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Summary:. “On Arrival Block,” wherein a brachial block is given to a severely injured upper extremity as the first step of the management protocol in the main operating room, bypassing the emergency department, has been found to be a “game changer” in trauma care. Immediate pain relief on arrival builds confidence in the system, allows pain-free initial examination, facilitates use of tourniquet if there are major bleeding wounds, and allows us to obtain good radiographs without an overlap of bones, which usually happens when the radiographs are taken within a bandage. Using the “On Arrival Block” system, emergency room assessment and resuscitation is bypassed. The patient is resuscitated only once, instead of twice. This avoids much duplication of effort, wasted time, patient suffering, unnecessary costs, and mistakes generated by miscommunication between 2 resuscitation teams. This can be done only in the place where all the resuscitative equipment and drugs are available. A senior anesthesiologist and surgeon must be available. The only contraindication is the suspicion of a brachial plexus injury, which can cause the local anesthetic to seep in through the open dural sleeve and cause total spinal anesthesia. “On Arrival Block” was set up at Ganga Hospital, Coimbatore, India, during the early 90s by the anesthesiologist Ravindra Bhat and the plastic surgeon Raja Sabapathy out of necessity, who recognized its value and made it the standard of care.

Recent advancements in catalytic micromotors have shown significant potential for environmental applications, yet challenges such as particle agglomeration persist. In this study, we compare the degradation of methylene blue using hematite particles fully coated with platinum and those partially decorated with platinum. The selective decoration, confirmed through techniques like EDX, FESEM, TEM, and XPS, plays a crucial role in the micromotors' behavior. The decomposition of hydrogen peroxide (H2O2) by Pt nanoparticles on one side of the hematite particles generates thrust, propelling the micromotors and enhancing their interaction with pollutant molecules. This active mobility helps counteract agglomeration, preventing the formation of irregular 3D clusters and improving catalytic efficiency. Our findings show that partially decorated particles achieve up to 85% dye removal within 90 min, outperforming fully decorated particles, which reach only 33% efficiency due to aggregation and sedimentation. These results underscore the importance of optimized surface decoration for improving the performance and stability of catalytic systems in pollutant degradation., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

Microplastics (MPs) are pervasive contaminants that pose significant ecological and human health risks, emerging as one of the most widespread anthropogenic pollutants in natural environments. This study investigates the abundance, characteristics, and distribution of microplastics (MPs) in the Yamuna River, encompassing 29 sampling points across urban, rural, and industrial zones in and around Delhi, Mathura, Haryana, and Agra. Microplastics were identified and quantified using Nile red dye staining and Micro-Raman spectroscopy, with particle size distribution predominantly between 2 μm to 80 μm and the largest detected particle measuring 256.5 μm. The average MPs concentration was 14,717 ± 4444 L -1 , with a significant abundance of hazardous polymers such as polyethylene terephthalate (PET), polypropylene (PP), and polystyrene (PS). The study found that MPs were predominantly fragments and films (65.6 %) and fibers (30.6 %), with transparent particles being the most prevalent. The Pollution Load Index (PLI) consistently indicated high-risk levels (PLI > 100) at all sampling sites, highlighting substantial MP contamination. These results underscore the urgent need for continuous monitoring and the development of robust management strategies to address microplastic pollution in the Yamuna River. This study provides valuable insights into MPs spatial distribution and persistence, contributing to an improved understanding of their environmental impacts and guiding future mitigation and regulatory efforts., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Vijay A. Loganathan reports financial support was provided by India Ministry of Science & Technology Department of Science and Technology. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

We exploit the aggregation between oppositely charged particles to visualize and quantify the equilibrium position of charged colloidal particles at the fluid-water interface. A dispersion of commercially available charge-stabilized nanoparticles was used as the aqueous phase to create oil-water and air-water interfaces. The colloidal particles whose charge was opposite that of the nanoparticles in the aqueous phase were deposited at the chosen fluid-water interface. Heteroaggregation, i.e., aggregation between oppositely charged particles, leads to the deposition of nanoparticles onto the larger particle located at the interface; however, this only occurs on the surface of the particle in contact with the aqueous phase. This selective deposition of nanoparticles on the surfaces of the particles exposed to water enables the distinct visualization of the circular three-phase contact line around the particles positioned at the fluid-water interface. Since the electrostatic association between the nanoparticles and the colloids at interfaces is strong, the nanoparticle assembly on the larger particles is preserved even after being transferred to solid substrates via dip-coating. This facilitates the easy visualization of the contact line by electron microscopy and the determination of the equilibrium contact angle of colloidal particles (θ) at the fluid-water interface. The suitability of the method is demonstrated by the measurement of the three-phase contact angle of positively and negatively charged polystyrene particles located at fluid-water interfaces by considering particles with sizes varying from 220 nm to 8.71 μm. The study highlights the effect of the size ratio between the nanoparticles in the aqueous phase and the colloidal particles on the accuracy of the measurement of θ.

