This study investigated the changes in the physicochemical, microbiological, textural, and nutritional values of ice cream produced by various methods with the addition of different lactic acid ...bacteria. Adding lactic acid bacteria to the ice cream mix caused a decrease in firmness, consistency, cohesiveness, index of viscosity, pH, aw, first drop, complete melting, and overrun values (p < .05). These decreases were more pronounced in the samples to which lactic acid bacteria were added before mix maturation (p < .05). Firmness and consistency values varied between 15.11–16.26 (g) and 374.58–404.91 (g s), respectively, in the samples to which lactic acid bacteria were added before maturation. No significant effect of the addition of lactic acid bacteria to the ice cream mix on the L*, a*, and b* values of the bacteria before or after mix maturation was detected (p > .05). The L* values of the samples varied between 88.91 and 83.36, a* values between 0.76 and 1.32, and b* values between 6.57 and 8.38. An increase was detected in the amount of organic acid (excluding formic acid) in the samples produced with the addition of different lactic acid bacteria (p < .05). The number of fatty acids in the samples varied depending on the lactic acid addition and the production method; the rate of this change was generally higher in the samples with added lactic acid bacteria after mix maturation (p < .05). In particular, the amounts of short‐ and medium‐chain fatty acids increased in the samples with lactic acid bacteria added after mix ripening, compared to the control sample.
Ice cream, not typically considered a fermented dairy product, can be converted into one thanks to the lactic acid bacteria added to it, improving and altering its textural, sensory, and microbiological properties. The addition of lactic acid bacteria can also raise ice cream's functional and nutritional values. This study highlighted and examined the characteristics of ice cream made in various methods by adding various lactic acid bacteria.
High efficiency and long‐term stability are the prerequisites for the commercialization of perovskite solar cells (PSCs). However, inadequate and non‐uniform doping of hole transport layers (HTLs) ...still limits the efficiency improvements, while the intrinsic instability of HTLs caused by ion migration and accumulation is difficult to be addressed by external encapsulation. Here it is shown that the addition of a conjugated phosphonic acid (CPA) to the Spiro‐OMeTAD benchmark HTL can greatly enhance the device efficiency and intrinsic stability. Featuring an optimal diprotic‐acid structure, indolo(3,2‐b)carbazole‐5,11‐diylbis(butane‐4,1‐diyl) bis(phosphonic acid) (BCZ) is developed to promote morphological uniformity and mitigate ion migration across both perovskite/HTL and HTL/Ag interfaces, leading to superior charge conductivity, reinforced ion immobilization, and remarkable film stability. The dramatically improved interfacial charge collection endows BCZ‐based n‐i‐p PSCs with a champion power conversion efficiency of 24.51%. More encouragingly, the BCZ‐based devices demonstrate remarkable stability under harsh environmental conditions by retaining 90% of initial efficiency after 3000 h in air storage. This work paves the way for further developing robust organic HTLs for optoelectronic devices.
A conjugated phosphonic acid is developed to modify Spiro‐OMeTAD benchmark HTL, leading to superior charge conductivity, reinforced ion immobilization, and remarkable device stability.
Owing to low immunogenicity‐induced immune escape and short‐term circulating immune responses, the efficiency of immunotherapy is unsatisfactory. Therefore, triggering immunogenic cell death and ...establishing a long‐term, mutually reinforced treatment modality are urgent challenges. In this study, ultrathin CaBi2Nb2O9 nanosheets with tunable oxygen vacancies (abbreviated as CBNO‐OV1) are prepared for synergistic necroptosis and immunotherapy. The optimized vacancy concentration significantly improves the piezoelectric effect under ultrasound irradiation, thereby considerably improving the generation of reactive oxygen species (ROS). Density functional theory shows that oxygen vacancies can improve the efficiency of electron hole separation by suppressing their recombination, thus resulting in enhanced piezocatalytic activity. Moreover, the piezoelectric effect improves the permeability of tumor cell membranes, thus resulting in Ca2+ influx. Additionally, CBNO‐OV1 also releases a portion of Ca2+, which induces necroptosis assisted by explosive ROS. Ribonucleic acid transcription tests suggest the mechanisms associated with immune response activation and necroptosis. More importantly, necroptosis can trigger a significant immune response in vivo, thus activating macrophage M1 polarization through the NF‐kappa B pathway and promoting T‐cell differentiation.Tumor Necrosis Factor‐α differentiated from macrophages conversely promotes necroptosis, thus realizing a mutually enhanced effect. This study demonstrates the feasibility of mutually reinforced necroptosis and immunotherapy for amplifying tumor efficacy.
