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In wettability study, surface free energy interactions are of crucial importance for silica aerogels in which absorption of organic liquids and transportation of chemicals carried out for chemical and biotechnological applications. In present study, we have used Lifshitz–van der Waals/acid–base approach for calculation of surface free energy of aerogel sample. We have investigated that the surface free energy values of aerogels are 45.95, 51.42 and 45.69 mJ/m 2 by modifying their surfaces using 7 % chlorotrimethylsilane (TMCS), dimethyldichlorosilane (DMDCS) and hexamethyldisilazane (HMDZ) silylating reagents with solvent, respectively. The alcogels were prepared by two step acid–base catalyzed process where the molar ratio of precursors tetraethoxysilane:methanol:oxalic acid:NH 4 OH:NH 4 F was kept at optimal value of 1:16.5:0.71:0.58:0.60:0.98, respectively. To modify gel surfaces, TMCS, DMDCS and HMDZ concentration have been varied from 5 to 12 % and such alcogels were dried at ambient pressure. The aerogels have been characterized by fourier transform infrared spectroscopy, scanning electron microscopy, thermo-gravimetric and differential thermal analysis and Wetting properties of silica aerogel surfaces was studied by contact angle measurements. The surface chemical composition of DMDCS modified silica aerogels was studied by using X-ray photoelectron spectroscopy. As there is not any direct method, we have used Lifshitz–van der Waals/acid–base approach which gives, polar and non-polar components of aerogels surface free energy.

: A simple fabrication method towards a novel morphology followed by hydrophobic and pencil scratch resistant film based on silica nanoparticles was successfully achieved from methyltrimethoxysilane on glass by spin coating technique. The polyvinyl alcohol was employed for grafting the microporous network of the silica nanoparticles. The enrichment in hydrophobicity and pencil scratch resistance properties of the silica nanoparticles was achieved by adapting a polymer route. Since, the silica particles are in the nanometer size the films are excellent in transmission of light in the visible region. The water drop contact angle was high, up to ~169 ± 1°, for 10 μL volume of water and the sliding angle was achieved minimum to 5 ± 1°. Non-wetting property was tested by keeping the film in the humidity chamber for over 60 days. The silica film demonstrated resistance to scratches by a pencil of 4 H grade as per the ASTM D 3363 method. The feasible potential approach towards the fabrication of the superhydrophobic silica film with tailored nanoporous network and scratch resistant assets is indispensable for many practical applications.

Wettability of solid surfaces is an important property, which depends on both the surface chemistry and surface roughness. The present paper describes the room temperature synthesis of dip coated water repellent silica coatings on glass substrates using phenyltrimethoxysilane (PTMS) as a co-precursor with two-step sol–gel process. Silica sol was prepared by keeping the molar ratio of tetraethylorthosilicate precursor, methanol solvent, acidic water (0.001 M oxalic acid) and basic water (12 M NH 4 OH) constant at 1:11.03:0.17:0.58 respectively, throughout the experiments and the PTMS weight percentage was varied from 0 to 15 %. It was found that with an increase in wt% of PTMS, the roughness and hydrophobicity of the films increased. However, the optical transmission decreased from 93 to 82 % in the visible range. The hydrophobic silica films retained their hydrophobicity up to a temperature of 386 °C and above this temperature the films became hydrophilic. The hydrophobic silica thin films were characterized by taking into consideration the surface roughness studies, Fourier transform infrared spectroscopy, percentage of optical transmission, scanning electron microscopy, thermogravimetric–differential thermal analysis and contact angle measurements.

The effect of anodic deposition potential on the supercapacitance of manganese dioxide (MnO2) and effect of surface free energy (SFE) on the supercapacitance are discussed. MnO2 thin films have been synthesized using a potentiostatic electrodeposition method. Their structure, morphology, wettability, electrochemical properties and supercapacitance are discussed. The observed specific capacitance (Cs) of MnO2 thin films is 127 F/g for the deposition potential at 1.20 V/Ag/AgCl. These films also show better stability for over 1000 cycles. The porous MnO2 thin films lead to high SFE and a corresponding high value of specific capacitance.

Biomaterials and wettability have played a crucial role in the biocompatibility with a host matrix of body fluid and cells. We discuss designing superhydrophobic biomaterials for novel applications such as temporally implant, contact lenses, controlled drug release coatings, coating on medical instruments, etc. Such Superhydrophobic coating surfaces were created with the simple dip coating method by single step base catalyst sol-gel method. Methyltriethoxysilane/trimethoxymethylsilane-based deposition at different dip periods introduces interesting properties in the region, including superhydrophobicity, biocompatibility and transparency. This works reveal the impact of interaction bone marrow mesenchymal stem cells and surface free energy on the biocompatibility of superhydrophobic biomaterial. Graphical Abstract

A facile method was developed for the fabrication of the methyltriethoxysilane based transparent and superhydrophobic coating on glass substrates. The transparent and hydrophobic coatings were deposited on the glass substrates, using spray deposition method followed by surface modification process. A spray deposition method generates hierarchical morphology and post surface modification with monofunctional trimethylchlorosilane decreases the surface free energy of coating. These combined effects of synthesis produces bio-inspired superhydrophobic surface. The deposited coating surface shows high optical transparency, micro-nano scale hierarchical structures, improved hydrophobic thermal stability, static water contact angle of about 167° ± 1°, low sliding angle about 2° ± 1° and stable superhydrophobic nature. This paper provides the very simple sol–gel approach to the fabrication of optically transparent, thermally stable superhydrophobic coating on glass substrates. This fabrication strategy may easily extend to the industrial scale up and high-technology fields.

