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The Effect of Sintering Temperature on the Densification and Magnetic Performance of NiCuZn-Ferrites (CuO: 0-6 wt.%). MATERIALS (BASEL, SWITZERLAND) 2024; 17:2293. [PMID: 38793360 PMCID: PMC11123337 DOI: 10.3390/ma17102293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 05/08/2024] [Accepted: 05/10/2024] [Indexed: 05/26/2024]
Abstract
This article reported on the effect of Cu-content and sintering temperature on the magnetic permeability and power losses of monolithic iron-deficient NiCuZn-ferrite components with low Cu-contents aimed to be used for power applications at frequencies up to 1 MHz. In particular NiαZnb1-xCuxFe1.9O4 ferrite compositions are investigated with a constant Ni/Zn atomic ratio a/b = 0.9 and 0 < x < 0.017. As found, the addition of Cu enables the achievement of good magnetic performance at lower sintering temperatures and, therefore, lower production cost. At all Cu-contents, the initial permeability as a function of the sintering temperature passes through a maximum above which structural deterioration due to asymmetric grain growth occurs. The temperature at which this maximum permeability occurs depends on the Cu content and coincides with the achievement of the maximum density of 5.1-5.2 g cm-3 (relative density ~97%). At Cu-contents x = 0.006-0.012 and sintering temperatures 1200-1100 °C power losses (tan(δ)/μ at 1 MHz, 25 °C) οf 50 × 10-6 could be achieved and initial permeabilities (10 kHz, 0.1 mT, 25 °C) of around 400 with very good frequency and temperature stability. At CuO content higher than 4 wt.% (i.e., x > 0.012) and sintering temperatures higher than 1150 °C, pronounced microstructural disturbances due to asymmetric grain growth result in low permeabilities and high losses. It is suggested that at low CuO contents and low sintering temperatures, the densification enhancement may not proceed through Cu-rich phase segregation but through the creation of oxygen vacancies.
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Estimation of the economic impact of a bluetongue serotype 4 outbreak in Tunisia. Front Vet Sci 2024; 11:1310202. [PMID: 38487710 PMCID: PMC10937385 DOI: 10.3389/fvets.2024.1310202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 02/19/2024] [Indexed: 03/17/2024] Open
Abstract
Introduction Since 1999, Tunisia has experienced multiple occurrences of Bluetongue (BT) outbreaks, leading to numerous reported cases of infection and mortality in flocks. The re-emergence of the disease in 2020 caused substantial economic losses in cattle, attributed to the incursion of serotype BTV-4. Methods To evaluate the economic impact of the recent BT episode, we conducted a retrospective study on outbreaks that occurred in Tunisia between August and November 2020, focusing on the impact at the owner's level and its effects on both small ruminants and cattle. A total of 234 ruminant farms (sheep, cattle, and mixed) were randomly selected across Tunisian governorates and included in the study to estimate both the direct and indirect costs of these outbreaks. Results Total costs were calculated as the sum of losses and expenditures resulting from the BT outbreaks. At the animal level, total losses were estimated to range between 116.280 and 207.086 TND for one infected ewe (€33.721 and 60.055). For one lactating cow, costs varied between 2,590.724 and 3,171.107 TND (€751.310 and 919.621). In cattle, exposure to BTV led to a daily unit milk yield decrease of 12.50 to 14.66 L over an average period of 5 months. Diseased sheep experienced weight loss ranging between 4 and 10 kg during the BT outbreaks. The total mean cost of the 2020 BT outbreak in Tunisian investigated farms was estimated at 1,935 million TND (million €561.15) (range: 1,489 and 2,474 million TND; 431.81 and million €717.46). The most influential costs of the total BT outbreaks were the decrease in milk yield, mortality, and veterinary treatment. Discussion This study gives valuable insights on the economic impact of the incursion of a new serotype of BT in a naive population in Tunisia. Considering the substantial costs incurred, it is imperative that this disease receives increased attention from stakeholders, including animal owners, veterinary services, practitioners, and decision-makers.
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Unlocking Nature's Secrets: Molecular Insights into Postharvest Pathogens Impacting Moroccan Apples and Innovations in the Assessment of Storage Conditions. PLANTS (BASEL, SWITZERLAND) 2024; 13:553. [PMID: 38498518 PMCID: PMC10891559 DOI: 10.3390/plants13040553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 01/29/2024] [Accepted: 02/14/2024] [Indexed: 03/20/2024]
Abstract
Apple production holds a prominent position in Morocco's Rosaceae family. However, annual production can fluctuate due to substantial losses caused by fungal diseases affecting stored apples. Our findings emphasize that the pre-storage treatment of apples, disinfection of storage facilities, box type, and fruit sorting are pivotal factors affecting apple losses during storage. Additionally, the adopted preservation technique was significantly correlated with the percentage of damage caused by fungal infections. Blue mold accounts for nearly three-quarters of the diseases detected, followed by gray rot with a relatively significant incidence. This study has revealed several fungal diseases affecting stored apples caused by pathogens such as Penicillium expansum, Botrytis cinerea, Alternaria alternata, Trichothecium roseum, Fusarium avenaceum, Cadophora malorum, and Neofabraea vagabunda. Notably, these last two fungal species have been reported for the first time in Morocco as pathogens of stored apples. These data affirm that the high losses of apples in Morocco, attributed primarily to P. expansum and B. cinerea, pose a significant threat in terms of reduced production and diminished fruit quality. Hence, adopting controlled atmosphere storage chambers and implementing good practices before apple storage is crucial.
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Australian Cool-Season Pulse Seed-Borne Virus Research: 1. Alfalfa and Cucumber Mosaic Viruses and Less Important Viruses. Viruses 2024; 16:144. [PMID: 38257844 PMCID: PMC10819373 DOI: 10.3390/v16010144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 01/12/2024] [Accepted: 01/12/2024] [Indexed: 01/24/2024] Open
Abstract
Here, we review the research undertaken since the 1950s in Australia's grain cropping regions on seed-borne virus diseases of cool-season pulses caused by alfalfa mosaic virus (AMV) and cucumber mosaic virus (CMV). We present brief background information about the continent's pulse industry, virus epidemiology, management principles and future threats to virus disease management. We then take a historical approach towards all past investigations with these two seed-borne pulse viruses in the principal cool-season pulse crops grown: chickpea, faba bean, field pea, lentil, narrow-leafed lupin and white lupin. With each pathosystem, the main focus is on its biology, epidemiology and management, placing particular emphasis on describing field and glasshouse experimentation that enabled the development of effective phytosanitary, cultural and host resistance control strategies. Past Australian cool-season pulse investigations with AMV and CMV in the less commonly grown species (vetches, narbon bean, fenugreek, yellow and pearl lupin, grass pea and other Lathyrus species) and those with the five less important seed-borne pulse viruses also present (broad bean stain virus, broad bean true mosaic virus, broad bean wilt virus, cowpea mild mottle virus and peanut mottle virus) are also summarized. The need for future research is emphasized, and recommendations are made regarding what is required.
