bluuebunny/crossref_metadata_2025 huggingface dataset:
A discrete-time mathematical model of stage-structured mosquito populations
Authors: Xing Yanyuan , Liu Jian , Guo Zhiming
Published: December 2019

This paper proposes a system of difference equations to model mosquito population. In this study, we develop and analyze the stage-structured models which consist of four distinct mosquito metamorphic stages: eggs, larvae, pupae, and adults. First, a model with constant birth rate is studied, and the inherent net reproduction number $\Re _{0}$ℜ0 of the model is derived. If $\Re _{0}<1$ℜ0<1, the extinction equilibrium is globally asymptotically stable. If $\Re _{0}>1$ℜ0>1, there exists a unique positive equilibrium which is uniformly persistent. When breeding is seasonal for a special case, it indicates that a unique globally asymptotically stable periodic solution is admitted when the net reproductive number is larger than one. When this value is less than one, the mosquito population goes to extinction. Finally, numerical simulations to demonstrate our findings and brief discussion are also provided.
An adaptive moving mesh method for a time-fractional Black–Scholes equation
Authors: Huang Jian , Cen Zhongdi , Zhao Jialiang
Published: December 2019

In this paper we study the numerical method for a time-fractional Black–Scholes equation, which is used for option pricing. The solution of the fractional-order differential equation may be singular near certain domain boundaries, which leads to numerical difficulty. In order to capture the singular phenomena, a numerical method based on an adaptive moving mesh is developed. A finite difference method is used to discretize the time-fractional Black–Scholes equation and error analysis for the discretization scheme is derived. Then, an adaptive moving mesh based on an a priori error analysis is established by equidistributing monitor function. Numerical experiments support these theoretical results.
Coordinating across correctional, community, and VA systems: applying the Collaborative Chronic Care Model to post-incarceration healthcare and reentry support for veterans with mental health and substance use disorders
Authors: Kim Bo , Bolton Rendelle E. , Hyde Justeen , Fincke B. Graeme , Drainoni Mari-Lynn , Petrakis Beth Ann , Simmons Molly M. , McInnes D. Keith
Published: December 2019

Background

Between 12,000 and 16,000 veterans leave incarceration annually. As is known to be the case for justice-involved populations in general, mental health disorders (MHDs) and substance use disorders (SUDs) are highly prevalent among incarcerated veterans, and individuals with MHDs and SUDs reentering the community are at increased risk of deteriorating health and recidivism. We sought to identify opportunities to better coordinate care/services across correctional, community, and VA systems for reentry veterans with MHDs and SUDs.

Methods

We interviewed 16 veterans post-incarceration and 22 stakeholders from reentry-involved federal/state/community organizations. We performed a grounded thematic analysis, and recognizing consistencies between the emergent themes and the evidence-based Collaborative Chronic Care Model (CCM), we mapped findings to the CCM’s elements – work role redesign (WRR), patient self-management support (PSS), provider decision support (PDS), clinical information systems (CIS), linkages to community resources (LCR), and organizational/leadership support (OLS).

Results

Emergent themes included (i) WRR – coordination challenges among organizations involved in veterans’ reentry; (ii) PSS – veterans’ fear of reentering society; (iii) PDS – uneven knowledge by reentry support providers regarding available services when deciding which services to connect a reentry veteran to and whether he/she is ready and/or willing to receive services; (iv) CIS – lapses in MHD/SUD medications between release and a first scheduled health care appointment, as well as challenges in transfer of medical records; (v) LCR – inconsistent awareness of existing services and resources available across a disparate reentry system; and (vi) OLS – reentry plans designed to address only immediate transitional needs upon release, which do not always prioritize MHD/SUD needs.

Conclusions

Applying the CCM to coordinating cross-system health care and reentry support may contribute to reductions in mental health crises and overdoses in the precarious first weeks of the reentry period.
Challenges and responses to infant and young child feeding in rural Rwanda: a qualitative study
Authors: Ahishakiye Jeanine , Bouwman Laura , Brouwer Inge D. , Matsiko Eric , Armar-Klemesu Margaret , Koelen Maria
Published: December 2019

Background

Despite different interventions to improve child nutrition conditions, chronic malnutrition is still a public health concern in Rwanda, with a high stunting prevalence of 38% among under 5-year-olds children. In Rwanda, only 18% of children aged 6–23 months are fed in accordance with the recommendations for infant and young child feeding practices. The aim of this study was to explore challenges to infant and young child feeding practices and the responses applied to overcome these challenges in Muhanga District, Southern province of Rwanda.

Methods

Sixteen (16) focus group discussions were held with mothers, fathers, grandmothers, and community health workers from 4 rural sectors of Muhanga District. The discussions were recorded, transcribed verbatim, and thematically analyzed using qualitative data analysis software, Atlas.ti.

