319 results on '"S. Segan"'
Search Results
2. Establishing an Alveolar in Vitro Model to Test Potential Pathogenic Aerosols
- Author
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Sandra Stoppelkamp, S. Segan, F. Sollazzo, M. Weber, Christian Schlensak, Tobias Walker, Volker Steger, Mario Lescan, and Hans Peter Wendel
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Pulmonary and Respiratory Medicine ,business.industry ,Medicine ,Surgery ,Cardiology and Cardiovascular Medicine ,business ,Microbiology ,In vitro model ,Test (assessment) - Published
- 2018
- Full Text
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3. Incidence of normal white cell count and C-reactive protein in adults with acute appendicitis
- Author
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Paul Sitzler, Henry H. I. Yao, Nalin H. Dayawansa, Julian D. S. Segan, and Hon Ian Chong
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medicine.medical_specialty ,Abdominal pain ,biology ,business.industry ,Incidence (epidemiology) ,C-reactive protein ,General Medicine ,Emergency department ,030230 surgery ,medicine.disease ,Appendicitis ,Surgery ,Normal white cell count ,03 medical and health sciences ,0302 clinical medicine ,Alvarado score ,Internal medicine ,Acute appendicitis ,medicine ,biology.protein ,030212 general & internal medicine ,medicine.symptom ,business - Abstract
Background Normal C-reactive protein (CRP) and white cell count (WCC) are often used to exclude a diagnosis of acute appendicitis in the Emergency Department (ED). Retrospective review of 281 adult patients with acute appendicitis was performed to study the incidence of normal CRP and WCC on admission and examine any possible predisposing factors. Method Retrospective analysis of patient clinical records yielded CRP, WCC, operative diagnosis, time of symptom onset, imaging results and history and examination features. Case-control analysis was performed with patients with normal CRP and WCC considered the case group and those with raised CRP or WCC considered controls. Groups were compared using Mann-Whitney U-test and chi-squared analysis. Results Of 281 consecutive patients with histologically proven appendicitis, 24 (8.54%) had normal CRP and WCC on presentation to ED. There were no significant differences in age, sex or time to blood collection between groups. Three patients had normal WCC and CRP and an Alvarado score of 4 or less on presentation. Three patients had persistently normal CRP and WCC on repeated testing. There was a trend towards earlier presentation in patients with normal CRP and WCC with 75.0% versus 58.4% presenting within 24 h of symptom onset (OR 2.14, P = 0.112). Conclusion Acute appendicitis remains diagnostically challenging and cannot be excluded on the basis of normal CRP and WCC. Serial clinical and biochemical assessment is warranted in patients with acute abdominal pain, particularly in those presenting early after symptom onset.
- Published
- 2016
- Full Text
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4. Meteoroid environment on the transfer trajectories to Mars
- Author
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Boško Rašuo, Kristina Racković Babić, S. Segan, and Dusan Marceta
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010504 meteorology & atmospheric sciences ,Meteoroid ,Spacecraft ,Mathematical model ,business.industry ,Relative velocity ,Aerospace Engineering ,Flux ,Mars Exploration Program ,Kinematics ,01 natural sciences ,Astrobiology ,Physics::Space Physics ,0103 physical sciences ,Astrophysics::Earth and Planetary Astrophysics ,Aerospace engineering ,business ,Interplanetary spaceflight ,010303 astronomy & astrophysics ,Geology ,0105 earth and related environmental sciences - Abstract
The possibility of meteoroid impact is one of the main threats to the interplanetary missions. Although the meteoroids in the interplanetary space have very small masses, their velocities are extremely large and can produce highly energetic impacts. In this paper, a specific method to analyze the meteoroid environment on the transfer trajectories to Mars has been developed, by determination of the closest approach situation for a large sample of meteoroid orbits. This allows to analyze, not only the integral flux of meteoroids on the spacecraft surfaces, but also the specific kinematics for every single approach and the distributions of important variables such as relative velocity and its projections on specific directions such as instantaneous directions to Mars, Earth, Sun and apex. The obtained results give the quantitative and qualitative estimate of these variables which are separated for different populations of interplanetary meteoroids. The most exposed parts of the spacecraft on the Hohmann transfer to Mars are directed toward Mars, apex and anti-Earth point while the Sun and anti-Sun directions are symmetrically threatened. This gives the frame for the mission design and impact risk assessment and for the development of mathematical models of the behavior of the new spacecraft protection materials under impact loading and also for their experimental examination.
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- 2016
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5. Enhancing dysarthric speech recognition through SepFormer and hierarchical attention network models with multistage transfer learning
- Author
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R. Vinotha, D. Hepsiba, L. D. Vijay Anand, J. Andrew, and R. Jennifer Eunice
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SepFormer-SEGAN ,HAN ,Transformer ,Conformer ,DSR ,Dysarthric speech enhancement ,Medicine ,Science - Abstract
Abstract Dysarthria, a motor speech disorder that impacts articulation and speech clarity, presents significant challenges for Automatic Speech Recognition (ASR) systems. This study proposes a groundbreaking approach to enhance the accuracy of Dysarthric Speech Recognition (DSR). A primary innovation lies in the integration of the SepFormer-Speech Enhancement Generative Adversarial Network (S-SEGAN), an advanced generative adversarial network tailored for Dysarthric Speech Enhancement (DSE), as a front-end processing stage for DSR systems. The S-SEGAN integrates SEGAN’s adversarial learning with SepFormer speech separation capabilities, demonstrating significant improvements in performance. Furthermore, a multistage transfer learning approach is employed to assess the DSR models for both word-level and sentence-level DSR. These DSR models are first trained on a large speech dataset (LibriSpeech) and then fine-tuned on dysarthric speech data (both isolated and augmented). Evaluations demonstrate significant DSR accuracy improvements in DSE integration. The Dysarthric Speech (DS)-baseline models (without DSE), Transformer and Conformer achieved Word Recognition Accuracy (WRA) percentages of 68.60% and 69.87%, respectively. The introduction of Hierarchical Attention Network (HAN) with the Transformer and Conformer architectures resulted in improved performance, with T-HAN achieving a WRA of 71.07% and C-HAN reaching 73%. The Transformer model with DSE + DSR for isolated words achieves a WRA of 73.40%, while that of the Conformer model reaches 74.33%. Notably, the T-HAN and C-HAN models with DSE + DSR demonstrate even more substantial enhancements, with WRAs of 75.73% and 76.87%, respectively. Augmenting words further boosts model performance, with the Transformer and Conformer models achieving WRAs of 76.47% and 79.20%, respectively. Remarkably, the T-HAN and C-HAN models with DSE + DSR and augmented words exhibit WRAs of 82.13% and 84.07%, respectively, with C-HAN displaying the highest performance among all proposed models.
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- 2024
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6. Influence of seasonal cycles in Martian atmosphere on entry, descent and landing sequence
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Dusan Marceta, S. Segan, and Boško Rašuo
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Martian ,Orbital plane ,010504 meteorology & atmospheric sciences ,Equator ,Aerospace Engineering ,Mars Exploration Program ,Atmosphere of Mars ,Atmospheric sciences ,01 natural sciences ,Latitude ,13. Climate action ,0103 physical sciences ,Solstice ,Longitude ,010303 astronomy & astrophysics ,Geology ,0105 earth and related environmental sciences - Abstract
The phenomena like high eccentricity of Martian orbit, obliquity of the orbital plane and close alignment of the winter solstice and the orbital perihelion, separately or together can significantly alter not only the level of some Martian atmospheric parameters but also the characteristics of its diurnal and seasonal cycle. Considering that entry, descent and landing (EDL) sequence is mainly driven by the density profile of the atmosphere and aerodynamic characteristic of the entry vehicle. We have performed the analysis of the influence of the seasonal cycles of the atmospheric parameters on EDL profiles by using Mars Global Reference Atmospheric Model (Mars-GRAM). Since the height of the deployment of the parachute and the time passed from the deployment to propulsion firing (descent time) are of crucial importance for safe landing and the achievable landing site elevation we paid special attention to the influence of the areocentric longitude of the Sun (Ls) on these variables. We have found that these variables have periodic variability with respect to Ls and can be very well approximated with a sine wave function whose mean value depends only on the landing site elevation while the amplitudes and phases depend only on the landing site latitude. The amplitudes exhibit behavior which is symmetric with respect to the latitude but the symmetry is shifted from the equator to the northern mid-tropics. We have also noticed that the strong temperature inversions which are usual for middle and higher northern latitudes while Mars is around its orbital perihelion significantly alter the descent time without influencing the height of the parachute deployment. At last, we applied our model to determine the dependence of the accessible landing region on Ls and found that this region reaches maximum when Mars is around the orbital perihelion and can vary 50° in latitude throughout the Martian year.
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- 2014
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7. Enhancing dysarthric speech recognition through SepFormer and hierarchical attention network models with multistage transfer learning
- Author
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Vinotha, R., Hepsiba, D., Vijay Anand, L. D., Andrew, J., and Jennifer Eunice, R.
