scholarly journals Nonlinear Actuation of Casimir Oscillators toward Chaos: Comparison of Topological Insulators and Metals

Universe ◽  
2021 ◽  
Vol 7 (5) ◽  
pp. 123
Author(s):  
Fatemeh Tajik ◽  
Zahra Babamahdi ◽  
Mehdi Sedighi ◽  
George Palasantzas
Keyword(s):  
Casimir Force ◽  
Chaotic Behavior ◽  
Phase Portraits ◽  
Surface Conductance ◽  
Stable Operation ◽  
Casimir Forces ◽  
Driven Systems ◽  
Operation Conditions ◽  
Increased Risk

In the current study, we explore the sensitivity of the actuation dynamics of electromechanical systems on novel materials, e.g., Bi2Se3, which is a well-known 3D Topological Insulator (TI), and compare their response to metallic conductors, e.g., Au, that are currently used in devices. Bifurcation and phase portraits analysis in conservative systems suggest that the strong difference between the conduction states of Bi2Se3 and Au yields sufficiently weaker Casimir force to enhance stable operation. Furthermore, for nonconservative driven systems, the Melnikov function and Poincare portrait analysis probed the occurrence of chaotic behavior leading to increased risk for stiction. It was found that the presence of the TI enhanced stable operation against chaotic behavior over a significantly wider range of operation conditions in comparison to typical metallic conductors. Therefore, the use of TIs can allow sufficient surface conductance to apply electrostatic compensation of residual contact potentials and, at the same time, to yield sufficiently weak Casimir forces favoring long-term stable actuation dynamics against chaotic behavior.

Sensitivity of Casimir oscillators on geometry and optical properties

2020 ◽  
Vol 35 (03) ◽  
pp. 2040003
Author(s):  
M. Sedighi ◽  
F. Tajik ◽  
S. M. Mahmoudi ◽  
M. H. Nazarpak ◽  
G. R. R. Lamouki ◽  
...  
Keyword(s):  
Optical Properties ◽  
Chaotic Behavior ◽  
Phase Portraits ◽  
Nanoelectromechanical Systems ◽  
Casimir Forces ◽  
Periodically Driven ◽  
The Stability ◽  
Long Term Prediction ◽  
Plate Geometry

The dependence of the Casimir force on the optical properties and geometry of interacting materials makes possible to tailor the actuation dynamics of micro/nano actuators. In this research, we study the dynamical sensitivity of micro- and nanoelectromechanical systems on geometry by comparing the plate-plate and sphere-plate configurations, and taking into account the optical properties of the interacting materials. In fact, for conservative systems bifurcation analysis and phase portraits show that the geometry and the optical properties strongly influence the stability of an actuating device in a way that geometries that lead to weaker Casimir forces (sphere-plate geometry) favor more stable behavior. In addition, for non-conservative periodically driven systems, the Melnikov and Poincare portrait analysis shows that stronger Casimir forces lead to increased chaotic behavior, which more pronounced for the plate-plate geometry, that prohibits the long term prediction of the actuating dynamics of the system.

Long-Term Unemployment in Poland in 2008-2012 - Tendencies, Structure and Selected Determinants

2013 ◽  
Vol 8 (4) ◽  
pp. 347-359
Author(s):  
Leszek Kucharski
Keyword(s):  
Secondary Education ◽  
Young People ◽  
Level Of Education ◽  
Low Level ◽  
Increased Risk

This study presents the structure and tendencies in long-term unemployment in Poland in the years 2008-2012. This study identifies the groups of people with an increased risk of long-term unemployment. The analyses produced the following conclusions. The groups with the highest risk of long-term unemployment include: singles, people aged of 55 and above and people with a low level of education. Young people with university and general secondary education faced the lowest risk of long-term unemployment. 

