Quantifying the quality of optical vortices by evaluating their intensity distributions

Author(s):  
Mateusz Szatkowski ◽  
Brandon Norton ◽  
Jan Masajada ◽  
Rosario Porras-Aguilar

Abstract Optical vortices are widely used in optics and photonics, ranging from microscopy and communications to astronomy. However, little work has been done to quantify the quality of scalar optical vortices. Since the quality of an optical vortex affects measurements and conclusions derived from their use, development of tools to evaluate the vortex quality is crucial. Moreover, the quality of a vortex strongly depends on the application. Therefore, this work aims to establish metrics for the evaluation of optical vortex quality. We propose to evaluate vortex quality using the following intensity parameters: eccentricity of the intensity distribution, cross-sectional peak-to-valley measurements, cross-sectional peak difference, and the ratio of the ring width to the vortex core diameter (doughnut-ratio). These parameters can be used as a guide for the quality of optical vortices depending on their implementation for specific optical technologies.

2019 ◽  
Vol 43 (6) ◽  
pp. 917-925 ◽  
Author(s):  
V.V. Kotlyar ◽  
A.A. Kovalev ◽  
A.P. Porfirev

Here, we theoretically demonstrate that if a Gaussian optical vortex is distorted by a random phase screen (diffuser) then the average intensity distribution in the focus of a spherical lens has a form of a ring with a nonzero value on the optical axis. The radius of the average-intensity ring depends on both the topological charge of an optical vortex and on the diffusing power of the diffuser. Therefore, the value of the topological charge cannot be unambiguously determined from the radius of the average intensity ring. However, the value of the topological charge of the optical vortex can be obtained from the number of points of phase singularity that can be determined using a Shack-Hartmann wavefront sensor. It is also shown that if we use a linear combination of two optical vortices, then the average intensity distribution has local maxima, the number of which is equal to the difference of the topological charges of the two original vortices. The number of these maxima no longer depends on the scattering force of the diffuser and can serve as an indicator for optical vortex identification. Modeling and experiments confirm the theoretical conclusions.


GeroPsych ◽  
2019 ◽  
Vol 32 (3) ◽  
pp. 125-134
Author(s):  
Mechthild Niemann-Mirmehdi ◽  
Andreas Häusler ◽  
Paul Gellert ◽  
Johanna Nordheim

Abstract. To date, few studies have focused on perceived overprotection from the perspective of people with dementia (PwD). In the present examination, the association of perceived overprotection in PwD is examined as an autonomy-restricting factor and thus negative for their mental well-being. Cross-sectional data from the prospective DYADEM study of 82 patient/partner dyads (mean age = 74.26) were used to investigate the association between overprotection, perceived stress, depression, and quality of life (QoL). The analyses show that an overprotective contact style with PwD has a significant positive association with stress and depression, and has a negative association with QoL. The results emphasize the importance of avoiding an overprotective care style and supporting patient autonomy.


2019 ◽  
Vol 9 (4) ◽  
pp. 413-420
Author(s):  
Amella Gusty ◽  
Dachriyanus Dachriyanus ◽  
Leni Merdawati