Results

Two main themes emerged from the data. Firstly, there was a discourse on optimal infant and young child feeding (IYCF) practices that reflects the knowledge and efforts to align with early initiation of breastfeeding, exclusive breastfeeding for the first 6 months, as well as initiation of complementary foods at 6 months recommendations. Secondly, challenging situations against optimal practices and coping responses applied were presented in a discourse on struggling with everyday reality. The challenging situations that emerged as impeding appropriate IYCF practices included perceived lack of breast milk, infant cues, women’s heavy workload, partner relations and living in poverty. Family and social support from community health workers and health facility staff, financial support through casual labor, and mothers saving and lending groups, as well as kitchen gardens, were used to cope with challenges.

Conclusion

Factors influencing IYCF practices are multifaceted. Hence, intervention strategies to improve child nutrition should acknowledge the socially embedded nature of IYCF and address economic and social environmental constraints and opportunities, in addition and above knowledge only.
Towards improving drought resistance and lodging resistance in cotton
Authors: LI Fuguang
Published: December 2019

Cotton is one of the most important fiber and oil crop in the world and the fiber yield as well as quality traits are negatively affected by drought and lodging. Improving root gravitropism is a very effective way to enhance the crop resistance to drought and lodging stresses. Recent advance in origin and formation of root gravitropism may provide new insights to increase drought and lodging resistance in cotton.
Perspectives of patients, carers and mental health staff on early warning signs of relapse in psychosis: a qualitative investigation
Authors: Allan Stephanie , Bradstreet Simon , McLeod Hamish J. , Gleeson John , Farhall John , Lambrou Maria , Clark Andrea , Gumley Andrew I.
Published: December 2019

Background

Relapse prevention strategies based on monitoring of early warning signs (EWS) are advocated for the management of psychosis. However, there has been a lack of research exploring how staff, carers and patients make sense of the utility of EWS, or how these are implemented in context.

Aims

To develop a multiperspective theory of how EWS are understood and used, which is grounded in the experiences of mental health staff, carers and patients.

Method

Twenty-five focus groups were held across Glasgow and Melbourne (EMPOWER Trial, ISRCTN: 99559262). Participants comprised 88 mental health staff, 21 patients and 40 carers from UK and Australia (totaln= 149). Data were analysed using constructivist grounded theory.

Results

All participants appeared to recognise EWS and acknowledged the importance of responding to EWS to support relapse prevention. However, recognition of and acting on EWS were constructed in a context of uncertainty, which appeared linked to risk appraisals that were dependent on distinct stakeholder roles and experiences. Within current relapse management, a process of weighted decision-making (where one factor was seen as more important than others) described how stakeholders weighed up the risks and consequences of relapse alongside the risks and consequences of intervention and help-seeking.

Conclusions

Mental health staff, carers and patients speak about using EWS within a weighted decision-making process, which is acted out in the context of relationships that exist in current relapse management, rather than an objective response to specific signs and symptoms.
Computerised cognitive–behavioural therapy for depression in adolescents: 12-month outcomes of a UK randomised controlled trial pilot study
Authors: Wright Barry , Tindall Lucy , Hargate Rebecca , Allgar Victoria , Trépel Dominic , Ali Shehzad
Published: December 2019

Background

Computerised cognitive–behavioural therapy (CCBT) in the care pathway has the potential to improve access to psychological therapies and reduce waiting lists within Child and Adolescent Mental Health Services, however, more randomised controlled trials (RCTs) are needed to assess this.

Aims

This single-centre RCT pilot study compared a CCBT program (Stressbusters) with an attention control (self-help websites) for adolescent depression at referral to evaluate the clinical and cost-effectiveness of CCBT (trial registration: ISRCTN31219579).

Method

The trial ran within community and clinical settings. Adolescents (aged 12–18) presenting to their primary mental health worker service for low mood/depression support were assessed for eligibility at their initial appointment, 139 met inclusion criteria (a 33-item Mood and Feelings Questionnaire score of ≥20) and were randomised to Stressbusters (n = 70) or self-help websites (n = 69) using remote computerised single allocation. Participants completed mood, quality of life (QoL) and resource-use measures at intervention completion, and 4 and 12 months post-intervention. Changes in self-reported measures and completion rates were assessed by group.

Results

There was no significant difference between CCBT and the website group at 12 months. Both showed improvements on all measures. QoL measures in the intervention group showed earlier improvement compared with the website group. Costs were lower in the intervention group but the difference was not statistically significant. The cost-effectiveness analysis found just over a 65% chance of Stressbusters being cost-effective compared with websites. The 4-month follow-up results from the initial feasibility study are reported separately.

Conclusions

CCBT and self-help websites may both have a place in the care pathway for adolescents with depression.
Barriers and enablers to collaboration in the mental health system in Sabah, Malaysia: towards a theory of collaboration
Authors: Shoesmith Wendy , Awang Borhanuddin Awang Faisal Bin , Pereira Emmanuel Joseph , Nordin Norhayati , Giridharan Beena , Forman Dawn , Fyfe Sue
Published: December 2019

Background

The systems that help people with mental disorders in Malaysia include hospitals, primary care, traditional and religious systems, schools and colleges, employers, families and other community members.

Aims

To better understand collaboration between and within these systems and create a theoretical framework for system development.