Casimir forces and vacuum energy

2017 ◽  
Author(s):  
Serge Reynaud ◽  
Astrid Lambrecht
Keyword(s):  
Casimir Force ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Thermal Fluctuations ◽  
Model Systems ◽  
Vacuum Field ◽  
Force Measurements ◽  
Casimir Forces ◽  
Current State ◽  
Field Fluctuations

The Casimir force is an effect of quantum vacuum field fluctuations, with applications in many domains of physics. The ideal expression obtained by Casimir, valid for perfect plane mirrors at zero temperature, has to be modified to take into account the effects of the optical properties of mirrors, thermal fluctuations, and geometry. After a general introduction to the Casimir force and a description of the current state of the art for Casimir force measurements and their comparison with theory, this chapter presents pedagogical treatments of the main features of the theory of Casimir forces for one-dimensional model systems and for mirrors in three-dimensional space.

scholarly journals Occasional and persistent frequent attenders and sickness absences in occupational health primary care: a longitudinal study in Finland

BMJ Open ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. e024980 ◽  
Author(s):  
Tiia T M Reho ◽  
Salla A Atkins ◽  
Nina Talola ◽  
Markku P T Sumanen ◽  
Mervi Viljamaa ◽  
...  
Keyword(s):  
Primary Care ◽  
Longitudinal Study ◽  
Occupational Health ◽  
Sick Leave ◽  
Diagnostic Codes ◽  
Frequent Attenders ◽  
Frequent Attendance ◽  
Increased Risk ◽  
Working Age

ObjectivesFrequent attenders (FAs) create a substantial portion of primary care workload but little is known about FAs’ sickness absences. The aim of the study is to investigate how occasional and persistent frequent attendance is associated with sickness absences among the working population in occupational health (OH) primary care.Setting and participantsThis is a longitudinal study using medical record data (2014–2016) from an OH care provider in Finland. In total, 59 676 patients were included and categorised into occasional and persistent FAs or non-FAs. Sick-leave episodes and their lengths were collected along with associated diagnostic codes. Logistic regression was used to analyse associations between FA status and sick leaves of different lengths (1–3, 4–14 and ≥15 days).ResultsBoth occasional and persistent FA had more and longer duration of sick leave than non-FA through the study years. Persistent FAs had consistently high absence rates. Occasional FAs had elevated absence rates even 2 years after their frequent attendance period. Persistent FAs (OR=11 95% CI 7.54 to 16.06 in 2016) and occasional FAs (OR=2.95 95% CI 2.50 to 3.49 in 2016) were associated with long (≥15 days) sickness absence when compared with non-FAs. Both groups of FAs had an increased risk of long-term sick leaves indicating a risk of disability pension.ConclusionBoth occasional and persistent FAs should be identified in primary care units caring for working-age patients. As frequent attendance is associated with long sickness absences and possibly disability pensions, rehabilitation should be directed at this group to prevent work disability.

Epidemiological Evidence that Maternal Influenza Contributes to the Aetiology of Schizophrenia

1993 ◽  
Vol 163 (4) ◽  
pp. 522-534 ◽  
Author(s):  
W. Adams ◽  
R. E. Kendell ◽  
E. H. Hare ◽  
P. Munk-Jørgensen
Keyword(s):  
Data Sets ◽  
Time Lags ◽  
Epidemiological Evidence ◽  
Intrauterine Development ◽  
Increased Risk ◽  
Schizophrenic Patients ◽  
The Relationship ◽  
Monthly Incidence ◽  
Maternal Influenza

The epidemiological evidence that the offspring of women exposed to influenza in pregnancy are at increased risk of schizophrenia is conflicting. In an attempt to clarify the issue we explored the relationship between the monthly incidence of influenza (and measles) in the general population and the distribution of birth dates of three large series of schizophrenic patients - 16 960 Scottish patients born in 1932–60; 22 021 English patients born in 1921–60; and 18 723 Danish patients born in 1911–65. Exposure to the 1957 epidemic of A2 influenza in midpregnancy was associated with an increased incidence of schizophrenia, at least in females, in all three data sets. We also confirmed the previous report of a statistically significant long-term relationship between patients' birth dates and outbreaks of influenza in the English series, with time lags of - 2 and - 3 months (the sixth and seventh months of pregnancy). Despite several other negative studies by ourselves and others we conclude that these relationships are probably both genuine and causal; and that maternal influenza during the middle third of intrauterine development, or something closely associated with it, is implicated in the aetiology of some cases of schizophrenia.

