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1.
Heliyon ; 10(10): e31270, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38826701

ABSTRACT

In the present article, we prove the sharp upper bounds for the second order Hankel determinants |H2(1)|,|H2(2)| and related functionals |a2a3-a4|, |a2a5-a3a4| for q-starlike functions. An upper bound for the third order Hankel determinant |H3(1)| along with the sharp upper bounds for Toeplitz determinant |Tm(n)|, where (m,n)∈{(2,2),(2,3),(3,1),(3,2)} are attained. Many known results are also obtained as corollaries of our main results.

2.
Nanomaterials (Basel) ; 13(7)2023 Mar 23.
Article in English | MEDLINE | ID: mdl-37049233

ABSTRACT

Ice accumulation on brass surfaces can lead to heat transfer inefficiency, equipment degradation, and potential accidents. To address this issue, superhydrophobic surface technology is utilized. This work aims to develop superhydrophobic nanostructured brass surfaces using the combination of nanolaser ablation and the deposition of silica nanoparticles to achieve the anti-icing property. Four distinct types of brass surfaces namely, the bare surface (BS), the lasered surface (LS), the coated surface (CS), and the coated-lasered surface (CLS) were prepared. The anti-icing performances of the fabricated samples including the effects of the surface structure, the droplet size, and the surface temperature were investigated and evaluated. The results showed that the delayed icing time increased with the increases in the apparent contact angle, the droplet size, and the surface temperature. When the apparent contact angle increased, the contact area between the droplet and the cooling substrate reduced, leading to the longer delayed icing time. With the deposition of silica nanoparticles and nanolaser treatment, CLS achieved the greatest apparent contact angle of 164.5°, resulting in the longest delayed icing time under all experimental conditions. The longest delayed icing time on CLS recorded in this study was 2584 s, which was 575%, 356%, and 27% greater than those on BS, LS, and CS, respectively. The study also revealed that the surface structure played a more crucial role in achieving the anti-icing property when compared to the surface temperature or the droplet size. The shortest delayed icing time on CLS at the lowest surface temperature and at the smallest droplet size was longer than those on BS and LS at all conditions. The results were also discussed in relation to a heat transfer model. The findings of this research can serve as an avenue for advancing knowledge on heat transfer enhancement and energy efficiency.

3.
Nat Commun ; 14(1): 2486, 2023 Apr 29.
Article in English | MEDLINE | ID: mdl-37120655

ABSTRACT

The origin of the diffuse gamma-ray background (DGRB), the one that remains after subtracting all individual sources from observed gamma-ray sky, is unknown. The DGRB possibly encompasses contributions from different source populations such as star-forming galaxies, starburst galaxies, active galactic nuclei, gamma-ray bursts, or galaxy clusters. Here, we combine cosmological magnetohydrodynamical simulations of clusters of galaxies with the propagation of cosmic rays (CRs) using Monte Carlo simulations, in the redshift range z ≤ 5.0, and show that the integrated gamma-ray flux from clusters can contribute up to 100% of the DGRB flux observed by Fermi-LAT above 100 GeV, for CRs spectral indices α = 1.5 - 2.5 and energy cutoffs [Formula: see text] eV. The flux is dominated by clusters with masses 1013 ≲ M/M⊙ ≲ 1015 and redshift z ≲ 0.3. Our results also predict the potential observation of high-energy gamma rays from clusters by experiments like the High Altitude Water Cherenkov (HAWC), the Large High Altitude Air Shower Observatory (LHAASO), and potentially the upcoming Cherenkov Telescope Array (CTA).

4.
Cell Metab ; 34(1): 125-139.e8, 2022 01 04.
Article in English | MEDLINE | ID: mdl-34986331

ABSTRACT

Concerted alteration of immune and metabolic homeostasis underlies several inflammation-related pathologies, ranging from metabolic syndrome to infectious diseases. Here, we explored the coordination of nucleic acid-dependent inflammatory responses and metabolic homeostasis. We reveal that the STING (stimulator of interferon genes) protein regulates metabolic homeostasis through inhibition of the fatty acid desaturase 2 (FADS2) rate-limiting enzyme in polyunsaturated fatty acid (PUFA) desaturation. STING ablation and agonist-mediated degradation increased FADS2-associated desaturase activity and led to accumulation of PUFA derivatives that drive thermogenesis. STING agonists directly activated FADS2-dependent desaturation, promoting metabolic alterations. PUFAs in turn inhibited STING, thereby regulating antiviral responses and contributing to resolving STING-associated inflammation. Thus, we have unveiled a negative regulatory feedback loop between STING and FADS2 that fine-tunes inflammatory responses. Our results highlight the role of metabolic alterations in human pathologies associated with aberrant STING activation and STING-targeting therapies.


