scholarly journals The pre-exponential voltage-exponent as a sensitive test parameter for field emission theories

2021 ◽  
Vol 8 (3) ◽  
Author(s):  
R. G. Forbes ◽  
E. O. Popov ◽  
A. G. Kolosko ◽  
S. V. Filippov
Keyword(s):  
Electron Emission ◽  
Empirical Equation ◽  
Future Research ◽  
High Quality ◽  
Test Parameter ◽  
Measured Voltage ◽  
Current Voltage ◽  
Analytical Result ◽  
Theory And Experiment ◽  
Alternative Theories

For field electron emission (FE), an empirical equation for measured current I m as a function of measured voltage V m has the form I m = CV m k exp[– B / V m ], where B is a constant and C and k are constants or vary weakly with V m . Values for k can be extracted (i) from simulations based on some specific FE theory, and in principle (ii) from current–voltage measurements of sufficiently high quality. This paper shows that a comparison of theoretically derived and experimentally derived k- values could provide a sensitive and useful tool for comparing FE theory and experiment, and for choosing between alternative theories. Existing methods of extracting k -values from experimental or simulated current–voltage data are discussed, including a modernized ‘least residual’ method, and existing knowledge concerning k -values is summarized. Exploratory simulations are reported. Where an analytical result for k is independently known, this value is reliably extracted. More generally, extracted k -values are sensitive to details of the emission theory used, but also depend on assumed emitter shape; these two influences will need to be disentangled by future research, and a range of emitter shapes will need examination. Other procedural conclusions are reported. Some scientific issues that this new tool may eventually be able to help investigate are indicated.

The psychology of offering an apology: Understanding the barriers to apologizing and how to overcome them

2017 ◽  
Author(s):  
Karina Schumann
Keyword(s):  
Future Research ◽  
Perceived Threat ◽  
High Quality ◽  
Important Decision ◽  
Self Image

After committing an offense, a transgressor faces an important decision regarding whether and how to apologize to the person who was harmed. The actions he or she chooses to take after committing an offense can have dramatic implications for the victim, the transgressor, and their relationship. Although high quality apologies are extremely effective at promoting reconciliation, transgressors often choose to offer a perfunctory apology, withhold an apology, or respond defensively to the victim. Why might this be? In this article, I propose three major barriers to offering high quality apologies: (1) low concern for the victim or relationship, (2) perceived threat to self-image, and (3) perceived apology ineffectiveness. I review recent research examining how these barriers affect transgressors’ apology behavior, and describe insights this emerging work provides for developing methods to move transgressors towards more reparative behavior. Finally, I discuss important directions for future research.

scholarly journals Optimization of Plasmodium vivax sporozoite production from Anopheles stephensi in South West India

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Ajeet Kumar Mohanty ◽  
Charles de Souza ◽  
Deepika Harjai ◽  
Prathamesh Ghavanalkar ◽  
Mezia Fernandes ◽  
...  
Keyword(s):  
South Asia ◽  
Plasmodium Vivax ◽  
Anopheles Stephensi ◽  
Parasite Development ◽  
Future Research ◽  
High Quality ◽  
Gametocyte Density ◽  
Feeding Experiments ◽  
South West ◽  
Membrane Feeding

Abstract Background Efforts to study the biology of Plasmodium vivax liver stages, particularly the latent hypnozoites, have been hampered by the limited availability of P. vivax sporozoites. Anopheles stephensi is a major urban malaria vector in Goa and elsewhere in South Asia. Using P. vivax patient blood samples, a series of standard membrane-feeding experiments were performed with An. stephensi under the US NIH International Center of Excellence for Malaria Research (ICEMR) for Malaria Evolution in South Asia (MESA). The goal was to understand the dynamics of parasite development in mosquitoes as well as the production of P. vivax sporozoites. To obtain a robust supply of P. vivax sporozoites, mosquito-rearing and mosquito membrane-feeding techniques were optimized, which are described here. Methods Membrane-feeding experiments were conducted using both wild and laboratory-colonized An. stephensi mosquitoes and patient-derived P. vivax collected at the Goa Medical College and Hospital. Parasite development to midgut oocysts and salivary gland sporozoites was assessed on days 7 and 14 post-feeding, respectively. The optimal conditions for mosquito rearing and feeding were evaluated to produce high-quality mosquitoes and to yield a high sporozoite rate, respectively. Results Laboratory-colonized mosquitoes could be starved for a shorter time before successful blood feeding compared with wild-caught mosquitoes. Optimizing the mosquito-rearing methods significantly increased mosquito survival. For mosquito feeding, replacing patient plasma with naïve serum increased sporozoite production > two-fold. With these changes, the sporozoite infection rate was high (> 85%) and resulted in an average of ~ 22,000 sporozoites per mosquito. Some mosquitoes reached up to 73,000 sporozoites. Sporozoite production could not be predicted from gametocyte density but could be predicted by measuring oocyst infection and oocyst load. Conclusions Optimized conditions for the production of high-quality P. vivax sporozoite-infected An. stephensi were established at a field site in South West India. This report describes techniques for producing a ready resource of P. vivax sporozoites. The improved protocols can help in future research on the biology of P. vivax liver stages, including hypnozoites, in India, as well as the development of anti-relapse interventions for vivax malaria.

