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Physical Chemistry Chemical Physics :... Jul 2024The radiative cooling of naphthalene dimer cations, (CH) was studied experimentally through action spectroscopy using two different electrostatic ion-beam storage rings,...
The radiative cooling of naphthalene dimer cations, (CH) was studied experimentally through action spectroscopy using two different electrostatic ion-beam storage rings, DESIREE in Stockholm and Mini-Ring in Lyon. The spectral characteristics of the charge resonance (CR) band were observed to vary significantly with a storage time of up to 30 seconds in DESIREE. In particular, the position of the CR band shifts to the blue, with specific times (inverse of rates) of 0.64 s and 8.0 s in the 0-5 s and 5-30 s storage time ranges, respectively. These long-time scales indicate that the internal energy distribution of the stored ions evolves by vibrational radiative cooling, which is consistent with the absence of fast radiative cooling recurrent fluorescence for (CH). Density functional based tight binding calculations with local excitations and configuration interactions (DFTB-EXCI) were used to simulate the absorption spectrum for ion temperatures between 10 and 500 K. The evolution of the bandwidth and position with temperature is in qualitative agreement with the experimental findings. Furthermore, these calculations yielded linear temperature dependencies for both the shift and the broadening. Combining the relationship between the CR band position and the ion temperature with the results of the statistical model, we demonstrate that the observed blue shift can be used to determine the radiative cooling rate of (CH).
PubMed: 38949429
DOI: 10.1039/d4cp01200c -
International Journal of Chronic... 2024Vitamin D deficiency (VDD, 25-hydroxyvitamin D < 20 ng/mL) has been reported associated with exacerbation of chronic obstructive pulmonary disease (COPD) but sometimes... (Observational Study)
Observational Study
PURPOSE
Vitamin D deficiency (VDD, 25-hydroxyvitamin D < 20 ng/mL) has been reported associated with exacerbation of chronic obstructive pulmonary disease (COPD) but sometimes controversial. Research on severe vitamin D deficiency (SVDD, 25-hydroxyvitamin D < 10 ng/mL) in exacerbation of COPD is limited.
PATIENTS AND METHODS
We performed a retrospective observational study in 134 hospitalized exacerbated COPD patients. 25-hydroxyvitamin D was modeled as a continuous or dichotomized (cutoff value: 10 or 20 ng/mL) variable to evaluate the association of SVDD with hospitalization in the previous year. Receiver operator characteristic (ROC) analysis was performed to find the optimal cut-off value of 25-hydroxyvitamin D.
RESULTS
In total 23% of the patients had SVDD. SVDD was more prevalent in women, and SVDD group tended to have lower blood eosinophils counts. 25-hydroxyvitamin D level was significantly lower in patients who were hospitalized in the previous year (13.6 vs 16.7 ng/mL, = 0.044), and the prevalence of SVDD was higher (38.0% vs 14.3%, = 0.002). SVDD was independently associated with hospitalization in the previous year [odds ratio (OR) 4.34, 95% CI 1.61-11.72, = 0.004] in hospitalized exacerbated COPD patients, whereas continuous 25-hydroxyvitamin D and VDD were not ( = 0.1, = 0.9, separately). The ROC curve yielded an area under the curve of 0.60 (95% CI 0.50-0.71) with an optimal 25-hydroxyvitamin D cutoff of 10.4 ng/mL.
CONCLUSION
SVDD probably showed a more stable association with hospitalization in the previous year in hospitalized exacerbated COPD patients. Reasons for lower eosinophil counts in SVDD group needed further exploration.
Topics: Humans; Pulmonary Disease, Chronic Obstructive; Vitamin D Deficiency; Female; Male; Retrospective Studies; Vitamin D; Aged; Prevalence; Disease Progression; Risk Factors; Middle Aged; Severity of Illness Index; Biomarkers; ROC Curve; Hospitalization; Time Factors; Odds Ratio; Aged, 80 and over; Area Under Curve; Logistic Models; Chi-Square Distribution; Patient Admission; Multivariate Analysis
PubMed: 38948911
DOI: 10.2147/COPD.S461029 -
Journal of Family Medicine and Primary... May 2024Since beginning of the coronavirus disease (COVID-19) it became clear that severe forms of this infection have primarily affected patients with chronic conditions.