Method

A total of 26 focus groups and 27 individual interviews were undertaken with patients, carers, psychiatric hospital staff, primary care and district hospital staff, religious and traditional healers, community leaders, non-governmental organisation workers, and school and college counsellors. Grounded theory methods were used to analyse the data and create a theory of collaboration.

Results

Three themes both defined and enabled collaboration: (a) collaborative behaviours; (b) motivation towards a common goal or value; and (c) autonomy. Three other enablers of collaboration were identified: (d) relatedness (for example trusting, understanding and caring about the other); (e) resources (competence, time, physical resources and opportunities); and (f) motivation for collaboration (weighing up the personal costs versus benefits of acting collaboratively).

Conclusions

The first three themes provided a definition of collaboration in this context: ‘two or more parties working together towards a common goal or value, while maintaining autonomy’. The main barriers to collaboration were lack of autonomy, relatedness, motivation and resources, together with the potential cost of acting collaboratively without reciprocation. Finding ways to change these structural, cultural and organisational features is likely to improve collaboration in this system and improve access to care and outcomes for patients.
Tirofiban hydrochloride sodium chloride injection combined with cardiovascular intervention in the treatment of Acute Myocardial Infarction
Authors: Liu Yongxuan , Zhang Lingling , Yang Yanyan
Published: December 2019

Objective: To investigate the therapeutic effect of tirofiban hydrochloride sodium chloride injection combined with cardiovascular intervention on acute myocardial infarction.

Methods: Eighty-four patients with acute myocardial infarction who were treated in our hospital from April 2017 to May 2018 were divided into a control group and a treatment group using random number table method; there were 42 patients in each group. Both groups were given conventional treatment and were treated with aspirin and clopidogrel before and after operation. Moreover, the control group was treated with cardiovascular interventional therapy, while the treatment group was treated with tirofiban hydrochloride on the basis of cardiovascular interventional therapy. The patients were followed up to observe and compare the treatment condition and adverse reactions of the two groups.

Results: After percutaneous coronary intervention, the normal rate of myocardial perfusion in the treatment group was 92.86%, which was higher than 69.05% in the control group (P<0.05). After PCI, there were significant differences of thrombolysis in myocardial infarction (TIMI) flow Grade- 2 and 3 between the two groups (P<0.05). The improvement of platelet activation function in the treatment group was better than that in the control group (P<0.05). The incidence of adverse cardiac events in the treatment group was significantly lower than that in the control group (P<0.05).

Conclusion: Tirofiban hydrochloride sodium chloride injection combined with cardiovascular intervention has a significant clinical effect in the treatment of acute myocardial infarction. It can effectively improve the blood perfusion and reduce the incidence of adverse cardiac events, suggesting a good effect on the prognosis of patients and high application value.

doi: https://doi.org/10.12669/pjms.36.1.1005

How to cite this:Liu Y, Zhang L, Yang Y. Tirofiban hydrochloride sodium chloride injection combined with cardiovascular intervention in the treatment of Acute Myocardial Infarction. Pak J Med Sci. 2020;36(1):---------. doi: https://doi.org/10.12669/pjms.36.1.1005

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Diagnostic and therapeutic approaches in rehabilitation correlated to a case of tetraparesis (with predominance of paraparesis) after severe CCT - bifronto - basal and bitemporal contusion.
Authors: STAVRICĂ Alexandru , NIRLU Luminița , POPESCU Laura Georgiana  , ALBEȘTEANU Ana Carmen , DAIA Cristina , ONOSE Gelu
Published: December 2019

Abstract
Introduction. Cranio-cerebral trauma (CCT) can be defined as a brain damage caused by an external factor. It may or may not penetrate the skull. Examples of CCT causing sources can be: car accidents, falls (from height or same level), blows with blunt objects, shooting, etc. The diagnosis is generally easy to establish through anamnesis with the patient or witnesses, then by tomography. Having the patient’s consent and The Teaching Emergency Hospital “Bagdasar-Arseni” Ethic committee’s approval, N.O. 17464 per 14.06.2019, this article presents the evolution of a 32-year-old male, tetraparetic with predominance of paraparesis, bradylalia and cerebrastenia (with significant improvement) and disgraphy, following a severe CCT - bifronto-basal and bitemporal contusion. Operated temporo-parieto-occipital fracture (right parietal decompression flap) - all by falling off the horse (affirmative). Joint stiffness in the knees (by Pellegrin-Shida heterotopic periosteal calcifications). Total post-traumatic optic atrophy RE and partial optic atrophy LE. Multiple bedsores. Neurogenic bladder (carrier of indwelling urinary catheter). UTI with Proteus Mirabiris (etiologically treated) was admitted in the Neurorehabilitation Clinic of the Teaching Emergency Hospital”Bagdasar Arseni” (TEHBA) for tetraparesis motor deficit, retention sphincter disorders, locomotor and severe auto-care dysfunctions, specialized recovery and nursing treatment with favorable development. Discussion: The peculiarity of this case is the good evolution of a patient with severe CCT and multiple associated complications. Last but not least, we can highlight how the CCT was produced, namely by falling off the horse. This tells a lot about the importance of the precautions and equipment needed during a sport, in our case wearing a helmet.
Key words: cerebral cranial trauma, tetraparesis, paraparesis, recovery,
EEG anticipation of random high and low arousal faces and sounds
Authors: Duma Gian Marco , Mento Giovanni , Semenzato Luca , Tressoldi Patrizio
Published: December 2019

Background: In this study, we investigated the neural correlates of the anticipatory activity of randomly presented faces and sounds of both high and low arousal level by recording EEG activity with a high spatial resolution EEG system.

