bluuebunny/crossref_metadata_2025 huggingface dataset:
Aerobic Fitness Is Related to Myocardial Fibrosis Post–Anthracycline Therapy
Authors: Kirkham Amy Ashley , Paterson D. Ian , Haykowsky Mark J. , Beaudry Rhys I. , Mackey John R. , Pituskin Edith , Grenier Justin G. , Thompson Richard B.
Published: August 2020

Adjuvant anthracycline chemotherapy for breast cancer is associated with cardiotoxicity and reduced cardiorespiratory fitness (V˙O2peak).

Purpose

We evaluated the impact of anthracyclines on left ventricular function and myocardial tissue characteristics using cardiovascular magnetic resonance (CMR) imaging to determine their relationship with V˙O2peak.

Methods

Women with breast cancer who had not yet received treatment (No-AT, n = 16) and had received anthracycline treatment ~1 yr earlier (Post-AT, n = 16) and controls without cancer (CON, n = 16) performed a maximal exercise test and a comprehensive 3T CMR examination, including native myocardial T
1 mapping, where elevated T
1 times are indicative of myocardial fibrosis. ANOVA and linear regression were used to compare CMR variables between groups and to determine associations with V˙O2peak. Subgroup analysis was performed by categorizing participants as “fit” or “unfit” based on whether their V˙O2peak value was greater or less than 100% of reference value for age, respectively.

Results

Left ventricular end-diastolic volume, ejection fraction, and mass were similar between groups. Post-AT, T
1 times were elevated (1534 ± 32 vs 1503 ± 28 ms, P < 0.01), and V˙O2peak was reduced (23.1 ± 7.5 vs 29.5 ± 7.7 mL·kg−1⋅min−1, P = 0.02) compared with CON. In No-AT, T
1 times and V˙O2peak were similar to CON. In the Post-AT group, T
1 time was associated with V˙O2peak (R
2 = 64%), whereas in the absence of anthracyclines (i.e., No-AT and CON groups), T
1 time was not associated with V˙O2peak. Regardless of group, all fit women had similar T
1 times, whereas unfit women Post-AT had higher T
1 than unfit CON (1546 ± 22 vs 1500 ± 33 ms, P < 0.01).

Conclusions

After anthracycline chemotherapy, an elevated T
1 time suggesting greater extent of myocardial fibrosis, was associated with lower V˙O2peak. However, those who were fit did not have evidence of myocardial fibrosis after anthracycline treatment.
Critical Speed throughout Aging: Insight into the World Masters Championships
Authors: GIFFORD JAYSON R. , COLLINS JESSICA
Published: August 2020

Purpose

This study aimed to determine how the speed–distance relationship, described by critical speed (CS) and distance prime (D′), is altered with aging.

Methods

Official race data from the past eight World Masters Athletics Indoor Track and Field World Championships were used for this study. CS and D′ were calculated for female and male athletes (35–90 yr of age) who registered times for the 800-, 1500-, and 3000-m runs during a single championship to determine the relationship between age and CS and D′. Twenty-six athletes completed sufficient races in multiple championships to retrospectively assess the change in CS and D′ over time.

Results

Cross-sectional data indicated that CS continuously decreases after age 35 yr in a curvilinear manner with advancing age (R
2 = 0.73, P < 0.001, n = 187), with even greater decreases in CS occurring after ~70 yr of age. D′ also changed in a curvilinear manner with age (R
2 = 0.45, P < 0.001, n = 103), such that decreases were observed between 35 and 70 yr, followed by an increase in D′ thereafter. Retrospective, longitudinal data, with an average follow-up of 6.38 ± 1.73 yr, support these findings, indicating that the annual decrease in CS grows with advancing age (e.g., ~1% vs ~3% annual decrease in CS at age 55 vs 80 yr, respectively) and that D′ shifts from an annual decrease (e.g., ~2.5% annual decrease at 55 yr) to an annual increase (e.g., ~2.5% annual increase at 80 yr) around 70 yr of age. Importantly, the relationship between CS and race pace was unaffected by age, supporting the relevance of CS throughout aging.

Conclusion

Even among world-class athletes, CS decreases and D′ changes with aging. These adaptations may contribute to the diminished exercise ability associated with aging.
Stereotactic body radiotherapy (SBRT) in metachronous oligometastatic prostate cancer: a systematic review and meta-analysis on the current prospective evidence
Authors: Yan Michael , Moideen Nikitha , Bratti Vanessa Freitas , Moraes Fabio Ynoe de
Published: August 2020

Objective:

In contrast to traditional views of incurability, patients with oligometastatic disease present with an opportunity for disease eradication with aggressive treatment. There is mounting evidence in support of the role of stereotactic body radiotherapy (SBRT) in oligometastatic prostate cancer (OMPC).

Methods:

MEDLINE and EMBASE were queried for prospective cohort studies reporting the outcomes of metachronous OMPC treated with SBRT. The primary outcome was overall local control. Secondary outcomes included androgen deprivation therapy-free survival (ADTFS), biochemical recurrence free survival (BCFS), and progression-free survival (PFS). When appropriate, these endpoints were combined in a meta-analysis.

Results:

We screened 356 abstracts and identified 10 studies to include in our analysis, with a total of 653 patients and 1,111 lesions. The maximum number of lesions included in any single study ranged from 3 to 5. PET-CT staging occurred in 92.4% of all patients. SBRT dose varied, with BED1.5 ranging from 152 to 408. Only one Grade 3 bone toxicity was observed. Meta-analysis reported an overall local control rate of 97% (95% CI, 94–100). Median ADTFS was 24.7 months (95% CI, 20.1–29.2 months). Two-year BCFS, PFS, and ADTFS were 33% (95% CI, 11–55), 39% (95% CI, 24–54), and 52% (95%CI, 41–62), respectively. Patients treated with SBRT were half as likely to experience PSA progression than those on observation when looking at randomized control trial data alone.