scholarly journals Paternal and maternal long-term psychological outcomes after uterine artery embolization for severe post-partum hemorrhage

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Maude Bernasconi ◽  
Béatrice Eggel-Hort ◽  
Antje Horsch ◽  
Yvan Vial ◽  
Alban Denys ◽  
...  
Keyword(s):  
Post Traumatic Stress Disorder ◽  
Traumatic Stress ◽  
Uterine Artery Embolization ◽  
Stress Disorder ◽  
Post Partum ◽  
Post Traumatic Stress ◽  
Artery Embolization ◽  
Increased Risk ◽  
Post Traumatic

AbstractThis study intend to compare the long-term psychological impact (depression, post-traumatic stress disorder) on both partners between patients that underwent uterine artery embolization (UAE) for post-partum hemorrhage (PPH) and uneventful deliveries. Women who experienced severe PPH treated by UAE in our institution between 2003 and 2013 were identified in our obstetrical database. These cases were matched to controls with uneventful deliveries. Matching criteria were maternal age, parity, ethnicity, year of delivery, birthweight, gestational age and mode of delivery. Patients and their partners completed validated questionnaires measuring post-traumatic stress (TSQ), as well as depression symptoms (MINI). A total of 63 cases of PPH and 189 matched controls (1:3) participated in a study exploring gynecological and obstetrical outcomes. With a mean of 8 years post-index delivery, patients after PPH showed increased risk of depression (p = 0.015) and post-traumatic stress disorder (22.2% versus 4.8%, p < 0.005) compared to controls. PPH remains strongly associated with post-traumatic stress disorder, even after adjustment for depression (adjusted odds ratio 5.1; 95% confidence intervals 1.5–17.5). Similarly, partners of patients with PPH showed a propensity to depression (p = 0.029) and post-traumatic stress disorder (11.5% versus 1.5%, p = 0.019). In conclusion, both women and their partners are at increased risk of long-term psychological adverse outcomes after PPH. Couples may benefit from psychological support.

scholarly journals Long term alterations of growth after antenatal steroids in preterm twin pregnancies

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Thorsten Braun ◽  
Vivien Filleböck ◽  
Boris Metze ◽  
Christoph Bührer ◽  
Andreas Plagemann ◽  
...  
Keyword(s):  
Early Childhood ◽  
Disease Risk ◽  
Later Life ◽  
Ponderal Index ◽  
Childhood Growth ◽  
Antenatal Steroids ◽  
Increased Risk ◽  
Infancy And Early Childhood ◽  
Twin Pregnancies

AbstractObjectivesTo compare the long-term effects of antenatal betamethasone (ANS, ≤16 mg, =24 mg and >24 mg) in twins on infant and childhood growth.MethodsA retrospective cohort follow up study among 198 twins after ANS including three time points: U1 first neonatal examination after birth and in the neonatal period; U7 examination from the 21st to the 24th month of life and U9 examination from the 60th to the 64th month of life using data from copies of the children’s examination booklets. Inclusion criteria are twin pregnancies with preterm labor, cervical shortening, preterm premature rupture of membranes, or vaginal bleeding, and exposure to ANS between 23+5 and 33+6 weeks. Outcome measures are dosage-dependent and sex-specific effects of ANS on growth (body weight, body length, head circumference, body mass index and ponderal index) up to 5.3 years.ResultsOverall, 99 live-born twin pairs were included. Negative effects of ANS on fetal growth persisted beyond birth, altered infant and childhood growth, independent of possible confounding factors. Overall weight percentile significantly decreased between infancy and early childhood by 18.8%. Birth weight percentiles significantly changed in a dose dependent and sex specific manner, most obviously in female-female and mixed pairs. The ponderal index significantly decreased up to 42.9%, BMI index increased by up to 33.8%.ConclusionsANS results in long-term alterations in infant and childhood growth. Changes between infancy and early childhood in ponderal mass index and BMI, independent of dose or twin pair structure, might indicate an ANS associated increased risk for later life disease.SynopsisFirst-time report on long-term ANS administration growth effects in twin pregnancies, showing persisting alterations beyond birth in infant and childhood growth up to 5.3 years as potential indicator of later life disease risk.