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- 2024
- Full Text
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8. Incidence of normal white cell count and C-reactive protein in adults with acute appendicitis
- Author
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Nalin H, Dayawansa, Julian D S, Segan, Henry H I, Yao, Hon I, Chong, and Paul J, Sitzler
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Adult ,Male ,Chi-Square Distribution ,Australia ,Middle Aged ,Appendicitis ,Prognosis ,Severity of Illness Index ,Statistics, Nonparametric ,Tertiary Care Centers ,Leukocyte Count ,Young Adult ,C-Reactive Protein ,Treatment Outcome ,Reference Values ,Risk Factors ,Case-Control Studies ,Acute Disease ,Confidence Intervals ,Appendectomy ,Humans ,Female ,Emergency Service, Hospital ,Retrospective Studies - Abstract
Normal C-reactive protein (CRP) and white cell count (WCC) are often used to exclude a diagnosis of acute appendicitis in the Emergency Department (ED). Retrospective review of 281 adult patients with acute appendicitis was performed to study the incidence of normal CRP and WCC on admission and examine any possible predisposing factors.Retrospective analysis of patient clinical records yielded CRP, WCC, operative diagnosis, time of symptom onset, imaging results and history and examination features. Case-control analysis was performed with patients with normal CRP and WCC considered the case group and those with raised CRP or WCC considered controls. Groups were compared using Mann-Whitney U-test and chi-squared analysis.Of 281 consecutive patients with histologically proven appendicitis, 24 (8.54%) had normal CRP and WCC on presentation to ED. There were no significant differences in age, sex or time to blood collection between groups. Three patients had normal WCC and CRP and an Alvarado score of 4 or less on presentation. Three patients had persistently normal CRP and WCC on repeated testing. There was a trend towards earlier presentation in patients with normal CRP and WCC with 75.0% versus 58.4% presenting within 24 h of symptom onset (OR 2.14, P = 0.112).Acute appendicitis remains diagnostically challenging and cannot be excluded on the basis of normal CRP and WCC. Serial clinical and biochemical assessment is warranted in patients with acute abdominal pain, particularly in those presenting early after symptom onset.
- Published
- 2016
9. The distributions of positions of Minimal Orbit Intersection Distances among Near Earth Asteroids
- Author
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S. Segan and Dusan Marceta
- Subjects
Physics ,Orbital elements ,Atmospheric Science ,Near-Earth object ,Aerospace Engineering ,Astronomy ,Astronomy and Astrophysics ,Astrobiology ,Geophysics ,Intersection ,Space and Planetary Science ,Asteroid ,General Earth and Planetary Sciences ,Orbit (control theory) - Abstract
This paper presents the distributions of the positions of the Minimal Orbit Intersection Distances (MOID) among three subgroups of the Near Earth Asteroids (NEAs). This includes 683 Atens, 4185 Apollos and 3538 Amors which makes over 15 millions combinations of the pairs of orbits. The results which are obtained in this analysis show very interesting distributions of positions of the MOIDs and circumstances of close approaches of the asteroids and emphasize influence of different orbital elements on these distributions.
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- 2012
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10. Possibilities of Improving the TD88 Atmospheric Total Density Model
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Dusan Marceta and S. Segan
- Subjects
Physics ,010504 meteorology & atmospheric sciences ,Density model ,lcsh:Astronomy ,Astronomy and Astrophysics ,Earth ,Function (mathematics) ,01 natural sciences ,lcsh:QB1-991 ,Theoretical physics ,0103 physical sciences ,Statistical physics ,Thermosphere ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences - Abstract
In this paper we have examined possibilities for preserving and improving the total density model of the Earth?s neutral thermosphere TD88 (Sehnal and Posp?silov? 1988) via modelling differences between TD88 and NRLMSISE-00 (Picone et al. 2002), which is used as a control model. It is shown that these residuals can be approximated with polyharmonic function. Starting from this we have developed the mathematical model of the residuals to identify their origin and possibilities to improve the TD88 model itself.
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- 2010
11. The $\Sigma-{\sf \textit D}$ relation for planetary nebulae
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Dejan Urošević, S. Segan, Branislav Vukotić, Dragana Ilic, Miroslav Filipovic, Bojan Arbutina, S. Vidojevic, and Ivan S. Bojičić
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Physics ,010308 nuclear & particles physics ,Astrophysics::High Energy Astrophysical Phenomena ,Star (game theory) ,Bremsstrahlung ,Order (ring theory) ,Sigma ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Planetary nebula ,Space and Planetary Science ,0103 physical sciences ,Surface brightness ,Supernova remnant ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Malmquist bias - Abstract
We present an extended analysis of the relation between radio surface brightness and diameter -- the so-called $\Sigma-D$ relation for planetary nebulae (PNe). We revise our previous derivation of the theoretical $\Sigma-D$ relation for the evolution of bremsstrahlung surface brightness in order to include the influence of the fast wind from the central star. Different theoretical forms are derived: $\Sigma \propto D^{-1}$ for the first and second phases of evolution and $\Sigma\propto D^{-3}$ for the final stage of evolution. Also, we analyzed several different Galactic PN samples. All samples are influenced by severe selection effects, but Malmquist bias seems to be less influential here than in the supernova remnant (SNR) samples. We derived empirical $\Sigma-D$ relations for 27 sample sets using 6 updated PN papers from which an additional 21 new sets were extracted. Twenty four of these have a trivial form of $\beta \approx 2$. However, we obtain one empirical $\Sigma-D$ relation that may be useful for determining distances to PNe. This relation is obtained by extracting a recent nearby (< 1 kpc) Galactic PN sample.
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- 2009
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12. TD-88Up: Upgraded neutral Earth's thermosphere total density TD-88 model
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S. Segan and B. Surlan
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Atmospheric air ,Physics ,010504 meteorology & atmospheric sciences ,lcsh:Astronomy ,Earth ,Astronomy and Astrophysics ,Model parameters ,Atmospheric sciences ,01 natural sciences ,7. Clean energy ,Geomagnetic index ,lcsh:QB1-991 ,13. Climate action ,Control data ,Physics::Space Physics ,0103 physical sciences ,Range (statistics) ,Thermosphere ,010303 astronomy & astrophysics ,Earth (classical element) ,0105 earth and related environmental sciences - Abstract
Improved constants of the total density TD-88 model for the Earth's neutral thermosphere are calculated. The model is fully functional within the height range of 200 to 500 km, with fixed values of the mean solar flux and geomagnetic index. The control data of the atmospheric air density are derived from the aeronomical NRLMSISE-00 model which was used as the reference one. The upgraded TD-88, named TD-88Up, model is obtained by the extended LSQ method with varying all model parameters.
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- 2009
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13. PR and PL (PMv) relations for classical Cepheids revisited
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S. Segan and P. Glisovic
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Length scale ,Brightness ,010504 meteorology & atmospheric sciences ,Cepheid variable ,lcsh:Astronomy ,Astrophysics::High Energy Astrophysical Phenomena ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,RR Lyrae variable ,Cepheids ,01 natural sciences ,Luminosity ,lcsh:QB1-991 ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Stars: distances ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Physics ,COSMIC cancer database ,Cosmic distance ladder ,Astronomy ,Astronomy and Astrophysics ,Radius ,Stars: statistics - Abstract
Using observational data available for a large number of Galactic Cepheids, we determine the relation between the radius and the period of pulsations, by means of a variant of the Baade-Wesselink method. Using, further, the brightness parameter according to the Barnes-Evans approach, we achieve our final goal, determination of the relation between the period and the mean luminosity. The coefficients in both relations are realistic. We indicate the need for accurate angular diameters of the Cepheids, which would be useful since the Cepheids are standard candles in the cosmic distance scale.
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- 2009
14. DepAstroCCD an original astrometric tool
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R. Pavlovic, I. Stojanovic, S. Segan, and P. Glisovic
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Physics ,lcsh:Astronomy ,business.industry ,Interface (computing) ,Autocorrelation ,Fast Fourier transform ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Techniques: image processing ,Astronomy and Astrophysics ,Astrometry ,Real image ,binaries: visual ,law.invention ,lcsh:QB1-991 ,Telescope ,Optics ,Software ,law ,Computer graphics (images) ,business ,Image gradient - Abstract
A complex software for preparation and treatment of astro photographic plates and double-star observations recorded with CCD cameras is developed. The preparation interface contains a catalogue base for the choice of observation objects and an interface for bringing into accordance the telescope and CCD camera performance with the assumptions of the postprocessor interface. The processing is based on the original development of image gradient removing software and classical FFT method and autocorrelation. The software has been tested on several theoretical and real images of double stars.
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- 2006
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15. Some results regarding the comparison of the Earth's atmospheric models
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B. Surlan and S. Segan
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Physics ,Atmospheric models ,Meteorology ,lcsh:Astronomy ,010308 nuclear & particles physics ,Earth ,Astronomy and Astrophysics ,Accelerometer ,01 natural sciences ,lcsh:QB1-991 ,Atmosphere ,Physics::Space Physics ,0103 physical sciences ,Orbit (dynamics) ,Astrophysics::Earth and Planetary Astrophysics ,010303 astronomy & astrophysics ,Realization (systems) ,Physics::Atmospheric and Oceanic Physics ,Earth (classical element) ,Remote sensing - Abstract
In this paper we examine air densities derived from our realization of aeronomic atmosphere models based on accelerometer measurements from satellites in a low Earth's orbit (LEO). Using the adapted algorithms we derive comparison parameters. The first results concerning the adjustment of the aeronomic models to the total-density model are given.