Conclusion:

SBRT appears to be effective in controlling overall disease burden in metachronous OMPC patients and is associated with minimal significant toxicity. The current prospective literature is scarce, and further prospective data are needed to guide treatment recommendations.

Advances in knowledge:

This study provides a comprehensive summary of the prospective evidence reporting the outcomes of SBRT in the management of OMPC patients. We quantify the rates of local control, biochemical-free recurrence, progression-free survival, and ADT-free survival through meta-analysis.
Image-guided interstitial brachytherapy boost for keratinizing squamous cell carcinoma of inferior wall of the nasopharynx
Authors: Murakami Naoya , Yoshimoto Seiichi , Uematsu Masakazu , Kashihara Tairo , Takahashi Kana , Inaba Koji , Okuma Kae , Igaki Hiroshi , Nakayama Yuko , Masui Koji , Yoshida Ken , Itami Jun
Published: August 2020

High-dose-rate interstitial brachytherapy (HDR-ISBT) is relatively rarely applied for the head and neck cancer because of its anatomical complexity and difficulty of applicator placement. However, its dose distribution is more confined even better than intensity-modulated radiation therapy (IMRT) and can deliver a higher dose while sparing surrounding normal tissues. In this case report, the effectiveness of HDR-ISBT as a boost following IMRT for keratinizing squamous cell carcinoma of nasopharynx was presented. A 76-year-old female who suffered from cT3N0M0 keratinizing squamous cell carcinoma of the nasopharynx was treated with definitive concurrent chemoradiation therapy involving IMRT. However, physical examination and laryngoscope fibre finding showed evident residual tumour at 60 Gy of IMRT, then, boost HDR-ISBT was proposed. After delivering 66 Gy of IMRT, CT image-guided HDR-ISBT 4 Gy in a single fraction was performed under local anaesthesia and sedation. MRI taken 5 months after HDR-ISBT showed remarkable shrinkage of the primary tumour. After HDR-ISBT, the remaining session of IMRT was delivered from the next day until 70 Gy in 35 fractions. It was demonstrated that boost HDR-ISBT combined with IMRT for keratinizing squamous cell carcinoma of the nasopharynx was performed safely and showed favourable efficacy.
Comparison of chest X-ray interpretation by Emergency Department clinicians and radiologists in suspected COVID-19 infection: a retrospective cohort study
Authors: Kemp Oliver J , Watson Daniel J , Swanson-Low Carla L , Cameron James A , Von Vopelius-Feldt Johannes
Published: August 2020

Objectives:

We describe the inter-rater agreement between Emergency Department (ED) clinicians and reporting radiologists in the interpretation of chest X-rays (CXRs) in patients presenting to ED with suspected COVID-19.

Methods:

We undertook a retrospective cohort study of patients with suspected COVID-19. We compared ED clinicians’ and radiologists’ interpretation of the CXRs according to British Society of Thoracic Imaging (BSTI) guidelines, using the area under the receiver operator curve (ROC area).

Results:

CXRs of 152 cases with suspected COVID-19 infection were included. Sensitivity and specificity for ‘classic’ COVID-19 CXR findings reported by ED clinician was 84 and 83%, respectively, with a ROC area of 0.84 (95%CI 0.77 to 0.90). Accuracy improved with ED clinicians’ experience, with ROC areas of 0.73 (95%CI 0.45 to 1.00), 0.81 (95%CI 0.73 to 0.89), 1.00 (95%CI 1.00 to 1.00) and 0.90 (95%CI 0.70 to 1.00) for foundation year doctors, senior house officers, higher speciality trainees and ED consultants, respectively (p < 0.001).

Conclusions:

ED clinicians demonstrated moderate inter-rater agreement with reporting radiologists according to the BSTI COVID-19 classifications. The improvement in accuracy with ED clinician experience suggests training of junior ED clinicians in the interpretation of COVID-19 related CXRs might be beneficial. Large-scale survey studies might be useful in the further evaluation of this topic.

Advances in knowledge:

This is the first study to examine inter-rater agreement between ED clinicians and radiologists in regards to COVID-19 CXR interpretation. Further service configurations such as 24-hr hot reporting of CXRs can be guided by these data, as well as an ongoing, nationwide follow-up study.
Point of care lung ultrasound in COVID-19: hype or hope?
Authors: Alfuraih Abdulrahman M.
Published: August 2020

The COVID-19 coronavirus pandemic has critically struck the world economy and healthcare systems. The highly contagious virus spreads rapidly and can result in potentially life-threatening acute respiratory distress. The current established test for diagnosing COVID-19 is using the RT-PCR laboratory test. However, the test requires specialized laboratories and testing kits. Recent reports also showed high false-negative rates. Experts recognize the urgent need to develop a rapid point of care diagnostic tests. Ultrasonography is a widely established safe diagnostic imaging test for detecting various lung abnormalities. Recent publications from China and Italy provided limited evidence on its usefulness for diagnosing COVID-19 in emergency departments earlier than RT-PCR. Ultrasound is sensitive to pleural and subpleural abnormalities, which suggests a great potential diagnostic role given the predilection for COVID-19 in peripheral subpleural regions.This paper reviews the current evidence and discusses the problems with specificity and scoring.
Effects of rapid recruitment and dissemination on Covid-19 mortality: the RECOVERY trial
Authors: Knowlson Catherine , Torgerson David J.
Published: August 2020