scholarly journals Long-Term Physical Health Outcomes of Resettled Refugee Populations in the United States: A Scoping Review

2021 ◽  
Author(s):  
Gayathri S. Kumar ◽  
Jenna A. Beeler ◽  
Emma E. Seagle ◽  
Emily S. Jentes
Keyword(s):  
Health Outcomes ◽  
Physical Health ◽  
Public Health Practice ◽  
The United States ◽  
Inclusion Criteria ◽  
Physical Health Outcomes ◽  
Increased Risk ◽  
The Us ◽  
Bhutanese Refugee

AbstractSeveral studies describe the health of recently resettled refugee populations in the US beyond the first 8 months after arrival. This review summarizes the results of these studies. Scientific articles from five databases published from January 2008 to March 2019 were reviewed. Articles were included if study subjects included any of the top five US resettlement populations during 2008–2018 and if data described long-term physical health outcomes beyond the first 8 months after arrival in the US. Thirty-three studies met the inclusion criteria (1.5%). Refugee adults had higher odds of having a chronic disease compared with non-refugee immigrant adults, and an increased risk for diabetes compared with US-born controls. The most commonly reported chronic diseases among Iraqi, Somali, and Bhutanese refugee adults included diabetes and hypertension. Clinicians should consider screening and evaluating for chronic conditions in the early resettlement period. Further evaluations can build a more comprehensive, long-term health profile of resettled refugees to inform public health practice.

scholarly journals Postoperative acute kidney injury in adult non-cardiac surgery: joint consensus report of the Acute Disease Quality Initiative and PeriOperative Quality Initiative

2021 ◽  
Author(s):  
John R. Prowle ◽  
Lui G. Forni ◽  
Max Bell ◽  
Michelle S. Chew ◽  
Mark Edwards ◽  
...  
Keyword(s):  
Chronic Kidney Disease ◽  
Acute Kidney Injury ◽  
Cardiac Surgery ◽  
Kidney Disease ◽  
Kidney Injury ◽  
Adverse Outcomes ◽  
Baseline Risk ◽  
Major Surgery ◽  
Increased Risk

AbstractPostoperative acute kidney injury (PO-AKI) is a common complication of major surgery that is strongly associated with short-term surgical complications and long-term adverse outcomes, including increased risk of chronic kidney disease, cardiovascular events and death. Risk factors for PO-AKI include older age and comorbid diseases such as chronic kidney disease and diabetes mellitus. PO-AKI is best defined as AKI occurring within 7 days of an operative intervention using the Kidney Disease Improving Global Outcomes (KDIGO) definition of AKI; however, additional prognostic information may be gained from detailed clinical assessment and other diagnostic investigations in the form of a focused kidney health assessment (KHA). Prevention of PO-AKI is largely based on identification of high baseline risk, monitoring and reduction of nephrotoxic insults, whereas treatment involves the application of a bundle of interventions to avoid secondary kidney injury and mitigate the severity of AKI. As PO-AKI is strongly associated with long-term adverse outcomes, some form of follow-up KHA is essential; however, the form and location of this will be dictated by the nature and severity of the AKI. In this Consensus Statement, we provide graded recommendations for AKI after non-cardiac surgery and highlight priorities for future research.

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