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- 2005
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16. Earth’s rotation irregularities derived from UTIBLI by method of multi-composing of ordinates
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S. Segan, B. Surlan, and Ivana Damjanov
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methods: numerical - time ,Physics ,010504 meteorology & atmospheric sciences ,lcsh:Astronomy ,business.industry ,Nutation ,Mathematical analysis ,Astronomy and Astrophysics ,Harmonic (mathematics) ,Span (engineering) ,Rotation ,methods: data analysis ,01 natural sciences ,Term (time) ,lcsh:QB1-991 ,Optics ,Ordinate ,0103 physical sciences ,business ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,Earth's rotation - Abstract
Using the method of multi-composing of ordinates we have identified in Earth?s rotation a long-periodic term with a period similar to the relaxation time of Chandler nutation. There was not enough information to assess its origin. We demonstrate that the method can be used even in the case when the data time span is comparable to the period of harmonic component.
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- 2003
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17. Multi-composing of the ordinates as a spectral filter
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B. Surlan, Ivana Damjanov, and S. Segan
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lcsh:QB1-991 ,Physics ,Ordinate ,lcsh:Astronomy ,Filter (video) ,Spectral filtering ,Astronomy and Astrophysics ,Equidistant ,Construct (python library) ,methods: data analysis ,Algorithm ,methods: numerical - Abstract
In this paper we describe a method of plain and multi composing of ordinates to define spectral filters. We apply the method to the simulated equidistant observations, and we find that the suitable filters are easy to construct and apply.
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- 2003
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18. MaxEnt and Marxan modeling to predict the potential habitat and priority planting areas of Coffea arabica in Yunnan, China under climate change scenario.
- Author
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Li, Xia, Wang, Zihao, Wang, Shaoqiang, and Qian, Zhaohui
- Abstract
Introduction: Coffea arabica (Arabica coffee) is an important cash crop in Yunnan, China. Ongoing climate change has made coffee production more difficult to sustain, posing challenges for the region's coffee industry. Predictions of the distribution of potentially suitable habitats for Arabica coffee in Yunnan could provide a theoretical basis for the cultivation and rational management of this species. Methods: In this study, the MaxEnt model was used to predict the potential distribution of suitable habitat for Arabica coffee in Yunnan under current and future (2021-2100) climate scenarios (SSP2-4.5, SSP3-7.0, and SSP5-8.5) using 56 distributional records and 17 environmental variables and to analyze the important environmental factors. Marxan model was used to plan the priority planting areas for this species at last. Results: The predicted suitable and sub-suitable areas were about 4.21×10
4 km2 and 13.87×104 km2 , respectively, accounting for 47.15% of the total area of the province. The suitable areas were mainly concentrated in western and southern Yunnan. The minimum temperature of the coldest month, altitude, mean temperature of the wettest quarter, slope, and aluminum saturation were the main environmental variables affecting the distribution of Arabica coffee in Yunnan Province. Changes in habitat suitability for Arabica coffee were most significant and contracted under the SSP3-7.0 climate scenario, while expansion was highest under the SSP5-8.5 climate scenario. Priority areas for Arabica coffee cultivation in Yunnan Province under the 30% and 50% targets were Pu'er, Xishuangbanna, Honghe, Dehong, and Kunming. Discussion: Climate, soil, and topography combine to influence the potential geographic distribution of Arabica coffee. Future changes in suitable habitat areas under different climate scenarios should lead to the delineation of coffee-growing areas based on appropriate environmental conditions and active policy measures to address climate change. [ABSTRACT FROM AUTHOR]- Published
- 2024
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19. Changing paradigm of malnutrition among Bangladeshi women of reproductive age and gaps in national Nutrition Policies and Action Plans to tackle the emerging challenge.
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Khan, Shusmita, Haider, M. Moinuddin, Jamil, Kanta, Ahsan, Karar Zunaid, Siraj, Saiqa, Iqbal, Afrin, and Angeles, Gustavo
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- 2024
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20. Hyperlactataemia is a marker of reduced exercise capacity in heart failure with preserved ejection fraction.
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Nan Tie, Emilia, Wolsk, Emil, Nanayakkara, Shane, Vizi, Donna, Mariani, Justin, Moller, Jacob Eifer, Hassager, Christian, Gustafsson, Finn, and Kaye, David M.
- Subjects
BLOOD lactate ,AEROBIC capacity ,CHRONIC kidney failure ,HEART failure ,CARDIAC catheterization - Abstract
Aims: Heart failure with preserved ejection fraction (HFpEF) is associated with an array of central and peripheral haemodynamic and metabolic changes. The exact pathogenesis of exercise limitation in HFpEF remains uncertain. Our aim was to compare lactate accumulation and central haemodynamic responses to exercise in patients with HFpEF, non‐cardiac dyspnoea (NCD), and healthy volunteers. Methods and results: Right heart catheterization with mixed venous blood gas and lactate measurements was performed at rest and during symptom‐limited supine exercise. Multivariable analyses were conducted to determine the relationship between haemodynamic and biochemical parameters and their association with exercise capacity. Of 362 subjects, 198 (55%) had HFpEF, 103 (28%) had NCD, and 61 (17%) were healthy volunteers. This included 139 (70%) females with HFpEF, 77 (75%) in NCD (P = 0.41 HFpEF vs. NCD), and 31 (51%) in healthy volunteers (P < 0.001 HFpEF vs. volunteers). The median age was 71 (65, 75) years in HFpEF, 66 (57, 72) years in NCD, and 49 (38, 65) years in healthy volunteers (HFpEF vs. NCD or volunteer, both P < 0.001). Peak workload was lower in HFpEF compared with healthy volunteers [52 W (interquartile range 31–73), 150 W (125–175), P < 0.001], but not NCD [53 W (33, 75), P = 0.85]. Exercise lactate indexed to workload was higher in HFpEF at 0.08 mmol/L/W (0.05–0.11), 0.06 mmol/L/W (0.05–0.08; P = 0.016) in NCD, and 0.04 mmol/L/W (0.03–0.05; P < 0.001) in volunteers. Exercise cardiac index was 4.5 L/min/m2 (3.7–5.5) in HFpEF, 5.2 L/min/m2 (4.3–6.2; P < 0.001) in NCD, and 9.1 L/min/m2 (8.0–9.9; P < 0.001) in volunteers. Oxygen delivery in HFpEF was lower at 1553 mL/min (1175–1986) vs. 1758 mL/min (1361–2282; P = 0.024) in NCD and 3117 mL/min (2667–3502; P < 0.001) in the volunteer group during exercise. Predictors of higher exercise lactate levels in HFpEF following adjustment included female sex and chronic kidney disease (both P < 0.001). Conclusions: HFpEF is associated with reduced exercise capacity secondary to both central and peripheral factors that alter oxygen utilization. This results in hyperlactataemia. In HFpEF, plasma lactate responses to exercise may be a marker of haemodynamic and cardiometabolic derangements and represent an important target for future potential therapies. [ABSTRACT FROM AUTHOR]
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- 2024
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21. Synthesis, in vitro activity, and molecular docking of caffeic acid and resveratrol derivatives against Alzheimer's disease-related enzymes.
- Author
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Martínez, Alberto
- Abstract
Alzheimer's disease (AD) is the most common form of dementia affecting about 40 million people around the world. The number of people living with this ailment is expected to triple in the next 50 years due to the aging population and the lack of any effective treatment. In this work we have synthesized a group of three hybrid caffeic acid and a resveratrol derivatives (1-4), and we have tested their ability to inhibit in vitro the enzymatic activity of the beta-site amyloid precursor protein cleaving protein enzyme 1 (BACE 1) and acetylcholinesterase (AChE). The inhibitory activity was compared to that of parent compounds caffeic acid and resveratrol, as well as related chlorogenic acid. Clinically tested LY2811376 and tacrine were used as positive controls. All three caffeic acid derivatives displayed better inhibitory activity than parent caffeic acid and chlorogenic acid. In particular, the in vitro IC
50 for compound 4 against BACE 1 fell in the nanomolar range (69 ± 5 nM), comparable or better than LY2811376 (173 ± 8 nM) which reached Phase I clinical trials against AD as a BACE 1 inhibitor. On the other hand, compound 3 showed a remarkable AChE inhibitory potency in the low micromolar range (1.93 ± 0.16 μM). Molecular docking was performed to gain valuable insights into the interactions between compounds 1-4 and the active sites of both BACE 1 and AChE. Calculated binding affinities generally correlated well with experimental in vitro inhibition. Experimental and molecular docking results validated the proposed drug design, since the most active compounds 3 and 4 established interactions with relevant amino acid residues of the BACE 1 and AChE active sites through the different pharmacophore features of the hybrid structures. Overall, the results presented in this work could potentially have important implications in the rational design of compounds with potential anti-AD properties. [ABSTRACT FROM AUTHOR]- Published
- 2024
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22. Differential Effect of Sex on Mortality According to Age in Heart Failure.
- Author
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Yoonpyo Lee, Minjae Yoon, Dong-Ju Choi, and Jin Joo Park
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- 2024
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23. Early- to mid-gestational testosterone excess leads to adverse cardiac outcomes in postpartum sheep.
