bluuebunny/crossref_metadata_2025 huggingface dataset:
Intratympanic injection of dexamethasone 4 mg/mL versus 10 mg/mL for management of idiopathic sudden sensorineural hearing loss
Authors: Shewel Yasser , Asal Samir I.
Published: June 2020

Background

The aim of this study was to determine whether different concentrations of intratympanic (IT) injection of dexamethasone at a dose of 4 and 10 mg/mL have an effect on hearing outcomes in patients with idiopathic sudden sensorineural hearing loss (ISSNHL).

Results

Our study was conducted on 30 adult patients with unilateral ISSNHL who failed to respond or with contraindications to systemic steroids. Patients were categorized into two groups; each one included 15 patients. IT injection of 4 mg/mL dexamethasone was done in one group (IT dexamethasone (Dex) 4 mg/mL), while 10 mg/mL dexamethasone was administered intratympanically in the other group (IT Dex 10 mg/mL). IT injection was performed twice weekly for two successive weeks. PTA thresholds were assessed at 0.5, 1, 2 and 4 kHz before and 1 month after the treatment.

In the group with IT Dex 10 mg/mL, the average PTA improved significantly from 75.50 ± 12.59 to 49 ± 24.04 dB with an average gain of 26.50 ± 14.25 (p = 0.0007). In the group with IT Dex 4 mg/mL, there was a significant change of PTA from a pretreatment value of 76.92 ± 11.89 dB to a post-treatment value of 59.27 ± 92.10 dB with an average gain of 17.65 ± 8.36 dB.

A comparison of the post-treatment gain of PTA in both groups showed better improvement of hearing in a group treated by IT Dex 10 mg/mL compared with 4 mg/mL.

Conclusion

This study demonstrated that IT injection of dexamethasone at a dose of 10 mg/ml was associated with better hearing outcomes compared with 4 mg/mL for the treatment of ISSNHL.
Vector-acoustic full-waveform inversion: Taking advantage of wavefield separation and dealiasing
Authors: Zheglova Polina , Malcolm Alison
Published: June 2020

Vector-acoustic full-waveform inversion (VAFWI) directly inverts vector-acoustic (VA) data, which consist of pressure and particle displacement components, at the cost of conventional acoustic full-waveform inversion (FWI). VA data contain information about the direction of arrival of the recorded seismic waves. In VAFWI, this directional information is taken into account by introducing an appropriate data weighting. With this weighting, in the geometry of a marine seismic experiment, the VAFWI adjoint calculation approximates inverse wavefield extrapolation, resulting in the natural separation of up- and downgoing recorded waves. If the free-surface effects are modeled during the inversion, the wave separation leads to (1) suppression of surface-related artifacts, (2) constructive interference of receiver ghosts with their primaries leading to preservation of the low-frequency content in the adjoint fields, and (3) compensation for insufficient spatial wavefield sampling on the receiver side. The horizontal displacement component helps interpolate the missing data. Synthetic examples demonstrate that for undersampled data, VAFWI consistently recovers the subsurface properties with higher resolution and fewer artifacts than conventional FWI.
Evaluating the Impact of Oncology Care Model Reporting Requirements on Biomarker Testing and Treatment
Authors: Castellanos Emily H. , Orlando Abigail , Ma Xinran , Parikh Ravi B. , O’Connell Gillian , Meropol Neal J. , Hamrick James , Adamson Blythe J. S.
Published: June 2020

PURPOSE:

The Oncology Care Model (OCM) is Medicare’s first alternative payment model program for patients with cancer. As of October 2017, participating practices were required to report biomarker testing of patients with advanced non–small-cell lung cancer (aNSCLC). Our objective was to evaluate the effect of this OCM reporting requirement on quality of care.

METHODS:

We selected patients with aNSCLC receiving care in practices in a nationwide de-identified electronic health record-derived database. We used an adjusted difference-in-differences (DID) logistic regression model to compare changes in biomarker testing rates (EGFR, ROS1, and ALK) and receipt of biomarker-guided therapy between patients in OCM versus non-OCM practices, before and after OCM implementation.

RESULTS:

The analysis included 14,048 patients from 45 OCM practices (n = 8,151) and 105 non-OCM practices (n = 5,897). The overall unadjusted rates for biomarker testing and receipt of biomarker-guided therapy increased over the study period (2011-2018) in both OCM (55.5% v 71.6%; 89.8% v 94.6%, respectively) and non-OCM (55.2% v 69.7%; 90.1% v 95.2%, respectively) practices. In the adjusted DID model, the rates of biomarker testing (odds ratio [OR], 1.09 [95% CI, 0.88 to 1.34]; P = .45) and receipt of biomarker-guided therapy (OR, 0.87 [95% CI, 0.52 to 1.45]; P = .58) were similar between OCM and non-OCM practices.