Clinical and epidemiological risk factors associated with hospitalization and mortality rate of COVID-19 patients in Banja Luka County: A retrospective observational cohort study on 40,000 patients.
CONTEXT
Since beginning of the coronavirus disease (COVID-19) it became clear that severe forms of this infection have primarily affected patients with chronic conditions.
AIMS
The aim of the study was to explore clinical and epidemiological characteristics associated with COVID 19 outcomes.
SETTINGS AND DESIGN
The retrospective observational study included 40,692 citizens of Banja Luka County, Bosnia and Herzegovina, who were confirmed as reverse transcriptase polymerase chain reaction (RT-PCR) positive on COVID-19 at a primary healthcare centre from March 2020 to September 2022.
METHODS AND MATERIALS
Epidemiological data were obtained from Web-Medic medical records of patients. The COVID-19 data were obtained from COVID-19 data sheets comprised of patients' RT-PCR testing forms, surveillance forms for severe acute respiratory syndrome coronavirus-2 status, and a map of their positive and isolated contacts.
STATISTICAL ANALYSIS USED
Differences regarding the distributions of patients between groups were analysed using the Pearson chi-square test and Mantel-Haenszel chi-square test for trends, while differences in mean values were compared using an independent sample -test.
RESULTS
The average age of hospitalised patients was significantly higher compared to the age of non-hospitalised patients ( < 0.001). The average age of patients with lethal outcomes was nearly twice as high in comparison to patients with non-lethal outcomes ( < 0.001). Male patients had a higher hospitalization and mortality rate ( < 0.001). The highest hospitalization rate was in patients with chronic renal failure (CRF), diabetes and cardiovascular diseases (CVDs), while the death rate was the highest among patients with CRF and hearth comorbidities. Patients with fatigue and appetite loss had a higher percentage of lethal outcomes. Vaccinated patients had a significantly lower rate of lethal outcome.
CONCLUSIONS
Clinical symptoms, signs and outcomes, are posing as predictive parameters for further management of COVID-19. Vaccination has an important role in the clinical outcomes of COVID-19.
PubMed: 38948596
DOI: 10.4103/jfmpc.jfmpc_1641_23 -
Imaging Science in Dentistry Jun 2024Preoperative identification of the intraosseous posterior superior alveolar artery (PSAA) is critical when planning sinus surgery. This study was conducted to determine...
PURPOSE
Preoperative identification of the intraosseous posterior superior alveolar artery (PSAA) is critical when planning sinus surgery. This study was conducted to determine the distance between the cementoenamel junction and the PSAA, as well as to identify factors influencing the detection of the PSAA on cone-beam computed tomography (CBCT).
MATERIALS AND METHODS
In total, 254 CBCT scans of maxillary sinuses, acquired with 2 different scanners, were examined to identify the PSAA. The distance from the cementoenamel junction (CEJ) to the PSAA was recorded at each maxillary posterior tooth position. Binomial logistic regression and multiple linear regression were employed to evaluate the effects of scanner type, CBCT parameters, sex, and age on PSAA detection and CEJ-PSAA distance, respectively. -values less than 0.05 were considered to indicate statistical significance.
RESULTS
The mean CEJ-PSAA distances at the second molar, first molar, second premolar, and first premolar positions were 17.0±4.0 mm, 21.8±4.1 mm, 19.5±4.7 mm, and 19.9±4.9 mm for scanner 1, respectively, and 17.3±3.5 mm, 16.9±4.3 mm, 18.5±4.1 mm, and 18.4±4.3 mm for scanner 2. No independent variable significantly influenced PSAA detection. However, tooth position (b=-0.67, <0.05) and scanner type (b=-1.3, <0.05) were significant predictors of CEJ-PSAA distance.
CONCLUSION
CBCT-based estimates of CEJ-PSAA distance were comparable to those obtained in previous studies involving cadavers, CT, and CBCT. The type of CBCT scanner may slightly influence this measurement. No independent variable significantly impacted PSAA detection.
PubMed: 38948184
DOI: 10.5624/isd.20230160 -
Molecular Ecology Jul 2024The Cenozoic topographic development of the Himalaya-Tibet orogen (HTO) substantially affected the paleoenvironment and biodiversity patterns of High Asia. However,...