Methods: We preregistered the following three hypotheses: 1) a contingent Negative Variation (CNV) difference in the amplitude voltage between auditory vs faces stimuli; 2) a greater amplitude voltage in the CNV, in high arousal stimuli vs low arousal stimuli, both in auditory and faces stimuli, in the temporal  window from 0 to 1000 ms before the stimulus presentation; 3) in the time window from 0 to 1000 ms a sensory specific activation at the brain source level in the temporal lobe and auditory cortex before the presentation of an auditory stimulus and an activation of occipital area, dedicated to the elaboration of visual stimuli, before the presentation of faces .

Results: Using a preregistered, hypothesis-driven approach, we found no statistically significant differences in the CNV due to an overly conservative correction for multiple comparisons for the control of Type I error. By contrast, using a data-driven approach based on a machine learning algorithm (Support Vector Machine), we found a significantly larger amplitude in the occipital cluster of electrodes before the presentation of faces with respect to sounds, along with a larger amplitude in the right auditory cortex before the presentation of sounds with respect to faces. Furthermore, we found greater CNV activity in the late prestimulus interval for high vs. low-arousal sounds stimuli in the left centro-posterior scalp regions.

Conclusions: These findings, although preliminary, seem to support the hypothesis that the neurophysiological anticipatory activity of random events is specifically driven by either the sensory characteristics or the arousal level of future stimuli.
In silico analysis of a major allergen from Rattus norvegicus, Rat n 1, and cross-reactivity with domestic pets
Authors: Munera Marlon , Contreras Neyder , Sánchez Andres , Sánchez Jorge , Emiliani Yuliana
Published: December 2019

Background:Lipocalins play a role in the cellular trafficking of pheromones and are involved in allergic responses to domestic pets. However, the cross-reactivity among allergens of this group has been poorly explored, and the pheromone linking capacity is not well characterized. The aim of this study was to explore cross-reactive epitopes and pheromone linking capacity among Rat n 1 and homologues in domestic pets through anin silicoapproach.

Methods:ElliPro and BepiPredin silicotools were used to predict B cell linear and cross-reactive epitopes. The pheromone linking capacity was explored by docking virtual screening with 2-ethylhexanol, 2,5-dimethylpyrazine, 2-sec-butyl-4,5-dihydrothiazole, and 2-heptanone ligands.

Results:According to the analysis, Rat n 1 shares 52% identity with Equ c 1, Can f 6, Fel d 4, and Mus m 1 allergens. The overlapping structures analysis  revealed high structural homology (root mean square deviation < 1). Four lineal and three discontinuous epitopes were predicted on Ra t n 1. A lineal epitope located between amino acids residues 24 and 36 was highly conserved on all allergens explored. A cross-reactive discontinuous epitope (T142, K143, D144, L145, S146, S147, D148, K152, L170, T171, T173, D174) was also found. Docking molecular simulations revealed the region involved in linking ligands, and we identified the properties of the binding of four pheromones and the binding potential of Rat n 1. Critical residues for interactions are reported in this study.

Conclusions:We identified some possible allergens fromRattus norvegicus, and those allergens could have cross-reactivity with allergens from some animals. The results need to be confirmed within vitrostudies and could be utilized to contribute to immunotherapy and reduce allergic diseases related to lipocalins.
Recent advances in understanding the phenotypes of osteoarthritis
Authors: Mobasheri Ali , Saarakkala Simo , Finnilä Mikko , Karsdal Morten A. , Bay-Jensen Anne-Christine , van Spil Willem Evert
Published: December 2019

Recent research in the field of osteoarthritis (OA) has focused on understanding the underlying molecular and clinical phenotypes of the disease. This narrative review article focuses on recent advances in our understanding of the phenotypes of OA and proposes that the disease represents a diversity of clinical phenotypes that are underpinned by a number of molecular mechanisms, which may be shared by several phenotypes and targeted more specifically for therapeutic purposes. The clinical phenotypes of OA supposedly have different underlying etiologies and pathogenic pathways and they progress at different rates. Large OA population cohorts consist of a majority of patients whose disease progresses slowly and a minority of individuals whose disease may progress faster. The ability to identify the people with relatively rapidly progressing OA can transform clinical trials and enhance their efficiency. The identification, characterization, and classification of molecular phenotypes of rapidly progressing OA, which represent patients who may benefit most from intervention, could potentially serve as the basis for precision medicine for this disabling condition. Imaging and biochemical markers (biomarkers) are important diagnostic and research tools that can assist with this challenge.
The NHS diabetic eye screening programme
Authors: Peate Ian
Published: December 2019

The NHS diabetic eye screening (DES) programme is one of the young person and adult NHS population screening programmes that are available in the UK.