- Author
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Alkhatib, Bashar, Ciarelli, Joseph, Ghnenis, Adel, Pallas, Brooke, Olivier, Nicholas, Padmanabhan, Vasantha, and Vyas, Arpita Kalla
- Subjects
BAX protein ,TUMOR necrosis factors ,TESTOSTERONE ,PUERPERIUM ,STAINS & staining (Microscopy) ,TEENAGE pregnancy - Abstract
Cardiovascular dysfunctions complicate 10–20% of pregnancies, increasing the risk for postpartum mortality. Various gestational insults, including preeclampsia are reported to be associated with adverse maternal cardiovascular outcomes. One such insult, gestational hyperandrogenism increases the risk for preeclampsia and other gestational morbidities but its impact on postpartum maternal health is not well known. We hypothesize that gestational hyperandrogenism such as testosterone (T) excess will adversely impact the maternal heart in the postpartum period. Pregnant ewes were injected with T propionate from day 30 to day 90 of gestation (term 147 days). Three months postpartum, echocardiograms, plasma cytokine profiles, cardiac morphometric, and molecular analysis were conducted [control (C) n = 6, T-treated (T) n = 7 number of animals]. Data were analyzed by two-tailed Student's t test and Cohen's effect size (d) analysis. There was a nonsignificant large magnitude decrease in cardiac output (7.64 ± 1.27 L/min vs. 10.19 ± 1.40, P = 0.22, d = 0.81) and fractional shortening in the T ewes compared with C (35.83 ± 2.33% vs. 41.50 ± 2.84, P = 0.15, d = 0.89). T treatment significantly increased 1) left ventricle (LV) weight-to-body weight ratio (2.82 ± 0.14 g/kg vs. 2.46 ± 0.08) and LV thickness (14.56 ± 0.52 mm vs. 12.50 ± 0.75), 2) proinflammatory marker [tumor necrosis factor-alpha (TNF-α)] in LV (1.66 ± 0.35 vs. 1.06 ± 0.18), 3) LV collagen (Masson's Trichrome stain: 3.38 ± 0.35 vs. 1.49 ± 0.15 and Picrosirius red stain: 5.50 ± 0.32 vs. 3.01 ± 0.23), 4) markers of LV apoptosis, including TUNEL (8.3 ± 1.1 vs. 0.9 ± 0.18), bcl-2-associated X protein (Bax)+-to-b-cell lymphoma 2 (Bcl2)+ ratio (0.68 ± 0.30 vs. 0.13 ± 0.02), and cleaved caspase 3 (15.4 ± 1.7 vs. 4.4 ± 0.38). These findings suggest that gestational testosterone excess adversely programs the maternal LV, leading to adverse structural and functional consequences in the postpartum period. NEW & NOTEWORTHY: Using a sheep model of human translational relevance, this study provides evidence that excess gestational testosterone exposure such as that seen in hyperandrogenic disorders adversely impacts postpartum maternal hearts. [ABSTRACT FROM AUTHOR]
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- 2024
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24. Myocardial Inflammation in Heart Failure With Reduced and Preserved Ejection Fraction.
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Alcaide, Pilar, Kallikourdis, Marinos, Emig, Ramona, and Prabhu, Sumanth D.
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- 2024
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25. Prevenzione di genere: focus sulle malattie cardiache.
- Author
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Ciarambino, Tiziana, Addesi, Desiree, and Crispino, Pietro
- Published
- 2024
26. Obesity Prevalence and Its Impact on Maternal and Neonatal Outcomes among Pregnant Women: A Retrospective Cross-Sectional Study Design.
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AlAnnaz, Wejdan Abdullah A., Gouda, Amel Dawod Kamel, Abou El-Soud, Faiza Ahmed, and Alanazi, Mona R
- Subjects
CROSS-sectional method ,CESAREAN section ,PEARSON correlation (Statistics) ,ANEMIA ,BODY mass index ,BEHAVIOR modification ,GESTATIONAL diabetes ,NEONATAL intensive care units ,PREGNANT women ,PREGNANCY outcomes ,RETROSPECTIVE studies ,DISEASE prevalence ,NEONATAL intensive care ,FETAL macrosomia ,JUDGMENT sampling ,DESCRIPTIVE statistics ,CHI-squared test ,OBESITY in women ,HEALTH behavior ,STATISTICS ,DATA analysis software ,LENGTH of stay in hospitals ,DIET ,DISEASE complications - Abstract
Background: The escalating prevalence of obesity in women of reproductive age raises concerns about its impact on maternal and fetal health during pregnancy. This study aimed to thoroughly assess how obesity affects pregnancy and neonatal outcomes among Saudi pregnant women. Methods: In a retrospective cross-sectional study, we analyzed 8426 pregnant women who delivered at King Fahad National Guard Hospital in Riyadh in 2021. Of these, 3416 had obesity, and 341 of them, meeting the inclusion criteria, were selected. Maternal and neonatal outcomes were compiled using a structured questionnaire and extracted from the hospital's "Best Care" data-based registration system. Results: The findings highlighted that 40.5% of pregnant women were classified as obese, with almost half falling into obesity class II based on BMI. Obesity correlated significantly with adverse maternal outcomes like gestational diabetes and increased rates of cesarean deliveries. Additionally, maternal obesity was linked to unfavorable fetal outcomes, including higher rates of newborn intensive care unit admissions, lower APGAR scores at 1 min, and a greater likelihood of macrosomia. Conclusions: This study underscores the important impact of maternal obesity on both maternal and fetal health during pregnancy. Addressing this high-risk condition demands targeted educational programs for women of reproductive age focusing on BMI control, dietary adjustments, and lifestyle modifications to mitigate obesity-related complications during pregnancy. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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27. Child Telomere Length at 11–12 Years of Age Is Not Associated with Pregnancy Complications.
- Author
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Bianco-Miotto, Tina, Hossain, Sadia, Habibi, Nahal, Haag, Dandara G., and Grieger, Jessica A.
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PREGNANCY complications ,TELOMERES ,GESTATIONAL age ,REPRODUCIBLE research ,REGRESSION analysis - Abstract
Children born from pregnancy complications are at higher risk of chronic diseases in adulthood. Identifying which children born from a complicated pregnancy are likely to suffer from later chronic disease is important in order to intervene to prevent or delay the onset of disease. This study examined the associations between the major pregnancy complications (gestational diabetes, high blood pressure, small- and large for gestational age, and preterm birth) and child telomere length, a biomarker of chronic disease risk. This was a population-based longitudinal analysis using data from the Longitudinal Study of Australian Children. The primary outcome is telomere length, measured in 11–12-year-old children. Multivariable linear regression was used to estimate the association between pregnancy complications and child telomere length, adjusting for a range of a priori confounders. Data from 841 families were used. One in four pregnancies (27.1%) featured a pregnancy complication. In the adjusted analysis, there was no association between pregnancy complications and child telomere length (high blood pressure: mean difference (95% CI): 0.00 (−0.12, 0.12); gestational diabetes (0.05 (−0.10, 0.19)); small for gestational age (0.07 (−0.04, 0.19)); large for gestational age (−0.06 (−0.15, 0.03)); and preterm birth (−0.10 (−0.21, 0.01)). Our results do not support the notion that telomere length is shorter in children born to mothers after a pregnancy complication. Methodological considerations should be rigorous to improve the reproducibility of findings. [ABSTRACT FROM AUTHOR]
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- 2024
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28. Anthropogenic Pressures on Gorillas: A Case of Grauer's Gorillas in Maiko National Park, the Democratic Republic of Congo.
- Author
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Consolee, Kahindo Tulizo, Luan, Xiaofeng, and Cong, Li
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GORILLA (Genus) ,NATIONAL parks & reserves ,FOREST conservation ,HABITATS ,ZOONOSES ,HABITAT modification - Abstract
Anthropogenic activities put biodiversity under pressure, adversely affecting the forest ecosystem and wildlife habitats. Habitat disturbance and modification are among the main threats to animal populations in tropical forests. In the Democratic Republic of Congo (DRC), Grauer's gorillas (Gorilla beringei graueri) are continuously threatened through forest encroachment for agricultural expansion, human settlements, new refugee camps, illegal logging, and mining across the country. Moreover, poaching and bushmeat trafficking continuously threaten gorillas' existence. These drivers increase the proximity of humans and the risk of disease transmission. The emerging and existing zoonotic diseases, including Ebola, are continuously impacting gorillas' lives. All of these pressures combined are disrupting natural behavior patterns and are leading to the decline in the Grauer's gorillas' population. Therefore, this review scrutinizes findings on the anthropogenic pressures on the habitats and survival of Grauer's gorillas. Also, it is important to engage with people for the shared conservation role and ecotourism to support the conservation of forest biodiversity and Grauer's gorillas' habitats, particularly for the Maiko National Park in the DRC. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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29. Association of daily physical activity with pulmonary artery pressure in HFpEF and HFmrEF NYHA class III patients: a pilot trial-feasibility and first results.