CONCLUSION:

OCM biomarker documentation and reporting requirements did not appear to increase the proportions of patients with aNSCLC who underwent testing or who received biomarker-guided therapy in OCM versus non-OCM practices.
Frustrated clathrin-mediated endocytosis – causes and possible functions
Authors: Baschieri Francesco , Porshneva Kseniia , Montagnac Guillaume
Published: June 2020

Clathrin-mediated endocytosis is the main entry route for most cell surface receptors and their ligands. It is regulated by clathrin-coated structures that are endowed with the ability to cluster receptors and to locally bend the plasma membrane, resulting in the formation of receptor-containing vesicles that bud into the cytoplasm. This canonical role of clathrin-coated structures has been shown to play a fundamental part in many different aspects of cell physiology. However, it has recently become clear that the ability of clathrin-coated structures to deform membranes can be perturbed. In addition to chemical or genetic alterations, numerous environmental conditions can physically prevent or slow down membrane bending and/or budding at clathrin-coated structures. The resulting ‘frustrated endocytosis’ is emerging as not merely a passive consequence, but one that actually fulfils some very specific and important cellular functions. In this Review, we provide an historical and defining perspective on frustrated endocytosis in the clathrin pathway of mammalian cells, before discussing its causes and highlighting the possible functional consequences in physiology and diseases.
The molecular chaperone Hsp90 regulates heterochromatin assembly through stabilizing multiple complexes in fission yeast
Authors: Sun Li , Liu Xiao-Min , Li Wen-Zhu , Yi Yuan-Yuan , He Xiangwei , Wang Yamei , Jin Quan-Wen
Published: June 2020

In the fission yeast Schizosaccharomyces pombe, both RNAi machinery and RNAi-independent factors mediate transcriptional and posttranscriptional silencing and heterochromatin formation. Here, we show that the silencing of reporter genes at major native heterochromatic loci (centromeres, telomeres, mating-type locus and rDNA regions) and an artificially induced heterochromatin locus is alleviated in a fission yeast hsp90 mutant, hsp90-G84C. Also, H3K9me2 enrichment at heterochromatin regions, especially at the mating-type locus and subtelomeres, is compromised, suggesting heterochromatin assembly defects. We further discovered that Hsp90 is required for stabilization or assembly of the RNA-induced transcriptional silencing (RITS) and Argonaute siRNA chaperone (ARC) RNAi effector complexes, the RNAi-independent factor Fft3, the shelterin complex subunit Poz1 and the Snf2/HDAC-containing repressor complex (SHREC). Our ChIP data suggest that Hsp90 regulates the efficient recruitment of the methyltransferase/ubiquitin ligase complex CLRC by shelterin to chromosome ends and targeting of the SHREC and Fft3 to mating type locus and/or rDNA region. Finally, our genetic analyses demonstrated that increased heterochromatin spreading restores silencing at subtelomeres in the hsp90-G84C mutant. Thus, this work uncovers a conserved factor critical for promoting RNAi-dependent and -independent heterochromatin assembly and gene silencing through stabilizing multiple effectors and effector complexes.
A half-century of innovation in technology—preparing MRI for the 21st century
Authors: Börnert Peter , Norris David G.
Published: June 2020

MRI developed during the last half-century from a very basic concept to an indispensable non-ionising medical imaging technique that has found broad application in diagnostics, therapy control and far beyond. Due to its excellent soft-tissue contrast and the huge variety of accessible tissue- and physiological-parameters, MRI is often preferred to other existing modalities. In the course of its development, MRI underwent many substantial transformations. From the beginning, starting as a proof of concept, much effort was expended to develop the appropriate basic scanning technology and methodology, and to establish the many clinical contrasts (e.g., T  1, T  2, flow, diffusion, water/fat, etc.) that MRI is famous for today. Beyond that, additional prominent innovations to the field have been parallel imaging and compressed sensing, leading to significant scanning time reductions, and the move towards higher static magnetic field strengths, which led to increased sensitivity and improved image quality. Improvements in workflow and the use of artificial intelligence are among many current trends seen in this field, paving the way for a broad use of MRI. The 125th anniversary of the BJR is a good point to reflect on all these changes and developments and to offer some slightly speculative ideas as to what the future may bring.
Analgesic efficacy of intravenous nefopam after spine surgery: a randomized, double-blind, placebo-controlled trial
Authors: Eiamcharoenwit Jatuporn , Chotisukarat Haruthai , Tainil Kanjana , Attanath Nalinrat , Akavipat Phuping
Published: June 2020

Background: The incidence of moderate to severe pain is high among patients undergoing spinal surgery. Nefopam can be used as an adjuvant analgesic postoperatively after spine surgery. The study aimed to assess the analgesic efficacy and side effects of nefopam on 24-hour postoperative morphine consumption after spine surgery.

Methods: The study is a randomized, double-blinded, placebo-controlled trial. A total of 96 patients were randomized into 4 treatment groups, 24 each. In group 1, patients received normal saline before surgical incision and before the end of surgery. In group 2, patients received 30 mg nefopam before surgical incision and normal saline before the end of surgery. In group 3, patients received normal saline before surgical incision and 30 mg of nefopam before the end of surgery. In group 4, patients received 30 mg of nefopam in both timings. Patient-controlled analgesia morphine was used for the postoperative period. Outcomes were to determine 24-hour morphine consumption and incidence of side effects. 

Results: Of 96 patients enrolled, 21 in placebo-placebo, 22 in nefopam-placebo, 22 in placebo-nefopam and 21 in nefopam-nefopam groups completed the study.  Analysis of the Kruskal-Wallis test on the intention-to-treat basis shows no significant difference in 24-hour postoperative morphine consumption between four groups, which were 18 [IQR 13.5-29], 20 [IQR 11-28.3], 17 [IQR 11.5-28.5], 13 [IQR 8.5-18.5] mg., respectively (p = 0.223). Incidence of side effects, including tachycardia, sedation, sweating and nausea/ vomiting, did not differ.

Conclusions: Adding perioperative nefopam to opioid analgesic does not improve analgesic efficacy in patients who underwent spine surgery.