Kinerja perawat merupakan hasil yang dicapai dalam melaksanakan asuhan keperawatan di rumah sakit. Terciptanya asuhan keperawatan yang optimal sangat diperlukan dukungan dari pihak rumah sakit salah satunya adalah menciptakan kualitas kehidupan kerja baik bagi perawat. Penelitian ini bertujuan untuk mengetahui hubungan antara kualitas kehidupan kerja terhadap kinerja perawat pelaksana di RSUD Teluk Kuantan. Jenis penelitian kuantitatif dengan pendekatan cross sectional. Jumlah sampel 120 responden yang diperoleh melalui proportionate simple random sampling. Hasil penelitian menunjukkan kualitas kehidupan kerja perawat RSUD Teluk Kuantan berada pada kategori sedang, kinerja perawat berada pada kategori kurang baik. Berdasarkan analisis kedua variabel teridentifikasi bahwa tidak ada hubungan antara kualitas kehidupan kerja dengan kinerja perawat pelaksana dengan  p value 0,817. Dimensi work context merupakan komponen yang memiliki hubungan dengan kinerja perawat pelaksana dengan p value 0,008, dimensi work life  tidak berhubungan secara signifikan dengan kinerja perawat. Kesimpulan penelitian diketahui tidak ada hubungan antara kualitas kehidupan kerja dengan kinerja perawat pelaksana. Ada hubungan dimensi work context dengan kinerja perawat pelaksana. Tidak ada hubungan dimensi work life dengan kinerja perawat.   Kata kunci: kualitas kehidupan kerja, kinerja, perawat pelaksana   THE RELATIONSHIP BETWEEN THE QUALITY OF WORK LIFE AND THE PERFORMANCE OF IMPLEMENTERS NURSES   ABSTRACT Nurse performance is the result achieved in implementing nursing care in a hospital. The creation of optimal nursing care is very much needed support from the hospital, one of which is to create a good quality of work life for nurses. This study aims to determine the relationship between the quality of work life and the performance of nurses at the Kuantan District Hospital. This type of quantitative research with cross sectional approach. The number of samples of 120 respondents obtained through proportionate simple random sampling. The results showed that the quality of work life of nurses at the Kuantan District Hospital was in the medium category, the nurses' performance was in the unfavorable category. Based on the analysis of the two variables, it was identified that there was no relationship between the quality of work life with the performance of implementing nurses with a p value of 0.817. The work context dimension is a component that has a relationship with the performance of nurses implementing with p value 0.008, the dimension of work life does not significantly correlate with nurse performance. The conclusion of the research is that there is no relationship between the quality of work life and the performance of the implementing nurses. There is a relationship between the dimensions of the work context and the performance of the nurses. There is no relationship between the dimensions of work life and nurse performance.   Keywords: quality of work life, performance, implementers nurse


2020 ◽  
Vol 21 (1) ◽  
pp. 49
Author(s):  
Augusto Baumhardt Guidoti ◽  
Ângelo Pereira Cattani ◽  
Cintia Laura De Araujo ◽  
Fernanda Beatriz Costa Delacoste ◽  
Guilherme Scotta Hentschke ◽  
...  

The Glittre ADL-test (TGlittre) has been designed and validated to measure functional capacity during daily living activities in patients with chronic obstructive pulmonary disease (COPD) but is now used in several other situations. The aim of this study was to evaluate the applicability of TGlittre in a sample of overweight and obese eutrophic elderly. This was an experimental and cross-sectional study, which included 21 elderly women, allocated by BMI, in eutrophic (n = 8), overweight (n = 6) and obese (n = 7) groups. They were assessed for functional capacity (TGlittre and 6MWT), quality of life (QOL) with the questionnaire World Health Organization Quality of Life for Older People (WHOQOL-OLD) and handgrip strength (HGS). TGlittre correlated with age (p = 0.0040) and with 6MWT (p = 0.0086), but no statistical difference was found in TGlittre's performance time and the distance covered in 6MWT between groups. TGlittre did not correlate with HGS (p = 0.1493) and WHOQOL-Old (p = 0.0905). The data obtained in the present study corroborate that TGlittre is used as a functional measurement variable in the elderly population.Keywords: aged, obesity, exercise intolerance.­­­


2020 ◽  
Vol 26 (1) ◽  
pp. 31-36
Author(s):  
Md Zakaria Sarkar ◽  
AHM Ferdows Nur ◽  
Utpal Kumar Dutta ◽  
Muhammad Rafiqul Islam ◽  
Debabrota Roy ◽  
...  