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Herrmann EJ, Lange D, Hannig J, Zimmer G, Gruen D, Keller T, Edegran A, Johnson LS, Sossalla S, Guckert M, and Assmus B
- Abstract
Introduction: Supervised physical exercise has been shown to benefit patients with heart failure with preserved/mildly reduced ejection fraction (HFpEF/HfmrEF) by improving symptoms and diastolic function. This study aimed to investigate the correlation between unsupervised daily physical activity and changes in daily pulmonary artery pressure (PAP) in patients with stable NYHA class III heart failure (HF) and left ventricular ejection fraction (LVEF) of 45% or higher., Methods: Daily physical activity was monitored over a 3-month period using a Holter-ECG with an accelerometer that calculated an activity-associated, heart rate-derived metabolic equivalent of task (MET) score. PAP was measured using an implanted sensor in 17 patients., Results: During 3 months of PAP monitoring in parallel with Holter ECG in our HF patients (median age 77 [IQR 72-79.5] years, LVEF 55 [49-56] %, mean cardiac index 1.9 ± 0.3), mean, diastolic, and systolic PAP remained unchanged. Patients engaged in unsupervised daily activity with a mean MET score of 5.0 ± 1.2 and a median daily duration of 41 [13-123] minutes. Intensity of daily activity was associated with a higher diastolic PAP on the following day (R
2 = 0.017, p = 0.003), particularly in female patients and those with pulmonary hypertension (PH) (female: R2 = 0.044, p = 0.002; PH: R2 = 0.024, p = 0.004). Patients with longer daily activity durations had lower systolic and mean PAP (p = 0.038 and p = 0.048) and a similar diastolic PAP (p = 0.053) after 3 months., Conclusions: Tracking changes in daily PAP based on intensity and duration of unsupervised daily activity using implanted sensors and a PocketECG® is feasible. While daily activity duration was not directly linked to diastolic PAP on the first day after daily activity, intensity, especially in female and PH patients, was associated with increased diastolic PAP. In addition, longer daily activity, rather than higher intensity, might be more important for lowering PAP in the long term. Further research in larger trials is warranted to confirm these findings., (© 2024. The Author(s).)- Published
- 2024
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30. Manganese oxide-based mesoporous thin-film electrodes: manganese disproportionation reaction in alkaline media.
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Durukan, Irmak Karakaya, Ulu, Işıl, and Dag, Ömer
- Abstract
In this study, we explore the disproportionation reaction mechanism in alkaline media during the oxygen evolution reaction (OER) utilizing mesoporous electrodes, namely LiMn
2 O4 (m-LMO), Mn3 O4 (m-Mn3 O4 ), and Mn2 P2 O7 (m-MnPP). The electrodes are crafted through the molten salt-assisted self-assembly (MASA) process. The procedure commences with the application of a metal salt(s)–surfactant and metal salt–pyrophosphoric acid–surfactant (where the surfactant is P123) lyotropic liquid crystalline mesophase coating over a FTO surface by employing a clear ethanol or aqueous solution of the ingredients, followed by a subsequent calcination step at 300 °C. The electrodes are characterized by spectroscopic, diffraction, imaging, and electrochemical techniques. At low electrochemical potentials, Mn(III), and at more positive potentials, Mn(VI) disproportionation reactions make these materials highly unstable in alkaline media. The aforementioned degradation processes have been investigated by examination of the electrodes both prior to and after subsequent use in electrochemical measurements in various electrolytes. We found that the degradation process is relatively slow in m-LMO, but elevated in m-Mn3 O4 and m-MnPP electrodes. m-LMO is fully converted into the λ-MnO2 phase upon its oxidation and more robust to decomposition; making it ultra-thin further improves its robustness. However, the m-Mn3 O4 and m-MnPP electrodes behave similarly to each other and degrade more quickly (more pronounced in the latter), by releasing purple-colored permanganate ions into the electrolyte media. A Mn(VI) disproportionation reaction mechanism is suggested using the experimentally gathered spectroscopic, diffraction, and electrochemical data. The formation of Mn(VI) surface species and their electronegativity play vital roles in the disproportionation reaction. [ABSTRACT FROM AUTHOR]- Published
- 2024
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31. A Critical Review of the Synthesis and Applications of Spinel-Derived Catalysts to Bio-Oil Upgrading.
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Yang S, Gu J, Dai B, and Zhang L
- Abstract
The transformation of renewable bio-oil into value-added chemicals and bio-oil through catalytic processes embodies an efficient approach within the realm of advancing sustainable energy. Spinel-based catalysts have garnered significant attention owing to their ability to precisely tune metals within the framework, thereby facilitating adjustments to structural, physical, and electronic properties, coupled with their remarkable thermal stability. This review aims to provide a comprehensive overview of recent advancements in spinel-based catalysts tailored specifically for upgrading bio-oil. Its objective is to shed light on their potential to address the limitations of conventional catalysts, thereby advancing sustainable biofuel production. Initially, a comprehensive analysis is conducted on different metal oxide composites in terms of their similarity and dissimilarity on properties. Subsequently, the synthesis methodologies of spinels are scrutinised and potential avenues for their modification are explored. Following this, an in-depth discussion ensues regarding the utilisation of spinels as catalysts or catalyst precursors for catalytic cracking, ketonisation, catalytic hydrodeoxygenation, steam and aqueous-phase reforming, as well as electrocatalytic upgrading of bio-oil, with a specific emphasis on elucidating their catalytic reactivity, and underlying structure-activity correlation and catalysis mechanisms. Finally, the challenges and potential prospects in utilising spinels for the catalytic valorisation of renewable biofuel are addressed, with a specific focus on the use of machine learning - based approaches to optimise the structure and activity of spinel catalysts. This review aims to provide specific directions for further exploration and maximisation of the spinel catalysts in the bio-oil upgrading field., (© 2024 Wiley-VCH GmbH.)
- Published
- 2024
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32. Sex Differences in Cardiac and Clinical Phenotypes and Their Relation to Outcomes in Patients with Heart Failure.
- Author
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Kawai, Akane, Nagatomo, Yuji, Yukino-Iwashita, Midori, Nakazawa, Ryota, Yumita, Yusuke, Taruoka, Akira, Takefuji, Asako, Yasuda, Risako, Toya, Takumi, Ikegami, Yukinori, Masaki, Nobuyuki, and Adachi, Takeshi
- Subjects
HEART failure patients ,INDIVIDUALIZED medicine ,TREATMENT effectiveness ,PHENOTYPES ,SEX (Biology) - Abstract
Biological sex is one of the major factors characterizing the heart failure (HF) patient phenotype. Understanding sex-related differences in HF is crucial to implement personalized care for HF patients with various phenotypes. There are sex differences in left ventricular (LV) remodeling patterns in the HF setting, namely, more likely concentric remodeling and diastolic dysfunction in women and eccentric remodeling and systolic dysfunction in men. Recently supra-normal EF (snLVEF) has been recognized as a risk of worse outcome. This pathology might be more relevant in female patients. The possible mechanism may be through coronary microvascular dysfunction and sympathetic nerve overactivation from the findings of previous studies. Further, estrogen deficit might play a significant role in this pathophysiology. The sex difference in body composition may also be related to the difference in LV remodeling and outcome. Lower implementation in guideline-directed medical therapy (GDMT) in female HFrEF patients might also be one of the factors related to sex differences in relation to outcomes. In this review, we will discuss the sex differences in cardiac and clinical phenotypes and their relation to outcomes in HF patients and further discuss how to provide appropriate treatment strategies for female patients. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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33. Weight development from childhood to motherhood—embodied experiences in women with pre-pregnancy obesity: a qualitative study.
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Sandsæter, Heidi L., Eik-Nes, Trine Tetlie, Getz, Linn Okkenhaug, Haugdahl, Hege S., Magnussen, Elisabeth Balstad, Rich-Edwards, Janet W., and Horn, Julie
- Subjects
OBESITY ,WEIGHT gain in pregnancy ,BODY weight ,RESEARCH methodology ,INTERVIEWING ,WEIGHT gain ,EXPERIENCE ,MOTHERHOOD ,QUALITATIVE research ,PREGNANCY complications ,RESEARCH funding ,HEALTH behavior ,DESCRIPTIVE statistics ,THEMATIC analysis ,EMOTIONS ,BODY mass index ,BEHAVIOR modification ,CHILDREN - Abstract
Background: Pre-pregnancy obesity increases the risk of perinatal complications. Post-pregnancy is a time of preparation for the next pregnancy and lifestyle advice in antenatal care and postpartum follow-up is therefore recommended. However, behavioral changes are difficult to achieve, and a better understanding of pregnant women's perspectives and experiences of pre-pregnancy weight development is crucial. Methods: We used a qualitative design and conducted semi-structured interviews with 14 women in Norway with pre-pregnancy obesity 3–12 months postpartum. Data were analyzed using thematic analysis. Results: Four themes addressing women's experiences and understanding of their weight development were generated: (1) Unmet essential needs, (2) Genetic predisposition for obesity, challenging life course transitions and turning points, (3) Under a critical eye: an ever-present negative bodily awareness, and (4) Wrestling with food. Parents' inability to meet children's essential needs caused weight gain through an unbalanced diet, increased stress, and emotional eating patterns. Body criticism and a feeling of not belonging led to negative body awareness that influenced behavioral patterns and relationships. Participants reporting having had a good childhood more often described their weight development as a result of genetic predisposition, challenging life course transitions and turning points, such as illness and injuries. Nevertheless, these participants also described how eating patterns were influenced by stress and negative emotions. Conclusions: Healthcare providers should pay attention to the insider perspectives of pre-pregnancy weight development. An open and shared understanding of the root causes of these women's weight development can form a basis for more successful lifestyle guidance. Plain English summary: Pregnant women with obesity face increased risks of pregnancy-related complications, warranting extended monitoring of their lifestyle and weight during pregnancy. The complexity of obesity makes lifestyle changes challenging both during and beyond pregnancy. Limited research exists on understanding weight development from the perspective of pregnant women with obesity. To explore their understanding and experiences of weight development from childhood to motherhood, we conducted in-depth interviews with 14 women with a BMI ≥ 30 before their pregnancies. The interviews were preformed 3–12 months post-birth. Through thematic analysis, four themes were developed: (1) Unmet essential needs, (2) Genetic predisposition for obesity, challenging life course transitions, and turning points, (3) Under a critical eye: an ever-present negative bodily awareness, and (4) Wrestling with food. Parental neglect of their children's essential needs may result in unhealthy weight gain through an unbalanced diet and/or an urgent need to regulate negative emotions with food. Body criticism and self-perceived differences deprive children and adolescents of a carefree and accepting relationship with their bodies. While participants with a satisfactory childhood more often understood their weight in light of hereditary factors, difficult transitional phases, illness, or injuries, several of them described an eating pattern influenced by negative emotions such as stress, work pressure, and depressed mood. An open and shared understanding of the root causes of these women's weight development can form a basis for more successful lifestyle guidance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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34. Etiology, consequences, and solutions of working women's work-life conflict: a qualitative study.