The RECOVERY trial is a large multi-armed, adaptive randomised controlled trial of treatments for Covid-19.  It has rapidly recruited and demonstrated that hydroxychloroquine is ineffective in reducing mortality for hospitalised patients, whilst dexamethasone significantly reduces mortality among those patients using supplemental oxygen or on a ventilator.  We estimate that the speed of recruitment and dissemination has probably decreased mortality in the UK by at least 200 hospitalised patients in the first month since the British Prime Minister announced the results.  Despite its impressive speed, the trial only recruited about 15% of eligible patients, with recruitment rates ranging between 3% to 80% at participating hospitals.  Had the trial recruited 50% of the eligible patients then our analysis suggests that more than 2,000 additional lives could have been saved.  In a pandemic, rapid recruitment with high centre recruitment is absolutely essential to reduce deaths.  Methods of improving site specific recruitment rates need investigating urgently.
How Does the Economy Shape the Financial Advisory Profession?
Authors: Law Kelvin K. F. , Zuo Luo
Published: August 2020

We examine whether economic conditions have a long-term impact on the composition of available financial advisors in the profession. We find that financial advisors who start their career in recessions are less likely to commit professional misconduct throughout their career, even compared with their colleagues working in the same firm, at the same location, and at the same point in time. We show that this relation between early economic conditions and advisor misconduct remains after controlling for differences in hiring firms, advisor characteristics, and opportunities to commit misconduct. Collectively, our evidence suggests that economic conditions shape the types of financial advisors who are ultimately available in the profession.

This paper was accepted by Brian Bushee, accounting.
Bundling for Flexibility and Variety: An Economic Model for Multiproducer Value Aggregation
Authors: Bhargava Hemant K.
Published: August 2020

Many markets feature an economic structure in which value is cocreated by multiple producers and aggregated into a common bundle by a producer-consortium or independent firm. Examples include in-home video entertainment, technology goods and services, multisourced data platforms, and patent pools. This paper develops an economic model to study demand, production choices, revenue sharing, and relative market power in such markets. Producers in these markets are not rivalrous competitors in the usual zero-sum sense, because output of each casts an externality on production decisions of others and total market demand expands with total output, albeit with diminishing returns. This property allows multiple producers to flourish in equilibrium (versus just one with the most favorable technological or cost structure), and more so when the market expands less quickly with total output. Equilibrium production quantities of competitors are strategic complements, yet competition between producers does manifest itself, for example, if one acquires better production technology (i.e., makes value units at lower cost) then the equilibrium production levels of other producers are reduced. Insights are also derived for alternative market structures, for example, producers have more output and earn higher profit when organized into a distribution consortium (e.g., Hulu or consortia of zoos or museums) versus relying on a separate retailer. Mergers between producers have similar effect. The formulation enables us to rigorously answer economic questions ranging from pricing, revenue sharing, and production levels in a static setting, to market dynamics covering both the causes and effects of changes in industry structure.

This paper was accepted by Chris Forman, information systems.
Analysis of the effect of methadone and temperature on the development rate of Calliphora vicina (Diptera: Calliphoridae): A forensically important fly
Authors: Kshvary Dawoud , Rassi Yavar , Azizi Kourosh , OSHAGHI MOHAMMAD ALI , RAFIZADEH SAYENA , ALIMOHAMMADI ALI MOHAMMAD , NAMADI MARZIEA SHAHRIARI , PARKHIDEH SEYEDEH ZAHRA
Published: August 2020

Abstract. Keshavarzi D, Rassi Y, Azizi K, Oshaghi MA, Rafizadeh S, Alimohammadi AM, Namadi MS, Parkhideh SZ. 2020. Analysis of the effect of methadone and temperature on the development rate of Calliphora vicina (Diptera: Calliphoridae): A forensically important fly. Nusantara Bioscience 12: 87-91.  The development rate/time of flies is a scientific method to estimate the minimum time elapsed after death. Several studies have shown that opioids and temperature affect maggot growth rates. However, there are few published data that investigate the effect of ante-mortem methadone use on larval length of Calliphora vicina (Robineau-Desvoidy). Therefore, the purpose of this research was to investigate the effect of methadone and temperature on the development rate/time of this species. During this study, four rabbits were administered 0.10, 0.50, 1.0, and 10 mg/kg of methadone via gavage over a period of 14 days, and a five rabbit, which did not receive methadone, was used as a control. The rabbits' tissues were separated and exposed to maggots for rearing. Minimum developmental times of C. vicina life stages at six constant temperature regimes were provided. From hours 48 to 96, larvae feeding on tissues containing 10 mg/kg methadone developed more rapidly than those feeding on tissues containing 0.1, 0.50, and 1 mg/kg and also from the control. In the present study, development rate of C. vicina was linearly related to temperature (R2 = 0.96, p =0.02) between 16 and 32°C. The results revealed that the differences observed in the rates of development were sufficient to alter postmortem interval estimates based on larval development by up to 24 h.
Preoperative scar perception study comparing ‘scarless’ in the neck endoscopic thyroidectomy with open thyroidectomy: a cross-sectional study
Authors: Qiu TY , Lau JWL , Wong O , Oh HB , Boon TW , Parameswaran R , Ngiam KY
Published: August 2020

Introduction

Open thyroidectomy is the most common approach to thyroid surgery. However, ‘scarless’ (in the neck) endoscopic thyroidectomy, consisting of endoscopic and robotic surgery, is progressively being adopted for its perceived cosmetic benefits. This study aims to determine the patient’s preferred surgical approach and to identify the factors that influence their decision.