The various NHS screening programmes identify those people who appear healthy, but could be at increased risk of a disease or condition. Screening is not the same as diagnosis and there will always be a possibility of some false positive and false negative results. This article in the series provides the reader with details about the DES programme. A brief overview of the anatomy of the eye is provided and the screening process is described.

The healthcare assistant and assistant practitioner (HCA and AP) have a key role to play in encouraging and emphasising the importance of screening, as well as helping the individual maintain a healthy lifestyle.
Do we still need to assess nurses' attitudes towards pressure ulcer prevention? A systematic review
Authors: Avsar Pinar , Patton Declan , O'Connor Tom , Moore Zena
Published: December 2019

Objective:

To critically appraise and synthesise existing research literature pertaining to nurses' attitudes towards pressure ulcer (PU) prevention.

Method:

Using systematic review methodology, published quantitative studies focusing on nurses' attitudes towards PU prevention measured by psychometric tests were included. The search was conducted in May 2019 using PubMed, CINAHL, Scopus, Cochrane and EMBASE databases, and returned 442 records, of which 21 met the inclusion criteria. Data were extracted using a pre-designed extraction tool and all included studies were quality appraised using the checklist.

Results:

Of the included studies, 20 employed a cross-sectional design and one author employed a validation study. In measuring nurses' attitudes toward PU prevention two distinct instruments were used: the ‘Moore and Price Attitude Scale’ and the ‘Attitude towards Pressure Ulcer Prevention Instrument’. The mean attitude score within the studies was 73% (standard deviation=9.2%). The lowest attitude score was 51%, while the highest score was 89%. The results obtained from the studies indicated that 86% (n=18) yielded positive attitude results.

Conclusion:

The findings suggest that, overall, nurses are positively disposed towards PU prevention. However, it is important to highlight that the nurses have difficulties translating this positive attitude into actual PU prevention strategies.
Zone Landslide Analysis Using Geophysical Method and Analysis of Soil Type for Disaster Mitigation In Waru Pamekasan
Authors: Ariyanto Sandy Vikki , Joni Idon
Published: December 2019

The results of this study are the factors of landslides there are many cracks in the ground, normal faults, shear faults and slope of the soil surface. The higher the slope of the land surface, the more potential for landslides. Results of XRF Waru 1 Si 58.3%, Waru 2 Ca 71.37%, Waru 3 Si 43.3%. The results of XRD Waru 1 and Waru 2 were 88% SiO2 compound, Waru 3 in the form of CaCo3 compound was 75.2%. SEM results with 10,000x enlargement Waru 1 is almost homogeneous in the form of slabs which identifies an uneven grain size and with a little porosity indicating the sample is partially amorphous in structure, Waru 2 shows an inhomogeneous sample with a fairly high porous dispersion and is not equally, Waru 3 shows the existence of an almost cube crystal form with high porosity so that it causes frequent landslides due to the density of a sand is still lacking so that it makes it easy for the land to be evicted because there are still many cavities in the soil.
High performance of an all-optical two-bit analog-to-digital converter based on Kerr effect nonlinear nanocavities
Authors: Hosseinzadeh Sani Mojtaba , Khosroabadi Saeed , Nasserian Mahshid
Published: December 2019

In this paper, a new configuration for an all-optical analog-to-digital converter based on nonlinear materials has been proposed. This structure is the combination of two main parts: a quantization block followed by an optical coder. The refractive index of the nonlinear composite material varies with the intensity of the optical field. Sampling and quantizing have been performed at central wavelength

λ
=

1550

n
m

by three ring resonators that are filled by nonlinear material AlGaAs with linear refractive index of

n
1

=

1.4

and Kerr index of

n

2

=

1.5

×

10

−
17

m

2

/

W

. The maximum sampling rate is 260 GS/S. The sampling accuracy of the structure is 1040 KS. The overall area of the structure is

540

µ

m

2

. The fast plane wave expansion method is used in the band structure calculations and the two-dimensional finite-difference time-domain method is used to calculate the transducer transmission spectrum, their resonant frequencies and quality coefficients, and the transducer output power at single wavelengths and constant intensities.
Reducing image variability across OCT devices with unsupervised unpaired learning for improved segmentation of retina
Authors: Romo-Bucheli David , Seeböck Philipp , Orlando José Ignacio , Gerendas Bianca S. , Waldstein Sebastian M. , Schmidt-Erfurth Ursula , Bogunović Hrvoje
Published: December 2019