Registration: Thai Clinical Trials Registry ID TCTR20171115001; registered on 15 November 2017.
Identifying the spatial patterning characteristics of HIV positive clients not linked to care using a geographic information system
Authors: Rombosia Kevin , Rangara Nelly , Oele Elizabeth , Kirui Nancy , Olaka Douglas , Ondura Evans , Mitto Bernard
Published: June 2020

Background: Linkage to care is a crucial early step in successful HIV treatment. This study sought to identify the spatial patterning characteristics of HIV positive clients that are not linked to care in the Kisumu West HIV program using a geographic information system.

Methods: The geocodes of HIV positive, non-linked clients’ residences were exported to ArcGIS software. The spatial patterning characteristics of HIV clients that are testing positive and not linked to care was described using Global Moran’s I statistic, which is a measure of spatial autocorrelation.

Results: A total of 14,077 clients were tested for HIV. Of clients testing positive for HIV, 10% (n=34) were not yet linked to care two weeks after the diagnosis of HIV. Of the HIV positive non-linked clients, most (65%; n= 32) had spatially identifiable data about where they resided. Regarding the spatial patterning characteristics of the clients who tested HIV positive but were not linked to care and with spatially identifiable residence information, the Global Moran I statistic for autocorrelation was 0.435 (z score 1.383, p- value 0.167).

Conclusion: By using age as an attribute value, the spatial distribution of clients testing HIV positive and not being linked to care is random. Geographical information systems can be used to identify the spatial patterning characteristics of HIV positive clients that are not linked to care. A key requirement to achieving this would require the collection of precise and accurate spatially identifiable locator information but without compromising patient confidentiality.
Case Report: Can we differentiate mesothelioma from inflammatory pericardial constriction preoperatively?
Authors: Raza Syed Shahmeer , Ullah Irfan , Awan Saira Kainat , Nadeem Muhammad Daniyal , Bashir Gulsam
Published: June 2020

Primary malignant pericardial mesothelioma (PMPM) is a rare cardiac tumor. The patient usually presents with pericardial constriction, usually misdiagnosed and wrongly managed. We present the case of a 21-year-old woman with a history of pericarditis and cardiac tamponade. The patient was referred from a clinic due to nausea, vomiting and ascites with lower extremity edema, soft and watery diarrhea, and right upper quadrant pain. Surgery (sternotomy and partial pericardiectomy) was proposed after looking at the different relevant investigations; it was not until that the patient was operated on that it was established that this wasn't a mere constriction but a malignancy. The patient shortly died after the operation. Pathology made a diagnosis of PMPM. Along with the classical symptoms those who present with level 1 thoracic adenopathy a decision to operate should be very carefully made, this may lead to a misdiagnosis of PMPM which postoperatively results in patient's death.
ExploreModelMatrix: Interactive exploration for improved understanding of design matrices and linear models in R
Authors: Soneson Charlotte , Marini Federico , Geier Florian , Love Michael I. , Stadler Michael B.
Published: June 2020

Linear and generalized linear models are used extensively in many scientiﬁc ﬁelds, to model observed data and as the basis for hypothesis tests. The use of such models requires speciﬁcation of a design matrix, and subsequent formulation of contrasts representing scientiﬁc hypotheses of interest. Proper execution of these steps requires a thorough understanding of the meaning of the individual coefﬁcients, and is a frequent source of uncertainty for end users. Here, we present an R/Bioconductor package, ExploreModelMatrix, which enables interactive exploration of design matrices and linear model diagnostics. Given a sample annotation table and a desired design formula, the package displays how the model coefﬁcients are combined to give the ﬁtted values for each combination of predictor variables, which allows users to both extract the interpretation of each individual coefﬁcient, and formulate desired linear contrasts. In addition, the interactive interface displays informative characteristics for the regular linear model corresponding to the provided design, such as variance inﬂation factors and the pseudoinverse of the design matrix.
Neuronal response variability as a product of divisive normalization; neurobiological implications at a macroscale level
Authors: Ruddy Kathy L. , Cole David M. , Simon Colin , Bächinger Marc T.
Published: June 2020

The occurrence of neuronal spikes recorded directly from sensory cortex is highly irregular within and between presentations of an invariant stimulus. The traditional solution has been to average responses across many trials. However, with this approach, response variability is downplayed as noise, so it is assumed that statistically controlling it will reveal the brain’s true response to a stimulus. A mounting body of evidence suggests that this approach is inadequate. For example, experiments show that response variability itself varies as a function of stimulus dimensions like contrast and state dimensions like attention. In other words, response variability has structure, is therefore potentially informative and should be incorporated into models which try to explain neural encoding. In this article we provide commentary on a recently published study by Coen-Cagli and Solomon that incorporates spike variability in a quantitative model, by explaining it as a function of divisive normalization. We consider the potential role of neural oscillations in this process as a potential bridge between the current microscale findings and response variability at the mesoscale/macroscale level.
Ambient and Indoor Air Pollution in Pregnancy and the risk of Low birth weight and Ensuing Effects in Infants (APPLE): A cohort study in Bangalore, South India
Authors: Shriyan Prafulla , Babu Giridhara R , Ravi Deepa , Ana Yamuna , van Schayck Onno CP , Thankachan Prashanth , Murthy GVS
Published: June 2020

Background: Exposure to air pollution (IAP) from the combustion of solid fuels is a significant cause of morbidity and mortality in developing countries. Pregnant women exposed to higher pollutant levels are at higher risk of delivering a low-birth-weight (LBW) baby. There is a lack of standardized data regarding the levels and types of specific pollutants and how they impact LBW. We aim to prospectively assess the association between ambient and indoor air pollution levels in pregnancy and low birth weight and understand the subsequent risk of adiposity in these infants.

