Novel amine‐functionalized symmetrical squaraine (SQ)‐dye and fluorescein isothiocyanate (FITC)–SQ–FITC dye conjugate are designed and successfully synthesized, followed by their structural and ...photophysical characterizations. Symmetrical SQ dye exhibits complete fluorescence quenching in polar solvents, which is explained by considering photoinduced electron transfer (PET) as a dominant quenching pathway. In contrast, FITC–SQ–FITC dye conjugate results in a decrease in an aggregation of both SQ and FITC units and about 47 times enhancement in the far‐red fluorescence appearing at 674 nm. This profound enhancement in the far‐red fluorescence is explained by the synergistic influence of suppression of aggregation‐induced quenching (ACQ) and PET. This newly designed FITC–SQ–FITC dye conjugate shows complete quenching of the far‐red fluorescence in phosphate buffer saline (PBS) owing to very strong dye aggregation, as confirmed by spectral absorption investigation. In PBS, it strongly interacts with bovine serum albumin (BSA) (Ka = 1.1 × 104 m−1) used as a model protein breaking the dye aggregation by BSA and increasing far‐red fluorescence associated with SQ as a function of increasing BSA concentration. A profound 117 times increase in fluorescence at 674 nm with 25 times of BSA concentration suggests that the designed FITC–SQ–FITC is an excellent far‐red probe for dye‐protein interaction.
Photoinduced electron transfer‐based novel fluorescein isothiocyanate (FITC) flanked squaraine (SQ) dye FITC‐SQ‐FITC is designed and synthesized showing fluorescence in the far‐red region. There is a 47‐fold enhancement in fluorescence as compared to the parent amine‐functionalized SQ dye. Appreciably good binding with bovine serum albumin has a modest increase in fluorescence intensity by 117‐fold.
Dickinsonia tenuis
, an important Ediacaran element, reported from the Maihar Sandstone by Retallack et al. (2021) was re-examined in the field to ascertain the biogenicity of the purported fossils. ...Field observations, outcrop features, and laboratory analyses (XRD, Raman Spectroscopy) do not support the biogenicity and syngenecity of reported objects. Based on this discovery, the inferences drawn about the age of the Maihar Sandstone and the palaeogeographic position of India are therefore considered invalid. Indian
Dickinsonia
specimen described by Retallack et al. (2021) is a left-over impression of a fallen beehive which is further proved by the detailed Raman Spectroscopy and X-Ray Diffraction (XRD) analyses.
Bifacial dye-sensitized solar cells (DSSCs) were fabricated utilizing dye cocktails of two dyes, Z-907 and SQ-140, which have complementary light absorption and photon harvesting in the visible and ...near-infrared wavelength regions, for panchromatic photon harvesting. The investigation of the rate of dye adsorption and the binding strengths of the dyes on mesoporous TiO
corroborated the finding that the Z-907 dye showed a rate of dye adsorption that was about >15 times slower and a binding that was about 3 times stronger on mesoporous TiO
as compared to SQ-140. Utilizing the dye cocktails Z-907 and SQ-140 from ethanol, the formation of the dye bilayer, which was significantly influenced by the ratio of dyes and adsorption time, was demonstrated. It was demonstrated that the dyes of Z-907 and SQ-140 prepared in 1:9 or 9:1 molar ratios favoured the dye bilayer formation by subtly controlling the adsorption time. In contrast, the 1:1 ratio counterpart was prone to form mixed dye adsorption; the best performance of the BF-DSSCs was shown when a dye cocktail of Z-907 and SQ-140 in a molar 9:1 ratio was used to prepare a photoanode for 1 h of dye adsorption. The BF-DSSCs thus exhibited PCEs of 4.23% and 3.48% upon the front and rear side light illuminations, a cumulated PCE of 7.71%, and a very good BBF of 83%.