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Prevalence and economic losses associated with foetal wastage in abattoir. Vet Med Sci 2024; 10:e1343. [PMID: 38227705 PMCID: PMC10790323 DOI: 10.1002/vms3.1343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 11/06/2023] [Accepted: 12/10/2023] [Indexed: 01/18/2024] Open
Abstract
BACKGROUND Both male and female food animals are slaughtered for meat. Some cows, ewes and does slaughtered are found with viable foetuses resulting in foetal wastage and loss of future replacement stock. Foetal wastage accounts for about 20%-25% of the decline in livestock numbers in sub-Saharan Africa. Slaughter of pregnant cows, ewes and does results in economic losses and threatens food security with consequent decrease in available animal proteins to the fast growing human population. Protein requirement for healthy human development is inadequate in most developing countries including Uganda. The prevalence and economic losses associated with foetal wastage were assessed in an abattoir. OBJECTIVES The study was cnducted to assess the prevalence of feotal wastage at the study abattoir and estimate the associated economic losses. METHODS The researchers supported by abattoir resident meat inspectors examined all slaughtered female animals during the study period. Gravid uteri obtained from slaughtered animals after dressing of carcasses were eviscerated using a sharp knife across the long axis to recover foetuses. The crown rump lengths (CRLs) of the recovered foetuses were measured using a tape measure, weighed on a scale and categorised into first, second and third trimesters. Prevalence of pregnant animals slaughtered was determined by calculating the percentage of pregnant animals over the total number of female animals slaughtered. Economic losses were estimated based on the monetary losses at birth, weaning, maturity, and carcass loss at weaning and maturity. RESULTS The aggregate slaughters were bovine 604 (73.6%), caprine 169 (20.6%) and ovine 48 (5.9%). The overall prevalence of foetal wastage was 21.9%. The aggregate prevalence of foetal wastage by species include 160 (88.9%) cows, 8 (4.4%) heifers, 4 (2.2%) does and 8 (4.4%) ewes. Foetal wastage of cows by trimester included 62 (38.8%), 26 (16.25%) and 72 (45.0%) in first, second and third trimesters, respectively, translating into loss of US$13,055. Foetal wastage was high and the associated economic losses were substantial which undermines sustainability of the national herd. Farmers should be sensitised about the economic losses and long-term impact associated with foetal wastage and dissuaded from this practice. A policy is needed to deter farmers from selling pregnant animals for slaughter. CONCLUSIONS A total of 168 bovine, 8 caprine and 12 ovine foetuses were wasted within 60 days study period. These foetal wastages translated to US$ 13,224 monetary losses at birth, US$ 31,849 monetary loss at weaning and US$ 57,0896 monetary loss at maturity.
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Ceratocystis fimbriata Causing Postharvest Fruit Rot of Pear in Punjab, Pakistan. PLANT DISEASE 2023. [PMID: 37700477 DOI: 10.1094/pdis-07-23-1448-pdn] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 09/14/2023]
Abstract
Pear (Pyrus communis) is an important deciduous fruit cultivated on a worldwide scale including Pakistan. During August 2021, a postharvest fruit rot disease was observed on several pears at various farmers market in Okara- a district of Punjab Province, Pakistan. The incidence of the disease varied from 7 to 20% with 35% disease severity. Necrotic spots (10 to 20 mm diameter) were first observed on the infected pear fruit. The spots enlarged gradually and developed into a brown, water-soaked and rotted lesion. Eventually, the whole fruit became soft, rotted and covered with a gray-brown mycelium. The isolates were obtained from the symptomatic tissues (n = 18) incubated on carrot discs that had been surface sterilized in 100-ppm streptomycin solution. After consistent sporulation of a fungus on the carrot discs, the ascospore masses formed at the tip of perithecia were transferred to malt extract agar (MEA). Primary conidia were cylindrical and hyaline (7 to 11 × 4 to 7 μm) and secondary conidia were hyaline and barrel-shaped (7 to 12 × 5 to 8 μm). Endoconidiophores with primary conidia were (12 to 27 × 2.6 to 5.5 μm). Perithecia produced on carrot discs were dark brown to black, and the base was 157 to 278 μm in diameter. Ascomatal necks were 512 to 656 µm long, dark brown to black, lighter in color at apices, tapering from base (23 to 45 μm diameter) to apex (13 to 24 μm diameter). Ostiolar hyphae were 41 to 79 μm long. Ascospores were hyaline, hat shaped, 3 to 4 μm long, and accumulated in a sticky matrix at the tips of perithecial necks. Mycelium was initially hyaline but became dark greenish brown after 7 days. Dark brown, thick-walled aleuroconidia (13 to 19.5 × 9 to 14 μm) appeared on culture plates after 2 months. Based on morphological characteristics, the fungus was identified as Ceratocystis fimbriata (Engelbrecht, 2005; Suwandi et al. 2021). To further confirm species identification, genomic DNA of two representative isolates (UO-05 and UO-06) was obtained using an extraction kit. The internal transcribed spacer (ITS) region was amplified using ITS1/4 (White et al. 1990). A BLAST search with GenBank accession nos. OR185451 and OR185456 indicated 99 to 100% identity with several C. fimbriata including type species (MH856050.1; KC493160.1; MT560374.1). Pathogenicity tests were conducted by inoculating nine disease-free pear (cv. Concord) fruit after disinfesting in 75% ethanol. A prepared spore suspension (1.0 × 106 spores/ml) was dropped on the wounds (a depth of 1 mm diameter) on the pear surface, which were made by a sterilized needle. 10 μl of a prepared spore suspension was dropped onto nine pears. Sterile water (10 μl) was dropped on the wounded sites of nine pear fruits as negative controls and all fruits were incubated in a growth chamber at 30/26°C (day/night, 90% relative humidity). Symptoms similar to those on the naturally infected fruits began after 4 to 5 days of inoculation, while controls remained healthy. The fungal isolates recovered from inoculated pears were morphologically identical to the C. fimbriata isolates originally recovered from symptomatic fruits fulfilling Koch's postulates. The pathogen has been reported to cause postharvest fruit rot of passion fruit and cucumber (Firmino et al. 2016; Li et al. 2019). To our knowledge, this is the first report of C. fimbriata causing fruit rot of pear in Punjab Province. The detection of this disease will help pear growers to take actions to monitor and prevent disease outbreak as well as develop an effective management practice when it occurs.
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Assessment of Symptoms of Grapevine Leafroll Disease and Relationship with Yield and Quality of Pinot Noir Grape Must in a 10-Year Study Period. PLANTS (BASEL, SWITZERLAND) 2023; 12:plants12112127. [PMID: 37299106 DOI: 10.3390/plants12112127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 05/17/2023] [Accepted: 05/25/2023] [Indexed: 06/12/2023]
Abstract
Grapevine leafroll disease (GLD) is caused by one or more of the Grapevine leafroll-associated viruses (GLRaVs). GLD's symptoms are expected to be evident in indicator cultivars, regardless of the GLRaV(s) involved. In the present study, disease incidence (I) and severity (S), symptoms before veraison (Sy < V), a disease severity index (DSI) and an earliness index (EI) (2013-2022) were recorded in order to examine the factors affecting the evolution of GLD in Pinot noir graft inoculated with scions infected with GLRaV-3 that, in origin, showed a diversity of GLD symptoms. Strong correlations between I and S (r = 0.94) and between Sy < V and EI (r = 0.94) were observed; early symptoms proved good predictors of incidence and severity after veraison and of yield and sugar content of the must. The environmental conditions and time after infection did not modify the wide range of symptoms (I: 0-81.5%; S: 0.1-4) that corresponded with the variation in losses (<0-88% for yield and <0-24% for sugar content). With all other factors being constant, the significant differences between plants were mainly due to the GLRaVs present. Plants infected with some GLRaV-3 isolates always had mild symptoms or remained asymptomatic 10 years after grafting but remained a source of infection for GLRaV vectors.