Methods: We will conduct a prospective cohort study of 516 pregnant women recruited before 18 weeks of gestation in the urban slums of Bangalore, who have voluntarily consented to participate. We will estimate the level of air pollutants including particulate matter (<10 μm, <2.5 μm) and carbon monoxide (CO) parts per million (ppm) levels in both indoor and ambient environment. The follow-up of the delivered children will be done at delivery until the infant is one year old. The association between pollutants and LBW will be evaluated using logistic regression adjusting for potential confounders.Further, we will explore the mediation role of LBW in the hypothesized causal chain of air pollution and adiposity. Nested within a large cohort titled "Maternal Antecedents of Adiposity and Studying the Transgenerational role of Hyperglycemia and Insulin (MAASTHI)", we can estimate the absolute risk of having low birth weight caused by air pollution and other variables.

Discussion: Understanding the association between exposures to ambient and indoor air pollution and low birth weight is essential in India. LBW babies have a higher risk of developing obesity and Non-Communicable Diseases (NCDs) during adulthood. The results from this study can inform the efforts for controlling the air pollution-related chronic diseases in India.
La configuración de las políticas de migración circular en Sudamérica. Los acuerdos de regulación laboral de España con Colombia y Ecuador
Authors: Santi Silvana , Clavijo Janneth
Published: June 2020

Este trabajo indaga sobre el modo en que se conciben los procesos migratorios y los sujetos migrantes en la implementación del modelo de Migración Laboral Temporal y Circular (MLTD), en particular, en los acuerdos relativos a la regulación y ordenación de los flujos migratorios de España con Colombia y Ecuador (2001-2008), respectivamente. El texto se inscribe en una discusión más amplia acerca de la construcción del vínculo entre migración y desarrollo bajo la perspectiva de la gobernabilidad migratoria. Desde allí se abordan las nociones de cooperación, regularidad, (co)desarrollo y circularidad, como conceptos centrales que fundamentan la formulación y el desarrollo de estos programas. Para ello, optamos por un abordaje cualitativo a partir de la recopilación y análisis de un corpus documental que contempla diversos materiales institucionales. Los resultados muestran que los programas de MLTC forman parte de los mecanismos de control y gestión migratoria que se inscriben dentro de dinámicas políticas globales, regionales y nacionales. Enmarcados en la idea de una migración ordenada, los esquemas de mltc actúan como dispositivos asimétricos de impronta Norte-Sur, ofreciéndose como soluciones de beneficio mutuo para el desarrollo de las sociedades de origen, de destino y para los migrantes.
The Demotivating Effects of Communicating a Social-Political Stance: Field Experimental Evidence from an Online Labor Market Platform
Authors: Burbano Vanessa C.
Published: June 2020

Despite a recent surge in corporate activism, with firm leaders communicating about social-political issues unrelated to their core businesses, we know little about its strategic implications. This paper examines the effect of an employer communicating a stance about a social-political issue on employee motivation, using a two-phase, preregistered field experiment in an online labor market platform. Results demonstrate an asymmetric treatment effect of taking a stance depending on whether the employee agrees or disagrees with that stance. Namely, I observe a demotivating effect of taking a stance on a social-political issue with which employees disagree and no statistically significant motivating effect of taking a stance on a social-political issue with which employees agree. This study has important implications for the nascent scholarship on corporate activism, as well as the scholarship on strategic human capital management.

This paper was accepted by Greta Hsu, organizations.
E-learning in a new era: enablers and barriers to its implementation in nursing
Authors: Uprichard Kate
Published: June 2020

During these uncertain and unprecedented times, the use of technology has become paramount to staying connected to friends, family, work and society. Social distancing has forced a huge digital transformation to take place, and this will inevitably change the way we work, particularly within healthcare. One dramatic change is the reliance upon e-learning, which is now the preferred method of teaching and training. This article will explore both the benefits and barriers to e-learning, drawing upon the author's experience as a digital project nurse who aided with the implementation of e-learning for community nurses.
Aims, actions and advance care planning by district nurses providing palliative care: an ethnographic observational study
Authors: Walshe Catherine
Published: June 2020

District nurses are core providers of palliative care, yet little is known about the way that they provide care to people at home. This study aimed to investigate the role and practice of the district nurse in palliative care provision. This was an ethnographic study, with non-participant observation of district nurse-palliative care patient encounters, and post-observation interviews. District nurse teams from three geographical areas in northwest England participated. Data were analysed iteratively, facilitated by the use of NVivo, using techniques of constant comparison. Some 17 encounters were observed, with 23 post-observation interviews (11 with district nurses, 12 with patients/carers). Core themes were ‘planning for the future’ and ‘caring in the moment’. District nurses described how they provided and planned future care, but observations showed that this care focused on physical symptom management. District nurses engaged in friendly relationship building, which allows detailed management of symptomatology, but with little evidence of advance care planning.
Social prescribing: a ‘natural’ community-based solution
Authors: Howarth Michelle , Griffiths Alistair , da Silva Anna , Green Richard
Published: June 2020