Materials and methods

A pilot study consisting of 100 patients with a surgical thyroid disorder were prospectively recruited from a single tertiary centre. An interviewer-administered survey was conducted. Demographic, socioeconomic status, scar perception and an adapted body image scale were evaluated to identify factors that shaped the patient’s perception of the surgical approach.

Results

The mean age of participants was 54.5 ± 13.0 years; 72% were women and 87% Chinese. Of the 100 patients, 75 patients considered scarless endoscopic thyroidectomy as their preferred surgical approach while 25 patients opted for open thyroid surgery. Improvement in scar perception score between scarless endoscopic thyroidectomy and open thyroid surgery is associated with an increased willingness to choose scarless endoscopic thyroidectomy. The mean body image scale score was 6.9 ± 2.8, indicating no statistical difference between the surgical approaches. On multivariate analysis, improvement in scar perception score (odds ratio 3.38, 95% confidence interval 1.11–10.29) and having surgeon recommendation (odds ratio 6.38, 95% confidence interval 1.80–22.63) were independently associated with interest in scarless endoscopic thyroidectomy.

Conclusion

Patients interest in undergoing scarless endoscopic thyroidectomy is driven by improved scar perception and surgeon’s recommendation compared with open thyroid surgery.
Fast calculation method for parabolic-mirror-reflection holographic 3D display using wavefront segmentation
Authors: Sando Yusuke , Satoh Kazuo , Barada Daisuke , Yatagai Toyohiko
Published: August 2020

Convex-parabolic-mirror reflection enables a very wide viewing zone in a holographic three-dimensional (3D) display. In this work, segmentation is introduced to reduce the calculation time of holograms in a convex-parabolic-mirror-reflection holographic 3D display. Wavefront segmentation can practically limit the lateral spread of the wavefront to be considered, which enables the application of geometrical approximation and conventional diffraction theories such as Fresnel diffraction. Thus, diffraction calculation via the convex parabolic mirror can be derived analytically and calculated rapidly using fast Fourier transform (FFT). Our proposed FFT-based method can calculate the diffraction integral 7000 times faster than our previous method, which involved calculating directly the diffraction integral without FFT. In addition, numerical simulation and an optical experiment are presented to verify our proposal.
Terahertz detection by upconversion to the near-infrared using picosecond pulses
Authors: Pfeiffer Tobias , Kutas Mirco , Haase Björn , Molter Daniel , von Freymann Georg
Published: August 2020

The detection of terahertz photons by using silicon-based devices enabled by visible photons is one of the fundamental ideas of quantum optics. Here, we present a classical detection principle using optical upconversion of terahertz photons to the near-infrared spectral range in the picosecond pulse regime, which finally enables the detection with a conventional sCMOS camera. By superimposing terahertz and optical pump pulses in a periodically poled lithium-niobate crystal, terahertz photons at 0.87 THz are converted to optical photons with wavelengths close to the central pump wavelength of 776 nm. A tunable delay between the pulses helps overlap the pulses and enables time-of-flight measurements. Using a sCMOS camera, we achieve a dynamic range of 47.8 dB with a signal to noise ratio of 23.5 dB at a measurement time of one second, in our current setup.
Dissipative bosonic squeezing via frequency modulation and its application in optomechanics
Authors: Wang Dong-Yang , Bai Cheng-Hua , Liu Shutian , Zhang Shou , Wang Hong-Fu
Published: August 2020

The dissipative squeezing mechanism is an effective method to generate the strong squeezing, which is important in the precision metrology. Here, we propose a practical method to achieve arbitrary bosonic squeezing via introducing frequency modulation into the coupled harmonic resonator model. We analyze the effect of frequency modulation and give the analytical and numerical squeezing results, respectively. To measure the accurate dynamic squeezing in our proposal, we give a more general defination of the relative squeezing degree. Finally, the proposed method is extended to generate the strong mechanical squeezing (>3 dB) in a practical optomechanical system consisting of a graphene mechanical oscillator coupled to a superconducting microwave cavity. The result indicates that the strong mechanical squeezing can be effectively achieved even when the mechanical oscillator is not initially in its ground state. The proposed method expands the study on nonclassical state and does not need the bichromatic microwave driving technology.
Off-axis parabolas super polished under stress: the case of the Roman Space Telescope coronagraphic instrument mirrors
Authors: Roulet Melanie , Hugot Emmanuel , Atkins Carolyn , Marcos Michel , Lombardo Simona , Bonnefoi Anne , Caillat Amandine , Ferrari Marc
Published: August 2020

Direct imaging of exoplanets requires high contrast imaging techniques that demand tight tolerances on the optical surface error. The Nancy Grace Roman Space Telescope (RST) (previously named WFIRST) aims to perform direct imaging of SuperEarth-like exoplanets through its active coronographic instrument (CGI). Eight off-axis parabola (OAP) mirrors are utilised within the CGI to create a compact instrument and to ensure access to the pupil and focal planes. The surface form error and surface roughness of these relay optics directly impact the quality of the dark hole, and therfore the observable location for exoplanets. A new fabrication process for OAP manufacture via stressed mirror polishing (SMP) is presented in this paper. First, the design of the mirror substrate is investigated to create an innovative thickness distribution capable of producing the OAP geometry with a simple warping harness composed by two micrometer screws. Second, the novel design is implemented on a 60 mm diameter OAP prototype in Zerodur; a description of the fabrication process chain and the characterisation of the optical surface over all spatial frequencies are presented. Results from this first prototype demonstrated that the surface form error deviates from < 1 nm root means square (RMS) from the simulations and with a surface roughness of 2.1 Å Ra.
Cavity requirements for realizing high-efficiency, Tm/Ho-doped, coaxial fiber laser systems
Authors: Boccuzzi Krysta A. , Newburgh G. Alex , Marciante John R.
Published: August 2020