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Losses along the tuberculosis sputum sample referral cascade for Mpongwe District, Zambia. Afr J Prim Health Care Fam Med 2023; 15:e1-e7. [PMID: 36861920 PMCID: PMC9982457 DOI: 10.4102/phcfm.v15i1.3710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 12/22/2022] [Accepted: 01/12/2023] [Indexed: 02/24/2023] Open
Abstract
BACKGROUND In resource limited-settings, timely tuberculosis (TB) diagnosis depends upon referral of sputum samples from non-diagnostic to diagnostic facilities for examination. The TB programme data for 2018 suggested losses in Mpongwe District's sputum referral cascade. AIM This study aimed to identify the referral cascade stage where loss of sputum specimen occurred. SETTING Primary health care facilities in Mpongwe District, Copperbelt Province, Zambia. METHODS Data were retrospectively collected from one central laboratory and six referring health facilities between January and June 2019, using a paper-based tracking sheet. Descriptive statistics were generated in SPSS version 22. RESULTS Of the 328 presumptive pulmonary TB patients found in presumptive TB registers at referring facilities, 311 (94.8%) submitted sputum samples and were referred to the diagnostic facilities. Of these, 290 (93.2%) were received at the laboratory, and 275 (94.8%) were examined. The remaining 15 (5.2%) were rejected for reasons such as 'insufficient sample'. Results for all examined samples were sent back and received at referring facilities. Referral cascade completion rate was 88.4%. Median turnaround time was six days (IQR = 1.8). CONCLUSION Losses in the sputum referral cascade for Mpongwe District mainly occurred between dispatch of sputum samples and receipt at diagnostic facility. Mpongwe District Health Office needs to establish a system to monitor and evaluate the movement of sputum samples along the referral cascade to minimize losses and ensure timely TB diagnosis.Contribution: This study has highlighted, at primary health care level for resource limited settings, the stage in the sputum sample referral cascade where losses mainly occur.
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Is loss avoidance differentially rewarding in adolescents versus adults? Differences in ventral striatum and anterior insula activation during the anticipation of potential monetary losses. Cogn Neurosci 2023; 14:36-49. [PMID: 35188088 DOI: 10.1080/17588928.2022.2038555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Avoiding loss is a crucial, adaptive guide to human behavior. While previous developmental research has primarily focused on gaining rewards, less attention has been paid to loss processing and its avoidance. In daily life, it is often unknown how likely an action will result in a loss, making the role of uncertainty in loss processing particularly important. By using functional magnetic resonance imaging, we investigated the influence of varying outcome probabilities (12%, 34%, and 67%) on brain regions implicated in loss processing (ventral striatum (VS), anterior insula (AI)) by comparing 28 adolescents (10-18 years) and 24 adults (22-32 years) during the anticipation of potential monetary loss.Overall, results revealed slower RTs in adolescents compared to adults with both groups being faster in the experimental (monetary condition) vs. control trials (verbal condition). Fastest RTs were observed for the 67% outcome probability in both age groups. An age group × outcome probability interaction effect revealed the greatest differences between the groups for the 12% vs. the 67% outcome probability. Neurally, both age groups demonstrated a higher percent signal change in the VS and AI during the anticipation of potential monetary loss versus the verbal condition. However, adults demonstrated an even greater activation of VS and AI than adolescents during the anticipation of potential monetary loss, but not during the verbal condition. This may indicate that adolescents differ from adults regarding their experience of avoiding losing monetary rewards.
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Lymantria dispar (L.) (Lepidoptera: Erebidae): Current Status of Biology, Ecology, and Management in Europe with Notes from North America. INSECTS 2022; 13:insects13090854. [PMID: 36135555 PMCID: PMC9506003 DOI: 10.3390/insects13090854] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 05/13/2023]
Abstract
The European Spongy moth, Lymantria dispar (L.) (Lepidoptera: Erebidae), is an abundant species found in oak woods in Central and Southern Europe, the Near East, and North Africa and is an important economic pest. It is a voracious eater and can completely defoliate entire trees; repeated severe defoliation can add to other stresses, such as weather extremes or human activities. Lymantria dispar is most destructive in its larval stage (caterpillars), stripping away foliage from a broad variety of trees (>500 species). Caterpillar infestation is an underestimated problem; medical literature reports that established populations of caterpillars may cause health problems to people and animals. Inflammatory reactions may occur in most individuals after exposure to setae, independent of previous exposure. Currently, chemical and mechanical methods, natural predators, and silvicultural practices are included for the control of this species. Various insecticides have been used for its control, often through aerial sprayings, which negatively affect biodiversity, frequently fail, and are inappropriate for urban/recreational areas. However, bioinsecticides based on various microorganisms (e.g., entomopathogenic viruses, bacteria, and fungi) as well as technologies such as mating disruption using sex pheromone traps have replaced insecticides for the management of L. dispar.
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Abstract
OBJECTIVES Older people describe positive and negative age-related changes, but we do not know much about what contributes to make them aware of these changes. We used content analysis to categorize participants' written comments and explored the extent to which the identified categories mapped onto theoretical conceptualizations of influences on awareness of age-related change (AARC). DESIGN Cross-sectional observational study. PARTICIPANTS The study sample comprised 609 UK individuals aged 50 years or over (mean (SD) age = 67.9 (7.6) years), enrolled in the PROTECT study. MEASUREMENTS Between January and March 2019, participants provided demographic information, completed a questionnaire assessing awareness of age-related change (AARC-10 SF), and responded to an open-ended question asking them to comment on their responses. RESULTS While some of the emerging categories were in line with the existing conceptual framework of AARC (e.g. experiencing negative changes and attitudes toward aging), others were novel (e.g. engagement in purposeful activities or in activities that distract from age-related thoughts). Analysis revealed some of the thought processes involved in selecting responses to the questionnaire items, demonstrating different ways in which people make sense of specific items. CONCLUSIONS Results support the ability of the AARC questionnaire to capture perceived age-related changes in cognitive functioning, physical and mental health, and engagement in social activities and in healthy and adaptive behaviors. However, findings also suggest ways of enriching the theoretical conceptualization of how AARC develops and offer insights into interpretation of responses to measures of AARC.
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Experiments on norm focusing and losses in dictator games. FRONTIERS IN SOCIOLOGY 2022; 7:930976. [PMID: 36091094 PMCID: PMC9458908 DOI: 10.3389/fsoc.2022.930976] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 08/08/2022] [Indexed: 06/15/2023]
Abstract
We conducted experiments on norm focusing. The tests were carried out with two versions of dictator games: in one version of the game, the dictator had to allocate a gain of €10, while in the other version, a loss of €-10 needs to be allocated. In a first treatment, we focused subjects on the average giving in similar previous dictator games. The second treatment focused subjects on the behaviour of what a self-interested actor should do. In total, N = 550 participants took part in our experiments. We found (1) a significant difference in giving behaviour between gain and loss treatments, with subjects being moderately more self-interested in the loss domain, (2) a significant effect of focusing subjects on the average behaviour of others, but (3) no effect of focusing subjects on the behaviour of self-interested actors.