Diagnosis and treatment in ophthalmology depend on modern retinal imaging by optical coherence tomography (OCT). The recent staggering results of machine learning in medical imaging have inspired the development of automated segmentation methods to identify and quantify pathological features in OCT scans. These models need to be sensitive to image features defining patterns of interest, while remaining robust to differences in imaging protocols. A dominant factor for such image differences is the type of OCT acquisition device. In this paper, we analyze the ability of recently developed unsupervised unpaired image translations based on cycle consistency losses (cycleGANs) to deal with image variability across different OCT devices (Spectralis and Cirrus). This evaluation was performed on two clinically relevant segmentation tasks in retinal OCT imaging: fluid and photoreceptor layer segmentation. Additionally, a visual Turing test designed to assess the quality of the learned translation models was carried out by a group of 18 participants with different background expertise. Results show that the learned translation models improve the generalization ability of segmentation models to other OCT-vendors/domains not seen during training. Moreover, relationships between model hyper-parameters and the realism as well as the morphological consistency of the generated images could be identified.
Fluorometric optical sensor arrays for the detection of urinary bladder cancer specific volatile organic compounds in the urine of patients with frank hematuria: a prospective case-control study
Authors: Zhu Simian , Huang Zhihong , Nabi Ghulam
Published: December 2019

This study outlines a simple fluorometric optical sensor system for the sensitive, real time measurement of volatile organic compounds (VOCs) as biomarkers of urinary bladder cancer in patients presenting with frank hematuria and confirmed to have the disease on histopathology. Arrays of 24 sensor points based on fluorescence VOC sensitive materials were made. Urine samples of 38 consecutive patients with pathologically confirmed bladder tumours and 41 age and gender matched healthy controls were recruited and analysed using this sensor array. This system correctly classified 68 out of 79 urine samples with 84.21% sensitivity and 87.80% specificity; the system also achieved 66.67% sensitivity and 75.00% specificity for classification of high-grade and low-grade bladder cancer patients. This study showed promising results in the detection of urinary bladder cancer as well as to classify high grade versus low grade bladder cancers.
In vivo imaging of cervical precancer using a low-cost and easy-to-use confocal microendoscope
Authors: Tang Yubo , Kortum Alex , Parra Sonia G. , Vohra Imran , Milbourne Andrea , Ramalingam Preetha , Toscano Paul A. , Schmeler Kathleen M. , Richards-Kortum Rebecca R.
Published: December 2019

Cervical cancer incidence and mortality rates remain high in medically underserved areas. In this study, we present a low-cost (<$5,000), portable and user-friendly confocal microendoscope, and we report on its clinical use to image precancerous lesions in the cervix. The confocal microendoscope employs digital apertures on a digital light projector and a CMOS sensor to implement line-scanning confocal imaging. Leveraging its versatile programmability, we describe an automated aperture alignment algorithm to ensure clinical ease-of-use and to facilitate technology dissemination in low-resource settings. Imaging performance is then evaluated in ex vivo and in vivo pilot studies; results demonstrate that the confocal microendoscope can enhance visualization of nuclear morphology, contributing to significantly improved recognition of clinically important features for detection of cervical precancer.
Persistent atomic frequency comb based on Zeeman sub-levels of an erbium-doped crystal waveguide
Authors: Askarani Mohsen Falamarzi , Lutz Thomas , Puigibert Marcelli Grimau , Sinclair Neil , Oblak Daniel , Tittel Wolfgang
Published: December 2019

Long-lived sub-levels of the electronic ground-state manifold of rare-earth ions in crystals can be used as atomic population reservoirs for photon echo-based quantum memories. We measure the dynamics of the Zeeman sub-levels of erbium ions that are doped into a lithium niobate waveguide, finding population lifetimes at cryogenic temperatures down to 0.7 K as long as seconds. Then, using these levels, we prepare and characterize atomic frequency combs (AFCs), which can serve as a memory for quantum light at 1532 nm wavelength. The results allow predicting a 0.1% memory efficiency, limited mainly by unwanted background absorption that we believe to be caused by excitation-induced erbium spin flips and frequency shifting due to two-level systems or non-equilibrium phonons. Hence, while it should be possible to create an AFC-based quantum memory in

E
r

3
+

:

T
i

4
+

:

L
i
N
b
O

3

, improved crystal growth together with optimized AFC preparation will be required to make it suitable for applications in quantum communication.
4-channel 200 Gb/s WDM O-band silicon photonic transceiver sub-assembly
Authors: Moralis-Pegios Miltiadis , Pitris Stelios , Alexoudi Theoni , Terzenidis Nikos , Ramon Hannes , Lambrecht Joris , Bauwelinck Johan , Yin Xin , Ban Yoojin , de Heyn Peter , van Campenhout Joris , Lamprecht Tobias , Lehnman Andreas , Pleros Nikos
Published: December 2019

We demonstrate a 200G capable WDM O-band optical transceiver comprising a 4-element array of Silicon Photonics ring modulators (RM) and Ge photodiodes (PD) co-packaged with a SiGe BiCMOS integrated driver and a SiGe transimpedance amplifier (TIA) chip. A 4×50 Gb/s data modulation experiment revealed an average extinction ratio (ER) of 3.17 dB, with the transmitter exhibiting a total energy efficiency of 2 pJ/bit. Data reception has been experimentally validated at 50 Gb/s per lane, achieving an interpolated 10E-12 bit error rate (BER) for an input optical modulation amplitude (OMA) of −9.5 dBm and a power efficiency of 2.2 pJ/bit, yielding a total power efficiency of 4.2 pJ/bit for the transceiver, including heater tuning requirements. This electro-optic subassembly provides the highest aggregate data-rate among O-band RM-based silicon photonic transceiver implementations, highlighting its potential for next generation WDM Ethernet transceivers.
Temperature-insensitive broadband optical parametric chirped pulse amplification based on a tilted noncollinear QPM design
Authors: Dai Dahua , Liang Chengchuan , Liang Zhaoxing , Wang Botian , Zhong Haizhe , Li Ying , Fan Dianyuan
Published: December 2019