Coaxial fiber lasers, consisting of a Ho-doped core surrounded by a Tm-doped ring, are studied via experiments and numerical simulations. Previous simulations indicated that coaxial fiber lasers have the potential to reach power conversion efficiencies of up to 54%, but experiments have yielded much lower efficiencies. To understand this difference, a wavelength dimension is added to the previous model. The new simulations explain the discrepancies with the experiments via spectral gain competition and lead to a path to optimize experimental efficiencies. Specifically, an output coupler is spectrally designed to optimize the efficiency of coaxial fiber systems, and a path towards realizing the predicted 54% efficiency is presented. The results indicate that the Tm/Ho coaxial fiber laser has the potential to be a compact and efficient means of producing 2100 nm radiation.
High-frequency and tidal period observations of suspended particulate matter in coastal waters by AHI/Himawari-8
Authors: Ding Xiaosong , He Xianqiang , Bai Yan , Zhu Qiankun , Gong Fang , Li Hao , Li Jiajia
Published: August 2020

Driven by tidal forcing and terrestrial inputs, suspended particulate matter (SPM) in shallow coastal waters usually shows high-frequency dynamics. Although specific geostationary satellite ocean color sensors such as the geostationary ocean color imager (GOCI) can observe SPM hourly eight times in a day from morning to afternoon, it cannot cover the whole semi-diurnal tidal period (∼12 h), and an hourly frequency may be insufficient to witness rapid changes in SPM in highly dynamic coastal waters. In this study, taking the Yangtze River Estuary as an example, we examined the ability of the geostationary meteorological satellite sensor AHI/Himawari-8 to monitor tidal period SPM dynamics with 10-min frequency. Results showed that the normalized water-leaving radiance (Lwn) retrieved by the AHI was consistent with the in-situ data from both cruise- and tower-based measurements. Specifically, AHI-retrieved Lwn was consistent with the in-situ cruise values, with mean relative errors (MREs) of 19.58%, 16.43%, 18.74%, and 26.64% for the 460, 510, 640, and 860 nm bands, respectively, and determination coefficients (R2) larger than 0.89. Both AHI-retrieved and tower-measured Lwn also showed good agreement, with R2 values larger than 0.75 and MERs of 14.38%, 12.42%, 18.16%, and 18.89% for 460, 510, 640, and 860 nm, respectively. Moreover, AHI-retrieved Lwn values were consistent with the GOCI hourly results in both magnitude and spatial distribution patterns, indicating that the AHI can monitor ocean color in coastal waters, despite not being a dedicated ocean color sensor. Compared to the 8 h of SPM observations by the GOCI, the AHI was able to monitor SPM dynamics for up to 12 h from early morning to late afternoon covering the whole semi-diurnal tidal period. In addition, the high-frequency 10-min monitoring by the AHI revealed the minute-level dynamics of SPM in the Yangtze River Estuary (with SPM variation amplitude found to double over 1 h), which were impossible to capture based on the hourly GOCI observations.
Violet semipolar (20-2-1) InGaN microcavity light-emitting diode with a 200 nm ultra-short cavity length
Authors: Back Joonho , Wong Matthew S. , Kearns Jared , DenBaars Steven P. , Weisbuch Claude , Nakamura Shuji
Published: August 2020

Violet semipolar (20-2-1) InGaN microcavity light-emitting diodes (MC-LED) with a 200 nm ultra-short cavity length were demonstrated. The emission wavelength was 419 nm with a spectrum width of 20 nm. The external quantum efficiency (EQE) of MC-LED was constant at 0.8% for a forward current from 0.5 to 2 mA with the emitting area of 30×30 µm2. With increasing forward current, the peak wavelength and spectrum width of the emission showed almost no changes. For epitaxial growth, metal-organic chemical vapor deposition (MOCVD) was used. Substrate removal and tunnel-junction with an Ag-based electrode made possible the fabrication of the ultra-short 200 nm thick cavity MC-LED. This is more than a factor of 2 improvement compared to previous MC-LEDs of 450 nm cavity thickness sustaining 5 modes.
Propagation of radially polarized Hermite non-uniformly correlated beams in a turbulent atmosphere
Authors: Lin Shuqin , Wang Cong , Zhu Xinlei , Lin Rong , Wang Fei , Gbur Greg , Cai Yangjian , Yu Jiayi
Published: August 2020

We study the propagation properties of a recently introduced class of structured beams, radially polarized Hermite non-uniformly correlated (RPHNUC) beams, in a turbulent atmosphere using the extended Huygens-Fresnel integral and investigate how the mode order and coherence width play a role in resisting the degradation and depolarization effects of the turbulence. In contrast with conventional vector partially coherent beams (PCBs) with uniform (Schell-model) correlation structure, the interaction of the non-uniform correlation structure and non-uniform polarization gives these beams the ability to self-heal their intensity distribution and polarization over certain propagation ranges in turbulence. These properties suggest that RPHNUC beams may be useful in a number of applications, in particular optical trapping and free-space optical communications.
Two-way single-photon-level frequency conversion between 852 nm and 1560 nm for connecting cesium D2 line with the telecom C-band
Authors: Zhang Kong , He Jun , Wang Junmin
Published: August 2020