This paper discusses social prescribing as part of the wider NHS England universal personalised care model, and it describes how community nurses can engage with social prescribing systems to support community resilience. A case study based on the example of gardening, as a nature-based social prescription provided by the RHS Bridgewater Wellbeing Garden, is provided to illustrate the scope, reach and impact of non-medical, salutogenic approaches for community practitioners. The authors argue that social prescribing and, in particular, nature-based solutions, such as gardening, can be used as a non-medical asset-based approach by all health professionals working in the community as a way to promote health and wellbeing. They consider how the negative impact of social distancing resulting from COVID-19 restrictions could be diluted through collaboration between a holistic, social prescribing system and community staff. The paper presents a unique perspective on how community nurses can collaborate with link workers through social prescribing to help combat social isolation and anxiety and support resilience.
Centroid drift of laser beam propagation through a water surface with wave turbulence
Authors: Li Jun , Luo Jianghua , Li Shangbin , Yuan Xiuhua
Published: June 2020

For underwater optical wireless communication (UOWC), the influence of waves close to the water’s surface cannot be ignored. We build an experimental system of UOWC in a laboratory environment, where two fans are employed to produce water waves to simulate the turbulent water surface. The propagation and scattering of the input light are experimentally investigated, which shows that the scattering depends on the intensity of the water surface wave as well as the depth of its turbulence. Although at the receiver the laser spots are random and chaotic, their centroid drifts present spatial dependence, which is then investigated from the statistical point of view. Such characteristics may provide guidance to the optimization of receiving, tracking, and aiming devices.
Velocity dependence of the performance of flowing-gas K DPAL with He and He/CH4 buffer gases: 3D CFD modeling and comparison with experimental results
Authors: Waichman Karol , Barmashenko Boris D. , Rosenwaks Salman
Published: June 2020

Accurate 3D computational fluid dynamics (CFD) modeling of flowing-gas
K DPAL is presented, taking into account ionization and ion–electron
recombination processes, ambipolar diffusion of K ions, and electron
heating. Whereas in a static K DPAL with He buffer gas, the neutral K
atoms in the lasing medium are depleted by these processes, the
depletion can be mitigated by application of gas flow. The lowest gas
velocity necessary for effective operation of a laser with He buffer
is

∼

500

m

/

s

, and is much higher than previously
estimated [Opt.
Express 25, 30793
(2017)OPEXFF1094-408710.1364/OE.25.030793]. The predictions of
the model for different

H
e

/

C
H

4

mixtures are presented and verified
by comparing them with experimental results obtained at the Air Force
Institute of Technology [“Kinetics of higher lying potassium states after excitation
of the D2 transition in the
presence of helium,” dissertation (Air Force Institute of
Technology, 2018)].
Proof-of-principle demonstration of compiled Shor’s algorithm using a quantum dot single-photon source
Authors: Duan Zhao-Chen , Li Jin-Peng , Qin Jian , Yu Ying , Huo Yong-Heng , Höfling Sven , Lu Chao-Yang , Liu Nai-Le , Chen Kai , Pan Jian-Wei
Published: June 2020

We report a proof-of-principle demonstration of Shor’s algorithm with photons generated by an on-demand semiconductor quantum dot single-photon source for the first time. A fully compiled version of Shor’s algorithm for factoring 15 has been accomplished with a significantly reduced resource requirement that employs the four-photon cluster state. Genuine multiparticle entanglement properties are confirmed to reveal the quantum character of the algorithm and circuit. The implementation realizes the Shor’s algorithm with deterministic photonic qubits, which opens new applications for cluster state beyond one-way quantum computing.
High-order harmonics generation in the plasmas produced on different rotating targets during ablation using 1 kHz and 100 kHz lasers
Authors: Boltaev Ganjaboy S. , Ganeev Rashid A. , Kim Vyacheslav V. , Abbasi Naveed A. , Iqbal Mazhar , Alnaser Ali S.
Published: June 2020

We analyze the high-order harmonics generation using 1 kHz and 100 kHz lasers by ablating different rotating targets. We demonstrate the high average flux of short-wavelength radiation using the latter laser, while comparing the plasma formation conditions at different pulse repetition rates. The analysis of harmonic stability in the case of the 100 kHz experiments showed the two-fold decay of the 27th harmonic generating in silver plasma after 3.5×106 shots. The advantages of shorter pulse–induced ablation for the improvement of harmonic generation stability are demonstrated. Two-color pump of plasma, resonance enhancement of single harmonic, and quasi-phase matching studies are presented for 1 kHz laser applications. The formation of modulated multi-jet plasma on the plane and curved surfaces during ablation by 100 kHz pulses is demonstrated. In the case of the 25th harmonic of 1030 nm radiation (E=30 eV) generated during experiments in carbon plasma, at 100 kHz and 40 W average power of driving pulses, 0.4 mW of average power for single harmonic in the 40 nm spectral range was achieved.
Unusual spin and angular momentum of Dyakonov waves at the hyperbolic-material surface
Authors: Zhang Yuqi , Wang Xiangguang , Zhang Dezhi , Fu Shufang , Zhou Sheng , Wang Xuan-Zhang
Published: June 2020