- Author
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Hosseini, Zahra, Rahimi, Seyyede Fateme, Salmani, Fatemeh, Miri, Mohammad Reza, Aghamolaei, Teamur, and Dastjerdi, Reza
- Subjects
WORK-life balance ,WOMEN employees ,PERSONNEL management ,ROLE conflict ,QUALITY of work life ,QUALITATIVE research - Abstract
Introduction: Work-life conflict (WLC) is important in organizational behavior research and human resource management. The present research aimed to investigate the underlying causes, consequences, and solutions to WLC in Iranian working women. Materials and methods: The present qualitative study was conducted through a content analysis method among 19 working married women in Birjand, a city in the east of Iran, from December 2021 to February 2022. To collect the data, semi-structured interviews were held. The average interview time was 45 minutes, and all interviews were recorded upon the participants' consent. Finally, after coding, the information was analyzed with MAXQDA software. Findings: The causes of conflict included 4 main categories of individual, interpersonal, organizational, and cultural factors, with seven subcategories: the pressure of the mother's role at home, personality traits, lack of individual skills, insufficient support, work characteristics, organizational policies, and the traditional role of women in society. The consequences of conflict included 2 main categories, Decreasing quality of life and work problems with 4 subcategories: physical and mental illnesses, forgetting one's role towards others, limiting social communication, and reducing productivity. Conflict resolution methods included 3 main classes of individual-oriented, other-oriented, and organization-oriented with 8 subclasses: program-oriented, meaning-oriented, emotion-oriented, avoidance, emotional support, instrumental and work support, support work policies, and correct management views. Conclusion: To solve the problem of conflict, different aspects should be considered and help to solve this challenge by influencing each dimension. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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35. Evaluating the Impact of Environmental Performance and Socioeconomic and Demographic Factors on Land Use and Land Cover Changes in Kibira National Park, Burundi.
- Author
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Nyirarwasa, Anathalie, Han, Fang, Yang, Zhaoping, Mperejekumana, Philbert, Dufatanye Umwali, Edovia, Nsengiyumva, Jean Nepo, and Habibulloev, Sharifjon
- Abstract
In Kibira National Park, Burundi, socioeconomic and demographic factors lead to environmental performance challenges that impede biodiversity; thus, understanding the impact of these determinants on land use and land cover change is important to address these challenges. In this study, a multivariate analysis of variance (MANOVA) model was used to quantify the impact of socioeconomic and demographic factors on land cover/land use (LCLU) changes using Landsat images captured between 1990 and 2021. In addition, the impact of the environmental performance index (EPI), particularly ecosystem vitality (ECO), on landscape fragmentation was examined using a Spearman correlation analysis. A Pearson correlation analysis and a principal component analysis (PCA) were used to investigate the connections between the indicators of relevance in this study. The results reveal a decrease in forestland from 86.1% to 81.32%, a decrease in water bodies from 0.352% to 0.178%, and a decrease in open land from 2.124% to 1.134%, whereas grassland increased from 11.43% to 17.37% between 1990 and 2021. The landscape fragmentation in the edge density, contagion (CONTAG), largest patch index (LPI), number of patches (NP), and patch density (PD) was reduced in 2011 but increased again from 2016 to 2021, when only the ED fragmentation continued to decrease. The MANOVA results show that the rural population had a significant impact on LCLU changes at the 5% level of significance. Demographic factors significantly contributed to changes in grassland and forestland at a probability of 5%. In addition, moderately significant connections were observed between population growth per year and water and between gross domestic product (GDP) and grassland at the 10% level. ECO issues in ecosystem services (ECSs) were statistically significant for the increased fragmentation metrics, while biodiversity and habitat (BDH) were important for reducing the edge density (ED) at a 5% level of significance. The Pearson correlations showed a substantial positive relationship between the socioeconomic and demographic components, whereas a negative connection was found between the forestland and BDH indicators. These findings are essential for understanding the significant drivers of LCLU changes and the influence of environmental performance on the landscape pattern. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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36. Sex-specific differences in risk factors, comorbidities, diagnostic challenges, optimal management, and prognostic outcomes of heart failure with preserved ejection fraction: A comprehensive literature review.
- Author
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Abubakar, Muhammad, Saleem, Ayesha, Hajjaj, Mohsin, Faiz, Haseeb, Pragya, Aastha, Jamil, Rosheen, Salim, Siffat Saima, Lateef, Ibrahim Khaleel, Singla, Deepak, Ramar, Rajasekar, Damara, Ivan, and Shahid, Laraib
- Subjects
LITERATURE reviews ,VENTRICULAR ejection fraction ,HEART failure ,COMORBIDITY ,SYMPTOMS ,LUTEINIZING hormone releasing hormone - Abstract
Due to hormonal variations, heart failure with preserved ejection fraction (HFpEF) remains prevalent in women and affects almost half of the heart failure (HF) patients. Given the yearly death rate of 10–30% and the unavailability of medications targeting HFpEF, the need arises for a better understanding of the fundamental mechanisms of this syndrome. This comprehensive review explores sex-specific differences in traditional risk factors; female-specific factors that may impact HFpEF development and response to therapy, including variations in hormone levels that may occur pre- and post-menopausal or during pregnancy; and disparities in comorbidities, clinical presentation, and diagnostic challenges. Lastly, the review addresses prognostic outcomes, noting that women with HFpEF have a poor quality of life but a higher survival rate. It also discusses novel biomarkers and precision medicine, emphasizing their potential to improve early detection and personalized treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
37. Insights into lithium manganese oxide–water interfaces using machine learning potentials.
- Author
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Eckhoff, Marco and Behler, Jörg
- Subjects
LITHIUM manganese oxide ,MACHINE learning ,FORCE & energy ,OXYGEN evolution reactions ,MANGANESE ,LIQUID-vapor interfaces ,MANGANESE catalysts ,SOLID state batteries - Abstract
Unraveling the atomistic and the electronic structure of solid–liquid interfaces is the key to the design of new materials for many important applications, from heterogeneous catalysis to battery technology. Density functional theory (DFT) calculations can, in principle, provide a reliable description of such interfaces, but the high computational costs severely restrict the accessible time and length scales. Here, we report machine learning-driven simulations of various interfaces between water and lithium manganese oxide (Li
x Mn2 O4 ), an important electrode material in lithium ion batteries and a catalyst for the oxygen evolution reaction. We employ a high-dimensional neural network potential to compute the energies and forces several orders of magnitude faster than DFT without loss in accuracy. In addition, a high-dimensional neural network for spin prediction is utilized to analyze the electronic structure of the manganese ions. Combining these methods, a series of interfaces is investigated by large-scale molecular dynamics. The simulations allow us to gain insights into a variety of properties, such as the dissociation of water molecules, proton transfer processes, and hydrogen bonds, as well as the geometric and electronic structure of the solid surfaces, including the manganese oxidation state distribution, Jahn–Teller distortions, and electron hopping. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
38. Rapid, label-free classification of glioblastoma differentiation status combining confocal Raman spectroscopy and machine learning.
- Author
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Wurm, Lennard M., Fischer, Björn, Neuschmelting, Volker, Reinecke, David, Fischer, Igor, Croner, Roland S., Goldbrunner, Roland, Hacker, Michael C., Dybaś, Jakub, and Kahlert, Ulf D.