scholarly journals Much research, but little learned to date: A scoping review on mental health of health workers in low- and lower-middle income countries and roadmap for future research

2021 ◽  
Author(s):  
Julia Lohmann ◽  
Denny John ◽  
Aso Dzay
Keyword(s):  
Mental Health ◽  
Scoping Review ◽  
Health Workers ◽  
Tertiary Care ◽  
Psychological Wellbeing ◽  
Future Research ◽  
Measurement Tool ◽  
High Quality ◽  
Middle Income ◽  
Middle Income Countries

Abstract BackgroundSARS-CoV-2 has resulted in unprecedented research efforts on health workers’ work realities and their potential mental health impacts. To understand the latter, high-quality evidence on the baseline situation is paramount. With the aim of providing a comprehensive overview of existing evidence and to inform future research, we undertook a scoping review of the quantitative literature on mental health and psychological wellbeing of clinical skilled healthcare personnel working in all settings of care in low- and lower-middle income countries (LLMIC).MethodsWe performed a systematic search of the literature up to the end of 2019, in English or French language, in MEDLINE, EMBASE, PsychINFO, Global Health, and CAIRN. We included both studies estimating levels of mental health and studies investigating associations with other factors. We extracted data on study characteristics and methodology, and assessed the methodological quality of the included studies along nine criteria.ResultsWe found 143 relevant studies, 135 including data on mental health levels and 126 including data on associations with other factors. The studies covered 26 of the world’s 78 LLMICs, with most studies conducted in India, Nigeria, Pakistan, or Egypt, in urban secondary- and tertiary-care settings. 67% of studies assessed burnout, 25% general psychological wellbeing, and 20% other mental health outcomes. Only 19% of studies were of high quality due to shortcomings particularly in regards to sample representativeness, context-specific measurement tool validity, and reporting of methodological detail. We found much heterogeneity in investigated associated factors. Studies focused almost exclusively on potential determinants of mental health, while none linked mental health to objectively measured performance outcomes.ConclusionWe conclude that despite its impressive size, we can learn comparatively little from the current body of literature. Based on our findings, we outline areas for expansion, methodological improvement, and standardization of reporting in future research on mental health of health workers.Systematic review registrationPROSPERO no. CRD42019140036

scholarly journals Planting the Seeds: Orchestral Music Education as a Context for Fostering Growth Mindsets

2021 ◽  
Vol 11 ◽  
Author(s):  
Steven J. Holochwost ◽  
Judith Hill Bose ◽  
Elizabeth Stuk ◽  
Eleanor D. Brown ◽  
Kate E. Anderson ◽  
...  
Keyword(s):  
Music Education ◽  
Environmental Influence ◽  
Economic Hardship ◽  
Growth Mindset ◽  
Pedagogical Practices ◽  
Orchestral Music ◽  
Future Research ◽  
High Quality ◽  
Future Studies ◽  
Musical Growth

Growth mindset is an important aspect of children’s socioemotional development and is subject to change due to environmental influence. Orchestral music education may function as a fertile context in which to promote growth mindset; however, this education is not widely available to children facing economic hardship. This study examined whether participation in a program of orchestral music education was associated with higher levels of overall growth mindset and greater change in levels of musical growth mindset among children placed at risk by poverty. After at least 2 years of orchestral participation, students reported significantly higher levels of overall growth mindset than their peers; participating students also reported statistically significant increases in musical growth mindset regardless of the number of years that they were enrolled in orchestral music education. These findings have implications for future research into specific pedagogical practices that may promote growth mindset in the context of orchestral music education and more generally for future studies of the extra-musical benefits of high-quality music education.

scholarly journals What Are the Client, Organisational and Employee-Related Outcomes of High Quality Leadership in the Allied Health Professions? A scoping review.