Three Dyakonov-like polaritons (DLPs) exist at the interface between a hyperbolic material (HM) and a covering medium (CM). Each DLP is a hybridized-polarization surface polariton composed of two evanescent waves on both sides of the interface. We investigated their spin and angular momentum. We analytically found that any DLP carries two spins producing mutually orthogonal spin angular-momentum (SAM) components. The spins and angular-momentum have different features on both sides of the interface, and further differences among the three DLPs are very obvious. For the interface structure formed by hexagonal boron nitride (hBN) and air, the SAM mainly distributes in the air for DLP-I, the SAM is approximately transverse to the propagating direction for DLP-II, and it is surprisingly large in the hBN for DLP-III and can reach several ten times that in the usual situation. There is the spin-k locking for every DLP, but the spin-k locking is different for different DLPs. These properties do not exist for traditional surface polaritons or ordinary evanescent waves. The above unique results can support some potential applications in the fields of nano- and micro-photonics, optoelectronics and mechanics, as well as relevant technologies.
Symmetric carrier assisted differential detection receiver with low-complexity signal-signal beating interference mitigation
Authors: Zhu Yixiao , Li Longsheng , Fu Yan , Hu Weisheng
Published: June 2020

Low-cost, spectrally efficient self-coherent detection capable of optical field recovery is desired for inter-data center connections and metro networks. In this work, a simplified symmetric carrier assisted differential detection (S-CADD) receiver structure is proposed, which removes the single-ended photodiode branch and saves one ADC in standard asymmetric CADD (A-CADD) receivers. To compensate for the signal-signal beating (SSBI) impairment, a low-complexity iterative SSBI mitigation algorithm is put forward as well. The computational complexity is reduced by moving equalization, de-modulation and modulation out of each iteration. Based on single-carrier twin-single sideband (SSB) pulse- and quadrature-amplitude modulation (PAM and QAM) signals, the OSNR sensitivity with different carrier-to-signal power ratios (CSPRs) at back-to-back (BTB) scenario, the bit-error rates (BER) performance after 1000km fiber transmission, and the received optical power sensitivity at BTB are theoretically and numerically compared for both S-CADD and A-CADD receivers, respectively.
Multi-line FLEET by imaging periodic masks
Authors: Zhang Yibin , Marshall Garrett , Beresh Steven J. , Richardson Daniel , Casper Katya M.
Published: June 2020

A simple linear configuration for multi-line femtosecond laser electronic excitation tagging (FLEET) velocimetry is used for the first time, to the best of our knowledge, to image an overexpanded unsteady supersonic jet. The FLEET lines are spaced 0.5–1.0 mm apart, and up to six lines can be used simultaneously to visualize the flowfield. These lines are created using periodic masks, despite the mask blocking 25%–30% of the 10 mJ incident beam. Maps of mean single-component velocity in the direction along the principal flow axis, and turbulence intensity in that same direction, are created using multi-line FLEET, and computed velocities agree well with those obtained from single-line (traditional) FLEET. Compared to traditional FLEET, multi-line FLEET offers increased simultaneous spatial coverage and the ability to produce spatial correlations in the streamwise direction. This FLEET permutation is especially well suited for short-duration test facilities.
2.05  µm chirped pulse amplification system at a 1  kHz repetition rate—2.4  ps pulses with 17  GW peak power
Authors: von Grafenstein Lorenz , Bock Martin , Ueberschaer Dennis , Koç Azize , Griebner Uwe , Elsaesser Thomas
Published: June 2020

Ho-doped yttrium lithium fluoride chirped pulse amplification (CPA) is
implemented with a high-gain regenerative amplifier (RA) and a
two-stage booster amplifier. We demonstrate the generation of 52.5 mJ
pulses with a duration of 2.4 ps at a 1 kHz repetition rate. A peak
power of 17 GW is achieved for the 2050 nm pulses. The CPA displays a
remarkably high stability with a pulse-to-pulse rms as low as 0.23%.
The RA operates without any signs of bifurcation and delivers 12 mJ
pulses. Seeding the booster amplifier with the RA output scales the
pulse energy linearly up into the 50–60 mJ range. The amplifier system
is operated at room temperature and shows a high optical-to-optical
efficiency of 20.3% with respect to the optical pump power.
Optofluidic waveguide bending by thermal diffusion for visible light control
Authors: Zuo Yunfeng , Liu Hailiang , Yang Yi
Published: June 2020

Optofluidics has inspired many promising optical devices. Among them, waveguide bending is an important element for guiding light. Here, we demonstrated the thermal-diffusion liquids, acting as a natural transformation optical material in an annular structure. Compared with conventional step-index waveguide bending, this thermal one enables real-time tunable visible light bends by extreme angles, with nearly no power loss and intensity distribution. This unique light bending is because gradient refractive-index profiles caused by thermal diffusion meet the requirements by transformation optics. The work demonstrates the thermal diffusion in liquids as a natural technology to realize optofluidic gradient-index designs and has potential for tunable optical systems.
Experimental demonstration of mid-IR absorption enhancement in single layer CVD graphene
Authors: Nematpour Abedin , Lisi Nicola , Chierchia Rosa , Grilli Maria Luisa
Published: June 2020

Mid-IR absorption of single layer graphene (SLG) was simulated and experimentally demonstrated by embedding a SLG grown by chemical vapor deposition (CVD) inside a Fabry–Perot (FP) filter made by alternating quarter wave Si and

