Chitosan aerogels with potential applications as effective local hemostatic agents were prepared using supercritical carbon dioxide drying to preserve the chitosan network structure featuring high internal surfaces and porosities of up to 300 m²/g and 98%, respectively. For the first time, hemostatic efficacy of chitosan-based aerogel particles was studied in vivo on a model of damage of a large vessel in the deep wound. Pigs were used as test animals. It was shown that primary hemostasis was achieved, there were no signs of rebleeding and aerogel particles were tightly fixed to the walls of the wound canal. A dense clot was formed inside the wound (at the femoral artery), which indicates stable hemostasis. This study demonstrated that chitosan-based aerogel particles have a high sorption capacity and are highly effective as local hemostatic agents which can be used to stop massive bleeding.

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Relevance.Persistent profuse external hemorrhage is known to be one of the main causes of death in combat casualties.Intention.To evaluate experimentally the effectiveness of new chitosan-based topical hemostatic agents (THA) in various models of profuse external arterial hemorrhage.Method.New hemostatic chitosan-based agents of Hemohit type in various pharmaceutical dosage forms (Hemohit powder, 20 g per package and Hemohit-applicator [fine chitosan powder Hemohit-A or chitosan granules Hemohit-AG 6 g in the syringe-applicator]) were assessed for effectiveness in the model of profuse external arterial hemorrhage (bevelled laceration of the femoral artery) in 10 large laboratory animals (pigs). Evaluation of the THA effectiveness was performed according to the following parameters: primary hemostasis – stopping of bleeding immediately after application of the 1st THA package and application of a pressure bandage; secondary haemostasis – stopping bleeding immediately after applying the 2nd THA package and applying a pressure bandage, if the 1st THA package is ineffective; final hemostasis – no bleeding within 3 hours of follow-up; absence / resumption of bleeding after the march test; total amount of blood loss during the experiment; survival.Result and their analysis. It was experimentally found that in the case of external profuse arterial hemorrhage the powder and the syringe-applicator provided permanent hemostasis and 100 % animal survival. In two cases out of four, a second package of Hemohit powder was required for the final stop of bleeding. The bleeding stopped due to the formation of an edge thrombus in the area of the vascular wall defect.Conclusion.Hemohit THA can effectively stop arterial bleeding. The effectiveness of applicator with local hemostats can be assessed in the proposed experimental model with a deep narrow wound canal and femoral artery damage.

<p>Russian lunar program includes several landing missions of Luna-25, Luna-27, Luna-28 which should be implemented step by step to explore mineralogical, chemical, and isotopic compositions of the lunar polar regolith, search for volatile compounds, deliver soil samples to the Earth and prepare future manned expeditions to Moon.</p><p>The successful implementation of these missions requires employing of excavation and drilling of lunar regolith to the different depths with extraction of soil samples for the farther analysis (in situ or sample return).The first mission in row Luna-25 will be launched in October 2021 and landed at the area located north of Boguslawsky crater. This lander is equipped with the Lunar Manipulation Complex (LMC) – the robotic arm that should excavate lunar regolith (down to 5 – 25 cm) and deliver sample of lunar soil to the analytical instrumentation for the elemental and isotopic analysis. The robotic arm is already passed through the validation, functional and calibration tests in lunar-like conditions (low pressures and low temperatures) to imitate interaction with lunar soil simulant enriched with different content of water.</p><p>The Luna – 27 and Luna – 28 will be landed at southern polar regions (landing site selection is in progress). They will be equipped with Deep Drill Systems (DDS) to take samples of polar regolith enriched with water ice and other volatiles from 1-2 m depths. The DDS for Luna-27 , as part of the PROSPECT suit, shall be contributed by ESA. The DDS for Luna – 28 (the sample polar return mission) is being developed by Space Research Institute.In this presentation we report the results of ground tests with LMC units and DDS prototype.In addition to DDS, it is expected that Luna – 28 will carry a small sized lunokhod (~100 kg) to support sample collection and proceed with geological survey program (up to 30 km around the landing site per one year). The lunokhod will study elemental/isotopic/mineral composition of lunar regolith along rover traverse to estimate accessibility of lunar resources (first of all, water ice as a source of hydrogen and oxygen) applicable for potential industry utilization and support of manned expeditions. </p><p>The Russian lunar program assumes synergy of robotic and manned missions. Beyond Luna -25,27,28, it is expected that the next lunar missions will deliver to Moon surface heavy lunokhod, which will prepare the landing of the manned mission.  Finally, as part of testing program for manned lander (without cosmonauts), it is proposed to deliver multifunctional robotic equipment to support  the following arrival of cosmonauts. </p>