74 research outputs found
Using a quench level approximation to estimate the effect of metallicity on N-bearing species abundances in H2-dominated atmospheres
Variations in atmospheric elemental nitrogen can considerably affect the
abundance of major nitrogen-bearing species such as NH and HCN. Also, due
to vertical mixing and photochemistry, their abundance deviates from the
thermochemical equilibrium. The goal of this study is to understand the effect
of atmospheric metallicity on the composition of NH, N, and HCN over a
large parameter space in the presence of vertical mixing which, when combined
with the work on CHO-bearing species in Soni and Acharyya (2023) can provide a
comprehensive understanding of the effect of atmospheric metallicity. We used
quenching approximations and a full chemical kinetics model for the
calculations, and a comparison between these two methods was made. For
generating thermal profiles, petitRADTRANS code is used. Chemical timescales of
NH and N are found to be complex functions of metallicity, while HCN is
inversely proportional. Using NH and CO quenched abundances, the HCN
quenched abundance can be constrained since it remains in equilibrium with
NH, CO, and HO. Quenched NH increases with increasing K
untill a particular point, after which it becomes independent of vertical
mixing. There is a sweet spot in the K parameter space to maximize the
quenched HCN for a given T and T; the parameter space moves
towards the lower equilibrium temperature, and HCN abundance increases with
metallicity. Finally, we used the dataset of quenched abundances to provide a
list of potential candidates in which HCN observation can be possible.Comment: 41 pages, 20 figures, 3 table, accepted for publication in the
Astrophysical Journa
The Effect of Metallicity on the Non-Equilibrium Abundance of Hydrogen Dominated Exoplanet Atmosphere
The atmospheric metallicity greatly influences the composition of exoplanet
atmospheres. The effect of metallicity on the thermochemical equilibrium is
well studied, though its effect on the disequilibrium abundance is loosely
constrained. In this study, we have used the quenching approximation to study
the effect of metallicity on the quenched abundance for a range of parameters
(temperature: 500-2500 K, pressure: 10-10 bar, metallicity: 0.1-1000
solar metallicity). We determine the chemical timescale by finding
rate limiting steps in a reduced chemical network with a network analysis tool
and the thermochemical equilibrium abundance. The equilibrium abundance results
are similar to the literature. The CO, HO, and CO abundances increase
with metallicity in the parameter range considered. The CH abundance
increases with metallicity for CO/CH 1 and is unaffected for CO/CH
1. The chemical timescale of CO shows minimal change with the metallicity,
while the CH chemical timescale is inversely proportional to atmospheric
metallicity. The quench level of CO shifts into the high-pressure region, and
the quench level of CH shows complex behavior with metallicity. We
benchmarked the quenching approximation with the 1D photochemistry-transport
model for two test exoplanets (GJ 1214 b and HD 189733 b) and found it to be in
good agreement. We also found that the quenching approximation is a powerful
tool to constrain atmospheric parameters. We demonstrated this by constraining
the metallicity and transport strength for the test exoplanets HR 8799 b, HD
189733 b, GJ 436 b, and WASP-39 b.Comment: 51 pages, 26 figures, 1 table, accepted for publication in the
Astrophysical Journa
Advances in Natural Polymeric Nanoparticles for the Drug Delivery
Natural and biodegradable polymers have been the key area for utilizing their advantages which make them a possible option for development of various drug delivery systems. The complexity of diseases and the intrinsic drug toxicity and side effects has led to an interest for development and optimization of drug delivery systems. The advancements in nanotechnology have favored the development of novel formulations which can modulate the biopharmaceutical properties of bioactives and thus improves the pharmacological and therapeutic action. The shape, size, and charge nanoscale delivery system, such as nanoparticles (NPs) are required to be investigated and changed in order to promote and optimize the formulations. The various natural polymeric NPs (PNPs) have been found to be key tool to enhance bioavailability or specific delivery to certain site of action. In this chapter, the uses of various polymeric materials for the development of NPs as drug delivery systems for various ailments have been described. The entrapment of bioactive compounds in PNPs systems is a hopeful move toward improvement of efficacy of drug toward the treatments of various diseases
Effect of Adhesion Promoter on Bond Strength of Reconditioned Brackets – an In vitro Study
Objectives: To compare the shear bond strength of recycled orthodontic metal brackets using an adhesion booster and conventional primer and using the Adhesive Remnant Index (ARI) score to assess the site of debonding.
