scholarly journals Improvement of Porous GaN-Based UV Photodetector with Graphene Cladding

2021 ◽  
Vol 11 (22) ◽  
pp. 10833
Author(s):  
Furqan Khairi Mohammed ◽  
Khi Poay Beh ◽  
Asmiet Ramizy ◽  
Naser M. Ahmed ◽  
Fong Kwong Yam ◽  
...  
Keyword(s):  
Leakage Current ◽  
Average Distance ◽  
Electrochemical Process ◽  
Electrochemical Exfoliation ◽  
Coverage Area ◽  
Uv Photodetector ◽  
Uv Sensitivity ◽  
Grown Graphene ◽  
Lower Magnitude

This work presents the role of graphene in improving the performance of a porous GaN-based UV photodetector. The porous GaN-based photodetector, with a mean pore diameter of 35 nm, possessed higher UV sensitivity, about 95% better compared to that of the as-received (non-porous) photodetector. In addition, it exhibits a lower magnitude of leakage current at dark ambient, about 70.9 μA, compared to that of the as-received photodetector with 13.7 mA. However, it is also highly resistive in nature due to the corresponding electrochemical process selectively dissolute doped regions. Herein, two types of graphene, derived from CVD and the electrochemical exfoliation (EC) process, were cladded onto the porous GaN region. The formation of a graphene/porous GaN interface, as evident from the decrease in average distance between defects as determined from Raman spectroscopy, infers better charge accumulation and conductance, which significantly improved UV sensing. While the leakage current shows little improvement, the UV sensitivity was greatly enhanced, by about 460% and 420% for CVD and EC cladded samples. The slight difference between types of graphene was attributed to the coverage area on porous GaN, where CVD-grown graphene tends to be continuous while EC-graphene relies on aggregation to form films.

scholarly journals A Role for Histone H2B During Repair of UV-Induced DNA Damage in Saccharomyces cerevisiae

Genetics ◽  
2002 ◽  
Vol 160 (4) ◽  
pp. 1375-1387
Author(s):  
Emmanuelle M D Martini ◽  
Scott Keeney ◽  
Mary Ann Osley
Keyword(s):  
Dna Damage ◽  
Dna Repair ◽  
Chromatin Structure ◽  
Specific Effect ◽  
Cell Killing ◽  
Cyclobutane Pyrimidine Dimers ◽  
Histone H2b ◽  
Uv Sensitivity ◽  
Pyrimidine Dimers

Abstract To investigate the role of the nucleosome during repair of DNA damage in yeast, we screened for histone H2B mutants that were sensitive to UV irradiation. We have isolated a new mutant, htb1-3, that shows preferential sensitivity to UV-C. There is no detectable difference in bulk chromatin structure or in the number of UV-induced cis-syn cyclobutane pyrimidine dimers (CPD) between HTB1 and htb1-3 strains. These results suggest a specific effect of this histone H2B mutation in UV-induced DNA repair processes rather than a global effect on chromatin structure. We analyzed the UV sensitivity of double mutants that contained the htb1-3 mutation and mutations in genes from each of the three epistasis groups of RAD genes. The htb1-3 mutation enhanced UV-induced cell killing in rad1Δ and rad52Δ mutants but not in rad6Δ or rad18Δ mutants, which are defective in postreplicational DNA repair (PRR). When combined with other mutations that affect PRR, the histone mutation increased the UV sensitivity of strains with defects in either the error-prone (rev1Δ) or error-free (rad30Δ) branches of PRR, but did not enhance the UV sensitivity of a strain with a rad5Δ mutation. When combined with a ubc13Δ mutation, which is also epistatic with rad5Δ, the htb1-3 mutation enhanced UV-induced cell killing. These results suggest that histone H2B acts in a novel RAD5-dependent branch of PRR.

scholarly journals Low-coherence photonic method of electrochemical processes monitoring

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Monika Kosowska ◽  
Paweł Jakóbczyk ◽  
Michał Rycewicz ◽  
Alex Vitkin ◽  
Małgorzata Szczerska
Keyword(s):  
Electrochemical Process ◽  
Electrochemical Measurements ◽  
Boron Doped Diamond ◽  
Silica Substrate ◽  
Low Coherence ◽  
Optical Responses ◽  
Boron Doped ◽  
Fabry Perot ◽  
Hybrid Characterization

AbstractWe present an advanced multimodality characterization platform for simultaneous optical and electrochemical measurements of ferrocyanides. Specifically, we combined a fiber-optic Fabry–Perot interferometer with a three-electrode electrochemical setup to demonstrate a proof-of-principle of this hybrid characterization approach, and obtained feasibility data in its monitoring of electrochemical reactions in a boron-doped diamond film deposited on a silica substrate. The film plays the dual role of being the working electrode in the electrochemical reaction, as well as affording the reflectivity to enable the optical interferometry measurements. Optical responses during the redox reactions of the electrochemical process are presented. This work proves that simultaneous opto-electrochemical measurements of liquids are possible.