The Cenozoic topographic development of the Himalaya-Tibet orogen (HTO) substantially affected the paleoenvironment and biodiversity patterns of High Asia. However, concepts on the evolution and paleoenvironmental history of the HTO differ massively in timing, elevational increase and sequence of surface uplift of the different elements of the orogen. Using target enrichment of a large set of transcriptome-derived markers, ancestral range estimation and paleoclimatic niche modelling, we assess a recently proposed concept of a warm temperate paleo-Tibet in Asian spiny frogs of the tribe Paini and reconstruct their historical biogeography. That concept was previously developed in invertebrates. Because of their early evolutionary origin, low dispersal capacity, high degree of local endemism, and strict dependence on temperature and humidity, the cladogenesis of spiny frogs may echo the evolution of the HTO paleoenvironment. We show that diversification of main lineages occurred during the early to Mid-Miocene, while the evolution of alpine taxa started during the late Miocene/early Pliocene. Our distribution and niche modelling results indicate range shifts and niche stability that may explain the modern disjunct distributions of spiny frogs. They probably maintained their (sub)tropical or (warm)temperate preferences and moved out of the ancestral paleo-Tibetan area into the Himalaya as the climate shifted, as opposed to adapting in situ. Based on ancestral range estimation, we assume the existence of low-elevation, climatically suitable corridors across paleo-Tibet during the Miocene along the Kunlun, Qiangtang and/or Gangdese Shan. Our results contribute to a deeper understanding of the mechanisms and processes of faunal evolution in the HTO.
PubMed: 38946613
DOI: 10.1111/mec.17446 -
Journal of Indian Prosthodontic Society Jul 2024Studies have not been done to evaluate the peri-implant stress exerted by materials(like PEEK and resin matrix ceramics) in different osseointegration conditions. To...
AIM
Studies have not been done to evaluate the peri-implant stress exerted by materials(like PEEK and resin matrix ceramics) in different osseointegration conditions. To investigate the effect of different occlusal materials on peri-implant stress distribution with different osseointegration condition using finite element analysis.
SETTINGS AND DESIGN
Eighteen different 3D FEA models of implant fixed with abutment were created involving 6 different occlusal materials (Heat cured temporary acrylic resin (PMMA), Bis-GMA, PEEK, Lithium disilicate, Resin matrix ceramics and translucent Zirconia) and different osseointegrated conditions (50%, 75%, 100%).
MATERIALS AND METHODS
Models were subjected to loading vertically and obliquely followed by evaluation of stress distribution.
STATISTICAL ANALYSIS USED
The results of the simulation obtained were analysed in terms of Von mises, maximum principal and minimal principal stresses using descriptive stastistics.
RESULTS
PMMA (40.14 MPa on vertical loading and 66 MPa on oblique loading) resulted in the highest stresses and lithium disilicate (24 MPa on vertical loading and 52.40 MPa on oblique loading) resulted in least stresses among all the crown materials. Upon oblique loading, von Mises stress increases except for translucent zirconia and lithium disilicate (52.444 MPa on 50%, 47.733 MPa on 75%, and 43.973 MPa on 100% osseointegration). Minimal principal stress values decreased with increase in osseointegration upon oblique loading for PMMA, BisGMA, and PEEK.
CONCLUSION
Translucent zirconia and lithium disilicate offer a better stress transmission. Minimal principal stress values of PEEK and BisGMA decreased with increasing osseointegration.
Topics: Finite Element Analysis; Osseointegration; Dental Materials; Dental Implants; Zirconium; Humans; Dental Porcelain; Ceramics; Materials Testing; Stress, Mechanical; Dental Stress Analysis; Polymethyl Methacrylate; Polymers
PubMed: 38946514
DOI: 10.4103/jips.jips_424_23 -
Journal of Indian Prosthodontic Society Jul 2024The aim of this study is to evaluate the influence of occlusion on body posture and plantar arch pressure. (Observational Study)
Observational Study
AIM
The aim of this study is to evaluate the influence of occlusion on body posture and plantar arch pressure.
SETTINGS AND DESIGN
An Observational analysis to Analyze the Influence of Occlusion on Plantar Pressure and Body Posture.