We demonstrate a novel yet straightforward methodology of stabilizing aqueous two-phase systems (ATPS) using oppositely charged nanoparticles (OCNPs). We employ commercial-grade, Ludox, OCNPs to induce self-assembly. This self-assembly route promotes the stronger adsorption of nanoparticles at the water-water interface by triggering the formation of 2D and 3D aggregates of varying sizes and shapes. The interplay of this size and shape promotes stability due to increased Gibbs detachment energy and modulates the resulting cluster adsorption at the interface, thereby the structural state of emulsions. We demonstrate the influence of polymers' and particles' composition on the structural transformation from droplet-bijel-droplet using a phase diagram. For the first time, such a structural transition and the single pathway are reported within the domain of ATPS to produce stable bijels or colloidal capsules. It is asserted that the essential condition of three-phase contact angle (θ) = 90° to favor the formation of bijels can be established by selecting a suitable experimental condition using a phase diagram without employing any complicated surface modification procedures reported in the literature. Further, the mechanistic route favoring the formation of bijels and emulsion droplets at different experimental regimes is presented based on the empirical study using turbidity and zeta potential measurements. These studies reveal that the formation of bijels will be most favored when the parameter M (ratio of weight fraction of positively charged nanoparticles to negatively charged nanoparticles) is chosen between 0.7 and 4. It is intriguing to note the fact that, while the droplets stabilized by OCNPs have shown good resilience under high centrifugal action, the bijels produced in this way continued to remain stable for a long time, offering a facile route to prepare the bijels with a hierarchical bicontinuous network structure.

This study investigated the influence of heat pre-conditioning on the recovery of muscle torque, microvascular function, movement economy and stride mechanics following exercise-induced muscle damage (EIMD). Twenty male participants were equally assigned to a control (CON) and an experimental group (HEAT), and performed a 30-min downhill run (DHR) to elicit EIMD. HEAT group received three consecutive days of heat exposure (45.1 ​± ​3.2 ​min of hot water immersion at 42 ​°C) prior to DHR. Microvascular function (near-infrared spectroscopy), maximal voluntary contraction (MVC) torque of the knee extensors, as well as two treadmill-based steady-state runs performed below (SSR-1) and above (SSR-2) the first ventilatory threshold were assessed prior to DHR and repeated for four consecutive days post-DHR (D1-POST to D4-POST). The decline in MVC torque following EIMD was attenuated in HEAT compared with CON at D1-POST (p ​= ​0.037), D3-POST (p ​= ​0.002) and D4-POST (p ​= ​0.022). Muscle soreness increased in both CON and HEAT, but was significantly attenuated in HEAT compared with CON at D2-POST (p ​= ​0.024) and D3-POST (p ​= ​0.013). Microvascular function decreased in CON from D1-POST to D3-POST (p ​= ​0.009 to 0.018), and was lower compared with HEAT throughout D1-POST to D3-POST (p ​= ​0.003 to 0.017). Pre-heat treatment decreased the magnitude of strength loss and muscle soreness, as well as attenuated the decline in microvascular function following EIMD. Heat treatment appears a promising pre-conditioning strategy when embarking on intensified training periods or competition., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Authors.)

Linear assembly of colloidal particles is of fundamental interest in visualizing polymer dynamics and living organisms. We have developed a fluid-fluid interface-based method to synthesize spherical-cap polymeric latex particles. These particles are shown to spontaneously self-assemble in zigzag arrangement. The linear assembly is induced due to the shape anisotropy (one side is curved and the other side is nearly flat) and heterogeneous charge distribution on the particle surfaces. The necessities of these conditions are justified within the framework of DLVO theory. Spherical-cap particles of various size and aspect ratio reproduced the observed linear assembly, thus demonstrating the robustness of the self-assembly mechanism. While these types of assemblies are observed in spherical particles using microfluidic devices or electric field, the proposed approach is rather facile and does not require any external field. These novel assemblies could be potentially useful to understand kinetics of nucleation and growth of amyloidogenic proteins and to prepare artificial swimming microorganisms.