Objective: The aim of this study was to evaluate hearing outcome after stapedotomy in patients with Otosclerosis. Methods: This cross sectional study was carried out from July 2017 to January 2019 in National Institute of ENT, Unit V. About 22 patients with Otosclerosis were included in this study. Diagnosis of Otosclerosis was based on the history, medical status with Otoscopy, Tuning fork tests and Audiometric tests. We compiled data on the pre and post operative air-bone gap (ABG) at 0.5, 1, 2 KHZ. The ABG was Calculated using AC and BC thresholds on the same audiogram. Post operative hearing gain was then Calculated from the ABG before the operation minus the ABG of the last follow up examination Results: In this study most of the cases were age group 14-30 years (72.7%), female (54.5%). Most common symptoms was progressive hearing loss, tinnitus (77.8%).The average preoperative hearing loss in this study was (AC) was 48.31±7.68. The average post opt. hearing (AC) at follow up was 28.95±10.30 with an average hearing gain of 15.40±8.53 dB which was significant. The average pre-operative ABG was 28.99 dB ± 8.10. The average post opt. ABG was analyzed at 1 follow up showed ABG 13.18±8.09 dB which was found to be significant. Conclusion: Stapedotomy is an effective surgical procedure for the treatment of otosclerosis which leads to improvement in patient’s quality of life. A favorable hearing outcome can be obtained by the combination of experienced hands with minimal surgical trauma and appropriate surgical technique. Bangladesh J Otorhinolaryngol; April 2020; 26(1): 31-36


1970 ◽  
Vol 2 (1) ◽  
Author(s):  
Remita Ully Hutagalung ◽  
F Sri Susilaningsih ◽  
Ai Mardiyah

Penyakit jantung koroner adalah penyakit yang dapat mengancam kehidupan seseorang. Pelaksanaan tindakan non bedah intervensi koroner perkutan pasien masih memiliki risiko terjadinya serangan berulang, stenosis dan ancaman kematian. Tujuan penelitian ini adalah mengidentifikasi kualitas hidup pasien pascatindakan intervensi koroner perkutan. Desain penelitian ini adalah potong lintang. Pengambilan sampel secara consecutive samplingdidapatkan 50 responden yaitu pasien yang sedang kontrol pascaintervensi coroner per kutan di Poliklinik Spesialis Jantung RSUP Dr. Hasan Sadikin Bandung, penelitian ini dilakukan pada 1-14 November 2013. Kualitas hidup diukur dengan instrumen WHOQOL-BREFdengan empat domain kualitas hidup yaitu domain fisik, psikologis, sosial, dan lingkungan. Analisis menggunakan statistik deskripsi. Hasil penelitian menunjukkan bahwa responden memiliki kualitas hidup baik sebesar 50%. Perawat memiliki peran dalam membantu pasien mencapai kualitas hidup yang optimal, diantaranya melalui peningkatan efikasi diri pasien melalui pendampingan dan pemberian informasi dalam usaha mencapai kualitas hidup.Kata kunci:Intervensi koroner perkutan, kualitas hidup, WHOQOL-BREF AbstractCoronary heart disease is a disease that can threaten person’s life, and can lead to the change of the quality of life. This coronary heart disease can be solved with non-surgical called percutaneous coronary intervention. This action will be normalized the quality of perfusion in the coronary arteries, which would certainly have an impact on the quality of life of patients. The research objective was to observe the patient of quality of life after treatment on intervention percutaneous coronary. The research design was cross sectional. There were 50 respondents taken by consecutive sampling. Data were collected in outpatient room in RSUP Dr. Hasan Sadikin Bandung, who have came with treatment routine schedule after percutaneous coronary intervention during November 1st–14th 2013. The questionnaire use WHOQOL-BREF format with 26 questions that consisting of 4 domains of quality of life: physical domain, psychological domain, social domain, and environment domain. Majority of patients were male (74 %), with the range of age mostly 56-66 years ( 34 % ), married ( 96 % ), college education was the highest ( 66 % ), the majority had not a primary job like as housewife , retired, student, etc. ( 26 % ). Data were collected using the questionnaire WHOQOL – BREF. The result have shown that rates of quality of life was good ( 50 % ) and health condition after percutaneous coronary intervention neither satisfied nor dissatisfied ( 44 % ). Nurses have a role in helping patients achieve optimal quality of life like giving information to patient correctlyKey words: Percutaneous coronary intervention, quality of life, WHOQOL – BREF


2018 ◽  
Vol 31 (3) ◽  
Author(s):  
Jolanta Majer ◽  
Sandra Pyda ◽  
Jerzy Robert Ladny ◽  
Antonio Rodriguez-Nunez ◽  
Lukasz Szarpak

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