Materials and Methods: Eighty premolar teeth were randomly divided into 3 groups of 20 teeth each: Group A-New brackets and Transbond XT, Group B-Recycled brackets and Transbond XT, Group C-Recycled brackets and Transbond XT + Enhance LC. Brackets were recycled using sandblaster. Bond strength was tested on a universal testing machine and remnant adhesive on the tooth surface was determined. Kruskal Wallis test and Mann Whitney test were carried out to know the significant difference between the groups. Chi – square test was used to determine significant differences in the ARI (Adhesive Remnant Index) scores.
Results: Highest mean load was recorded in Group A (9.58±1.72 MPa), followed by Group C (8.60±2.05 MPa) and Group B (6.39±1.64 MPa). Chi- square test indicated significant differences (P=.002) in ARI scores. Group A and Group C were associated significantly for score 2 of ARI; Group B for Score 0 of ARI.
Conclusion: The bond strength of recycled orthodontic brackets with Transbond XT was significantly lower when compared to bond strength of recycled brackets with an adhesion booster. After recycling the brackets with sandblaster and using an adhesion booster, the previously debonded brackets gave the bond strength comparable to new brackets with Transbond XT. The ARI data showed statistically significant association between the ARI scores and the groups
Corrigendum: Serological and molecular prevalence of Brucella spp. among livestock species in Rajasthan, India
Serological and molecular prevalence of Brucella spp. among livestock species in Rajasthan, India
A seroprevalence and molecular study was carried out in six districts of the state of Rajasthan, India to detect brucellosis in major livestock species. This study involves the testing of 3,245 livestock samples using the Rose Bengal Plate Test (RBPT), Indirect Enzyme-Linked Immunosorbent Assay (i-ELISA), and genus-specific polymerase chain reaction (PCR) markers for molecular diagnosis of the disease. In the tested samples, seroprevalence was 5.06% (CI: 1.96–8.15) using the RBPT test and 6.88% (CI: 1.98–11.78) using the i-ELISA test, while the cumulative seroprevalence (RBPT and i-ELISA) was 3.63% (CI: 0.44–6.83). The prevalence of the disease was 1.27% (CI: 0.56–3.11) when tested using molecular markers. The highest prevalence of brucellosis was detected in Cattle (7.00, 3.22%), followed by camels (5.50, 2.50%), buffalo (2.66, 0.00%), sheep (2.43, 0.41%), and goats (0.58, 0.23%) when serological (cumulative) and molecular diagnosis were considered preferred methods of detection. Cattle (3.22%) and camels (2.50%) also showed a high prevalence of disease when tested using molecular markers. The results of this study reveal that cattle, camel, and sheep brucellosis is prevalent in the study areas
Evaluation of Gamma glutamyl-transferase (GGT) levels in COVID-19: A retrospective analysis in tertiary care centre
Many recent studies have reported that patients infected with novel coronavirus 2019 or SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) might have a liver injury. However, few studies have focussed on the levels of Gamma glutamyl-transferase (GGT) alone and the variations associated with it. We retrospectively analysed the GGT levels of 476 admitted patients with confirmed COVID-19 in a tertiary care centre, PGIMER (Post Graduate Institute of Medical Education and Research), Chandigarh. Out of the total 476 COVID-19 patients studied, 35% had elevated GGT levels. ICU care was required for 51.19% (P <0.0001) of these patients and their hospital stay was of longer duration as compared to the patients with normal GGT levels. The incidence of GGT elevation was found to be more pronounced in males and elderly patients. The male population displayed higher GGT levels with 52% having raised levels compared to females where only 21.6% had elevated GGT levels. Although the number of COVID-19 cases was majorly from young age groups, the elevation in GGT levels has been reported more in elderly patients. GGT levels can therefore serve as a predictor for the extent of liver injury and severity in COVID-19 patients
Evaluation of Gamma glutamyl-transferase (GGT) levels in COVID-19: A retrospective analysis in tertiary care centre