We present the results of a detailed investigation of the prompt and afterglow emission in the High Energy Stereoscopic System (H.E.S.S.)-detected GRB 190829A. Swift and Fermi observations of the ...prompt phase of this gamma-ray burst (GRB) reveal two isolated subbursts or episodes, separated by a quiescent phase. The energetic and the spectral properties of the first episode are in stark contrast to the second. The first episode, which has a higher spectral peak ∼120 keV and a low isotropic energy ∼1050 erg is an outlier to the Amati correlation and marginally satisfies the Yonetoku correlation. However, the energetically dominant second episode has lower peak energy and is consistent with the above correlations. We compared this GRB to other low-luminosity GRBs (LLGRBs). Prompt emission of LLGRBs also indicates a relativistic shock breakout origin of the radiation. For GRB 190829A, some of the properties of a shock breakout origin are satisfied. However, the absence of an accompanying thermal component and energy above the shock breakout critical limit precludes a shock breakout origin. In the afterglow, an unusual long-lasting late-time flare of duration ∼104 s is observed. We also analyzed the late-time Fermi Large Area Telescope (LAT) emission that encapsulates the H.E.S.S. detection. Some of the LAT photons are likely to be associated with the source. All of the above observational facts suggest GRB 190829A is a peculiar low-luminosity GRB that is not powered by a shock breakout, and has an unusual rebrightening due to patchy emission or a refreshed shock during the afterglow. Furthermore, our results show that teraelectronvolt-energy photons seem common in both high-luminosity GRBs and LLGRBs.
Therapy for multiple myeloma (MM) has markedly changed in the past decade with the introduction of new drugs, but it is not clear whether the improvements have been sustained. We studied 1038 ...patients diagnosed between 2001 and 2010, grouping patients into two 5-year periods by diagnosis, 2001-2005 and 2006-2010. The median estimated follow-up for the cohort was 5.9 years with 47% alive at the last follow-up. The median overall survival (OS) for the entire cohort was 5.2 years: 4.6 years for patients in the 2001-2005 group compared with 6.1 years for the 2006-2010 cohort (P=0.002). The improvement was primarily seen among patients over 65 years, the 6-year OS improving from 31 to 56%, P<0.001. Only 10% of patients died during the first year in the latter group, compared with 16% in the earlier cohort (P<0.01), suggesting improvement in early mortality. The improved outcomes were linked closely to the use of one or more new agents in initial therapy. The current results confirm continued survival improvement in MM and highlight the impact of initial therapy with novel agents. Most importantly, we demonstrate that the improved survival is benefitting older patients and that early mortality in this disease has reduced considerably.
Considering the applications and a great significance of the study pertaining to generalized functions in applied sciences, the author investigated the Lorenzo–Hartley’s function which is a ...generalization of classical functions widely used in fractional calculus. The Laplace transform pairs are derived and the requirements for the Lorenzo–Hartley’s function
G
ν
,
μ
,
δ
(
a
,
c
,
t
)
to be completely monotonic (for
t
>
0
) are investigated. The author has shown the applications of this generalized function to describe the relaxation models, particularly in dielectrics. The Lorenzo–Hartley’s function
G
ν
,
μ
,
δ
(
a
,
c
,
t
)
of a real variable
t
is considered to investigate a computable mathematical framework for standard Debye and non-Debye relaxation processes in dielectric materials. The non-negative spectral distribution function is obtained for the corresponding response function. It is also demonstrated that the classical models like Cole–Cole (C–C), Davidson–Cole (D–C), and Havriliak–Negami (H–N) for non-Debye relaxation and standard Debye relaxation are the particular cases of the Lorenzo–Hartley’s function. Some of the study cases are also worked out to visualize the effects of variations of parameters on the response function and corresponding spectral distribution function. A generalized and unified fractional relaxation differential equation which governs response functions for classical dielectrics models pertaining to non-Debye relaxation (C–C, D–C, and H–N) is also established in the present investigation.
Aneurysmal subarachnoid hemorrhage (aSAH) continues to be associated with significant morbidity and mortality despite advances in care and aneurysm treatment strategies. Cerebral vasospasm continues ...to be a major source of clinical worsening in patients. We intended to review the clinical and experimental aspects of aSAH and identify strategies that are being evaluated for the treatment of vasospasm. A literature review on aSAH and cerebral vasospasm was performed. Available treatments for aSAH continue to expand as research continues to identify new therapeutic targets. Oral nimodipine is the primary medication used in practice given its neuroprotective properties. Transluminal balloon angioplasty is widely utilized in patients with symptomatic vasospasm and ischemia. Prophylactic “triple‐H” therapy, clazosentan, and intraarterial papaverine have fallen out of practice. Trials have not shown strong evidence supporting magnesium or statins. Other calcium channel blockers, milrinone, tirilazad, fasudil, cilostazol, albumin, eicosapentaenoic acid, erythropoietin, corticosteroids, minocycline, deferoxamine, intrathecal thrombolytics, need to be further investigated. Many of the current experimental drugs may have significant roles in the treatment algorithm, and further clinical trials are needed. There is growing evidence supporting that early brain injury in aSAH may lead to significant morbidity and mortality, and this needs to be explored further.