2019 ◽  
Vol 14 (2) ◽  
pp. 19-30 ◽  
Author(s):  
Janice McKeever ◽  
Ted Brown
Keyword(s):  
Scoping Review ◽  
Allied Health ◽  
Grey Literature ◽  
Future Research ◽  
Reference List ◽  
High Quality ◽  
Allied Health Professionals ◽  
Consumer Expectation ◽  
Professional Groups ◽  
Modern Health Care

Background: Leadership is viewed as the panacea the complex problems in modern health care where chronic disease, contracting budgets and rising consumer expectation are challenging care provision. As the second largest workforce in Australia, Allied Health Professionals (AHP) are core contributors to health teams however they are largely absent from leadership positions and there is little evidence of their impact on client outcomes. Aim: A scoping review was carried out to synthesise evidence on the client, organisational and employee-related outcomes of high quality leadership in Allied Health. Method: A search of grey literature, peer and non-peer reviewed literature was undertaken using Embase, Emcare, SCOPUS and Psychinfo from 2010-2017. Data were sourced from journals, government reports, conference presentations and other grey literature. The reference list of key articles were hand searched for relevant research. Results: A total of 5880 articles were identified and after screening 35 articles were included for in depth review. Leadership contributed towards positive outcomes in all three domains and had influence across professional groups and services. Leaders are highly valued and respected by their teams. Allied Health leaders did not feature in any of the articles and AHP were the focus of only seven studies. The majority of articles were conference papers or case reviews that provided little robust data making it difficult to draw substantive conclusions on the outcome of AHP leadership. Conclusion: There was a lack of robust data specific to AHP leaders. Future research should attempt to gather evidence of the outcomes of AHP leadership through qualitative and quantitative means to substantiate the anecdotal evidence for high quality AHP leaders. 

Electron emission from a single Spindt‐type field emitter structure: Correlation of theory and experiment

1996 ◽  
Vol 68 (20) ◽  
pp. 2807-2809 ◽  
Author(s):  
K. L. Jensen ◽  
P. M. Phillips ◽  
K. Nguyen ◽  
L. Malsawma ◽  
C. Hor
Keyword(s):  
Electron Emission ◽  
Field Emitter ◽  
Structure Correlation ◽  
Theory And Experiment

scholarly journals A New Chloroplast DNA Extraction Protocol Significantly Improves the Chloroplast Genome Sequence Quality of Foxtail Millet (Setaria italica (L.) P. Beauv.)

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Dan Liu ◽  
Yanjiao Cui ◽  
Suying Li ◽  
Guihua Bai ◽  
Qiang Li ◽  
...  
Keyword(s):  
Nuclear Dna ◽  
Foxtail Millet ◽  
Leaf Tissue ◽  
Setaria Italica ◽  
Future Research ◽  
High Quality ◽  
Chloroplast Genomes ◽  
Zea May ◽  
Chloroplast Genome Sequence ◽  
Sequence Quality

Abstract The complexity of the leaf constitution of foxtail millet (Setaria italica (L.) P. Beauv.) makes it difficult to obtain high-purity cpDNA. Here, we developed a protocol to isolate high-quality cpDNA from foxtail millet and other crops. The new protocol replaces previous tissue grinding and homogenization by enzyme digestion of tiny leaf strips to separate protoplasts from leaf tissue and protects chloroplasts from damage by undue grinding and homogenization and from contamination of cell debris and nuclear DNA. Using the new protocol, we successfully isolated high-quality cpDNAs for whole-genome sequencing from four foxtail millet cultivars, and comparative analysis revealed that they were approximately 27‰ longer than their reference genome. In addition, six cpDNAs of four other species with narrow and thin leaf blades, including wheat (Triticum aestivum L.), maize (Zea may L.), rice (Oryza sativa L.) and sorghum (Sorghum bicolor (L.) Moench), were also isolated by our new protocol, and they all exhibited high sequence identities to their corresponding reference genomes. A maximum-likelihood tree based on the chloroplast genomes we sequenced here was constructed, and the result was in agreement with previous reports, confirming that these cpDNA sequences were available for well-supported phylogenetic analysis and could provide valuable resources for future research.

scholarly journals Critical appraisal and comparison of recommendations of clinical practice guidelines for treatment of schizophrenia in children and adolescents: a methodological survey protocol