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Modeling of High-Power Tonpilz Terfenol-D Transducer Using Complex Material Parameters. SENSORS 2022; 22:s22103781. [PMID: 35632187 PMCID: PMC9144425 DOI: 10.3390/s22103781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 05/05/2022] [Accepted: 05/10/2022] [Indexed: 02/01/2023]
Abstract
The loss effect in smart materials, the active part of a transducer, is of significant importance to acoustic transducer designers, as it directly affects the important characteristics of the transducer, such as the impedance spectra, frequency response, and the amount of heat generated. It is therefore beneficial to be able to incorporate energy losses in the design phase. For high-power low-frequency transducers requiring more smart materials, losses become even more appreciable. In this paper, similar to piezoelectric materials, three losses in Terfenol-D are considered by introducing complex quantities, representing the elastic loss, piezomagnetic loss, and magnetic loss. The frequency-dependent eddy current loss is also considered and incorporated into the complex permeability of giant magnetostrictive materials. These complex material parameters are then successfully applied to improve the popular plane-wave method (PWM) circuit model and finite element method (FEM) model. To verify the accuracy and effectiveness of the proposed methods, a high-power Tonpilz Terfenol-D transducer with a resonance frequency of around 1 kHz and a maximum transmitting current response (TCR) of 187 dB/1A/μPa is manufactured and tested. The good agreement between the simulation and experimental results validates the improved PWM circuit model and FEA model, which may shed light on the more predictable design of high-power giant magnetostrictive transducers in the future.
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"The Internal Police Officer Has Not Retired but Has Slowed Down": Israeli Women Reframe Their Aging Experiences in the Second Half of Life. J Appl Gerontol 2022; 41:847-854. [PMID: 35019755 PMCID: PMC8847730 DOI: 10.1177/07334648211061477] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Compared with gains, losses have received a substantial amount of research and public attention. The present study aims to shed light on the positive gains associated with older age from the perspective of older women. Five focus groups with 19 Israeli women over the age of 54 were conducted. Trailers of three different films were used to stimulate discussion about old age and aging and allow for reflections on societal norms in light of personal experiences. Focus group interviews were analyzed thematically. Respondents identified four contexts, characterized by reframing their experiences against societal norms. These included gender stereotypes, physical appearance, interpersonal relations, and employment. This study represents an opening to a different discourse around old age, which is characterized by gains and possibilities brought about by changes in reframing one’s experiences, while distancing oneself and exerting free will vis à vis social norms.
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The Role of Payoff Valence on Voting: Egalitarian for Gains and Selfish for Losses. Front Psychol 2021; 12:737225. [PMID: 34899480 PMCID: PMC8653795 DOI: 10.3389/fpsyg.2021.737225] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 10/15/2021] [Indexed: 12/04/2022] Open
Abstract
We study how payoff valence affects voting behavior on the distribution of monetary outcomes framed as gains or losses in a group when using standard plurality voting (PV) procedures and when using approval voting (AV). The latter method allows the subjects to approve of as many alternatives as they wish and has been shown to eliminate the incentives to vote strategically. For both methods, we observe that voters express higher support for egalitarian allocations (and lower support for selfish options) when sharing gains than when sharing losses. Moreover, the average number of approved alternatives per ballot is higher when distributions are framed in terms of gains than when they are framed in terms of losses. We also discuss under which circumstances the shift in voting behavior is more likely to produce changes in the electoral outcome. The results suggest that framing manipulations (payoff valence) can significantly impact voting behavior.
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Resource Threat versus Resource Loss and Emotional Well-Being of Ethnic Minorities during the COVID-19 Pandemic. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph182312590. [PMID: 34886315 PMCID: PMC8657424 DOI: 10.3390/ijerph182312590] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 11/26/2021] [Accepted: 11/27/2021] [Indexed: 11/29/2022]
Abstract
This paper used Hobfoll’s conservation of resources theory as a theoretical framework to investigate which kinds of resource loss predicted the emotional well-being (EWB) of ethnic minorities and majority populations during a period of crisis. Data were collected from a national representative survey conducted by the Israel Central Bureau of Statistics during the COVID-19 pandemic. The sample included 1157 respondents, including 174 Israeli Palestinian citizens (ethnic minority) and 983 Israeli Jews (majority population). Measures of EWB, actual losses and threats of losses of economic, social, and health resources were examined. The results showed that the losses of economic, social, and health resources reduced the EWB of individuals. Negative effects of the actual losses of resources on EWB were greater than those of the perceived threats of loss. The largest effect was for economic resources. There were differences in effects between the ethnic minorities and the majority populations. The study revealed that for the ethnic minorities, who are less powerful and more disadvantaged than ethnic majorities, the depletion of already deficient resources during time of crisis is more important for predicting their EWB than for the majority populations.
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Characterization of Giant Magnetostrictive Materials Using Three Complex Material Parameters by Particle Swarm Optimization. MICROMACHINES 2021; 12:mi12111416. [PMID: 34832827 PMCID: PMC8621269 DOI: 10.3390/mi12111416] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/11/2021] [Accepted: 11/16/2021] [Indexed: 11/16/2022]
Abstract
Complex material parameters that can represent the losses of giant magnetostrictive materials (GMMs) are the key parameters for high-power transducer design and performance analysis. Since the GMMs work under pre-stress conditions and their performance is highly sensitive to pre-stress, the complex parameters of a GMM are preferably characterized in a specific pre-stress condition. In this study, an optimized characterization method for GMMs is proposed using three complex material parameters. Firstly, a lumped parameter model is improved for a longitudinal transducer by incorporating three material losses. Then, the structural damping and contact damping are experimentally measured and applied to confine the parametric variance ranges. Using the improved lumped parameter model, the real parts of the three key material parameters are characterized by fitting the experimental impedance data while the imaginary parts are separately extracted by the phase data. The global sensitivity analysis that accounts for the interaction effects of the multiple parameter variances shows that the proposed method outperforms the classical method as the sensitivities of all the six key parameters to both impedance and phase fitness functions are all high, which implies that the extracted material complex parameters are credible. In addition, the stability and credibility of the proposed parameter characterization is further corroborated by the results of ten random characterizations.
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Does Goal Orientation Modulate Satisfaction with Cognitive Performance in Different Age Groups? J Gerontol B Psychol Sci Soc Sci 2021; 77:1063-1068. [PMID: 34655290 DOI: 10.1093/geronb/gbab195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES The current experiment tested the causal effect of goal orientation on subjective satisfaction with performance on a cognitive task. METHODS A sample of N = 231 young, middle-aged, and older adults (21 - 79 years) completed a dot-memory task in one of three goal-orientation conditions aiming for improvement, maintenance, or avoidance of decline in performance. RESULTS Bayesian analyses showed that in all age groups goal orientation influenced actual performance, but did not affect perceived performance or performance satisfaction. Performance satisfaction was positively correlated with perceived performance, but not with actual performance. DISCUSSION The findings suggest that whether goal orientation benefits older adults' subjective well-being might depend on (a) the goal content (previous research targeted personal goals) or (b) whether it enhances their perception of the status quo (and thus reduces the discrepancy between actual and desired states). This study contributes to a better understanding of the role of goal orientation in subjective well-being across adulthood.