Abstract
We have carried out a long-term infrared and X-ray investigation of the colliding-wind binary WR 125 (WC7 + O9III). The source was monitored using AstroSat Soft X-ray Telescope and the Tata ...Institute of Fundamental Research Near Infrared Imaging Camera-II mounted at the back of 3.6 m Devasthal Optical Telescope. WR 125 appeared brighter in the near-infrared
K
-band during the years 2017–2021 which is attributed to another episode of dust formation similar to the one reported during the likely periastron passage at the beginning of the 1990s. This is further supported by enhanced emission observed in the W1 and W2 bands of Wide-field Infrared Survey Explorer from 2018–2019. By combining archival X-ray data sets with our new measurements, long-term variations have been noticed. The source reaches a lower emission state in 2020 June (close to the recent infrared maximum) which could be due to enhanced absorption of X-rays produced in the colliding-wind region by the WC stellar wind close to the periastron in an eccentric orbit. The time interval between the previous and latest X-ray low states may indicate an orbital period of 28–29 years, in fair agreement with the recurrence time of episodic dust production. We also discuss published radio measurements in the context of a common picture based on a long-period binary scenario. These results allow us to draw relevant guidelines for future multiwavelength observations of WR 125.
Aim: To isolate an endophytic bacterial community associated with bryophytes, which were collected from various locations in Mount Abu, Rajasthan, and to characterise their morphological, ...biochemical, and biofilm development properties. Methodology: Different bryophytes were selected from various regions of Mount Abu, Rajasthan. On an R2A agar plate, colonies with various morphologies were isolated. Biofilm development of bacterial isolates was done on a glass surface and visualised through scaning electron microscopy. Biochemical test, such as indole test, catalase test, urease test, MR and VP tests, citrate utilization test, gelatine and nitrate test, etc., were determined as per Berge’s Manual of Determinative Bacteriology for characterization of endophytic bacteria. Salkowski's technique was also used for estimating IAA production by endophytic bacteria. Results: The results confirmed that isolates belonged to two phyla groups, Firmicutes and γ-proteobacteria with predomination of Firmicutes. Scanning electron microscopy showed that among all the isolates, rod-shaped bacteria dominated. The metabolic properties of endophytic bacteria showed that most bacterial isolates metabolised glucose, maltose and sucrose, however, only few bacterial endophytes metabolized lactose. Some isolates produced IAA growth hormones, which were analysed through Salkowski's technique. Interpretation: The findings indicate that bryophytes have associated bacterial diversity. The morphological and biochemical characterization of bacteria revealed that they are members of the Firmicutes and γ-proteobacteria phyla. SEM confirmed that bacterial isolates can form biofilm on glass surfaces and produce a distinct amount of IAA in a tryptophan-supplemented medium, essential for the growth and development of bryophytes. Key words: Bryophytes, Biofilm, Endophytic bacteria
Chymotrypsin, a crucial enzyme in human digestion, catalyzes the breakdown of milk proteins, underscoring its significance in both health diagnostics and dairy quality assurance. Addressing the ...critical need for rapid, cost-effective detection methods, we introduce a groundbreaking approach utilizing far-red technology and HOMO-Förster resonance energy transfer (FRET). Our novel probe, SQ-122 PC, features a unique molecular design that includes a squaraine dye (SQ), a peptide linker, and SQ moieties synthesized through solid-phase peptide synthesis. Demonstrating a remarkable quenching efficiency of 93.75% in a tailored H
O:DMSO (7:3) solvent system, our probe exhibits absorption and emission properties within the far-red spectrum, with an unprecedented detection limit of 0.130 nM. Importantly, our method offers unparalleled selectivity towards chymotrypsin, ensuring robust and accurate enzyme detection. This pioneering work underscores the immense potential of far-red-based homo-FRET systems in enabling the sensitive and specific detection of chymotrypsin enzyme activity. By bridging the gap between cutting-edge technology and biomedical diagnostics, our findings herald a new era of enzyme sensing, promising transformative advancements in disease diagnosis and dairy quality control.
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