Ultrathin CaBi2Nb2O9 nanosheets with oxygen vacancies show a high piezocatalytic effect. Reactive oxygen species and overloaded Ca2+ upregulate the expression of RIPK3 and MIKL proteins, inducing the onset of necroptosis. Necroptosis induces a robust immune response by inducing DC maturation and macrophage M1 polarization. The secreted cytokine TNF‐α again enhances necroptosis. A mutual enhancement is thereby achieved.
In recent years, low Earth orbit (LEO) satellites have been frequently discussed for their benefits in positioning and navigation services as an augmentation to the global navigation satellite ...systems (GNSSs). Similar to the positioning concept based on ranging to GNSS satellites, precise positioning of single-receiver users needs high-accuracy orbits and clocks of LEO satellites as a pre-condition. For real-time users, high prediction accuracies of these orbits at different latencies are needed. Unlike the satellite clocks, the GNSS orbits can be typically predicted for hours with high accuracy. LEO satellites, however, face more complicated perturbing dynamic terms due to their low altitudes. Therefore, the prediction accuracy and integrity of their orbits need to be addressed. In this study, using real data of three test LEO satellites GRACE C, Sentinel-1A and Sentinel-3B of different altitudes, various reduced-dynamic prediction strategies are assessed, with the appropriate methods selected for different prediction times up to 6h. The global-averaged orbital user range errors (OUREs) are shown to be altitude-related. For the 700-800km Sentinel satellites and 500 km GRACE satellite, the RMS of the OUREs is at sub-dm and dm-level for the prediction time of 1h, respectively, and around 0.2m and 0.6 m at the prediction time of 6h, respectively. For integrity purposes, the worst-location OURE are calculated for the predicted orbits using a proposed algorithm considering the Earth as an Ellipsoid, not a sphere as usually done for the GNSS satellites. The orbital user range accuracy (OURA) is then evaluated for different prediction periods, having a time-dependent model proposed to compute the overbounding OURA at any prediction time within 6h. With an integrity risk of 10-5, using hourly quadratic polynomials as the time-dependent model, the overbounding OURA is around 0.1m at the prediction of 1h, and at the sub-meter level for the prediction of 6 h for the Sentinel satellites.
Efficiently transforming CO2 into renewable energy sources is crucial for decarbonization efforts. Formic acid (HCOOH) holds great promise as a hydrogen storage compound due to its high hydrogen ...density, non‐toxicity, and stability under ambient conditions. However, the electrochemical reduction of CO2 (CO2RR) on conventional carbon black‐supported metal catalysts faces challenges such as low stability through dissolution and agglomeration, as well as suffering from high overpotentials and the necessity to overcome the competitive hydrogen evolution reaction (HER). In this study, we modify the physical/chemical properties of metal surfaces by depositing metal monolayers on graphene (M/G) to create highly active and stable electrocatalysts. Strong covalent bonding between graphene and metal is induced by the hybridization of sp and d orbitals, especially the sharp
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orbitals of metals near the Fermi level, playing a decisive role. Moreover, charge polarization on graphene in M/G enables the deposition of another thin metallic film, forming metal/graphene/metal (M/G/M) structures. Finally, evaluating overpotentials required for CO2 reduction to HCOOH, CO, and HER, we find that Pd/G, Pt/G/Ag, and Pt/G/Au exhibit excellent activity and selectivity toward HCOOH production. Our novel 2D hybrid catalyst design methodology may offer insights into enhanced electrochemical reactions through the electronic mixing of metal and other p‐block elements.
Strong covalent bonding between metal monolayer and graphene driven by the sp and d orbital hybridization, 2D metal/graphene (M/G) system is investigated. The charge transfer from metal to graphene allows for the electrodeposition of another metal film, thus forming metal/graphene/metal (M/G/M) system. These 2D hybrid systems exhibit excellent activity and selectivity toward formic acid production over competitive hydrogen evolution reaction.
Chemical modification of aptamers is an important step to improve their performance and stability in biological media. This can be performed either during their identification (mod‐SELEX) or after ...the in vitro selection process (post‐SELEX). In order to reduce the complexity and workload of the post‐SELEX modification of aptamers, we have evaluated the possibility of improving a previously reported, chemically modified aptamer by combining enzymatic synthesis and nucleotides bearing bioisosteres of the parent cubane side‐chains or substituted cubane moieties. This method lowers the synthetic burden often associated with post‐SELEX approaches and allowed to identify one additional sequence that maintains binding to the PvLDH target protein, albeit with reduced specificity. In addition, while bioisosteres often improve the potency of small molecule drugs, this does not extend to chemically modified aptamers. Overall, this versatile method can be applied for the post‐SELEX modification of other aptamers and functional nucleic acids.
