470 research outputs found
Enhanced self-collimation effect by low rotational symmetry in hexagonal lattice photonic crystals
In this study, we present the design of a photonic crystal (PC) structure
with a hexagonal lattice, where adjustments to the PC unit cell symmetry reveal
an all-angle self-collimation (SC) effect. By optimizing opto-geometric
parameters, such as the rotational angle of auxiliary rods and adjacent
distances, we analyze the SC property in detail, leveraging group velocity
dispersion (GVD) and third-order dispersion (TOD) characteristics. We also
investigate the relationship between symmetry properties and their influence on
dispersion characteristics. Through symmetry manipulation, we gain a
comprehensive understanding of the underlying mechanisms governing light
collimation and confinement in the proposed configurations. The PC structure
with a symmetry group exhibits all-angle SC effect within the range of
and normalized frequencies, with a
bandwidth of . Further breaking the symmetry,
transforming from to group symmetry, enhances the SC bandwidth to
and reveals the perfect linear equi-frequency
contours (EFC) at two different frequency bands: all angle SC between
and normalized frequencies in the 4th
transverse magnetic (TM) band and between and
in the 5th TM band. Additionally, we propose a
composite/hybrid PC structure resembling group symmetry, where two
auxiliary rods are replaced by rectangular photonic wires with the same
refractive index and width equal to the diameter of auxiliary rods. This hybrid
structure exhibits an all-angle SC effect with an operating bandwidth of
, displays near-zero GVD and TOD performance
and offers enhanced robustness against potential fabrication precision issues
The first clinical case due to AP92 like strain of Crimean-Congo Hemorrhagic Fever virus and a field survey
<p>Abstract</p> <p>Background</p> <p>Crimean-Congo Hemorrhagic Fever (CCHF) is a fatal infection, but no clinical case due to AP92 strain was reported. We described the first clinical case due to AP92 like CCHFV.</p> <p>Methods</p> <p>A case infected by a AP92 like CCHFV was detected in Balkanian part of Turkey. Diagnosis was confirmed by RT-PCR and sequencing. A human serologic and tick survey studies were performed in the region, where the case detected.</p> <p>Results</p> <p>Thirty eight individuals out of 741 were found to be anti CCHFV IgM positive. The attack rate for overall CCHFV was calculated as 5.2%. In univariate analyses, CCHFV IgM positivity was found to be associated with the age (p < 0.001), male gender (p = 0.001), agricultural activity (p = 0.036), and history of tick bite (p = 0.014). In multivariate analysis, older age (OR: 1.03, CI:1.01–1.05, p < 0.001), male gender were found to be the risk factors (OR: 2.5, CI:1.15–5.63, p = 0.020) for CCHFV infection.</p> <p>Conclusion</p> <p>This is the first human case with AP92 like CCHFV infection. Furthermore, this is the first report of AP92 like strain in Turkey. In the region, elderly males carry the highest risk for CCHFV infection.</p
Quantum Cosmology of Generalized Two--Dimensional Dilaton Gravity Models
The quantum cosmology of two-dimensional dilaton-gravity models is
investigated. A class of models is mapped onto the constrained
oscillator-ghost-oscillator model. A number of exact and approximate solutions
to the corresponding Wheeler-DeWitt equation are presented. A wider class of
minisuperspace models that can be solved in this fashion is identified.
