The Topical Effect of rhGDF-5 Embedded in a Collagen–Gelatin Scaffold for Accelerated Wound Healing

The application of exogenous growth factors such as the recombinant human growth and differentiation factor 5 (rhGDF-5) represents a major research topic with great potential for the treatment of complex wounds. In a randomized, controlled minipig study, the topical effect of rhGDF-5 on full-thickness skin defects was evaluated. A total of 60 deep dermal wounds were either treated with rhGDF-5 embedded in an innovative collagen scaffold or another commonly used collagen matrix or left untreated. Wound healing was analyzed by planimetric analysis to determine wound closure over time. After 21 days, the areas of the initial wounds were excised, and the newly formed tissue was examined histologically. In comparison to untreated wounds, all examined matrices accelerated dermal wound healing. The largest acceleration of wound healing was seen with the high-dose rhGDF-5-treated wounds, which, compared to the untreated wounds, accelerated wound healing by 2.58 days, improved the neoepidermal thickness by 32.40 µm, and increased the epidermal cell density by 44.88 cells. The innovative collagen scaffold delivered rhGDF-5 adequately, served as a template to guide proliferating and restructuring cells, and accelerated wound healing. Thus, this composite product offers a novel tool for developing effective wound dressings in regenerative medicine.

Functional Application for the Corn Leaf Fibre to Make Reinforced Polymer Composites Sheet

This research work has mainly utilized agricultural waste material to make a good-quality composite sheet product of the profitable, pollution free, economical better for farmer and industries. In this study, from corn leaf fibre to reinforced epoxy composite product has been utilized with minimum 35 to maximum range 55% but according to earlier studies, pulp composite material was used in minimum 10 to maximum 27%. Natural fibre-based composites are under intensive study due to their light weight, eco-friendly nature and unique properties. Due to the continuous supply, easy of handling, safety and biodegradability, natural fibre is considered as better alternative in replacing many structural and non-structural components. Corn leaf fibre pulp can be new source of raw material to the industries and can be potential replacement for the expensive and non-renewable synthetic fibre. Corn leaf fibre as the filler material and epoxy as the matrix material were used by changing reinforcement weight fraction. Composites were prepared using hand lay-up techniques by maintaining constant fibre and matrix volume fraction. The sample of the composites thus fabricated was subjected to tensile, impact test for finding the effect of corn husk in different concentrations.

Industrial Re-Use of Composites

The amount of obsolete composites is increasing on a global scale, for example yacht hulls from a growing leisure industry and large rotor blades from wind energy production. Until now it has not been possible to recycle or disassemble thermoset composites into their original constituent parts of fibre reinforcement and resins. Subsequently a new method of re-use has been developed. This method involves machining the obsolete composite product into strips or flakes for re-use as reinforcing elements which, when combined with fresh resin and fibre, enable the production of a brand new component. This, in effect, preserves and re-uses the mechanical properties of the original obsolete composite. This method has been proven in manufacturing retaining walls, also guide beams for canals, crane mats and bridge decking, all using the strips or flakes from end of life composite products. For use on an industrial scale, a positive business case is imperative. In order to prove the industrial technology, new products have to contain a sufficiently high percentage of re-used composites in combination with automated processing. This has been achieved with “push-pultrusion” which is in essence a further development of the long established pultrusion process.

Research of Safe Technology of Impregnation of Heated Reinforcing Materials with Binder

Prepreg manufacturing process is one of the most important preparatory technological processes, quality of which has the decisive influence on the physical, mechanical, processing and operational characteristics of the finished composite product. However, manufacturing of prepregs is associated with a number of harmful factors, negatively affecting the participants in the technological process and the environment. Consequently, significant additional costs are required in order to ensure specified maximum permissible levels and concentrations of the harmful products released by the components of polymeric composite materials in the product manufacturing process. The paper deals with the study of peculiarities and efficiency of impregnation of the heated reinforcing material using solvent-free binder. The method for predicting the optimal process parameters of binder solutions for impregnation of prepregs, taking into account the safety of production activity, has been developed. The problem of thermal conductivity from the heated reinforcing material to the binder, which allowed establishing the law of temperature distribution over the depth of the impregnating bath, depending on the duration of continuous impregnation, has been solved. It is found that the binder, with the duration of impregnation even within one working shift, heats up to the temperatures excluding the formation of centers of exothermic polymerization reaction in it. It indicates the availability of the effective regimes of impregnation using the method under study. The paper proposes the practical ways of improvement of the investigated method of impregnation by varying the wavelength, programmed change of the temperature of the reinforcing material at the entry to the bath, and setting of the optimal coordinates of the binder supply as it is drawn in the process of continuous impregnation of the reinforcing material.