- Subjects
MACHINE learning ,GLIOBLASTOMA multiforme ,TECHNOLOGICAL innovations ,PROTEIN structure ,STEM cells ,RAMAN spectroscopy - Abstract
Label-free identification of tumor cells using spectroscopic assays has emerged as a technological innovation with a proven ability for rapid implementation in clinical care. Machine learning facilitates the optimization of processing and interpretation of extensive data, such as various spectroscopy data obtained from surgical samples. The here-described preclinical work investigates the potential of machine learning algorithms combining confocal Raman spectroscopy to distinguish non-differentiated glioblastoma cells and their respective isogenic differentiated phenotype by means of confocal ultra-rapid measurements. For this purpose, we measured and correlated modalities of 1146 intracellular single-point measurements and sustainingly clustered cell components to predict tumor stem cell existence. By further narrowing a few selected peaks, we found indicative evidence that using our computational imaging technology is a powerful approach to detect tumor stem cells in vitro with an accuracy of 91.7% in distinct cell compartments, mainly because of greater lipid content and putative different protein structures. We also demonstrate that the presented technology can overcome intra- and intertumoral cellular heterogeneity of our disease models, verifying the elevated physiological relevance of our applied disease modeling technology despite intracellular noise limitations for future translational evaluation. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
39. Maternal diet quality and associations with plasma lipid profiles and pregnancy-related cardiometabolic health.
- Author
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van der Pligt, Paige F., Kuswara, Konsita, McNaughton, Sarah A., Abbott, Gavin, Islam, Sheikh Mohammed Shariful, Huynh, Kevin, Meikle, Peter J., Mousa, Aya, and Ellery, Stacey J.
- Subjects
CARDIOVASCULAR disease prevention ,MOTHERS ,CARDIOVASCULAR diseases risk factors ,BLOOD pressure ,WEIGHT gain in pregnancy ,TRIGLYCERIDES ,BIOMARKERS ,MULTIPLE regression analysis ,NUTRITIONAL requirements ,DIET ,GESTATIONAL age ,BLOOD collection ,RISK assessment ,COMPARATIVE studies ,DESCRIPTIVE statistics ,HEALTH behavior ,RESEARCH funding ,FOOD quality ,GESTATIONAL diabetes ,BODY mass index ,LIPIDS ,PREGNANCY - Abstract
Purpose: To assess the relationship of early pregnancy maternal diet quality (DQ) with maternal plasma lipids and indicators of cardiometabolic health, including blood pressure (BP), gestational diabetes mellitus (GDM) and gestational weight gain (GWG). Methods: Women (n = 215) aged 18–40 years with singleton pregnancies were recruited at 10–20 weeks gestation. Diet quality was assessed by the Dietary Guideline Index, calculated at early ([mean ± SD]) (15 ± 3 weeks) and late (35 ± 2 weeks) pregnancy. Lipidomic analysis was performed, and 698 species across 37 lipid classes were measured from plasma blood samples collected at early (15 ± 3 weeks) and mid (27 ± 3 weeks)-pregnancy. Clinical measures (BP, GDM diagnosis, weight) and blood samples were collected across pregnancy. Multiple linear and logistic regression models assessed associations of early pregnancy DQ with plasma lipids at early and mid-pregnancy, BP at three antenatal visits, GDM diagnosis and total GWG. Results: Maternal DQ scores ([mean ± SD]) decreased significantly from early (70.7 ± 11.4) to late pregnancy (66.5 ± 12.6) (p < 0.0005). At a false discovery rate of 0.2, early pregnancy DQ was significantly associated with 13 plasma lipids at mid-pregnancy, including negative associations with six triglycerides (TGs); TG(54:0)[NL-18:0] (neutral loss), TG(50:1)[NL-14:0], TG(48:0)[NL-18:0], TG(52:1)[NL-18:0], TG(54:1)[NL-18:1], TG(50:0)[NL-18:0]. No statistically significant associations were found between early pregnancy DQ and BP, GDM or GWG. Conclusion: Maternal diet did not adhere to Australian Dietary Guidelines. Diet quality was inversely associated with multiple plasma TGs. This study provides novel insights into the relationship between DQ, lipid biomarkers and cardiometabolic health during pregnancy. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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40. Are Overweight and Obesity Risk Factors for Developing Metabolic Syndrome or Hypertension after a Preeclamptic Event?
- Author
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Pizano-Zarate, Maria Luisa, Torres-Ramos, Yessica Dorin, Morales-Hernandez, Rosa Maria, Ramirez-Gonzalez, Maria Cristina, and Hernandez-Trejo, Maria
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OBESITY complications ,HYPERTENSION risk factors ,METABOLIC syndrome risk factors ,STATISTICS ,TRIGLYCERIDES ,PREECLAMPSIA ,RISK assessment ,PEARSON correlation (Statistics) ,PUERPERIUM ,RESEARCH funding ,DESCRIPTIVE statistics ,ODDS ratio ,DATA analysis software ,BODY mass index - Abstract
Objective: To identify the determinants and risks associated with developing hypertension and metabolic syndrome in the first year postpartum in women who experienced preeclampsia. Methods: A cohort study was conducted, involving women who had experienced preeclampsia (PE) recently. The control group was women with the same characteristics but a healthy pregnancy. The variables analyzed were somatometry, disease history, pre-pregnancy body mass index (Pre-BMI), and Third Adult Treatment Panel updated (ATP III) metabolic syndrome (MS) data (blood pressure, obesity, triglycerides, high-density lipoproteins, and fasting glucose). These variables were measured at 3, 6, and 12 months postpartum. Results: Women with a history of PE exhibited higher systolic and diastolic blood pressure than women without PE. The risk of developing isolated diastolic arterial hypertension at 3 and 12 months of follow-up was two to eight times greater in women with a history of PE. Factors associated with having higher blood pressure levels were preeclampsia, insulin resistance, age, and BMI. Neither the pre-BMI index nor gestational weight gain (GWG) had any effect on blood pressure in any of the three assessments. Women with preeclampsia had a 5- to 8-fold increased risk of developing MS (which could be explained not only by the history of preeclampsia but also by the history of pre-pregnancy obesity). However, PE was not identified as a risk factor at the six-month evaluation and was only explained by pre-pregnancy obesity and overweight. Conclusions: Obesity and overweight, as well as preeclampsia, were strongly associated with the development of hypertension and metabolic syndrome during the first year following childbirth. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
41. Preparation and supercapacitive performance of CuFe2O4 hollow-spherical nanoparticles.
- Author
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Zhang, Yu, Zhu, Qingguang, Zhao, Yaqi, Yang, Xin, and Jiang, Ling
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SUPERCAPACITOR electrodes ,ENERGY storage ,SUPERCAPACITOR performance ,NANOPARTICLES ,ETHYLENE glycol - Abstract
Spinel-type CuFe
2 O4 nanoparticles were synthesized by a solvothermal method using ethylene glycol as solvent and polyvinylpyrrolidone (PVP) as dispersant. The characterization results showed that the average diameter of the hollow-spherical CuFe2 O4 was approximately 100 nm with homogeneous morphology and negligible agglomeration. CuFe2 O4 was used as the active electrode material to explore its supercapacitive properties in different concentrations of KOH electrolytes. It was found that the CuFe2 O4 hollow-spherical nanoparticles exhibit potential electronic performance in supercapacitor, with a specific capacitance of 368.2 F/g and capacitance stability retention of 91.0% after 2000 cycles at the current density of 5 A/g in 3 mol/L KOH electrolyte. The present findings demonstrate that the CuFe2 O4 electrode materials can have important implications with practical prospects in energy storage systems. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
42. Profile and Prognostic Impact of Multimorbidity in Elderly Patients with Heart Failure: Are there Differences between Men and Women?
- Author
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Del Pilar Falcón Fleytas R, Centurión OA, Figueredo JG, Saldivar HG, and Martínez JE
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- Humans, Prognosis, Female, Aged, Male, Sex Factors, Quality of Life, Age Factors, Heart Failure epidemiology, Heart Failure mortality, Multimorbidity
- Abstract
Purpose of Review: Heart failure (HF) represents a pathology in constant growth, but, despite the fact that a significant proportion of its population is comprised of elderly patients, they are not adequately represented in clinical trials or registries. They constitute a heterogeneous population with their particularities and interaction of the multiple comorbidities that characterize this age group, which makes the clinical course, prognosis and outcomes of the disease different., Recent Findings: Compared to men, women with HF tend to be older, with a greater burden of non-cardiovascular comorbidities, less ischemic heart disease and preserved ventricular function in most cases. This fact translates into worse self-perceived quality of life, with lower hospitalization and mortality rates. Moreover, paradoxically, women are less likely to receive treatment recommended by clinical practice guidelines, including revascularization and device placement. As there are not enough representative studies of this population, the reasons for these results with better prognosis and relatively benign impact in the elderly female population are unknown, which is why it is necessary to continue with research in order to obtain greater evidence of the exposed gaps., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2024
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43. Differences in presentation, diagnosis and management of heart failure in women. A scientific statement of the Heart Failure Association of the ESC.