A compact setup for two-way single-photon-level frequency conversion between 852 nm and 1560 nm has been implemented with the same periodically-poled magnesium-oxide-doped lithium niobate (PPMgO:LN) bulk crystals for connecting cesium D2 line (852 nm) to telecom C-band. By single-pass mixing a strong continuous-wave pump laser at 1878 nm and the single-photon-level periodical signal pulses in a 50-mm-long PPMgO:LN bulk crystal, the conversion efficiency of ∼ 1.7% (∼ 1.9%) for 852-nm to 1560-nm down-conversion (1560-nm to 852-nm up-conversion) have been achieved. We analyzed noise photons induced by the strong pump laser beam, including the spontaneous Raman scattering (SRS) and the spontaneous parametric down-conversion (SPDC) photons, and the photons generated in the cascaded nonlinear processes. The signal-to-noise ratio (SNR) has been improved remarkably by using the narrow-band filters and changing polarization of the noise photons in the difference frequency generation (DFG) process. With further improvement of the conversion efficiency by employing PPMgO:LN waveguide, instead of bulk crystal, our study may provide the basics for cyclic photon conversion in quantum network.
Physiology-like crystalline lens modelling for children
Authors: Li Qing , Fang Fengzhou
Published: August 2020

Understanding the age-dependent properties of the crystalline lenses of children is fundamental in studying the mechanism of myopic development and progression. A more realistic lens structure has more power for predicting the optical properties of the crystalline lenses. In this manuscript, a new lens model is proposed to predict the age-dependent change in the crystalline lens for children aged 6 to 15 years old. The lens model has the capability of involving most parameters measurable on the in vivo human lens. Moreover, the discrepancy of refractive indices at the equatorial edge and anterior and posterior vertices of the external lens surface is explained systematically. The analysis shows that this discrepancy has a significant role on the optical performance of the lens. The age-dependent properties are modelled based on available experimental data. The relationship between structural and optical performance is investigated with three-dimensional ray-tracing. The contributions of each parameter to the optical power and spherical aberration are revealed. The study has highlighted the importance of building physiology-like crystalline lens structure since some parameters ignored by previous studies can have a great optical impact.
2 × 2 16-ch silicon photonics wavelength-selective switch based on waveguide gratings
Authors: Ikeda Kazuhiro , Konoike Ryotaro , Suzuki Keijiro , Kawashima Hitoshi
Published: August 2020

We demonstrate a 2 × 2 16-ch silicon photonics wavelength-selective switch consisting of contra-directional couplers and thermo-optic Mach-Zehnder switches. The contra-directional couplers are based on sidewall corrugated Bragg gratings with an unlimited free spectral range and thus enable the device to operate over a very wide wavelength range of the C- and L-band. We obtain a fiber-to-fiber insertion loss of 9.2 dB, an on-chip loss of 5.4 dB, a 3-dB bandwidth of 4.2 nm, a bar-port extinction of 15.0 dB, and a cross-port extinction of 23.0 dB, all in 16-ch average. An average trimming power for the bar states and an average switching power for the cross states are 3.8 mW (σ = 2.3 mW) and 15.6 mW (σ = 2.1 mW), respectively. The wavelength dependence of the spectral responses and the resonant effect from the apodization are discussed in detail to show how to further improve the spectral performance.
FBG-referenced interrogating system using a double-ring erbium-doped fiber laser for high power and broadband
Authors: Kang Kyumin , Jang Minsu , Kim Byung Kook , Kim Jun Sik , Lim Myo Taeg , Kim Jinseok
Published: August 2020

In this study, a double-ring erbium-doped fiber (EDF) laser with an optical switch and a fiber Bragg grating (FBG)-referenced interrogating system was developed and demonstrated. This double-ring configuration can achieve high power amplified spontaneous emission, enabling laser oscillation even within the L-band. The output range and signal-to-noise ratio (SNR) of the double-ring EDF laser were measured to be 1512–1610 nm and 55 dB. In addition, the interrogating system using FBGs for reference resulted in precision improvement of ∼25 pm over those achieved in previous studies, reaching a precision of about 7 pm. The high power, broad tuning range, and sufficiently high precision of the proposed interrogating system make it promising for use in FBG-based sensing applications.
Asymmetric surface wave excitation through metasurface-edge diffraction
Authors: Camacho Miguel , Capolino Filippo , Albani Matteo
Published: August 2020

The selective excitation of localized surface wave modes remains a challenge in the design of both leaky-wave and bound-wave devices. In this Letter, we show how the truncation of a metasurface can play an important role in breaking the spatial inversion symmetry in the excitation of surface waves supported by the structure. This is done by combining a large anisotropy in the dispersion relation and the presence of an edge that also serves as a coupling mechanism between the plane wave excitation and the induced surface waves. By resorting to the exact solution to the scattering problem based on a discrete Wiener–Hopf technique, we show that by inverting the component of the impinging wavevector parallel to the truncation, two distinct surface waves are excited.
Fragility of a soliton’s shot-to-shot coherence
Authors: Antikainen A. , Kabagöz H. B. , Ramachandran S.
Published: August 2020

We show that a soliton in a high-order spatial mode of a multi-mode fiber can completely lose its shot-to-shot coherence due to a noise seed with energy orders of magnitude below that of the soliton. The total degradation of shot-to-shot coherence is caused by a very strong recently demonstrated intermodal nonlinear effect, soliton self-mode conversion. The results indicate that the robustness of solitons against perturbations is not entirely applicable in the presence of intermodal nonlinearities, and, more generally, that certain single-mode results cannot be trivially extrapolated to multi-mode fibers.
High-speed PAM4 transmission with a GeSi electro-absorption modulator and dual-path neural-network-based equalization
Authors: Ruan Xiaoke , Yang Fan , Zhang Lei , Ming Hao , Li Yanping , Zhang Fan
Published: August 2020