681-686Many recent studies have reported that patients infected with novel coronavirus 2019 or SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) might have a liver injury. However, few studies have focussed on the levels of Gamma glutamyl-transferase (GGT) alone and the variations associated with it. We retrospectively analysed the GGT levels of 476 admitted patients with confirmed COVID-19 in a tertiary care centre, PGIMER (Post Graduate Institute of Medical Education and Research), Chandigarh. Out of the total 476 COVID-19 patients studied, 35% had elevated GGT levels. ICU care was required for 51.19% (P <0.0001) of these patients and their hospital stay was of longer duration as compared to the patients with normal GGT levels. The incidence of GGT elevation was found to be more pronounced in males and elderly patients. The male population displayed higher GGT levels with 52% having raised levels compared to females where only 21.6% had elevated GGT levels. Although the number of COVID-19 cases was majorly from young age groups, the elevation in GGT levels has been reported more in elderly patients. GGT levels can therefore serve as a predictor for the extent of liver injury and severity in COVID-19 patients
Validation of a noninvasive aMMP-8 point-of-care diagnostic methodology in COVID-19 patients with periodontal disease
Objectives: The aim of this study was to validate an active matrix metalloproteinase (MMP-8) point-of-care diagnostic tool in COVID-19 patients with periodontal disease. Subjects, Materials, and Methods: Seventy-two COVID-19-positive and 30 COVID-19-negative subjects were enrolled in the study. Demographic data were recorded, periodontal examination carried out, and chairside tests run for evaluating the expression of active MMP-8 (aMMP-8) in the site with maximum periodontal breakdown via gingival crevicular fluid sampling as well as via a mouth rinse-based kit for general disease activity. In COVID-19-positive patients, the kits were run again once the patients turned COVID-19 negative. Results: The overall (n = 102) sensitivity/specificity of the mouthrinse-based kits to detect periodontal disease was 79.41%136.76% and that of site-specific kits was 64.71%/55.88% while adjusting for age, gender, and smoking status increased the sensitivity and specificity (82.35%/76.47% and 73.53%/88.24, respectively). Receiver operating characteristic (ROC) analysis for the adjusted model revealed very good area under the ROC curve 0.746-0.869 (p < .001) and 0.740-0.872 (p < .001) (the aMMP-8 mouth rinse and site-specific kits, respectively). No statistically significant difference was observed in the distribution of results of aMMP-8 mouth rinse test (p = .302) and aMMP-8 site-specific test (p = .189) once the subjects recovered from COVID-19. Conclusions: The findings of the present study support the aMMP-8 point-of-care testing (PoCT) kits as screening tools for periodontitis in COVID-19 patients. The overall screening accuracy can be further increased by utilizing adjunctively risk factors of periodontitis. The reported noninvasive, user-friendly, and objective PoCT diagnostic methodology may provide a way of stratifying risk groups, deciding upon referrals, and in the institution of diligent oral hygiene regimens.Peer reviewe
Theranostic Potential of Adaptive Cold Atmospheric Plasma with Temozolomide to Checkmate Glioblastoma: An In Vitro Study
Cold atmospheric plasma (CAP) has been used for the treatment of various cancers. The anti-cancer properties of CAP are mainly due to the reactive species generated from it. Here, we analyze the efficacy of CAP in combination with temozolomide (TMZ) in two different human glioblastoma cell lines, T98G and A172, in vitro using various conditions. We also establish an optimized dose of the co-treatment to study potential sensitization in TMZ-resistant cells. The removal of cell culture media after CAP treatment did not affect the sensitivity of CAP to cancer cells. However, keeping the CAP-treated media for a shorter time helped in the slight proliferation of T98G cells, while keeping the same media for longer durations resulted in a decrease in its survivability. This could be a potential reason for the sensitization of the cells in combination treatment. Co-treatment effectively increased the lactate dehydrogenase (LDH) activity, indicating cytotoxicity. Furthermore, apoptosis and caspase-3 activity also significantly increased in both cell lines, implying the anticancer nature of the combination. The microscopic analysis of the cells post-treatment indicated nuclear fragmentation, and caspase activity demonstrated apoptosis. Therefore, a combination treatment of CAP and TMZ may be a potent therapeutic modality to treat glioblastoma. This could also indicate that a pre-treatment with CAP causes the cells to be more sensitive to chemotherapy treatment
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