Development of a Highly Selective,Sensitive, and Fast Response Upconversion Luminescent Platform for Hydrogen Sulfide Detection

Hydrogen sulfide (H₂S) has been recognized as one of most important gaseous signaling molecules mediated by a variety of physiological and pathological processes. Yet, its functions remain largely elusive due to the lack of potent monitoring methods. Hereby this issue is addressed with a powerful new platform—dye‐assembled upconversion nanoparticles (UCNPs). A series of chromophores with different absorption bands and fast responses towards H₂S is combined with UCNPs and results in a library of H₂S sensors with responsive emission signals ranging from the visible to the near‐infrared (NIR) region. These nanoprobes demonstrate highly selective and rapid responses to H₂S in vitro and in cells. Furthermore, H₂S levels in blood can be detected using the developed nanoprobes. Hence the reported H₂S sensing platform can serve as a powerful diagnostic tool to research H₂S functions and to investigate H₂S‐related diseases.     

Nanosuspension of efavirenz for improved oral bioavailability: formulation optimization,in vitro,in situ and in vivo evaluation

Context: Nanosuspensions (NSs) of poorly water-soluble drugs are known to increase the oral bioavailability.

Objectives: The purpose of this study was to develop NS of efavirenz (EFV) and to investigate its potential in enhancing the oral bioavailability of EFV.

Materials and methods: EFV NS was prepared using the media milling technique. The Box–Behnken design was used for optimization of the factors affecting EFV NS. Sodium lauryl sulfate and PVP K30 were used to stabilize the NS. Freeze-dried NS was completely re-dispersed with double-distilled filtered water.

Results: Mean particle size and zeta potential of the optimized NS were found to be 320.4?±?3.62?nm and –32.8?±?0.4 mV, respectively. X-ray diffraction and differential scanning calorimetric analysis indicated no phase transitions. Rate and extent of drug dissolution in the dissolution medium for NS was significantly higher compared to marketed formulation. The parallel artificial membrane permeability assay revealed that NS successfully enhanced the permeation of EFV. Results of in situ absorption studies showed a significant difference in absorption parameters such as K_a, t_1/2 and uptake percentages between lyophilized NS and marketed formulation of EFV. Oral bioavailability of EFV in rabbits resulting from NS was increased by 2.19-fold compared to the marketed formulation.

Conclusion: Thus, it can be concluded that NS formulation of EFV can provide improved oral bioavailability due to enhanced solubility, dissolution velocity, permeability and hence absorption.     

Interface Trap Charges Analysis on DC and High Frequency Characteristics of UTBB-FDSOI FET

Silicon - In this paper, we have studied effect of localised charges on performance of UTBB FDSOI FET. Purpose behind this work is to understand the performance of UTBB FDSOI FET under the...     

Haploinsufficiency of a Circadian Clock Gene Bmal1 (Arntl or Mop3) Causes Brain-Wide mTOR Hyperactivation and Autism-like Behavioral Phenotypes in Mice

Approximately 50–80% of children with autism spectrum disorders (ASDs) exhibit sleep problems, but the contribution of circadian clock dysfunction to the development of ASDs remains largely unknown. The essential clock gene Bmal1 (Arntl or Mop3) has been associated with human sociability, and its missense mutation is found in ASD. Our recent study found that Bmal1-null mice exhibit a variety of autism-like phenotypes. Here, we further investigated whether an incomplete loss of Bmal1 function could cause significant autism-like behavioral changes in mice. Our results demonstrated that heterozygous Bmal1 deletion (Bmal1^+/−) reduced the Bmal1 protein levels by ~50–75%. Reduced Bmal1 expression led to decreased levels of clock proteins, including Per1, Per2, Cry 1, and Clock but increased mTOR activities in the brain. Accordingly, Bmal1^+/− mice exhibited aberrant ultrasonic vocalizations during maternal separation, deficits in sociability and social novelty, excessive repetitive behaviors, impairments in motor coordination, as well as increased anxiety-like behavior. The novel object recognition memory remained intact. Together, these results demonstrate that haploinsufficiency of Bmal1 can cause autism-like behavioral changes in mice, akin to those identified in Bmal1-null mice. This study provides further experimental evidence supporting a potential role for disrupted clock gene expression in the development of ASD.     

Peracetic acid bleaching of banana fibre: Process optimisation

Banana is an important commercially available natural fibre, suitable for making coarse yarns. It has also potential for making fine home and apparel textiles after requisite chemical intervention or blending with other fine fibres. For making such products, chemical processing, namely bleaching, coloration and finishing, play an important role. Bleaching of fibre is generally carried out in highly alkaline condition and at high temperature of 85°C using hydrogen peroxide to achieve whiteness index of > 70 with about 25% loss in tensile strength. To achieve a similar whiteness index, while addressing strength loss, a fibre friendly low-temperature low-alkali based peracetic acid (PAA) bleaching of banana fibre has been proposed in the present article. Important bleaching process parameters, namely PAA concentration (10–30 g/L), time (60–180 min) and temperature (60–80°C), have been varied for optimisation of the bleaching process. Banana fibre bleaching using PAA concentration of 20 g/L at 70°C for 2 h can produce fibre with whiteness index of > 70, which is suitable for subsequent coloration. The PAA bleached banana fibre can retain 84% of its bundle strength and 95.6% of its weight. Physical (strength, fineness), chemical (attenuated total reflectance Fourier-transform infrared [ATR-FTIR], energy dispersive X-ray spectroscopy [EDX]), optical (colour) and morphological (scanning electron microscopy [SEM]) properties of banana fibres before and after bleaching were evaluated to study the efficacy of the process.     