Equalization based on artificial neural networks (NN) has proved to be an effective way for nonlinearity mitigation in various kinds of optical communication systems. In this Letter, we propose a novel methodology of dual-path neural network (DP-NN)-based equalization. By combining a linear equalizer with an input-pruned NN equalizer, DP-NN can effectively reduce the computation cost compared to a conventional NN equalizer. We confirm its feasibility through 4-ary pulse amplitude modulation (PAM4) transmission at a gross(net) bitrate of 160 Gb/s (133.3 Gb/s), based on a GeSi electro-absorption modulator operating at C-band. After a 2 km transmission, the bit error rate is below the 20% hard-decision forward-error-correction threshold of

1.5

×

10

−
2

with the DP-NN equalization, which outperforms the Volterra equalization and is comparable to conventional NN-based equalization.
Photo-induced bleaching and thermally stimulated recovery of BAC-P in Bi-doped phosphosilicate fibers
Authors: Zhao Qiancheng , Hao Qun , Luo Yanhua , Li Xiaochong , Cui Shiyu , Tan Fengze , Yu Changyuan , Peng Gang-Ding
Published: August 2020

The first results of the study on photobleaching and thermally induced recovery in Bi-doped phosphosilicate fiber have been presented. It was revealed that the rate of bleaching of phosphor-related Bi active center (BAC-P) becomes slower with the decrease of photon energy. The quadratic dependence of the bleaching rate of BAC-P on laser power is obtained under 532 nm laser irradiation. The effect of temperature on the bleaching dynamics of BAC-P is also investigated under 532 nm radiation, suggesting a thermally aggravated bleaching process upon heating at certain temperatures (

≥

300

∘

C

). Furthermore, the thermal recovery of bleached Bi-doped silica-based fiber (BDF) is investigated and a 13% increase of luminescence is achieved upon thermal quenching for 5 min at 400ºC. The underlying mechanism of photobleaching and thermo-stimulated recovery process of BAC-P is also discussed.
Chiral plasmonic metasurface absorbers in the mid-infrared wavelength range
Authors: Mahmud Md. Shamim , Rosenmann Daniel , Czaplewski David A. , Gao Jie , Yang Xiaodong
Published: August 2020

Chiral metamaterials in the mid-infrared wavelength range have tremendous potential for studying thermal emission manipulation and molecular vibration sensing. Here, we present one type of chiral plasmonic metasurface absorber with high circular dichroism (CD) in absorption of more than 0.56 across the mid-infrared wavelength range of 5–5.5 µm. The demonstrated chiral metasurface absorbers exhibit a maximum chiral absorption of 0.87 and a maximum CD in absorption of around 0.60. By adjusting the geometric parameters of the unit cell structure of the metasurface, the chiral absorption peak can be shifted to different wavelengths. Due to the strong chiroptical response, the thermal analysis of the designed chiral metasurface absorber further shows the large temperature difference between the left-handed and right-handed circularly polarized light. The demonstrated results can be utilized in various applications such as molecular detection, mid-infrared filter, thermal emission, and chiral imaging.
Field serological investigation for peste des petits ruminants, foot-and-mouth disease, and bluetongue diseases in illegally introduced animals in Egypt
Authors: Hosny Wafaa Abd El Wahab , Baheeg Eman Mohamed , Raheem Aly Hala Abd El , Abd El Nabi Samia Said , Hanna Nadia Maher
Published: August 2020

Aim: In this study, laboratory scoping on the viruses that cause peste des petits ruminants (PPR), bluetongue (BT), and foot-and-mouth disease (FMD) was performed to evaluate the current status of animals illegally introduced into Egypt. This study aims to help control these infectious illnesses and tries to prevent the introduction of other strains of these three viruses to Egypt, as these illnesses spread quickly if not controlled.

Materials and Methods: In the year 2018, 62 serum samples were collected and serologically tested through competitive enzyme-linked immunosorbent assays (ELISA) kits to detect antibodies against PPR, BT, and FMD, which are three important transboundary infectious illnesses.

Results: The results indicated that 60 out of 62 serum samples were positive for PPR antibodies (96.7%), 31 out of 62 were positive for FMD antibodies (50%), and 59 out of 62 serum samples were positive for BT antibodies (95%).

Conclusion: This study revealed that PPR, FMD, and BT can be introduced into Egypt through the illegal introduction of sheep and goat from neighboring countries. Laboratory diagnostic abilities should be improved for the early detection and control of these illnesses.
LOS DESAFÍOS DE LA INCORPORACIÓN DE TIC EN LA EDUCACIÓN UNIVERSITARIA
Authors: Fabro Ana Patricia
Published: August 2020

Inmersas en la “sociedad del conocimiento” las instituciones educativas transitan el desafío de incorporar las TIC en el marco de enfoques pedagógicos activos que posibiliten “aprender a aprender”, razón por la que el rumbo de la educación se transforma de un sistema clásico y conservador a un ambiente dinámico y creativo. La presencia y facilidad para el uso de medios interactivos en la educación, permiten que los estudiantes adquieran competencias para transformar la información en conocimiento. La actual tendencia educativa está encaminada hacia la elaboración de sistemas interactivos que permitan a los alumnos concentrarse en el razonamiento y en la resolución de problemas, dejando atrás modelos tradicionales de enseñanza centrados en la transmisión de conocimientos.
Evaluation of usage of E resources and INMAS Library Services Through Users Perspective
Authors: Soni Navin Kumar , Rani Savita , Kumar Avdhesh , Shrivastava Jitendra
Published: August 2020