The Polarity/Protusion model of UNC-6/Netrin function in axon repulsion does not rely on a gradient of UNC-6/Netrin. Instead, the UNC-5 receptor polarizes the VD growth cone such that filopodial protrusions are biased to the dorsal leading edge. UNC-5 then inhibits growth cone protrusion ventrally based upon this polarity, resulting in dorsally-biased protrusion and dorsal migration away from UNC-6/Netrin. While previous studies have shown that UNC-5 inhibits growth cone protrusion by destabilizing actin, preventing microtubule + end entry, and preventing vesicle fusion, the signaling pathways involved are unclear. The SRC-1 tyrosine kinase has been previously shown to physically interact with and phosphorylate UNC-5, and to act with UNC-5 in axon guidance and cell migration. Here, the role of SRC-1 in VD growth cone polarity and protrusion is investigated. A precise deletion of src-1 was generated, and mutants displayed unpolarized growth cones with increased size, similar to unc-5 mutants. Transgenic expression of src-1(+) in VD/DD neurons resulted in smaller growth cones, and rescued growth cone polarity defects of src-1 mutants, indicating cell-autonomous function. Transgenic expression of a putative kinase-dead src-1(D831A) mutant caused a phenotype similar to src-1 loss-of-function, suggesting that this is a dominant negative mutation. The D381A mutation was introduced into the endogenous src-1 gene by genome editing, which also had a dominant-negative effect. Genetic interactions of src-1 and unc-5 suggest they act in the same pathway on growth cone polarity and protrusion, but might have overlapping, parallel functions in other aspects of axon guidance. src-1 function was not required for the effects of activated myr :: unc-5 , suggesting that SRC-1 might be involved in UNC-5 dimerization and activation by UNC-6, of which myr :: unc-5 is independent. In sum, these results show that SRC-1 acts with UNC-5 in growth cone polarity and inhibition of protrusion.

Background Surgical site infections (SSI) are one of the most common healthcare associated infections in the low-middle income countries. Data on incidence and risk factors for SSI following surgeries in general and Obstetric and Gynecological surgeries in particular are scare. This study set out to identify risk factors for SSI in patients undergoing Obstetric and Gynecological surgeries in an Indian rural hospital. Methods Patients who underwent a surgical procedure between September 2010 to February 2013 in the 60-bedded ward of Obstetric and Gynecology department were included. Surveillance for SSI was based on the Centre for Disease Control (CDC) definition and methodology. Incidence and risk factors for SSI, including those for specific procedure, were calculated from data collected on daily ward rounds. Results A total of 1173 patients underwent a surgical procedure during the study period. The incidence of SSI in the cohort was 7.84% (95% CI 6.30–9.38). Majority of SSI were superficial. Obstetric surgeries had a lower SSI incidence compared to gynecological surgeries (1.2% versus 10.3% respectively). The risk factors for SSI identified in the multivariate logistic regression model were age (OR 1.03), vaginal examination (OR 1.31); presence of vaginal discharge (OR 4.04); medical disease (OR 5.76); American Society of Anesthesia score greater than 3 (OR 12.8); concurrent surgical procedure (OR 3.26); each increase in hour of surgery, after the first hour, doubled the risk of SSI; inappropriate antibiotic prophylaxis increased the risk of SSI by nearly 5 times. Each day increase in stay in the hospital after the surgery increased the risk of contacting an SSI by 5%. Conclusions Incidence and risk factors from prospective SSI surveillance can be reported simultaneously for the Obstetric and Gynecological surgeries and can be part of routine practice in resource-constrained settings. The incidence of SSI was lower for Obstetric surgeries compared to Gynecological surgeries. Multiple risk factors identified in the present study can be helpful for SSI risk stratification in low-middle income countries.

Reliable and efficient medium access control (MAC) protocols are crucial for energy-efficient data communication and effective resource utilization in Wireless Sensor Networks (WSNs). In this work, we propose an Energy-Efficient UAV-assisted Two-Layer Hierarchical (EE-UAV-TLH) MAC protocol, designed for mission-critical applications with energy constraints and limited bandwidth. The protocol employs a two-level hierarchical clustering structure, where sensor nodes communicate with their Cluster Head (CH), and the CH coordinates with an Unmanned Aerial Vehicle (UAV) for data collection and transmission scheduling. By adopting a bit-mapping access scheme, EE-UAV-TLH significantly reduces idle listening and control overheads, while the UAV acts as a mobile sink and synchronization controller, enhancing scalability and minimizing energy usage. Simulation results across diverse scenarios demonstrate that the TLH-ETDMA variant consistently outperforms its counterparts (TLH-TDMA and TLH-BMA), yielding average energy savings of about 20% over TLH-TDMA and 34% over TLH-BMA. In peak cases, EE-UAV-TLH achieves up to 31% improvement against TLH-TDMA and up to 52% against TLH-BMA. Even under large-scale deployment with 110 nodes, it sustains 17% and 39% savings, respectively, highlighting its superior efficiency and scalability for UAV-assisted WSNs.

We synthesize porous polyHIPE networks with silanol functionalities in the polyHIPE backbone. These silanol functionalities are used for covalent bonding with silica aerogels embedded in the polyHIPE. Covalent bonding between silica and polyHIPE networks are confirmed using Fourier-transform infrared spectroscopy and scanning electron microscopy. Silica aerogels covalently bonded with polyHIPE network show macroporous and mesoporous morphologies and possess excellent properties like high bendability, high elasticity, superhydrophobicity (~160°), low density (~0.128 g/cm 3 ), and low thermal conductivity (~0.045 W/m·K). Oil absorption from water/oil mixtures and recovery of the absorbed oil (by squeezing) from flexible silica-polyHIPE networks is studied. The silica-polyHIPE is shown to absorb crude oil ~16-times its own weight and can be reused multiple times after recovery. Hence, such materials are very important for oil spill cleanup applications from aqueous systems.