MATERIALS AND METHODS
A total of 30 asymptomatic subjects were selected for the study including 18 females and 12 males from age group 22 years to 28 years with a mean age of 24.83 years. Each subject underwent evaluation of occlusion at MIP using a Digital Occlusal analyzer (T-Scan III). At this point, the subjects were made to stand on a mat scan which consisted of a large postural platform sensor and a computer that displayed the plantar pressure data. The computer connected to the T Scan displayed the occlusal pressure analysis. This was followed by an evaluation of body posture using a posture grid where the photographs were taken and an evaluation of the frontal and lateral photos was done using the APECS - posture analysis app.
STATISTICAL ANALYSIS USED
Statistical package for social sciences (SPSS) for windows version 22.0 Released 2013, Armonk, N Y: IBM Corp., was used to perform Statistical Analysis. A chi-square test was applied for qualitative variables to find the association. Paired t-test was applied to compare the changes in the quantitative parameters in eye-open and eye-closed conditions. The level of significance was set at 5%.
RESULTS
As observed from the results, occlusion for 40% of the subjects, where n = 12, was dominant on the right side. Occlusion for 23.3% of subjects, where n = 7, was dominant on the left side. Whereas, for 36.7% of subjects, where n = 11, the pressure distribution was almost equal on both sides. The inclination of body posture for 23.3% of subjects, where n = 7, was towards the right side. The inclination of body posture for 50% of subjects, where n = 11, was towards the left side. And, the inclination of body posture for 26.7% of subjects, where n = 8, was neutral i.e., balanced on the right and left side. Plantar pressure for 6.7% of subjects, where n = 2, was dominant on the right side. Plantar pressure for 36.7% of subjects, where n = 11, was dominant on the left side. Whereas, for 56.7% of subjects, where n = 17, the plantar pressure distribution was almost equal on both sides.
CONCLUSION
On correlating the three parameters, it was found that occlusion for most of the subjects dominated on the right side, while body posture and plantar pressure dominated on the contralateral i.e., left side.
Topics: Humans; Male; Female; Posture; Adult; Pressure; Young Adult; Foot; Dental Occlusion
PubMed: 38946511
DOI: 10.4103/jips.jips_497_23 -
Journal of Indian Prosthodontic Society Jul 2024Assessment of occlusion changes during laboratory phase of relining is essential to evaluate the occlusal discrepancies that could get incorporated in the denture with...
AIM
Assessment of occlusion changes during laboratory phase of relining is essential to evaluate the occlusal discrepancies that could get incorporated in the denture with the use of different relining materials. Since the long term stability and functional success of the denture is heavily influenced by occlusion, an In-vitro study to assess these changes after relining is warranted. The aim of the study is to evaluate the changes in occlusion during laboratory phase of relining procedure.
SETTINGS AND DESIGN
This is an in vitro study with a total of 30 specimen.
MATERIALS AND METHODOLOGY
A total of 30 maxillary standardized dentures were fabricated after mounting on a semi adjustable articulator. These samples will be divided into three groups based on the relining material used (Autopolymerizing resin, Heat-cure resin, Tissue conditioner). The vertical dimension, Centric contact points and eccentric contact points were measured before and after relining.
STATISTICAL ANALYSIS USED
The variables were tested to see if they had a normal distribution using the Shapiro-Wilk test. Parametric distribution was seen for ECP leading to further comparison using one way analysis of variance (ANOVA). Non-parametric distribution was found while testing the VD, CCP leading to adoption of Kruskal-wallis test for comparison of groups. Dunn Bonferroni test was done for VD since results were significant.
RESULTS
The results of this in-vitro study showed statistically significant difference with respect to change in vertical dimension in all groups pre and post relining (P = 0.005). The centric contact points showed lesser variation in position when comparing the pre to the post relining phase with the use of autopolymerising resins, whereas heat cure resins and tissue conditioners showed statistically significant difference in the centric point contacts post relining. No statistically significant changes were seen in eccentric occlusion post relining in all groups. Tissue conditioners showed minimum mean changes in eccentric contacts.
CONCLUSION
Within the limitations of this study, the use of autopolymerising resins depicted the most stable results with respect to occlusion, for relining of dentures.
Topics: Humans; In Vitro Techniques; Dental Occlusion; Denture Retention; Dental Materials; Denture Liners
PubMed: 38946509
DOI: 10.4103/jips.jips_363_23 -
Dental Materials : Official Publication... Jun 2024This study investigated the influence of photoinitiator types on degree of conversion (DC), rate of polymerization (RP), flexural strength (FS), flexural modulus (FM),...