Post‐SELEX modification of aptamers allows to improve their performance but comes at the cost of uncertain and labor‐intensive structure activity relationship studies. Here, we have evaluated the possibility of improving a previously reported, chemically modified aptamer by combining enzymatic synthesis and nucleotides bearing bioisosteres of the parent cubane side‐chains or substituted cubane moieties. This method lowers the synthetic burden associated with post‐SELEX approaches and allowed to identify one additional sequence that maintains binding to the PvLDH target protein, albeit with reduced specificity.
Boron is the archetypal Lewis acid, and therefore it is only natural that it prefers to bind nitrogen, its usual Lewis base counterpart. To challenge this assumption, we present a computationally ...designed bicyclopentane molecule akin to 1.1.1propellane, but with pyramidal B and N inner atoms bonded by an “inverted” dative bond. Unexpectedly, the dimer of this system prefers to interact via an atypical boron‐boron bond over the supposedly obvious boron‐nitrogen bond. A molecular orbital analysis shows that the boron in this peculiar entity acts both as an electron donor and an electron acceptor, making the dimerization an amphoteric‐amphoteric interaction process.
A propellane‐like molecule with an internal N→B dative bond makes the scaffold for a dimer that prefers to bind through a unique boron‐boron amphoteric charge transfer interactions than through the conventional nitrogen‐boron Lewis acid pair.
Block copolymers utilizing oligomeric poly(pentylene‐co‐hexylene carbonate)diol modified with 2,4‐diisocyanatotoluene and further with 2‐bromo‐N‐(3‐hydroxypropyl)‐2‐methylpropanamide were synthesized ...and utilized as Activators ReGenerated by Electron Transfer Atom Transfer Radical Polymerization macroinitiators to obtain a first generation of multifunctional recycling additives with poly(glycidyl methacrylate‐co‐butyl methacrylate‐co‐methyl methacrylate) side chains, which could act as chain extenders. Then, chosen additive was reacted with a radical scavenger, 3,5‐ditertbutyl‐4‐hydroxybenzoic acid (DHBA), to obtain a second generation of reactive additives. Those copolymers had different numbers of epoxy groups per polymer chain, and different number of epoxides opened with DHBA, hence showed a range of properties, and were utilized as reactive modifiers for polylactide (PLA) extrusion melting. The first‐generation modifiers caused an increase in PLA's blends relative melt viscosity, stabilized material properties, and enhanced impact strength, while the second‐generation modifiers with more than 8 % of epoxide ring opened showed worse properties. However, they managed to suppress the UV degradation of PLA blend plates.
Multifunctional, reactive additives for PLA recycling, which could act both as antioxidants and chain extenders, were synthesized utilizing ARGET ATRP. They proved to stabilize and, in some cases, even improve PLA's viscosity and mechanical properties during long (30 minutes) extrusion, which imitated 5 recycling acts.
Introduction:
The aim of this review was to estimate the prevalence of refractive errors (RE) and uncorrected refractive error (URE) in school-aged children of 4 to 14 years of age in Saudi Arabia.
...Methods:
An extensive search was performed for peer-reviewed studies with data from the Saudi population during the past 20 years. The Cochrane Library, Pubmed, and Embase databases were used. Two independent reviewers evaluated publications and extracted the data. The quality of the studies was evaluated based on a critical appraisal tool designed for systematic reviews. The pooled prevalence of refractive error, uncorrected refractive error and different types of refractive error were estimated by using the random-effects meta-analysis.
Results and Discussion:
Eight school-based studies were included in this review. Among the overall pooled population of 12,247childern, the estimated prevalence of refractive error was 17.5% (95% CI: 11.1- 25). In the five studies that reported uncorrected refractive error (N=10,198), the pooled prevalence was 16.8% (95% CI: 11.4 – 21.3). The overall prevalence of refractive errors was very similar among boys, 16.8 (95% CI: 10.8- 24.1), and girls, 17.7% (95% CI: 10.2 – 25.9). Myopia was the most prevalent refractive error and was present in 40.8% (95% CI: 16.1 – 69.9) followed by astigmatism 29.7% (95% CI: 6.1- 61.7) and hyperopia 28.3% (95% CI: 16.9 – 41.2).
Conclusion:
This review highlights the high prevalence of refractive errors and uncorrected refractive error among children in Saudi Arabia. More studies are required using standardised methods in different regions where there is a lack of information on UREs. It is recommended that vision screening programs of children for RE should be implemented at the community level and integrated into school health programmes in order to detect UREs and prevent amblyopia, which is one of the debilitating consequences of URE.
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