The study has been an attempted to find out about the usage pattern of electronic & print journals, books and other services among users, delivered by the Institute of Nuclear Medicine & Allied Sciences (INMAS) TIRC Library. A questionnaire survey was conducted in INMAS to study the pattern of usage of library services. A total number of 150 questionnaires were distributed randomly among Scientists & Service Officers, Defence Research Technical Cadre (DRTC) and Research scholars of INMAS and 121 users responded back. The outcome of the study shows that users were quite aware about the services of the library, actively participated in collection development of books and journals, more comfortable and preferring in usage of electronic information resources. With the introduction of electronic journals/resources in library, the usage is increased manifold among users. Printed resources are also referred in good numbers by the users.
Commemorative issue of DESIDOC Journal of Library and Information Technology on DESIDOC Golden Jubilee
Authors: Suri Alka
Published: August 2020

DESIDOC was established on 29 July 1970. This is the golden jubilee year of DESIDOC. During the celebration, DESIDOC intends to release a commemorative issue of “DESIDOC Journal of Library and Information Technology” dedicated to DRDO includes 03 papers authored by scientists/ officers of DRDO and 5 from outside DRDO.
How Venus Got Her Furs
Authors: Driver Tom Amos
Published: August 2020

This, particular study explores how the Middle Ages gave birth to sadomasochistic erotica; how a burgeoning literary tradition influenced patterns of sexuality and media across medieval Europe. The bulk of the following analysis is centered around Chrétien de Troyes’ Knight of the Cart, and it is aimed at the following questions: Can the origins of sadomasochistic erotica be traced to the courtly romance of Chrétien de Troyes? What were the social ramifications of courtly romance literature? To what extent does Chrétien’s writing depict sadomasochistic relations? How did it affect patterns of sexual behavior in medieval Europe? How did it impact women’s agency? How did the world of sadomasochistic erotica change after the Middle Ages? And likewise, how did its effect on society evolve over time?
The Immediate Effect of Spinal Manipulation on Ball Velocity and Neuromuscular Function During an Instep Kick in Former Varsity Soccer Players: A Feasibility Study
Authors: Corso Melissa , Liang Carmen , Tran Steve , Howitt Scott , Srbely John , Mior Silvano A.
Published: August 2020

Corso, M, Liang, L, Tran, S, Howitt, S, Srbely, J, and Mior, SA. The immediate effect of spinal manipulation on ball velocity and neuromuscular function during an instep kick in former Varsity soccer players: a feasibility study. J Strength Cond Res 36(9): 2558–2565, 2022—Spinal manipulation (SM) has been shown to increase ball velocity (BV) in soccer players. Evidence suggests that SM modulates responses at spinal or cortical levels to enhance force production in asymptomatic populations. No studies have explored the underlying neuromuscular mechanisms contributing to changes in BV post-SM in soccer players. We assessed the feasibility of measuring change in BV and neuromuscular function after SM in former Varsity level soccer players with a pre-post study design. Three to 5 maximal instep kicks were performed before and after SM at the L3-5 level. Ball velocity was measured using high-speed camera. Activation of lower limb and trunk musculature was recorded with electromyography. Outcomes included ease of recruitment, scheduling and data capture, as well as expectation and perception of SM effect and adverse events (AE). Fifteen potential subjects were recruited over 1.5 months. Eleven were scheduled (24–31 years; 8 females, 3 males). Two subjects reported mild AE after maximal voluntary isometric contraction testing. A significant increase in BV (mean change: 1.75 m·s−1 [95% confidence interval: 0.5–3.0]) and a trend to increased peak-activation of knee extensors (90.7%) were observed post-SM. Findings suggest that our recruitment strategy and methodology are feasible in a larger trial with some modifications. Our preliminary findings support previous research by suggesting that increased BV may be mediated through increased activation of knee extensors during the kick. Our findings may offer additional insight into the underlying neuromuscular mechanisms contributing to immediate change in BV post-SM.
Ultraviolet–Visible Spectroscopy: A Qualitative Tool to Predict Dispersion and Interphase Characteristics in Carbon-Based Particulate Filled Poly (Lactic Acid) Composites
Authors: Rane Ajay Vasudeo , Kanny Krishnan , Biju Merlin , Sudhakaran Sudhikuttan Akkattil , Aravind Ammu , Thomas Sabu
Published: August 2020

Properties of polymer composites depend to a large extent on the characteristics of dispersion and interphase layers. In this work, poly (lactic acid) composites (PLAC) were prepared via the dissolution–dispersion method (DD) and oligomeric–dispersion method (OD). Ultraviolet–Visible spectroscopy (UV–VIS) was used to determine the dispersion and interphase characteristics within the PLAC. An increase in absorbance at a higher wavelength within the absorbance spectra was observed for PLAC prepared by DD and OD, which can be attributed to the formation of strong adlayers as well as “near to homogenous dispersion” for carbon-based particulate filled composites. An increase in absorbance was observed for PLAC prepared by OD in comparison to DD and can be attributed to modifications occurring at interphase regions. PLAC using carbon black, multiwalled carbon nanotubes in poly (lactic acid) were prepared via DD and OD and further characterized by UV–VIS. To study the “hybrid effect,” composites with 2.5 weight percent of carbon black with varied concentration of multiwalled carbon nanotubes and nanocellulose fibers were prepared via DD and OD, further characterized for UV–VIS. This manuscript portrays the role of UV–VIS to determine dispersion as well as the interphase characteristics for poly (lactic acid) filled carbon composites.