- Author
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Rosano GMC, Stolfo D, Anderson L, Abdelhamid M, Adamo M, Bauersachs J, Bayes-Genis A, Böhm M, Chioncel O, Filippatos G, Hill L, Lainscak M, Lambrinou E, Maas AHEM, Massouh AR, Moura B, Petrie MC, Rakisheva A, Ray R, Savarese G, Skouri H, Van Linthout S, Vitale C, Volterrani M, Metra M, and Coats AJS
- Subjects
- Female, Humans, Disease Management, Prognosis, Sex Factors, Societies, Medical, Heart Failure therapy, Heart Failure diagnosis
- Abstract
Despite the progress in the care of individuals with heart failure (HF), important sex disparities in knowledge and management remain, covering all the aspects of the syndrome, from aetiology and pathophysiology to treatment. Important distinctions in phenotypic presentation are widely known, but the mechanisms behind these differences are only partially defined. The impact of sex-specific conditions in the predisposition to HF has gained progressive interest in the HF community. Under-recruitment of women in large randomized clinical trials has continued in the more recent studies despite epidemiological data no longer reporting any substantial difference in the lifetime risk and prognosis between sexes. Target dose of medications and criteria for device eligibility are derived from studies with a large predominance of men, whereas specific information in women is lacking. The present scientific statement encompasses the whole scenario of available evidence on sex-disparities in HF and aims to define the most challenging and urgent residual gaps in the evidence for the scientific and clinical HF communities., (© 2024 European Society of Cardiology.)
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- 2024
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44. Lack of social support, gender and colorectal cancer screening participation across Europe: How do screening programmes mitigate the effect of social support for men and women?
- Author
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Jolidon V, De Prez V, Bracke P, Cullati S, and Burton-Jeangros C
- Subjects
- Humans, Male, Female, Europe, Middle Aged, Aged, Sex Factors, Mass Screening psychology, Patient Acceptance of Health Care psychology, Colorectal Neoplasms diagnosis, Colorectal Neoplasms prevention & control, Social Support, Early Detection of Cancer psychology
- Abstract
This study investigates how a lack of social support differentially affects men and women's colorectal cancer (CRC) screening participation, considering different screening strategies implemented across European countries. Although health sociology has stressed gender differences in social support and its effects on health behaviours, this was overlooked by cancer screening research. Using a data set of 65,961 women and 55,602 men in 31 European countries, we analysed the effect of social support variables on CRC screening uptake. We found that living alone and lower perceived social support were associated with lower screening uptake for both men and women. These effects were, however, stronger among men. Population-based screening programmes mitigated these effects, particularly for women, but not for men living alone. In countries with opportunistic screening programmes, social support variables remained associated with screening uptake. We conclude that cancer screening interventions should pay attention to social support and its gender-differentiated effects., (© 2024 The Authors. Sociology of Health & Illness published by John Wiley & Sons Ltd on behalf of Foundation for the Sociology of Health & Illness.)
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- 2024
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45. miRNA and mRNA expression signatures in a HFpEF large animal model.
- Author
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Chen, Yang and Seale, Patrick
- Subjects
GENE expression ,ATRIAL natriuretic peptides ,SMALL interfering RNA ,TREADMILL exercise tests ,HUMAN biology ,HEART failure ,GLUCAGON-like peptide-1 agonists ,TRANSCRIPTION factors - Abstract
The article discusses the development of a large animal model for heart failure with preserved ejection fraction (HFpEF) using castrated male pigs. The study identified microRNA (miRNA) and messenger RNA (mRNA) signatures associated with HFpEF, highlighting potential molecular targets for future therapeutic investigations. The authors emphasize the importance of including female pigs in future studies to account for sex differences in HFpEF pathophysiology and suggest exploring the function of identified targets in human cells or genetic mouse models for validation. Additionally, the article underscores the significance of large animal models in drug discovery for cardiovascular diseases like HFpEF, bridging the gap between rodent studies and human clinical trials. [Extracted from the article]
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- 2024
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46. Electrocatalytic Mechanism of Defect in Spinels for Water and Organics Oxidation.
- Author
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Liu, Zhijuan, Kong, Zhijie, Cui, Shasha, Liu, Luyu, Wang, Fen, Wang, Yanyong, Wang, Shuangyin, and Zang, Shuang‐quan
- Published
- 2023
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47. Prevention of Cardiovascular Disease in Women With Pregnancy-Related Risk Factors: A Prospective Women's Heart Clinic Study.
- Author
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Marschner, Simone, Mukherjee, Swati, Watts, Monique, Haeri Min, Beale, Anna L., O'Brien, Jessica, Juneja, Aashima, Tremmel, Jennifer A., and Zaman, Sarah
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- 2023
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48. Wavelet and Earth Mover's Distance Coupling Denoising Techniques.
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Zhang, Zhihua, Xu, Xudong, and Crabbe, M. James C.
- Subjects
IMAGE denoising ,EUCLIDEAN distance ,STORAGE & moving industry ,SPATIAL filters - Abstract
The widely used wavelet-thresholding techniques (DWT-H and DWT-S) have a near-optimal behavior that cannot be enhanced by any local denoising filter, but they cannot utilize the similarity of small-size image patches to enhance the denoising performance. Two of the latest improvements (WNLM and NLMW) introduced the Euclidean distance to measure the similarity of image patches, and then used the non-local meaning of similar patches for further denoising. Since the Euclidean distance is not a good similarity measurement, these two improvements are limited. In this study, we introduced the earth mover's distance (EMD) as the similarity measure of small-scale patches within the wavelet sub-bands of noisy images. Moreover, at higher noise levels, we further incorporated joint bilateral filtering, which can filter both the spatial domain and the intensity domain of images. Denoising simulation experiments on BSDS500 demonstrated that our algorithm outperformed the DWT-H, DWT-S, WNLM, and NLMW algorithms by 4.197 dB, 3.326 dB, 2.097 dB, and 1.162 dB in terms of the average PSNR, and by 0.230, 0.213, 0.132, and 0.085 in terms of the average SSIM. [ABSTRACT FROM AUTHOR]
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- 2023
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49. An environmental habitat gradient and within-habitat segregation enable co-existence of ecologically similar bird species.
- Author
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Ayebare, Samuel, Doser, Jeffrey W., Plumptre, Andrew J., Owiunji, Isaiah, Mugabe, Hamlet, and Zipkin, Elise F.
- Subjects
HABITAT partitioning (Ecology) ,COEXISTENCE of species ,ENVIRONMENTAL indicators ,MOUNTAIN forests ,ECOLOGICAL niche ,HABITATS - Abstract
Niche theory predicts that ecologically similar species can coexist through multidimensional niche partitioning. However, owing to the challenges of accounting for both abiotic and biotic processes in ecological niche modelling, the underlying mechanisms that facilitate coexistence of competing species are poorly understood. In this study, we evaluated potential mechanisms underlying the coexistence of ecologically similar bird species in a biodiversity-rich transboundary montane forest in east-central Africa by computing niche overlap indices along an environmental elevation gradient, diet, forest strata, activity patterns and within-habitat segregation across horizontal space. We found strong support for abiotic environmental habitat niche partitioning, with 55% of species pairs having separate elevation niches. For the remaining species pairs that exhibited similar elevation niches, we found that within-habitat segregation across horizontal space and to a lesser extent vertical forest strata provided the most likely mechanisms of species coexistence. Coexistence of ecologically similar species within a highly diverse montane forest was determined primarily by abiotic factors (e.g. environmental elevation gradient) that characterize the Grinnellian niche and secondarily by biotic factors (e.g. vertical and horizontal segregation within habitats) that describe the Eltonian niche. Thus, partitioning across multiple levels of spatial organization is a key mechanism of coexistence in diverse communities. [ABSTRACT FROM AUTHOR]
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- 2023
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50. Nano‐enabled Quenching of Bacterial Communications for the Prevention of Biofilm Formation.
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Gao, Meng, Xu, Bolong, Huang, Yang, Cao, Jiayu, Yang, Lili, Liu, Xi, Djumaev, Alisher, Wu, Di, Shoxiddinova, Moxichexra, Cai, Xiaoming, Tojiyev, Behruz, Zheng, Huizhen, Li, Xuehua, Normurodova, Kunduz, Liu, Huiyu, and Li, Ruibin
- Subjects
ACYL-homoserine lactones ,DRUG resistance in bacteria ,BIOFILMS ,BACTERIAL enzymes ,QUORUM sensing ,DRUG resistance in microorganisms ,ANTIFOULING paint - Abstract
Biofilm formation is a major threat to industry, the environment and human health. While killing of embedded microbes in biofilms may inevitably lead to the evolution of antimicrobial resistance (AMR), catalytic quenching of bacterial communications by lactonase is a promising antifouling approach. Given the shortcomings of protein enzymes, it is attractive to engineer synthetic materials to mimic the activity of lactonase. Herein, an efficient lactonase‐like Zn−Nx−C nanomaterial was synthesized by tuning the coordination environment around zinc atoms to mimic the active domain of lactonase for catalytical interception of bacterial communications in biofilm formation. The Zn−Nx−C material could selectively catalyze 77.5 % hydrolysis of N‐acylated‐L‐homoserine lactone (AHL), a critical bacterial quorum sensing (QS) signal in biofilm construction. Consequently, AHL degradation downregulated the expression of QS‐related genes in antibiotic resistant bacteria and significantly prevented biofilm formation. As a proof of concept, Zn−Nx−C‐coated iron plates prevented 80.3 % biofouling after a month exposure in river. Overall, our study provides a nano‐enabled contactless antifouling insight to avoid AMR evolution by engineering nanomaterials for mimicking the key bacterial enzymes (e.g. lactonase) functioning in biofilm construction. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
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