scholarly journals Role of robotic natural orifice specimen extraction surgery in colorectal neoplasms

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hongliang Yao ◽  
Tiegang Li ◽  
Weidong Chen ◽  
Sanlin Lei ◽  
Kuijie Liu ◽  
...  
Keyword(s):  
Colorectal Neoplasms ◽  
Average Distance ◽  
Neoadjuvant Chemoradiotherapy ◽  
Operation Time ◽  
Patient Characteristics ◽  
Safe Procedure ◽  
Natural Orifice ◽  
Specimen Extraction ◽  
Natural Orifice Specimen Extraction

AbstractNatural orifice specimen extraction surgery (NOSES) is especially suitable for colorectal surgery. Until now, most of the reports published were about laparoscopic NOSES, the reports about robotic NOSES are extremely rare. This study aims to explore the safety and feasibility of robotic NOSES for colorectal neoplasms. All patients underwent robotic NOSES from March 2016 to October 2019 in our hospital were enrolled for retrospective analysis. Clinicopathological data including patient characteristics, perioperative information and pathological information were collected and analyzed. According to the distance between tumor and anus or whether neoadjuvant chemoradiotherapy (nRCT) is performed, we grouped the cases and studied its influence on robotic NOSES. Also, we compared the previous reports on laparoscopic NOSES with our study and revealed advantages of robotic NOSES in terms of safety and feasibility. A total of 180 patients were enrolled. The average distance from the lower edge of the tumor to the anus was (8.64 ± 3.64) cm and maximum circumferential diameter (CDmax) of specimen was (3.5 ± 1.6) cm. In terms of safety, the average operation time, intraoperative blood loss, and postoperative hospital stay were (187.5 ± 78.3) min, (47.4 ± 34) mL, and (11.3 ± 7.5) days, respectively. In terms of feasibility, the average number of lymph node harvested was (14.8 ± 5). Robotic NOSES shows advantages in terms of safety and feasibility compared with laparoscopic NOSES. This procedure could not only be a safe procedure but also could achieve good oncological outcomes.

scholarly journals Peran lurah, petugas kesehatan, dan kader dalam partisipasi ibu balita ke posyandu di wilayah cakupan D/S terendah dan tertinggi di Kota Jambi

2016 ◽  
Vol 3 (2) ◽  
pp. 87
Author(s):  
Kanda Sihombing ◽  
BJ. Istiti Kandarina ◽  
Sumarni Sumarni
Keyword(s):  
Health Care ◽  
Qualitative Method ◽  
Group Discussion ◽  
Health Staff ◽  
Community Resources ◽  
Coverage Area ◽  
Purposive Sampling ◽  
Depth Interview ◽  
Data Validity

<p><strong>ABSTRACT</strong></p><p><em><strong>Background</strong>: IHP (Integrated health post) is a form of UKBM (Community Resources Based-Health Effort) that is managed and administered from, by for and together with community in health development IHP administration involved many parties such as cadres, health staff and village head. Rawasari Primary</em><br /><em>Health Care had the lowest coverage level of D/S (33.2%), while Olak Kemang Primary Health Care had the highest D/S coverage (81.98%).</em></p><p><em><strong>Objectives</strong>: To study thoroughly the role of village head, health staff, and cadres in increasing the participation of underfive’s mothers to visit IHP.</em></p><p><em><strong>Methods</strong>: This was descriptive study used qualitative method by phonological approach. Informants were selected by purposive sampling. Data collection was performed by 2 methods, in-depth interview to 16 informants and focus group discussion (FGD) to 28 informants. Data validity was performed by source</em><br /><em>and method of triangulation.</em></p><p><em><strong>Results</strong>: Village head, nutrition staffs, health cadres, PKK woman and community figures from the highest D/S coverage area took a role in increasing participation of the mother of underfive, but they who were from the lowest D/S coverage did not. They contributed in different way in increasing their participation. Head villages gave the motivation and direction, nutrition staffs attended the IHP, cadres took a role by arrange arisan and ballon provision, and PKK’S woman delegated their member to attend IHP monthly (highest D/S) but they whom from the lowest D/S coverage area did not.</em></p><p><em><strong>Conclusion</strong>: Village head, nutrition staffs, health cadres, PKK woman, and community figures in highest D/S coverage area took a role in increasing participation of underfive’s mothers to visit IHP, but they who where from the lowest D/S coverage did not. The Innovation a creativity encourage the mothers to visit IHP.</em></p><p><strong>KEYWORDS</strong><em>: village head, health staff, cadre, PKK woman, community figure, woman who had underfive</em></p><p><strong>A</strong><strong>BSTRAK</strong></p><p><em><strong></strong></em><em><strong>Latar belakang</strong>: Posyandu merupakan bentuk upaya kesehatan bersumber daya masyarakat (UKBM) yang dikelola dan diselenggarakan dari, oleh, untuk dan bersama masyarakat dalam pembangunan kesehatan. Terselenggaranya posyandu melibatkan banyak pihak di antaranya kader, petugas kesehatan dan Lurah. Puskesmas Rawasari dengan tingkat cakupan D/S terendah yaitu 33,2%, dan Puskesmas Olak Kemang dengan cakupan D/S tertinggi yaitu 81,98%.</em></p><p><em><strong>Tujuan</strong>: Mengkaji secara mendalam peran lurah, petugas kesehatan, dan kader dalam meningkatkan partisipasi ibu balita ke posyandu. </em></p><p><em><strong>Metode</strong>: Penelitian deskriptif menggunakan metode kualitatif dengan pendekatan fenomenologi. Informan dipilih secara purposive sampling. Pengumpulan data dilakukan dengan 2 metode, wawancara mendalam terhadap 16 orang informan dan diskusi kelompok terfokus (DKT) terhadap 28 orang informan. Keabsahan data dengan melakukan triangulasi sumber dan metode.</em></p><p><em><strong>Hasil</strong>: Lurah, petugas gizi, kader, ibu PKK, dan tokoh masyarakat dari wilayah cakupan D/S tertinggi berperan dalam meningkatkan partisipasi ibu balita namun di wilayah D/S terendah tidak. Masing-masing berkontiribusi dengan cara yang berbeda misalnya lurah memberikan motivasi dan arahan, petugas gizi datang ke posyandu, kader membuat arisan dan membagikan balon saat posyandu, dan ibu PKK mendelegasikan salah satu anggota untuk datang ke posyandu setiap bulan (D/S tertinggi). Sementara kegiatan-kegiatan tersebut tidak dilakukan di wilayah D/S terendah.</em></p><p><em><strong>Kesimpulan</strong>: Lurah, petugas gizi, kader, ibu PKK dan tokoh masyarakat (D/S terendah) tidak berperan dan lurah, petugas gizi, kader, ibu PKK dan tokoh masyarakat (D/S tertinggi) berperan. Adanya inovasi dan kreativitas dari kader di Puskesmas Olak Kemang (D/S tertinggi) dapat mendorong ibu balita untuk</em><br /><em>hadir ke posyandu.</em></p><p><strong>KATA KUNCI</strong><em>: partisipasi ibu, posyandu, kader, petugas kesehatan, tokoh masyarakat</em></p>