Cross-validation of microwave snowfall products over the continental United States

<p>In this talk, surface snowfall rate estimates from the Global Precipitation Measurement (GPM) mission’s Core Observatory sensors and the CloudSat radar are compared to those from the Multi-Radar Multi-Sensor (MRMS) radar composite product over the continental United States. The analysis spans a period between Nov. 2014 and Sept. 2020 and covers the following products: the Dual-Frequency Precipitation Radar product (2A.GPM.DPR) and its single frequency counterparts (2A.GPM.Ka, 2A.GPM.Ku); GPM Combined Radar Radiometer Algorithm (2B.GPM.DPRGMI.CORRA); the CloudSat Snow Profile product (2C-SNOW-PROFILE) and two passive microwave retrievals i.e. the Goddard PROFiling algorithm (2A.GPM.GMI.GPROF) and the Snow retrievaL ALgorithm fOr gMi (SLALOM). </p><p>The 2C-SNOW product has the highest Heidke Skill Score (HSS=75%) for detecting snowfall among all the analysed products. SLALOM ranks the second (60%) while the Ka-band products falls at the end of the spectrum, with the HSS of 10% only. Low detection capabilities of the DPR products are a result of its low sensitivity. All the GPM retrievals underestimate not only the snow occurances but also snowfall volumes. Underestimation by a factor of two is present for all the GPM products compared to MRMS data. Large discrepancies (RMSE of 0.7 to 1.5 mm/h) between space-borne and ground-based snowfall rate estimates can be attributed to the complexity of ice scattering properties and differences in the algorithms' assumptions.</p>

Investigation of spider web oriented composite fabrics burst strength

<abstract> <p>Burst strength is a significant property that determines all other properties of structures to perform under induced internal pressure. In this study, the burst strength of a spider web-formed fabric structure is experimentally investigated. The spider web form orientation is prepared using Embroidery machine. A spider web develops a self-stressing nature, which offers its excellent inelasticity and provides a mechanism for competent and economical means to harmonize the local and global induced stresses in their structure. The obtained results are compared with published works on different effects of fiber architectures. The burst test result on spider web form indicated a spider web form's potential candidacy to utilize it as a future fiber orientation technique to form an enhanced composite reinforcement. However, fiber orientation influences the fiber-reinforced composite's mechanical properties. Fiber orientation via spider web form has not yet been used as a reinforcing engineering composite product. Hence, conducting rigors experimental work on spider web form reinforced composite structures can be taken as a significant step to fill the research gap.</p> </abstract>

A Relative Radiation Normalization Method of ISS Nighttime Light Images Based on Pseudo Invariant Features

The International Space Station (ISS) offers a unique view from space that provides nighttime light (NTL) images of many parts of the globe. Compared with other NTL remote sensing data, ISS NTL multispectral images taken by astronauts with commercial digital single-lens reflex (DSLR) cameras have the characteristics of free access, high spatial resolution, abundant data and no light saturation, so it plays a unique advantage in the research of small-scale urban planning, optimization of lighting resource allocation and blue light pollution. In order to improve the radiation consistency of ISS NTL images, a relative radiation normalization method of ISS NTL images is proposed in this paper. Pseudo invariant features (PIF) were identified in the cloud-free Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) time series NTL remote sensing annual composite product, and then they were used to derive the relative radiation normalization model of ISS NTL images. The results show that the radiation brightness of ISS NTL images in different regions is normalized to the same gray level with that of DMSP/OLS NTL remote sensing images in the same year, which improves the radiation brightness comparability between different regions of ISS NTL images. This method is universally applicable to all ISS NTL images, which is beneficial to the NTL comparability of ISS NTL image in the regional horizontal and temporal vertical.

Fabrication of Metal Matrix Composites Based on Hydroxyapatite by Self-high Propagating Temperatures Synthesis (SHS)

The use of cow bones for biomaterial is still limited; accordingly, the cow bones waste has low economic value. Basically, a human&rsquo;s and a cow&rsquo;s bones are the same in terms of their forming compound. Aluminum (Al) has the potential to combine with hydroxyapatite (HAp) to make metal matrix composites (MMC) that have the potential for biomaterials. Compatible elements to be combined with Al and HAp are magnesium (Mg), titanium (Ti), and Copper (Cu), used self-high propagating temperatures synthesis (SHS). MMC can be processed to be a useful, solid product. Applying pressure to the SHS reaction and heating process may result in biomaterial composite product consisting of some matrix materials such as Al come from cans materials used in the experiment was HAp that was processed from cow bones calcination, added by can that contained aluminum and wetting agent, namely magnesium. The exothermic temperature was 800-900&deg;C. The compaction process was done to allow materials to be bound. Based on the ASTM F138 standard for element of biomaterials, the porosity value was below 30% and hardness level above 40 HV. Cow bones and can-based composite sample with the composition of HAp-Al-Mg: 85%-10%-5% met the standard since the hardness value was: 73.3 HV with a porosity value of 29.88%.