the metal significantly affects the hot-carrier
distribution and electron temperature, which results in a slowing of
the hot electrons’ relaxation time, regardless of the average value of
the absorbed power in the Au thin film. This result could be extended
to other plasmonic nanostructures, enabling the control of hot-carrier
lifetimes throughout the optical frequency range.
Effect of mangosteen (Garcinia mangostana L.) peel extract as an antibiotic growth promoter on growth performance and antibiotic resistance in broilers
Authors: Herawati Okti , Untari Tri , Anggita Marla , Artanto Sidna
Published: April 2020

Background and Aim: Antibiotic resistance poses a risk to human health and has therefore been the focus of research. One of the causes of this resistance is the use of antibiotics as feed additives for animal nutrition. The development of antibiotic resistance in poultry through nutrition feed has drawn attention to the need for alternative antibiotic growth promoters (AGPs). Mangosteen (Garcinia mangostana L.), as a natural source of bioactive phytochemicals, is a potential AGP, but the effect of mangosteen-based treatment on antibiotic resistance in poultry has not been reported to date. Therefore, the aim of this study was to evaluate the effects of mangosteen peel extract as an AGP on body weight gain, feed conversion rate (FCR), and the antibiotic resistance in broilers. Materials and Methods: In this study, 30 1-day-old broiler chicks were divided into three groups. Group A (control) was not administered any treatment in the feed, Group B was treated with 0.3 g/kg colistin as the AGP in the feed, and Group C was treated with 2% mangosteen peel extract as the AGP in the feed; the treatments were administered for 30 days. The observed parameters included the effect of the treatments on body weight gain, feed intake, FCR, and the presentation of antibiotic resistance before and after the treatments (pre-treatment and post-treatment, respectively). Results: Post-treatment, the body weight gain, and feed intake in the broilers were not significantly different among all the groups; however, the body weight gain and FCR were significantly different between the control group and the treatment groups in the 3rd week of treatment and were not significantly different between Groups B and C. The rate of antibiotic resistance to chloramphenicol increased significantly by 40% in Group B post-treatment, but no such increase was observed in Groups A and C. Conclusion: The findings of our study indicate that compared with using colistin as an AGP using mangosteen peel extract as a natural AGP did not have any significantly different effect on body weight gain, feed intake, and FCR (p>0.05) but had a significantly different effect on the rate of antibiotic resistance in broilers (p<0.05). This study indicates the usefulness of mangosteen for improving the overall growth and production performance of broilers without increasing their antibiotic resistance.
Mediated Bordering
Authors: Ellebrecht Sabrina
Published: April 2020

The external border of the EU remains under permanent construction. Sabrina Ellebrecht engages with two of its primary building sites - the European Border Surveillance System (Eurosur) and the Refugee Boat. She analyzes how the function and quality of the EU's current political border is crafted, shaped, produced and eventually stabilized through these two mediators. Eurosur and the Refugee Boat mediate a level of Europeanization which has hitherto - and would otherwise have - been impossible. While Eurosur mobilizes the limits of border policing in various ways, the Refugee Boat functions as the vacillating European Other to legitimize both control and humanitarian interventions. The study shows the specific, if not constitutive, ambivalences of EU border policies, and explores the emergence of viapolitics.
Simplificação, acessibilidade textual e tradução em ambientes multilíngues
Authors: Paraguassu Liana , Finatto Maria José Bocorny
Published: April 2020

Este artigo sintetiza resultados de duas pesquisas sobre recursos de Educação a Distância (EaD) voltados para a formação de tradutores, realizadas com o apoio da Secretaria de Educação a Distância da Universidade Federal do Rio Grande do Sul (UFRGS) via Editais SEAD 24 e 25. Com a participação de alunos e de professores de disciplinas regulares de Tradução e Terminologia do curso de Letras-Bacharelado da UFRGS, as pesquisas trataram de: a) apresentar aos estudantes e professores os temas da complexidade textual, da simplificação e da acessibilidade terminológica em meio ao cenário atual da formação para a tradução profissional; b) demonstrar como esses temas podem ser explorados em contrastes multilíngues considerando a tradução, revisão e adaptação de textos de temática técnica-científica; c) propor e validar, via testagens, alternativas de atividades didáticas para apoiar a modalidade EaD em meio às atividades presenciais das disciplinas envolvidas. Os dados colhidos indicam os melhores perfis para atividades didáticas associadas aos temas em foco, em termos de recursos de EaD, assim como identificam eventuais problemas para o fluxo pedagógico, distinguindo pontos de maior ou de menor engajamento dos estudantes em torno da construção de suas competências e conhecimentos.