S
i

O

2

layers fabricated by radiofrequency sputtering. The absorption from the graphene layer was modeled by using COMSOL Multiphysics in four different configurations, depending on its position inside the filter, an asymmetric FP made of two different dielectric mirrors separated by a cavity. In the first three configurations, graphene was inserted at the center of the optical cavity and inside the top or bottom dielectric mirror forming the FP. The fourth configuration involves two layers of graphene, each positioned inside one of the dielectric mirrors. The calculated electric field distribution inside the FP shows two symmetric maxima just above and below the cavity, i.e., inside the mirrors, while the electric field at the center of the cavity is negligible. For the experimental demonstration, the graphene geometry corresponding to the maximum electric field intensity was chosen, and, between two equivalent alternatives, the one with the easiest fabrication procedure was selected. Results demonstrate a maximum experimental absorption of 50% at 4342 nm for SLG when inserted in the top mirror of the FP, in excellent agreement with the simulated value of 53%.
Improved refractive-index sensing performance in medium contrast gratings by asymmetry engineering
Authors: Vyas Hardik , Hegde Ravi S.
Published: June 2020

Silicon nitride (Si3N4) subwavelength medium contrast gratings (MCGs) directly integrated with CMOS photodetectors are a promising option for on-chip label-free biosensing. The narrow spectral features required for sensing are often realized in Si3N4 nanostructures by weakly corrugated gratings which limit design flexibility. We numerically investigate the optical properties of asymmetry-engineered MCG gratings and predict the formation of ultra-sharp spectral features via the excitation of quasi-bound states in continuum (QBIC) resonances. Systematic investigation of the design parameter space shows that sharp spectral features are obtained for a wide range of parameters without requiring ultrathin grating profiles. Transmission-mode refractive index sensing simulations for bulk and surface sensing, considering both wavelength-shift and intensity-shift modalities, indicate performance gains using these structures.
All-fiber generation of arbitrary cylindrical vector beams on the first-order Poincaré sphere
Authors: Feng Lipeng , Li Yan , Wu Sihan , Guan Xun , Yang Chen , Tong Weijun , Li Wei , Qiu Jifang , Hong Xiaobin , Zuo Yong , Guo Hongxiang , Chen Erhu , Wu Jian
Published: June 2020

We propose a linear mapping relationship between the polarization of the fundamental mode and the cylindrical vector (CV) modes on the first-order Poincaré sphere (FOPS) in fiber. The new method is based on the four-dimensional complex Jones matrices in terms of the linearly polarized mode bases. With our theoretical model, an all-fiber approach to generate arbitrary CV beams on the FOPS is proposed theoretically and verified experimentally. In the experiment, through the combination of a mode converter and a two-segment cascaded few-mode fiber with fixed stresses, it is possible to generate all CV modes on the FOPS by only adjusting the polarization of the fundamental mode. The Stokes parameters of the output light are measured to verify our scheme, which shows good agreement with the theoretical prediction. The method may provide a convenient way to generate CV beams and evolve the polarization states in any path on the FOPS, which is expected to have potential applications in encoding information and quantum computation.
Pulse-width-induced polarization enhancement of optically pumped N-V electron spin in diamond
Authors: Song Yumeng , Tian Yu , Hu Zhiyi , Zhou Feifei , Xing Tengteng , Lu Dawei , Chen Bing , Wang Ya , Xu Nanyang , Du Jiangfeng
Published: June 2020

The nitrogen-vacancy (N-V) center in diamond is a widely used platform for quantum information processing and sensing. The electron-spin state of the N-V center could be initialized, read out optically, and manipulated by resonate microwave fields. In this work, we analyze the dependence of electron-spin initialization on widths of laser pulses. We build a numerical model to simulate this process and to verify the simulation results in experiments. Both simulations and experiments reveal that shorter laser pulses are helpful to the electron-spin polarization. We therefore propose to use extremely short laser pulses for electron-spin initialization. In this new scheme, the spin-state contrast could be improved about 10% in experiments by using laser pulses as short as 4 ns in width. Furthermore, we provide a mechanism to explain this effect, which is due to the occupation time in the meta-stable spin-singlet states of the N-V center. Our new scheme is applicable in a broad range of N-V-based applications in the future.
Between ‘filter bubbles’ and community leaders: An exploratory study of Facebook groups for Russophones/Russians in the Netherlands
Authors: Gabdulhakov Rashid , Trottier Daniel
Published: June 2020

Through an exploration of Facebook groups designed for Russophones and Russians in the Netherlands, this study considers online community belonging negotiations. In doing so, the article aims to address the role of online administrators (admins) in online community construction, seeking to enrich the algorithm-centric literature covering customized feeds. The authors argue that by moderating discussions, approving and banning users, and setting the agenda more generally in the online environments that they create and manage, admins acquire and perform functions that may surpass or compliment algorithmic biases.
Population structure of Annona coriacea Mart. (Annonaceae) in different Cerrado phytophysiognomies
Authors: Silva Patrícia Oliveira da , Valente Jessica Barros Cabral , Silva Patricia Lacerda , Gomes Carolina Ferreira , Menino Gisele Cristina de Oliveira
Published: June 2020