Subject(s)
Fatty Acid Desaturases , Metabolic Syndrome , Fatty Acid Desaturases/genetics , Fatty Acid Desaturases/metabolism , Fatty Acids, Unsaturated/metabolism , Humans , Inflammation , Lipid Metabolism
5.
J Pak Med Assoc ; 71(Suppl 4)(8): S22-S25, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34469424

ABSTRACT

OBJECTIVE: To assess the problem of unlicensed practitioners and quacks in Sindh, Pakistan. METHODS: A cross-sectional study was conducted in 29 districts of Sindh province in Pakistan from December 2019 to January 2020. Initial data available with Sindh Health Department about locations where quacks were practicing was used to identify unlicensed practitioners. A structured questionnaire was developed which contained information about certification of practitioners and an observational checklist was developed to assess infection prevention and control practices (IPC) and injection safety. RESULTS: A total of 4315 private practitioners were inspected out of which 3022 (70%) were unlicensed health practitioners belonging to different categories. Within the six surveyed divisions of Sindh, the highest proportion of unlicensed practitioners were documented in Shaheed Benazirabad division (n=739; 24.5%) followed by Hyderabad (n=599; 19.8%). In Mirpur Khas, there were 510 (16.9%), in Karachi 310 (10.3%), in Sukkur 484 (16%) and in Larkana there were 380 (12.6%) unlicensed practitioners. Poor IPC was observed in 89.4% (3861/4315) of all health providers. Reuse of syringes and intravenous drip sets was observed among 78.7% (1916/2432) of the untrained providers across the province. It was also found that 155 MBBS doctors had given their names on rent to be used as a signboard outside the clinics of some of the unlicensed practitioners. CONCLUSION: The problem of quackery is widespread in the Sindh province. It can be proactively addressed by shutting down all unlicensed practitioners and educating the community to avoid visiting them in order to reduce the probability of exposure to unsafe healthcare practices.


Subject(s)
HIV Infections , Quackery , Cross-Sectional Studies , Disease Outbreaks , HIV Infections/epidemiology , HIV Infections/prevention & control , Humans , Pakistan/epidemiology
6.
Micromachines (Basel) ; 13(1)2021 Dec 23.
Article in English | MEDLINE | ID: mdl-35056182

ABSTRACT

Electrically tunable lenses (ETLs) are those with the ability to alter their optical power in response to an electric signal. This feature allows such systems to not only image the areas of interest but also obtain spatial depth perception (depth of field, DOF). The aim of the present study was to develop an ETL-based imaging system for quantitative surface analysis. Firstly, the system was calibrated to achieve high depth resolution, warranting the accurate measurement of the depth and to account for and correct any influences from external factors on the ETL. This was completed using the Tenengrad operator which effectively identified the plane of best focus as demonstrated by the linear relationship between the control current applied to the ETL and the height at which the optical system focuses. The system was then employed to measure amplitude, spatial, hybrid, and volume surface texture parameters of a model material (pharmaceutical dosage form) which were validated against the parameters obtained using a previously validated surface texture analysis technique, optical profilometry. There were no statistically significant differences between the surface texture parameters measured by the techniques, highlighting the potential application of ETL-based imaging systems as an easily adaptable and low-cost alternative surface texture analysis technique to conventional microscopy techniques.

7.
Pan Afr Med J ; 37: 174, 2020.
Article in English | MEDLINE | ID: mdl-33447329

ABSTRACT

The present study is to explore the factors and reasons behind public proneness towards quacks in the rural areas of Sindh, Pakistan and to manifest the public on how these quacks are duping vulnerable and quackery-prone peoples for financial gain which may induce human lives in life-threatening health conditions. The study also interprets a better understanding of the public needs, especially in the rural areas of the Sindh that may give a hope for deliverance from quacks.


Subject(s)
Physicians/standards , Quackery , Rural Population , Humans , Pakistan , Vulnerable Populations
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