BMJ Open ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. e038646
Author(s):  
Maíra Ramos Alves ◽  
Cristiane de Cássia Bergamaschi ◽  
Flávia Blaseck Sorrilha ◽  
Izabela Fulone ◽  
Silvio Barberato-Filho ◽  
...  
Keyword(s):  
Clinical Practice ◽  
Children And Adolescents ◽  
Clinical Practice Guidelines ◽  
Practice Guidelines ◽  
Future Research ◽  
High Quality ◽  
Agree Ii ◽  
Ethical Approval ◽  
Over Time

IntroductionThe number of clinical practice guidelines (CPGs) have increased substantially mainly in the paediatric area of mental health. However, little is known about the quality or how recommendations for the treatment of disorders such as schizophrenia in children and adolescents have changed over time. The aim of this study will be to assess the quality of the development of CPGs for the treatment and management of schizophrenia in children and adolescents over time using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) tool and to compare the recommendations and interventions described in these documents.Methods and analysisCPGs will be identified using a prospective protocol through a systematic search of multiple databases (Medline, Embase, Health Systems Evidence, Epistemonikos, Lilacs, etc) and guideline websites from 2004 to December 2020. The quality of the guidelines will be assessed by three reviewers, independently using the AGREE II. CPGs will be considered of high-quality if they scored ≥60% in four or more domains of the AGREE II instrument. Non-parametric tests will be used to test for the change of quality over time. We will summarise the different evidence grading systems and compare the recommendations.Ethics and disseminationEthical approval is not required since it is a literature-based study. Future results of the research can be submitted for publication in scientific journals of high impact, peer reviewed and also published in national and international conferences. The results derived from this study will contribute to the improvement of health institutions and policies, informing about existing recommendation guidelines and about deficiencies and qualities found in those. This study may also identify key areas for future research. This study may guide the search and choice for high quality CPGs by health policy makers and health professionals and subsidise future adaptations.Protocol registration numberCRD42020164899.

High Quality Non-Alloyed Pt Ohmic Contacts to P-Type GaN Using Two-Step Surface Treatment

1999 ◽  
Vol 595 ◽  
Author(s):  
Ja-Soon Jang ◽  
Seong-Ju Park ◽  
Tae-Yeon Seong
Keyword(s):  
Surface Treatment ◽  
Ohmic Contacts ◽  
Specific Contact Resistance ◽  
Transport Mechanisms ◽  
High Quality ◽  
Ammonium Sulfide ◽  
Current Voltage ◽  
Specific Contact ◽  
Thermionic Field Emission ◽  
P Type

AbstractTwo-step surface-treatment is introduced to obtain low resistance Pt contacts to ptype GaN. The first step is performed after the mesa etching process using buffered oxide etch (BOE) and ammonium sulfide [(NH4)2Sx]. This is followed by the second step using BOE. The Pt contact, which was treated sequentially using ultrasonically boiled BOE (10 min) and boiled (NH4)2Sx (10 min), produces a specific contact resistance of 3.0 (±3.8)×10-5 Ωcm2. However, the contact, that was simply BOE-treated, yields 3.1 (±1.1)×10-2 Ωcm2. This indicates that the two-step surface treatment is promising technique for obtaining high quality ohmic contacts to p-GaN. Investigation of the electronic transport mechanisms using current-voltage-temperature (I-V-T) data indicates that thermionic field emission is dominant in the surface-treated Pt contacts.

An analysis of field-induced hot-electron emission from metal-insulator microstructures on broad-area high-voltage electrodes

1986 ◽  
Vol 403 (1825) ◽  
pp. 285-311 ◽  
Keyword(s):  
Electron Emission ◽  
Voltage Characteristic ◽  
Spectral Shape ◽  
Hot Electron ◽  
Current Voltage Characteristic ◽  
Broad Area ◽  
Metal Insulator ◽  
Resolution Electron ◽  
Current Voltage ◽  
Vacuum Gap

High-resolution electron energy distribution measurements of individual microscopic sites have been used to develop a detailed theoretical model of the field-induced hot-electron emission mechanism responsible for pre-breakdown currents at vacuum-gap fields of 10-30 MV m -1 . The model, which is based on the formation of conducting channels in a metal-insulator-vacuum (m. i. v.) micro-emission régime, has provided experimentally verified quantitative relations for the current-voltage characteristic, spectral shape, and the field-dependence of the spectral full width at half maximum (f. w. h. m.) and shift.

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