Control of disinfection and halogenated disinfection byproducts by the electrochemical process

2007 ◽  
Vol 55 (12) ◽  
pp. 213-219 ◽  
Author(s):  
Y.J. Jung ◽  
B.S. Oh ◽  
J.W. Kang ◽  
M.A. Page ◽  
M.J. Phillips ◽  
...  
Keyword(s):  
Kinetic Studies ◽  
Disinfection Byproducts ◽  
Electrochemical Process ◽  
Free Chlorine ◽  
Haloacetic Acids ◽  
Oh Radicals ◽  
Inactivation Kinetic ◽  
E Coli ◽  
Electrochemical Processes

The aim of this study was to investigate some aspects of the performance of electrochemical process as an alternative disinfection strategy, while minimising DBPs, for water purification. The study of electrochemical processes has shown free chlorine to be produced, but smaller amounts of stronger oxidants, such as ozone, hydrogen peroxide and OH radicals (•OH), were also generated. The formation of mixed oxidants increased with increasing electric conductivity, but was limited at conductivities greater than 0.6 mS/cm. Using several microorganisms, such as E. coli and MS2 bacteriophage, inactivation kinetic studies were performed. With the exception of free chlorine, the role of mixed oxidants, especially OH radicals, was investigated for enhancement of the inactivation rate. Additionally, the formation and reduction of DBPs was studied by monitoring the concentration of haloacetic acids (HAAs) during the process.

Visual performance of horseshoe crabs day and night

1991 ◽  
Vol 7 (3) ◽  
pp. 179-189 ◽  
Author(s):  
Maureen K. Powers ◽  
Robert B. Barlow ◽  
Leonard Kass
Keyword(s):  
Horseshoe Crab ◽  
Average Distance ◽  
Natural Behavior ◽  
Object A ◽  
Circadian Changes ◽  
Horseshoe Crabs ◽  
Normal Environment ◽  
And Function ◽  
Daily Changes

AbstractA circadian clock modulates the structure and function of the lateral eyes of Limulus polyphemus, greatly increasing their sensitivity at night. During the mating season, male Limulus are visually attracted both day and night to females and objects that resemble females. This paper asks how well Limulus can see day and night, and whether the circadian changes in retinal sensitivity might influence the ability of these animals to find mates. We recorded the visual behavior of male and female horseshoe crabs in the vicinity of an object – a cement hemisphere (29.5 cm diameter) similar in size and shape to a female horseshoe crab – placed in a mating area near Mashnee Dike, Bourne, Massachusetts. Males oriented toward this target from an average distance of 0.94 m during the day and 0.88 m at night; and females appeared to avoid the target. We conclude that males can see potential mates at night almost as well as they can during the day. Apparently the circadian changes in the retina help compensate for the daily changes in illumination in the animal's normal environment. This study provides the first evidence for a role of visual circadian rhythms in an animal's natural behavior.

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