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Virus Diseases of Cereal and Oilseed Crops in Australia: Current Position and Future Challenges. Viruses 2021; 13:2051. [PMID: 34696481 PMCID: PMC8539440 DOI: 10.3390/v13102051] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/02/2021] [Accepted: 10/03/2021] [Indexed: 12/22/2022] Open
Abstract
This review summarizes research on virus diseases of cereals and oilseeds in Australia since the 1950s. All viruses known to infect the diverse range of cereal and oilseed crops grown in the continent's temperate, Mediterranean, subtropical and tropical cropping regions are included. Viruses that occur commonly and have potential to cause the greatest seed yield and quality losses are described in detail, focusing on their biology, epidemiology and management. These are: barley yellow dwarf virus, cereal yellow dwarf virus and wheat streak mosaic virus in wheat, barley, oats, triticale and rye; Johnsongrass mosaic virus in sorghum, maize, sweet corn and pearl millet; turnip yellows virus and turnip mosaic virus in canola and Indian mustard; tobacco streak virus in sunflower; and cotton bunchy top virus in cotton. The currently less important viruses covered number nine infecting nine cereal crops and 14 infecting eight oilseed crops (none recorded for rice or linseed). Brief background information on the scope of the Australian cereal and oilseed industries, virus epidemiology and management and yield loss quantification is provided. Major future threats to managing virus diseases effectively include damaging viruses and virus vector species spreading from elsewhere, the increasing spectrum of insecticide resistance in insect and mite vectors, resistance-breaking virus strains, changes in epidemiology, virus and vectors impacts arising from climate instability and extreme weather events, and insufficient industry awareness of virus diseases. The pressing need for more resources to focus on addressing these threats is emphasized and recommendations over future research priorities provided.
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Anisotropy Characterization of Metallic Lens Structures. MICROMACHINES 2021; 12:mi12091114. [PMID: 34577759 PMCID: PMC8465524 DOI: 10.3390/mi12091114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 09/13/2021] [Accepted: 09/13/2021] [Indexed: 11/19/2022]
Abstract
This paper presents a full electromagnetic (EM) characterization of metallic lenses. The method is based on the utilization of free-space transmission and reflection coefficients to accurately obtain lenses’ tensorial EM parameters. The applied method reveals a clear anisotropic behavior with a full tensorial directional permittivity and permeability and noticeably dispersive permeability and wave impedance. This method yields accurate values for the effective refractive index, wave impedance, permittivity, and permeability, unlike those obtained by simple methods such as the eigenmode method. These correct cell parameters affect their lens performance, as manifested in a clear level of anisotropy, impedance matching, and losses. The effect of anisotropy caused by oblique incidence on the performance and operation of lens designs is illustrated in a lens design case.
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Are Impulsive Decisions Always Irrational? An Experimental Investigation of Impulsive Decisions in the Domains of Gains and Losses. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18168518. [PMID: 34444268 PMCID: PMC8392628 DOI: 10.3390/ijerph18168518] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 08/08/2021] [Accepted: 08/09/2021] [Indexed: 11/16/2022]
Abstract
Intertemporal choices are very prevalent in daily life, ranging from simple, mundane decisions to highly consequential decisions. In this context, thinking about the future and making sound decisions are crucial to promoting mental and physical health, as well as a financially sustainable lifestyle. In the present study, we set out to investigate some of the possible underlying mechanisms, such as cognitive factors and emotional states, that promote future-oriented decisions. In a cross-sectional experimental study, we used a gain and a loss version of an intertemporal monetary choices task. Our main behavioural result indicated that people are substantially more impulsive over smaller and sooner monetary losses compared to equivalent gains. In addition, for both decisional domains, significant individual difference predictors emerged, indicating that intertemporal choices are sensitive to the affective and cognitive parameters. By focusing on the cognitive and emotional individual factors that influence impulsive decisions, our study could constitute a building block for successful future intervention programs targeted at mental and physical health issues, including gambling behaviour.
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Recovery of Polyphenolic Fraction from Arabica Coffee Pulp and Its Antifungal Applications. PLANTS 2021; 10:plants10071422. [PMID: 34371625 PMCID: PMC8309451 DOI: 10.3390/plants10071422] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/09/2021] [Accepted: 07/09/2021] [Indexed: 12/16/2022]
Abstract
Coffee pulp is one of the most underutilised by-products from coffee processing. For coffee growers, disposing of this agro-industrial biomass has become one of the most difficult challenges. This study utilised this potential biomass as raw material for polyphenolic antifungal agents. First, the proportion of biomass was obtained from the Arabica green bean processing. The yield of by-products was recorded, and the high-potency biomass was serially extracted with organic solvents for the polyphenol fraction. Quantification of the polyphenols was performed by High Performance Liquid Chromatography (HPLC), then further confirmed by mass spectrometry modes of the liquid chromatography–quadrupole time-of-flight (QTOF). Then, the fraction was used to test antifungal activities against Alternaria brassicicola, Pestalotiopsis sp. and Paramyrothecium breviseta. The results illustrated that caffeic acid and epigallocatechin gallate represented in the polyphenol fraction actively inhibited these fungi with an inhibitory concentration (IC50) of 0.09, 0.31 and 0.14, respectively. This study is also the first report on the alternative use of natural biocontrol agent of P. breviseta, the pathogen causing leaf spot in the Arabica coffee.
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Taming the Duplication-Loss-Coalescence Model with Integer Linear Programming. J Comput Biol 2021; 28:758-773. [PMID: 34125600 DOI: 10.1089/cmb.2021.0011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The duplication-loss-coalescence (DLC) parsimony model is invaluable for analyzing the complex scenarios of concurrent duplication loss and deep coalescence events in the evolution of gene families. However, inferring such scenarios for already moderately sized families is prohibitive owing to the computational complexity involved. To overcome this stringent limitation, we make the first step by describing a flexible integer linear programming (ILP) formulation for inferring DLC evolutionary scenarios. Then, to make the DLC model more scalable, we introduce four sensibly constrained versions of the model and describe modified versions of our ILP formulation reflecting these constraints. Our simulation studies showcase that our constrained ILP formulations compute evolutionary scenarios that are substantially larger than scenarios computable under our original ILP formulation and the original dynamic programming algorithm by Wu et al. Furthermore, scenarios computed under our constrained DLC models are remarkably accurate compared with corresponding scenarios under the original DLC model, which we also confirm in an empirical study with thousands of gene families.
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LoRaWAN for Smart Campus: Deployment and Long-Term Operation Analysis. SENSORS 2020; 20:s20236721. [PMID: 33255405 PMCID: PMC7727831 DOI: 10.3390/s20236721] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 11/16/2020] [Accepted: 11/20/2020] [Indexed: 11/16/2022]
Abstract
The recent years have gradually increased the value of wireless connectivity, making it the de facto commodity for both human users and the machines. In this paper, we summarize our experiences of deploying and managing for over two years the extensive indoor sensor network composed of more than three hundred devices connected over LoRaWAN low power wide area network (LPWAN) technology. We start by detailing the background and methodology of our deployment and then present the results of analyzing the network's operation over a period of two years, focusing specifically on identifying the reasons after the packet losses. Our results reveal that despite the common assumptions, in a real-life network, the packets are lost not only during the on-air transmission but also within the backbone. Among the other interesting findings are the observed nonuniform distribution of the packet transmissions by the nodes in the networks, the seasonal effects on the packet delivery, and the observed effects of the interferences on network performance. The empirical results presented in the paper provide valuable insight into the performance of a real-life extensive LoRaWAN network deployed in an indoor environment and thus may be of interest both to the practitioners and academics.