The effect of photoinitiator type and filler load on physicochemical and mechanical properties of experimental light-cured resin cements through lithium disilicate ceramics of different shades and thicknesses.
OBJECTIVE
This study investigated the influence of photoinitiator types on degree of conversion (DC), rate of polymerization (RP), flexural strength (FS), flexural modulus (FM), and light transmittance (LT) of filled and unfilled light-curable resin cements through different thicknesses and shades of lithium disilicate ceramics.
METHODS
Lithium disilicate ceramic discs (IPS Emax Press, background [0.0], 0.5, 1.0, 2.0, 3.0, and 4.0 mm, shades A1 and BL3) were prepared. Experimental resin-based cements [TEGDMA/BisGMA (50/50 mass%)] were prepared using either camphorquinone (CQ)/amine (0.44/1.85 mol%) or TPO (0.44 mol%)], and a micro and nanofiller loads of nil (unfilled); 40/10 mass%; and 50/10 mass%). Resin cements (0.2 mm thick) were placed on the lower surface of the ceramic specimens and light-activated for 30 s from the upper surface using a Bluephase Style curing light (exitance at tip: 1236 mW/cm ± 1.20). LT and distribution of irradiance through the ceramics were measured using a UV-vis spectrometer and a beam profile camera, respectively (n = 3). The DC and RP were measured in real-time using mid infrared spectroscopy in attenuated total reflectance (ATR) mode (n = 3). FS and FM were measured using a universal testing machine (n = 5). Statistical analyses were performed on LT, DC, RP, FS, and FM data using a general linear model, and supplementary ANOVA and post hoc Tukey multiple comparison test were also performed (α = .05).
RESULTS
Thicknesses, shades, photoinitiator type, and fillers load significantly influenced the optical and mechanical characteristics of the resin-based materials (p < 0.05). The BL3 shade ceramic provided higher values of DC, RP, FS, FM, and LT compared with the A1 shade (p < 0.05). Increasing ceramic thickness decreased the properties of the resin-based materials (p < 0.05). Generally, TPO improved mechanical properties of the resin cement compared with CQ (p < 0.05).
SIGNIFICANCE
The luting process of indirect restorations may be improved by using high molar absorptivity, more reactive, and more efficient photoinitiators such as TPO, as opposed to conventional CQ. The use of such initiator may allow the placement of thicker and more opaque indirect restorations.
PubMed: 38945741
DOI: 10.1016/j.dental.2024.06.020 -
The Science of the Total Environment Jun 2024Groundwater in karst regions is of immense value due to its vital support for regional ecosystems and residents' livelihoods. However, it is simultaneously threatened by...
Groundwater in karst regions is of immense value due to its vital support for regional ecosystems and residents' livelihoods. However, it is simultaneously threatened by multi-source pollution from agricultural non-point sources, industrial and domestic point sources, and mining activities. This study focuses on the Guangxi of China, which features typical karst topography, aiming to thoroughly assess the groundwater quality and related health risks in Guangxi, especially identifying the impacts of various key pollution sources on the groundwater environment. A total of 1912 groundwater samples were collected, covering an area of approximately 237,600 km. The spatial distribution of pollutants was analysed using the Nemeroww index method and Kriging interpolation, while multivariate statistical and cluster analysis methods were employed to identify the main types of pollution sources. Furthermore, based on the human health risk assessment model of the U.S. Environmental Protection Agency (US EPA), a risk assessment was conducted for key pollutants. The results revealed widespread heavy metal contamination in Guangxi's groundwater, particularly with concentrations of Mn, As, Al, Pb reaching up to 9.4 mg/L, 2.483 mg/L, 37.95 mg/L, 4.761 mg/L, respectively, significantly exceeding China's national Class III groundwater quality standards. Cluster analysis indicated that mining and industrial activities are the primary sources of pollution. The health risk assessment demonstrated that these activities pose a significant risk to public health. The aim of this study is to provide a scientific basis for the protection of the groundwater environment in Guangxi and other karst areas, the formulation of pollution prevention and control strategies, and the optimization of urban and industrial land use layouts. Future research should focus on advanced isotopic and molecular biological techniques to trace pollution sources more precisely and evaluate the effectiveness of pollution control measures.
PubMed: 38945232
DOI: 10.1016/j.scitotenv.2024.174371