Characterization of a Cyclic Nucleotide‐Activated K+ Channel and its Lipid Environment by Using Solid‐State NMR Spectroscopy

Voltage‐gated ion channels are large tetrameric multidomain membrane proteins that play crucial roles in various cellular transduction pathways. Because of their large size and domain‐related mobility, structural characterization has proved challenging. We analyzed high‐resolution solid‐state NMR data on different isotope‐labeled protein constructs of a bacterial cyclic nucleotide‐activated K⁺ channel (MlCNG) in lipid bilayers. We could identify the different subdomains of the 4×355 residue protein, such as the voltage‐sensing domain and the cyclic nucleotide binding domain. Comparison to ssNMR data obtained on isotope‐labeled cell membranes suggests a tight association of negatively charged lipids to the channel. We detected spectroscopic polymorphism that extends beyond the ligand binding site, and the corresponding protein segments have been associated with mutant channel types in eukaryotic systems. These findings illustrate the potential of ssNMR for structural investigations on large membrane‐embedded proteins, even in the presence of local disorder.     

Senescent CD4+CD28− T Lymphocytes as a Potential Driver of Th17/Treg Imbalance and Alveolar Bone Resorption during Periodontitis

Senescent cells express a senescence-associated secretory phenotype (SASP) with a pro-inflammatory bias, which contributes to the chronicity of inflammation. During chronic inflammatory diseases, infiltrating CD4⁺ T lymphocytes can undergo cellular senescence and arrest the surface expression of CD28, have a response biased towards T-helper type-17 (Th17) of immunity, and show a remarkable ability to induce osteoclastogenesis. As a cellular counterpart, T regulatory lymphocytes (Tregs) can also undergo cellular senescence, and CD28⁻ Tregs are able to express an SASP secretome, thus severely altering their immunosuppressive capacities. During periodontitis, the persistent microbial challenge and chronic inflammation favor the induction of cellular senescence. Therefore, senescence of Th17 and Treg lymphocytes could contribute to Th17/Treg imbalance and favor the tooth-supporting alveolar bone loss characteristic of the disease. In the present review, we describe the concept of cellular senescence; particularly, the one produced during chronic inflammation and persistent microbial antigen challenge. In addition, we detail the different markers used to identify senescent cells, proposing those specific to senescent T lymphocytes that can be used for periodontal research purposes. Finally, we discuss the existing literature that allows us to suggest the potential pathogenic role of senescent CD4⁺CD28⁻ T lymphocytes in periodontitis.     

A numerical model to predict the powder–binder separation during micro-powder injection molding

The micro-powder injection molding (micro-PIM) process has the potential to bridge the gap between the design and manufacturing of micro-components that are often used in small and handy devices. Numerical modeling helps to analyze and overcome various difficulties of micro-PIM. In the present work, a numerical model is developed to predict the powder–binder separation (a common defect in PIM and especially severe in micro-PIM) during the injection of an alumina feedstock. A powder–binder separation criterion is proposed dealing with applied injection pressure and friction force between the powder and binder. An indirect comparison of feedstock travel time between two locations is used to validate the model. The predicted segregation from the simulated result is supported by a qualitative experimental measurement. The developed model can be used to optimize injection parameters to get a defect-free product.     

A sustainability root cause analysis methodology and its application

In the design of chemical/energy production systems, a major challenge is to identify the bottleneck issues and improve its sustainability effectively. Due to the multi-dimensional feature of sustainability, how to account for the impacts of various design factors and the cause-and-effect relationships can be very difficult. This paper will present a sustainability root cause analysis method based on the combination of Pareto Analysis and Fishbone diagram. The sustainability of the process is assessed incorporating economic, environmental, societal and efficiency concerns.This methodology is able to help the designers focus the attention on the most important fundamental causes, discover opportunities for sustainability improvement and provide critical guidance to design for sustainability. The efficacy of this methodology will be demonstrated through a case study on a biodiesel production technology.     

Coalescence of bubbles and stability of foams in aqueous solutions of Tween surfactants

Coalescence of air bubbles and stability of foams in aqueous solutions of Tween 20, 40, 60 and 80 are reported in this work. Adsorption of the surfactants at air–water interface was studied by measuring the surface tension of the surfactant solutions. The surface tension profiles were fitted using a surface equation of state derived from the Gibbs and Langmuir adsorption equations. The critical micelle concentration and surface tension at this concentration were determined. The effect of surfactant concentration on coalescence of air bubbles at flat air–water interface was studied. The role of steric force on coalescence time was investigated. The coalescence time distributions were fitted by the stochastic model. The mean values of the distributions were compared with the predictions of seven film-drainage models. Stability of foams was analyzed by the Ross–Miles test. The initial and residual foam heights were measured at different surfactant concentrations. The stability of foams was compared with the coalescence time of the bubbles.