Supersymmetric extensions to the induced gravity theory and the bosonic string
theory are then considered and closed-form solutions to the associated quantum
constraints are derived. The possibility of applying the third-quantization
procedure to two-dimensional dilaton-gravity is briefly discussed.Comment: 28 pages, late
Trend in potassium intake and Na/K ratio in the Italian adult population between the 2008 and 2018 CUORE project surveys
Background and aims: Low potassium intake, in addition to high sodium, has been associated with higher risk of hypertension and CVD. The Study assessed habitual potassium intake and sodium/potassium ratio of the Italian adult population from 2008 to 2012 to 2018–2019 based on 24-h urine collection, in the framework of the CUORE Project/MINISAL-GIRCSI/MENO SALE PIU’ SALUTE national surveys. Methods and results: Data were from cross-sectional surveys of randomly selected age-and-sex stratified samples of resident persons aged 35–74 years in 10 (out of 20) Italian regions. Urinary electrolyte and creatinine measurements were performed in a central laboratory. Analyses considered 942 men and 916 women, examined in 2008–2012, and 967 men and 1010 women, examined in 2018–2019. In 2008–2012, the age-standardized mean of potassium intake (urinary potassium accounts for 70% of potassium intake) was 3147 mg (95% CI 3086–3208) in men and 2784 mg (2727–2841) in women, whereas in 2018–2019, it was 3043 mg (2968–3118) and 2561 mg (2508–2614) respectively. In 2008–2012, age-adjusted prevalence of persons with an adequate potassium intake (i.e. ≥ 3510 mg/day) was 31% (95% CI 28–34%) for men and 18% (16–21%) for women; in 2018–2019, it was 26% (23–29%) and 12% (10–14%) respectively. The sodium/potassium ratio significantly decreased both in men and women. Conclusions: The average daily potassium intake of the Italian general adult population remains lower than the WHO and EFSA recommended level. These results suggest the need of a revision to strengthen initiatives for the promotion of an adequate potassium intake at the population level
Trend of salt intake measured by 24-h urine collection in the Italian adult population between the 2008 and 2018 CUORE project surveys
Background and aims: The WHO Global Action Plan for the Prevention of non-communicable diseases (NCDs) recommends a 30% relative reduction in mean population salt/sodium intake. The study assessed the trend in the habitual salt intake of the Italian adult population from 2008 to 2012 to 2018–2019 based on 24-h urinary sodium excretion, in the framework of the CUORE Project/MINISAL-GIRCSI/MENO SALE PIU’ SALUTE national surveys. Methods and results: Data were from cross-sectional surveys of randomly selected age and sex–stratified samples of resident persons aged 35–74 years in 10 (out of 20) Italian Regions distributed in North, Centre and South of the Country. Urinary sodium and creatinine measurements were carried out in a central laboratory. The analyses included 942 men and 916 women examined in 2008–2012, and 967 men and 1010 women examined in 2018–2019. The age-standardized mean daily population salt (sodium chloride) intake was 10.8 g (95% CI 10.5–11.1) in men and 8.3 g (8.1–8.5) in women in 2008–2012 and respectively 9.5 g (9.3–9.8) and 7.2 g (7.0–7.4) in 2018–2019. A statistically significant (p<0.0001) salt intake reduction was thus observed over 10 years for both genders, and all age, body mass index (BMI) and educational classes. Conclusions: The average daily salt intake of the Italian general adult population remains higher than the WHO recommended level, but a significant reduction of 12% in men and 13% in women has occurred in the past ten years. These results encourage the initiatives undertaken by the Italian Ministry of Health aimed at the reduction of salt intake at the population level
Imported Crimean-Congo hemorrhagic fever cases in Istanbul
We described a series of imported cases of Crimean-Congo Hemorrhagic Fever (CCHF) in Istanbul and investigated the genetic diversity of the virus. All the suspected cases of CCHF, who were applied to the health centers in Istanbul, were screened for CCHF virus (CCHFv) infection by using semi-nested Polymerase Chain Reaction (PCR) following RT-PCR. Simultaneous blood samples were also sent to the national reference laboratory in Ankara for serologic investigation. In 10 out of 91 patients, CCHFv was detected by PCR, and among 9 out of 10, anti-CCHFv IgM antibodies were also positive. Clinical features were characterized by fever, myalgia, and hemorrhage. The levels of liver enzymes, creatinine phosphokinase, and lactate dehydrogenase were elevated, and bleeding markers were prolonged. All the cases were treated with ribavirin. There was no fatal case. All the strains clustered within the same group as other Europe/Turkey isolates
Beyond the jab: A need for global coordination of pharmacovigilance for COVID-19 vaccine deployment Comment
Commentary - No abstract available
Cis P-tau is induced in clinical and preclinical brain injury and contributes to post-injury sequelae
Traumatic brain injury (TBI) is characterized by acute neurological dysfunction and asso- ciated with the development of chronic traumatic encephalopathy (CTE) and Alzheimer’s disease. We previously showed that cis phosphorylated tau (cis P-tau), but not the trans form, contributes to tau pathology and functional impairment in an animal model of severe TBI. Here we found that in human samples obtained post TBI due to a variety of causes, cis P-tau is induced in cortical axons and cerebrospinal fluid and positively correlates with axonal injury and clinical outcome. Using mouse models of severe or repetitive TBI, we showed that cis P-tau elimination with a specific neutralizing antibody administered immediately or at delayed time points after injury, attenuates the development of neuropathology and brain dysfunction during acute and chronic phases including CTE-like pathology and dysfunction after repetitive TBI. Thus, cis P-tau contributes to short-term and long-term sequelae after TBI, but is effectively neutralized by cis antibody treatment
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