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Sign effect in adolescents: Within-subject comparison of delay discounting of hypothetical monetary gains and losses. J Exp Anal Behav 2020; 114:326-336. [PMID: 33015861 DOI: 10.1002/jeab.629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 08/31/2020] [Accepted: 09/03/2020] [Indexed: 11/12/2022]
Abstract
The purpose of this article is to contribute to the research on the sign effect, steeper discounting of gains compared to losses, by offering results from an experiment using a "double-delay" procedure on adolescents. Twenty-four 14-year-old schoolchildren completed a computer-based test consisting of choices of Smaller-Sooner (SS) and Larger-Later (LL) hypothetical monetary gains and losses. Within-subject comparison and analysis of the aggregated data were conducted. Current results were also examined in light of prior research with adult participants, and variations in behavioral patterns were identified. Although the sign effect appears to be more profound in adolescents compared to adults, the effect of immediacy persists regardless of the sign of the outcome, and zero discounting of losses is often the case, suggesting that the sign effect is driven largely by qualitative differences.
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Research into Two Photonic-Integrated Waveguides Based on SiGe Material. MATERIALS 2020; 13:ma13081877. [PMID: 32316298 PMCID: PMC7215922 DOI: 10.3390/ma13081877] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 04/12/2020] [Accepted: 04/14/2020] [Indexed: 11/16/2022]
Abstract
SiGe (Silicon Germanium) is a common semiconductor material with many excellent properties, and many photonic-integrated devices are designed and fabricated with SiGe material. In this paper, two photonic-integrated SiGe waveguides are researched, namely the SiGe-SOI (Silicon Germanium-Silicon-On-Insulator) waveguide and the SiGe-OI (Silicon Germanium-On-Insulator) waveguide. In order to verify which structure has the better waveguide performance, two waveguide structures are built, and the effective refractive indexes and the loss characteristics of the two waveguides are analyzed and compared. By simulation, the SiGe-OI optical waveguide has better losses characteristics at a wavelength of 1.55 μm. Finally, SiGe-OI and SiGe-SOI waveguides are fabricated and tested to verify the correctness of theoretical analysis, and the experimental results show that the transmission losses of the SiGe-OI waveguide are respectively decreased by 36.6% and 28.3% at 400 nm and 600 nm waveguide width in comparison with the SiGe-SOI waveguide. The results also show that the SiGe-OI waveguide has better loss characteristics than those of the SiGe-SOI waveguide at the low Ge content.
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A Modified Iterative Automatic Method for Characterization at Shear Resonance: Case Study of Ba 0.85Ca 0.15Ti 0.90Zr 0.10O 3 Eco-Piezoceramics. MATERIALS (BASEL, SWITZERLAND) 2020; 13:E1666. [PMID: 32260151 PMCID: PMC7178390 DOI: 10.3390/ma13071666] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 03/30/2020] [Accepted: 03/31/2020] [Indexed: 06/11/2023]
Abstract
Coupling between electrically excited electromechanical resonances of piezoelectric ceramics is undesirable for the purpose of their characterization, since the material models correspond to monomodal resonances. However, coupling takes place quite often and it is unavoidable at the shear resonance of standard in-plane poled and thickness-excited rectangular plates. The piezoelectric coefficient e15, the elastic compliance s55E and the dielectric permittivity component ε11S for a piezoelectric ceramic can be determined, including all losses, using the automatic iterative method of analysis of the complex impedance curves for the shear mode of an appropriated resonator. This is the non-standard, thickness-poled and longitudinally excited, shear plate. In this paper, the automatic iterative method is modified. The purpose is to be able to deal with the analysis of the impedance curves of the non-standard plate as the periodic phenomena of coupling and decoupling of the main shear resonance and other resonances takes place. This happens when the thickness of the plate is reduced, and its aspect ratio (width of the excitation (w)/thickness for poling (t)) is increased. In this process, the frequency of the shear resonance also increases and meets those of other plate modes periodically. We aim to obtain the best approach for the shear properties of near coupling and to reveal both their validity and the limitations of the thus-obtained information. Finally, we use a plate of a Ba0.85Ca0.15Ti0.90Zr0.10O3 eco-piezoceramic as a case study.
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Magnetic Properties of Manganese-Zinc Soft Ferrite Ceramic for High Frequency Applications. MATERIALS 2019; 12:ma12193173. [PMID: 31569765 PMCID: PMC6804056 DOI: 10.3390/ma12193173] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 09/12/2019] [Accepted: 09/24/2019] [Indexed: 11/28/2022]
Abstract
A soft magnetic MnZn-type ferrite is considered for high frequency applications. First, the morphological, structural, and chemical composition of the material are presented and discussed. Subsequently, by using a vibrating sample magnetometer (VSM), the hysteresis loops are recorded. The open magnetic circuit measurements are corrected by employing demagnetization factors, and by taking into consideration the local magnetic susceptibility. Finally, the hysteresis losses are estimated by the Steinmetz approach, and the results are compared with available commercial information provided by selected MnZn ferrite manufacturers. Such materials are representative in planar inductor and transformer cores due to their typically low losses at high frequency, i.e., up to several MHz, in low-to-medium power applications and providing high efficiency of up to 97%–99%.
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Micro-CT to Document the Coffee Bean Weevil, Araecerus fasciculatus (Coleoptera: Anthribidae), Inside Field-Collected Coffee Berries ( Coffea canephora). INSECTS 2018; 9:insects9030100. [PMID: 30110902 PMCID: PMC6164194 DOI: 10.3390/insects9030100] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 07/16/2018] [Accepted: 08/10/2018] [Indexed: 11/17/2022]
Abstract
The coffee bean weevil, Araecerus fasciculatus (De Geer) (Coleoptera: Anthribidae), is a cosmopolitan insect with >100 hosts, and has been reported as a pest of stored coffee. During a study involving the coffee berry borer, we observed coffee bean weevils emerging from field-collected coffee berries and used micro-computerized tomography (micro-CT) scans to observe the insect inside the berry. Two eggs had eclosed inside the berry, resulting in observations of a newly eclosed adult beetle and a 5th instar larva, each feeding on one of the two seeds. This is the first time since 1775, when the insect was first described, that the insect has been observed inside a coffee berry.
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Weather-Related Hazards and Population Change: A Study of Hurricanes and Tropical Storms in the United States, 1980-2012. THE ANNALS OF THE AMERICAN ACADEMY OF POLITICAL AND SOCIAL SCIENCE 2017; 669:146-167. [PMID: 29326480 PMCID: PMC5760176 DOI: 10.1177/0002716216682942] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Environmental determinists predict that people move away from places experiencing frequent weather hazards, yet some of these areas have rapidly growing populations. This analysis examines the relationship between weather events and population change in all U.S. counties that experienced hurricanes and tropical storms between 1980 and 2012. Our database allows for more generalizable conclusions by accounting for heterogeneity in current and past hurricane events and losses and past population trends. We find that hurricanes and tropical storms affect future population growth only in counties with growing, high-density populations, which are only 2 percent of all counties. In those counties, current year hurricane events and related losses suppress future population growth, although cumulative hurricane-related losses actually elevate population growth. Low-density counties and counties with stable or declining populations experience no effect of these weather events. Our analysis provides a methodologically informed explanation for contradictory findings in prior studies.