Ultrafast pulsed laser of high intensity and high repetition rate is the combined requisite for advancing strong-field physics experiments and calls for the development of thermal-stable ultrafast laser systems. Noncollinear phasing matching (PM) is an effective solution of optimizing the properties of optical parametric chirped pulse amplification (OPCPA) to achieve broadband amplification or to be temperature-insensitive. But as a cost, distinct noncollinear geometries have to be respectively satisfied. In this paper, a noncollinear quasi-phase-matching (QPM) scheme of both temperature- and wavelength-insensitive is presented. With the assistance of the design freedom of grating wave vector, the independent noncollinear-angle requirements can be simultaneously realized in a tilted QPM crystal, and the temperature-insensitive broadband amplification is achieved. Full-dimensional spatial-temporal simulations for a typical 1064 nm pumped mid-IR OPCPA at 3.4 µm are presented in detail. Compared with a mono-functional temperature-insensitive or broadband QPM scheme, the presented QPM configuration shows a common characteristic that simultaneously optimizes the thermal stability and the gain spectrum. Broadband parametric amplification of a ∼40 fs (FWHM) pulsed laser is achieved with no signs of gain-narrowing. Both of the beam profiles and the amplified spectra stay constant while the temperature is elevated by ∼100°C. Finally, influence of the QPM grating errors on the gain spectrum is discussed.
Tunable strong coupling of two adjacent optical λ/2 Fabry-Pérot microresonators
Authors: Junginger Achim , Wackenhut Frank , Stuhl Alexander , Blendinger Felix , Brecht Marc , Meixner Alfred J.
Published: December 2019

Strong optical mode coupling between two adjacent λ/2 Fabry-Pérot microresonators consisting of three parallel silver mirrors is investigated experimentally and theoretically as a function of their detuning and coupling strength. Mode coupling can be precisely controlled by tuning the mirror spacing of one resonator with respect to the other by piezoelectric actuators. Mode splitting, anti-crossing and asymmetric modal damping are observed and theoretically discussed for the symmetric and antisymmetric supermodes of the coupled system. The spectral profile of the supermodes is obtained from the Fourier transform of the numerically calculated time evolution of the individual resonator modes, taking into account their resonance frequencies, damping and coupling constants, and is in excellent agreement with the experiments. Our microresonator design has potential applications for energy transfer between spatially separated quantum systems in micro optoelectronics and for the emerging field of polaritonic chemistry.
Impact of circadian tuning on the illuminance and color uniformity of a multichannel luminaire with spatially optimized LED placement
Authors: Abeysekera Sanush Khyle , Kalavally Vineetha , Ooi Melanie , Kuang Ye Chow
Published: December 2019

Potential advantages offered by multichannel luminaires with regards to spectral tuning are frequently overshadowed by its design challenges, a major one being the non-uniformity in illuminance and color distribution. In this paper, we present a formulation using genetic algorithm (GA) to optimize the Light Emitting Diode (LED) placement, yielding 40% superior uniformity in illuminance and color distributions compared to existing analytical formulations, substantially reducing the reliance on optical design for this purpose. It is specifically shown that our approach is employable for circadian tuning applications, even when heavily constrained by industry specifications on panel size and minimum LED separation.
Quasi-triply-degenerate states and zero refractive index in two-dimensional all-dielectric photonic crystals
Authors: Reddy Innem V. A. K. , Sukhotskiy Viktor , Baev Alexander , Liu Kai , Haus Joseph W. , Sakoda Kazuaki , Furlani Edward , Liu Jianjun , Wen Shuangchun , Prasad Paras N.
Published: December 2019

We introduce the concept of a quasi-triply-degenerate state (QTDS) and demonstrate its relation to an effective zero refractive index (ZRI) in a two-dimensional (2D) square lattice photonic crystal (PC) of all dielectric pillars. A QTDS is characterized by a triple band structure (TBS), wherein two of the bands manifest a linear dispersion around the Γ-point, i.e. a Dirac-like cone, while the third is a flat zero refractive index (ZRI) band with a frequency that is degenerate with one of the other bands. Significantly, we find that while triple degeneracy of the bands is not observed, the three bands approach one another so close that the observable properties of PCs adapted to the QTDS frequency perform as expected of a ZRI material. We closely examine the ZRI band at the Γ-point and show that by varying the PC material and structure parameters, the ZRI band behavior extends over a wide range of dielectric refractive indices enabling materials made with polymeric constituents. Moreover, the ZRI characteristics are robust and tolerant over a range of frequencies. Furthermore, the computational screening we employ to identify QTDS parameters enables the rational design of low-loss 2D ZRI materials for a broad range of photonic applications, including distributing a common reference phase, cloaking and focusing light.
Fractal superconducting nanowire avalanche photodetector at 1550  nm with 60% system detection efficiency and 1.05 polarization sensitivity
Authors: Meng Yun , Zou Kai , Hu Nan , Lan Xiaojian , Xu Liang , Zichi Julien , Steinhauer Stephan , Zwiller Val , Hu Xiaolong
Published: December 2019