We report a simple and scalable technique for the preparation of patchy particles with tunable patch coverage. These particles are categorized as inverse patchy colloidal particles (IPCs) as the patches repel each other while patch and non-patch surfaces attract. We demonstrate the effect of patch coverage, concentration of electrolyte and concentration of particles on the self-assembly of IPC particles. The study identifies various clustering zones such as (1) finite-sized clusters, (2) chain-like assemblies and (3) irregular amorphous aggregates. The linear assemblies are observed over a wide range of particle concentrations and salt concentrations. The anisotropic electrostatic interaction controls the formation of chain-like assemblies. In an extended study, we use negatively charged isotropic colloidal (NCIC) particles to tune the self-assembly of IPC particles. Interestingly, we observe significant improvement in the clustering efficiency of IPC particles leading to the formation of co-polymeric, flexible branched chains. Depending on the number ratio of NCIC particles with respect to IPC particles, the clustering process is classified into three different phases such as (1) finite-sized, (2) linear and (3) dispersed state. Using a quantitative analysis we show that such evolution of structures is attributed to seeding and crowding effects caused by the addition of NCIC particles. The use of NCIC particles thus control the self-assembly of inverse patchy colloids and tune the number and shape of the self-assembled structures.

Non-spherical patchy particles are potential candidates as building blocks for the design of target colloidal structures via spontaneous self-organization. We report a facile scheme to synthesize non-spherical particles with patchy electrostatic interactions. In this method, charged spherical latex particles such as polystyrene (PS) are deformed unequally at an oil-water interface due to heating and partial swelling. The spherical particles then evolve into non-spherical shapes such as 'acorn-like' and 'idly-like'. We explain the mechanism of differential deformation by comparing the heat of viscous dissipation and the interfacial energies. Furthermore, if oppositely charged additives such as the cetyltrimethylammonium bromide (CTAB) surfactant or silica nanoparticles are present in water (subphase), electrostatic attraction leads to adsorption of these species on the PS surface exposed to water. As a result, one side of the particles is selectively functionalized, while the other side remains unaltered. As the latex particles are negatively charged initially, this method yields particles that are non-spherical in shape and with negative charges on one side and positive charges on the other side. The degree of shape deformation and patch coverage can be varied by choosing different surface active additives. We extend this approach to curved interfaces and demonstrate a high throughput emulsion based approach for the synthesis of such particles. Self-assembly of these particles shows interesting structures such as linear, branched polymeric or worm-like chains and micelle-like spherical aggregates. These shape anisotropic particles with orientation specific interactions that mimic bio-macromolecular systems can be further explored for self-assembly into hierarchical mesoscale structures.

We present a general yet simple method to measure the contact angle of colloidal particles at fluid-water interfaces. In this method, the particles are spread at the required fluid-water interface as a monolayer. In the water phase a chemical reaction involving reduction of a metal salt such as aurochloric acid is initiated. The metal grows as a thin film or islands of nanoparticles on the particle surface exposed to the water side of the interface. Analyzing the images of particles by high resolution scanning microscopy (HRSEM), we trace the three phase contact line up to which deposition of the metal film occurs. From geometrical relations, the three phase contact angle is then calculated. We report the measurements of the contact angle of silica and polystyrene (PS) particles at different interfaces such as air-water, decane-water and octanol-water. We have also applied this method to measure the contact angle of surfactant treated polystyrene particles at the air-water interface, and we find a non-monotonic change of the contact angle with the concentration of the surfactant. Our results are compared with the well-known gel trapping technique and we find good comparison with previous measurements.

We report a simple strategy to produce single and multipatch particles via the conventional dip-coating process. In this method, a close-packed monolayer of micron-sized silica particles is first formed at air-polymer solution interface, followed by dip coating of particles on a glass substrate. The simultaneous deposition of both polymer and particles on the substrate gives rise to a thin polymer layer and a monolayer of silica particles. Sonication of the substrate leads to the formation of a polymeric patch on one side of the particles. The patch shape depends on the aging of the polymer film prior to sonication. With aging time the patch evolves from ring-like to disk-like. This technique allows easy control of patch width by varying the concentration of polymer in the solution. We further show that the number of patches on the particle can be increased by controlling the concentration of silica particles at the interface such that surface coverage is less than that required for the formation of a close-packed monolayer. The single and multipatch particles are characterized by scanning electron and optical microscopy for the patch size, shape, and number distribution. The as-synthesized particles are used as a model to study self-assembly of colloids with electrostatic repulsion and patchy hydrophobic attractions due to polymeric patches. We find the formation of doublets and finite-sized clusters due to patchy interactions. Dip coating can be automated to produce large quantities of patchy particles, which is one of the major limitations of other methods of producing patchy particles.