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Neural Mechanisms of the Transformation from Objective Value to Subjective Utility: Converting from Count to Worth. Front Neurosci 2016; 10:507. [PMID: 27881949 PMCID: PMC5101215 DOI: 10.3389/fnins.2016.00507] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 10/24/2016] [Indexed: 11/24/2022] Open
Abstract
When deciding, we aim to choose the “best” possible outcome. This is not just selection of the option that is the most numerous or physically largest, as options are translated from objective value (count) to subjective value (worth or utility). We localized the neural instantiation of the value-to-utility transformation to the dorsal anterior midcingulate cortex (daMCC), with independent replication. The daMCC encodes the context-specific information necessary to convert from count to worth. This encoding is not simply a representation of utility or preference, but the interaction of the two. Specifically, the relationship of brain activation to value is dependent on individual preference, with both positive and negative slopes across the population depending on whether each individual's preference results in enhancement or diminishment of the valuation. For a given value, across participants, enhanced daMCC activation corresponds to diminished subjective valuation, deactivation to enhanced subjective valuation, and non-modulated activation with non-modulated subjective valuation. Further, functional connectivity analyses identified brain regions (positive connectivity with the inferior frontal gyrus and negative connectivity with the nucleus accumbens) through which contextual information may be integrated into the daMCC and allow for outputs to modulate valuation signals. All analyses were replicated through an independent within-study replication, with initial testing in the gains domain and replication in the intermixed and mirrored losses trials. We also present and discuss an ancillary finding: we were unable to identify parametric value signals for losses through whole-brain analyses, and ROI analyses of the vmPFC presented non-modulation across loss value levels. These results identify the neural locus of the value-to-utility transformation, and provide a specific computational function for the daMCC in the production of subjective valuation through the integration of value, context, and preferences.
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What effect do substorms have on the content of the radiation belts? JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2016; 121:6292-6306. [PMID: 27656336 PMCID: PMC5014235 DOI: 10.1002/2016ja022620] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 06/06/2016] [Accepted: 06/08/2016] [Indexed: 06/01/2023]
Abstract
Substorms are fundamental and dynamic processes in the magnetosphere, converting captured solar wind magnetic energy into plasma energy. These substorms have been suggested to be a key driver of energetic electron enhancements in the outer radiation belts. Substorms inject a keV "seed" population into the inner magnetosphere which is subsequently energized through wave-particle interactions up to relativistic energies; however, the extent to which substorms enhance the radiation belts, either directly or indirectly, has never before been quantified. In this study, we examine increases and decreases in the total radiation belt electron content (TRBEC) following substorms and geomagnetically quiet intervals. Our results show that the radiation belts are inherently lossy, shown by a negative median change in TRBEC at all intervals following substorms and quiet intervals. However, there are up to 3 times as many increases in TRBEC following substorm intervals. There is a lag of 1-3 days between the substorm or quiet intervals and their greatest effect on radiation belt content, shown in the difference between the occurrence of increases and losses in TRBEC following substorms and quiet intervals, the mean change in TRBEC following substorms or quiet intervals, and the cross correlation between SuperMAG AL (SML) and TRBEC. However, there is a statistically significant effect on the occurrence of increases and decreases in TRBEC up to a lag of 6 days. Increases in radiation belt content show a significant correlation with SML and SYM-H, but decreases in the radiation belt show no apparent link with magnetospheric activity levels.
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Divergence and Convergence of Risky Decision Making Across Prospective Gains and Losses: Preferences and Strategies. Front Neurosci 2015; 9:457. [PMID: 26733779 PMCID: PMC4679874 DOI: 10.3389/fnins.2015.00457] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 11/16/2015] [Indexed: 11/13/2022] Open
Abstract
People choose differently when facing potential gains than when facing potential losses. Clear gross differences in decision making between gains and losses have been empirically demonstrated in numerous studies (e.g., framing effect, risk preference, loss aversion). However, theories maintain that there are strong underlying connections (e.g., reflection effect). We investigated the relationship between gains and losses decision making, examining risk preferences, and choice strategies (the reliance on option information) using a monetary gamble task with interleaved trials. For risk preferences, participants were on average risk averse in the gains domain and risk neutral/seeking in the losses domain. We specifically tested for a theoretically hypothesized correlation between individual risk preferences across the gains and losses domains (the reflection effect), but found no significant relationship in the predicted direction. Interestingly, despite the lack of reflected risk preferences, cross-domain risk preferences were still informative of individual choice behavior. For choice strategies, in both domains participants relied more heavily on the maximizing strategy than the satisficing strategy, with increased reliance on the maximizing strategy in the losses domain. Additionally, while there is no mathematical reliance between the risk preference and strategy metrics, within both domains there were significant relationships between risk preferences and strategies-the more participants relied upon the maximizing strategy the more risk neutral they were (equating value and utility maximization). These results demonstrate the complexity of gains and losses decision making, indicating the apparent contradiction that their underlying cognitive/neural processes are both dissociable and overlapping.
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Overview of recurrent chromosomal losses in retinoblastoma detected by low coverage next generation sequencing. Cancer Genet 2015; 209:57-69. [PMID: 26883451 DOI: 10.1016/j.cancergen.2015.12.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 09/01/2015] [Accepted: 12/03/2015] [Indexed: 12/12/2022]
Abstract
Genes are frequently lost or gained in malignant tumors and the analysis of these changes can be informative about the underlying tumor biology. Retinoblastoma is a pediatric intraocular malignancy, and since deletions in chromosome 13 have been described in this tumor, we performed genome wide sequencing with the Illumina platform to test whether recurrent losses could be detected in low coverage data from DNA pools of Rb cases. An in silico reference profile for each pool was created from the human genome sequence GRCh37p5; a chromosome integrity score and a graphics 40 Kb window analysis approach, allowed us to identify with high resolution previously reported non random recurrent losses in all chromosomes of these tumors. We also found a pattern of gains and losses associated to clear and dark cytogenetic bands respectively. We further analyze a pool of medulloblastoma and found a more stable genomic profile and previously reported losses in this tumor. This approach facilitates identification of recurrent deletions from many patients that may be biological relevant for tumor development.
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Aging and loss decision making: increased risk aversion and decreased use of maximizing information, with correlated rationality and value maximization. Front Hum Neurosci 2015; 9:280. [PMID: 26029092 PMCID: PMC4429571 DOI: 10.3389/fnhum.2015.00280] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Accepted: 04/28/2015] [Indexed: 12/03/2022] Open
Abstract
We investigated how adult aging specifically alters economic decision-making, focusing on examining alterations in uncertainty preferences (willingness to gamble) and choice strategies (what gamble information influences choices) within both the gains and losses domains. Within each domain, participants chose between certain monetary outcomes and gambles with uncertain outcomes. We examined preferences by quantifying how uncertainty modulates choice behavior as if altering the subjective valuation of gambles. We explored age-related preferences for two types of uncertainty, risk, and ambiguity. Additionally, we explored how aging may alter what information participants utilize to make their choices by comparing the relative utilization of maximizing and satisficing information types through a choice strategy metric. Maximizing information was the ratio of the expected value of the two options, while satisficing information was the probability of winning. We found age-related alterations of economic preferences within the losses domain, but no alterations within the gains domain. Older adults (OA; 61–80 years old) were significantly more uncertainty averse for both risky and ambiguous choices. OA also exhibited choice strategies with decreased use of maximizing information. Within OA, we found a significant correlation between risk preferences and choice strategy. This linkage between preferences and strategy appears to derive from a convergence to risk neutrality driven by greater use of the effortful maximizing strategy. As utility maximization and value maximization intersect at risk neutrality, this result suggests that OA are exhibiting a relationship between enhanced rationality and enhanced value maximization. While there was variability in economic decision-making measures within OA, these individual differences were unrelated to variability within examined measures of cognitive ability. Our results demonstrate that aging alters economic decision-making for losses through changes in both individual preferences and the strategies individuals employ.