Knowing the regeneration and structure of a species in different phytophysiognomies is extremely important to understand its pattern of occurrence. In spite of its importance, this type of study is still scarce in the Cerrado biome. In this perspective, this work aimed to compare the structure of the arboreal and regenerating strata of Annona coriacea in the cerrado sensu stricto and in the cerradão (savanna woodland). For that purpose, 13 plots of 400m² were installed in each physiognomy. All individuals of A. coriacea were sampled and had their diameter and height measured. The individuals were divided into regenerating and arboreal and were distributed in classes of height and diameter. Furthermore, the absolute density and the basal area of each extract were calculated in each physiognomy. The parameters were compared using the T-test. In total, 130 individuals of A. Coriacea were sampled, with 42 regenerating individuals in the cerrado sensu stricto and 49 in the cerradão. As for the arboreal individuals, 33 were sampled in the cerrado sensu stricto and 6 in the cerradão. All evaluated parameters revealed to be significantly different for the physiognomies. Based on these results, it is possible to affirm that A. coriacea did not present a distribution pattern in the two physiognomies, although it presents a better establishment success in the cerrado sensu stricto. In the cerradão, although the seeds can germinate, the seedlings fail to develop and reach the adult age.
Lipase Elevation in Patients With COVID-19
Authors: McNabb-Baltar Julia , Jin David X. , Grover Amit S. , Redd Walker D. , Zhou Joyce C. , Hathorn Kelly E. , McCarty Thomas R. , Bazarbashi Ahmad N. , Shen Lin , Chan Walter W.
Published: June 2020

INTRODUCTION:

Although coronavirus disease (COVID-19) has been associated with gastrointestinal manifestations, its effect on the pancreas remains unclear. We aimed to assess the frequency and characteristics of hyperlipasemia in patients with COVID-19.

METHODS:

A retrospective cohort study of hospitalized patients across 6 US centers with COVID-19.

RESULTS:

Of 71 patients, 9 (12.1%) developed hyperlipasemia, with 2 (2.8%) greater than 3 times upper limit of normal. No patient developed acute pancreatitis. Hyperlipasemia was not associated with poor outcomes or symptoms.

DISCUSSION:

Although a mild elevation in serum lipase was observed in some patients with COVID-19, clinical acute pancreatitis was not seen.
Reformas educacionais e reconfiguração da universidade / Educational reforms and university reconfiguration
Authors: Silva Sarita Medina , Andrade Luiza Vitória Vital
Published: June 2020

Este artigo tem por objetivo contextualizar o ensino superior evidenciando a conjuntura política educacional que reconfigurou a universidade brasileira a partir da década de 1990. Nesse sentido, foi apresentado um breve percurso do processo de desenvolvimento das políticas públicas educacionais que envolvem a reconfiguração da universidade e a democratização do acesso proposto pelas políticas de expansão do ensino superior, considerando as contradições quanto à proposição de avanços e os retrocessos. Assim, a finalidade deste texto é situar a dinâmica atual do funcionamento das universidades federais.
La teoría evolutiva como solución al control de formación
Authors: Guzmán Hernández Sandra Milena , Mojica-Nava Eduardo
Published: June 2020

Se presenta un control de formación para múltiples Vehículos Submarinos Autónomos con estructura de tipo líder-seguidor. El controlador se modela como un sistema multi-agente representado por un dígrafo compuesto por vértices y artistas que simbolizan los agentes (vehículos) y el sistema de comunicación, respectivamente. Se empleó la matriz Laplaciana compleja del dígrafo, para calcular la formación geométrica y enseguida se evalúa la respuesta de consenso de la formación utilizando la teoría evolutiva dinámica del replicador mutador. Finalmente, se integran las dos respuestas y se calcula la posición de cada agente seguidor. Las simulaciones muestran que combinando estas dos teorías se puede garantizar una perfecta formación geométrica en todo momento y que se pueden emplear un sinnúmero de agentes en la estructura.
Fuerzas g percibidas en ciudadanos bogotanos al transportarse
Authors: Navarro Núñez Huber , Córdoba Cristancho Gilbert Olvey , Montaña Quintero Henry
Published: June 2020

La movilidad en la ciudad de Bogotá D.C. se encuentra condicionada por factores resultantes de las actividades cotidianas de sus habitantes. Según la Encuesta de Movilidad 2011, la participación modal total de viajes por persona fue así: caminando 46%, transporte público 30% (público colectivo 20%, Transmilenio 9%, intermunicipal 1%), automóvil 10%, taxi 4%, motocicleta 2%, bicicleta 3%, informal 1%, y otros 4%. Ante esta dinámica, se requiere observar la proporción de fuerzas acelerométricas (Fuerzas G), a la que se expone una persona que se moviliza en estos medios de transporte, cuando son generadas de manera involuntaria por: repentinos cambios de velocidad, imperfecciones en la vía, entre otros factores. Con el fin de recolectar esa información, el presente artículo describe la investigación que condujo a la implementación de un prototipo para tal propósito. Se exhiben los resultados de las pruebas variando el medio, la posición del sensor y la ruta estimada.
Arquitectura software para gestionar licencias ambientales en explotación petrolera
Authors: Rodríguez Cárdenas Daniel , Barón Velandia Julio , Bolaños  Castro Sandro Javier
Published: June 2020

Las actividades de minería en Colombia se hallan subordinadas al cuidado ambiental y a la mitigación de los efectos adversos que se puedan generar sobre las comunidades y el ambiente, por lo tanto, antes de ejecutar obras civiles de exploración y explotación petrolera, se debe obtener una licencia ambiental. En este artículo se presenta la propuesta de arquitectura software que permite compartir en forma integrada información en coordenadas geográficas ajustadas a la normatividad vigente, para apoyar la toma de decisión de: especialistas, entidades de control y comunidades, involucradas en el estudio, evaluación y aprobación de licencias ambientales. Se describen las pautas seguidas en la obtención del diseño basado en componentes para facilitar la flexibilidad y escalabilidad de las diferentes funcionalidades, que deben ser soportadas para integrar información de diferentes fuentes y formatos.