Superconducting nanowire (nanostrip) single-photon detectors (SNSPDs) have shown unprecedented detection efficiency and timing properties, but simultaneously achieving polarization-insensitive high detection efficiency, low dark-count rate (DCR), fast speed, and low timing jitter remains a challenge. Here we report on our design, fabrication, and characterization of a cascaded superconducting avalanche photodetector composed of 40 nm wide NbTiN nanowires patterned into fractal curves. At the base temperature of 2.7 K, the device exhibits60±3%system detection efficiency at the wavelength of 1550 nm, 1.05 polarization sensitivity, 220 cps DCR, 4 ns recovery time, and 45 ps timing jitter. This Letter not only demonstrates these combined properties on a single detector that was unobtainable previously, but also shows that that current-crowding effect remarkably permits decent internal detection efficiency. These counter-intuitive results expand the understanding pertaining to the device physics of SNSPDs.
Optical injection dynamics of frequency combs
Authors: Doumbia Yaya , Malica Tushar , Wolfersberger Delphine , Panajotov Krassimir , Sciamanna Marc
Published: December 2019

We analyze the nonlinear dynamics of a semiconductor laser with optical injection from a frequency comb. When varying both the injection parameters (detuning and injection ratio) and the comb properties (number of comb lines and comb spacing), we identify and select several dynamics, including (1) injection locking with selective amplification of the comb line that shows the smallest detuning from the injected laser, (2) unlocked time-periodic dynamics that correspond to a new frequency comb with a broadened optical spectrum, thereby sharpening the pulse generated at the injected laser output, and (3) unlocked chaotic dynamics.
Phase engineering with all-dielectric metasurfaces for focused-optical-vortex (FOV) beams with high cross-polarization efficiency
Authors: Ahmed Hammad , Rahim Arbab Abdur , Maab Husnul , Ali Muhammad Mahmood , Mahmood Nasir , Naureen Sadia
Published: December 2019

Metasurfaces, the two-dimensional (2D) metamaterials, facilitate the implementation of abrupt phase discontinuities using an array of ultrathin and subwavelength features. These metasurfaces are considered as one of the propitious candidates for realization and development of miniaturized, surface-confined, and flat optical devices. This is because of their unprecedented capabilities to engineer the wavefronts of electromagnetic waves in reflection or transmission mode. The transmission-type metasurfaces are indispensable as the majority of optical devices operate in transmission mode. Along with other innovative applications, previous research has shown that Optical-Vortex (OV) generators based on transmission-type plasmonic metasurfaces overcome the limitations imposed by conventional OV generators. However, significant ohmic losses and the strong dispersion hampered the performance and their integration with state-of-the-art technologies. Therefore, a high contrast all-dielectric metasurface provides a compact and versatile platform to realize the OV generation. The design of this type of metasurfaces relies on the concept of Pancharatnam-Berry (PB) phase aiming to achieve a complete 2π phase control of a spin-inverted transmitted wave. Here, in this paper, we present an ultrathin, highly efficient, all-dielectric metasurface comprising nano-structured silicon on a quartz substrate. With the help of a parameter-sweep optimization, a nanoscale spatial resolution is achieved with a cross-polarized transmission efficiency as high as 95.6% at an operational wavelength of 1.55 µm. Significantly high cross-polarized transmission efficiency has been achieved due to the excitation of electric quadrupole resonances with a very high magnitude. The highly efficient control over the phase has enabled a riveting optical phenomenon. Specifically, the phase profiles of two distinct optical devices, a lens and Spiral-Phase-Plate (SPP), can be merged together, thus producing a highly Focused-Optical-Vortex (FOV) with a maximum focusing efficiency of 75.3%.
The judges’ decision is final: Judgement in music talent reality TV and school music education
Authors: Butler Alison
Published: December 2019

This article explores music talent reality television (RTV) and conceptualizes it as a site of music education. It also considers whether music talent RTV might magnify sociocultural traits that are less easily detected in other sites of music education. A considerable body of research has developed around RTV, notably from the fields of sociology, media studies, cultural studies and women’s studies. These scholars frequently draw on Bourdieu’s concepts of habitus and capital to analyse participant and audience engagements with the genre. Judgement is central to these discussions, particularly in the subgenre of music talent RTV, with several authors showing how taste and distinction are influenced by habitus. Reviewing the RTV literature highlights how certain musics and musicking experiences are judged, and how such judgement can devalue the musical experiences of those young people who are least likely to access school music education. This raises questions for further study about music talent RTV’s relationship with school music education, and for the study of music talent RTV as a music education setting in its own right, but it also highlights themes that warrant consideration in school music education sites, where judgements and their impacts on access and participation are often disguised or unquestioned.