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Neural correlates of risky decision making in anxious youth and healthy controls. Depress Anxiety 2014; 31:591-8. [PMID: 24867804 DOI: 10.1002/da.22276] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 04/02/2014] [Accepted: 04/04/2014] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Pediatric anxiety disorders are chronic and impairing conditions that are characterized by risk aversion and avoidance; however, the neural correlates of decision making under risk in anxious youth remain poorly understood. METHODS Youth with a primary diagnosis of separation anxiety, social phobia, or generalized anxiety disorder (n = 16) and healthy controls (n = 15), performed a risky decision-making task under conditions of potential gain or loss while undergoing a functional magnetic resonance imaging (fMRI) scan. RESULTS Analyses were conducted to examine neural response to risky versus nonrisky choices in each condition. Anxious youth made fewer risky choices during potential loss compared to controls. Both groups elicited strong frontostriatal activation during risky choice. During risky choice in the gain condition, controls exhibited greater activation in ventral putamen during risky choice than during nonrisky choice and than anxious youth. In the loss condition, controls exhibited greater activation in medial prefrontal cortex during risk-taking while anxious youth exhibited greater engagement of amygdala and insula. Neural activation during risky choice was associated with individual differences in anxiety symptom severity, such that as anxiety symptomatology increased, there was decreased recruitment of the ventral striatum in the gain condition and increasing recruitment of the amygdala in the loss condition. CONCLUSIONS Youth with anxiety disorders differ from their nonanxious peers on both behavioral and neurobiological indices during risky decision making; these differences are exacerbated by symptom severity and they shed light on the pathophysiology of pediatric anxiety. Neural correlates of risky decision making in anxious youth and healthy controls.
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Contrasting losses and gains increases the predictability of behavior by frontal EEG asymmetry. Front Behav Neurosci 2014; 8:149. [PMID: 24817845 PMCID: PMC4012214 DOI: 10.3389/fnbeh.2014.00149] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 04/12/2014] [Indexed: 11/13/2022] Open
Abstract
Frontal asymmetry measured at rest using EEG is considered a stable marker of approach-avoidance behaviors and risk taking. We examined whether without salient cues of attention in the form of losses, predictability is reduced. Fifty-seven participants performed an experiential decision task in a gain-only, loss-only, and mixed (gains and losses) condition. Increased risk taking on the part of individuals with relatively high left frontal activation, as denoted by the Alpha band, was only observed in the task involving both gains and losses. Event-related potential analysis sheds light on the processes leading to this pattern. Left-frontal dominant individuals had increased fronto-central P300 activation following risky compared to safe outcomes, while right-frontal dominant individuals did not show a P300 difference following safe and risky outcomes. This interaction also only emerged when losses were contrasted with gains. The findings highlight the sensitivity of behavioral predictability to cues of valence.
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Abstract
The present study examined delay and probability discounting of hypothetical monetary losses over a wide range of amounts (from $20 to $500,000) in order to determine how amount affects the parameters of the hyperboloid discounting function. In separate conditions, college students chose between immediate payments and larger, delayed payments and between certain payments and larger, probabilistic payments. The hyperboloid function accurately described both types of discounting, and amount of loss had little or no systematic effect on the degree of discounting. Importantly, the amount of loss also had little systematic effect on either the rate parameter or the exponent of the delay and probability discounting functions. The finding that the parameters of the hyperboloid function remain relatively constant across a wide range of amounts of delayed and probabilistic loss stands in contrast to the robust amount effects observed with delayed and probabilistic rewards. At the individual level, the degree to which delayed losses were discounted was uncorrelated with the degree to which probabilistic losses were discounted, and delay and probability loaded on two separate factors, similar to what is observed with delayed and probabilistic rewards. Taken together, these findings argue that although delay and probability discounting involve fundamentally different decision-making mechanisms, nevertheless the discounting of delayed and probabilistic losses share an insensitivity to amount that distinguishes it from the discounting of delayed and probabilistic gains.
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Chromosomal gains and losses in primary colorectal carcinomas detected by CGH and their associations with tumour DNA ploidy, genotypes and phenotypes. Br J Cancer 1999; 80:526-35. [PMID: 10408863 PMCID: PMC2362312 DOI: 10.1038/sj.bjc.6690388] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Comparative genomic hybridization (CGH) is used to detect amplified and/or deleted chromosomal regions in tumours by mapping their locations on normal metaphase chromosomes. Forty-five sporadic colorectal carcinomas were screened for chromosomal aberrations using direct CGH. The median number of chromosomal aberrations per tumour was 7.0 (range 0-19). Gains of 20q (67%) and losses of 18q (49%) were the most frequent aberrations. Other recurrent gains of 5p, 6p, 7, 8q, 13q, 17q, 19, X and losses of 1p, 3p, 4, 5q. 6q, 8p, 9p, 10, 15q, 17p were found in > 10% of colorectal tumours. High-level gains (ratio > 1.5) were seen only on 8q, 13q, 20 and X, and only in DNA aneuploid tumours. DNA aneuploid tumours had significantly more chromosomal aberrations (median number per tumour of 9.0) compared to diploid tumours (median of 1.0) (P < 0.0001). The median numbers of aberrations seen in DNA hyperdiploid and highly aneuploid tumours were not significantly different (8.5 and 11.0 respectively; P = 0.58). Four tumours had no detectable chromosomal aberrations and these were DNA diploid. A higher percentage of tumours from male patients showed Xq gain and 18q loss compared to tumours from female patients (P = 0.05 and 0.01 respectively). High tumour S phase fractions were associated with gain of 20q13 (P = 0.03), and low tumour apoptotic indices were associated with loss of 4q (P = 0.05). Tumours with TP53 mutations had more aberrations (median of 9.0 per tumour) compared to those without (median of 2.0) (P = 0.002), and gain of 8q23-24 and loss of 18qcen-21 were significantly associated with TP53 mutations (P = 0.04 and 0.02 respectively). Dukes' C/D stage tumours tended to have a higher number of aberrations per tumour (median of 10.0) compared to Dukes' B tumours (median of 3.0) (P = 0.06). The low number of aberrations observed in DNA diploid tumours compared to aneuploid tumours suggests that genomic instability and possible growth advantages in diploid tumours do not result from acquisition of gross chromosomal aberrations but rather from selection for other types of mutations. Our study is consistent with the idea that these two groups of tumours evolve along separate genetic pathways and that gross genomic instability is associated with TP53 gene aberrations.
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