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Lakes influence the regional atmosphere through modifying thermodynamic characteristics. This study examines the effects of the Baikal lake on meteorological parameters in summertime using the numerical model. Diurnal variations in the lakes’ impact on the atmosphere are found through changing the surface energy budget, which includes changes in sensible and latent heat fluxes. The changes in heat fluxes cause relatively lower surface temperature which leads to a shallow boundary layer over the lake surfaces. Greater heat capacity in water bodies compared to grasslands causes slower heating and cooling rates in the lakes. The amplitude of air temperature over the lake surfaces is smaller than that over the grasslands. Lakes promote diverging winds near the ground, furthermore, tend to stabilize the overlying atmosphere in the summertime.

Older adults with sarcopenia, which is an aging-related phenomenon of muscle mass loss, usually suffer from decreases in both strength and functional performance. However, the causality between function loss and physiological changes is unclear. This study aimed to explore the motor unit characteristics of the neurological factors between normal subjects and those with sarcopenia. Five risk-sarcopenia (age: 66.20 ± 4.44), five healthy (age: 69.00 ± 2.35), and twelve young (age: 21.33 ± 1.15) participants were selected. Each participant performed knee extension exercises at a 50% level of maximal voluntary isometric contraction. Next, electromyogram (EMG) signals were collected, and information on each parameter—e.g., motor unit number, recruitment threshold, the slope of the mean firing rate to recruitment threshold, y-intercept, firing rate per unit force, and mean motor unit firing rate (MFR)—was extracted to analyze muscle fiber discrimination (MFD). Meanwhile, force variance was used to observe the stability between two muscle groups. The results suggested that there was no difference between the three groups for motor unit number, recruitment threshold, y-intercept, mean firing rate, and motor unit discrimination (p &gt, 0.05). However, the slope of MFR and firing rate per unit force in the risk-sarcopenia group were significantly higher than in the young group (p &lt, 0.05). Regarding muscle performance, the force variance in the non-sarcopenia group was significantly higher than the young group (p &lt, 0.05), while the risk-sarcopenia group showed a higher trend than the young group. This study demonstrated some neuromuscular characters between sarcopenia and healthy elderly and young people when performing the same level of leg exercise tasks. This difference may provide some hints for discovering aging-related strength and function loss. Future studies should consider combining the in vivo measurement of muscle fiber type to clarify whether this EMG difference is related to the loss of muscle strength or mass before recruiting symptomatic elderly participants for further investigation.

Keratin, a fibrous protein, that is available from a variety of animal sources as a constituent of hair, nails, horns, hoofs, wool and feathers, has applications in pharmaceutics, cosmetics and as a fertilizer. Like many naturally-derived biomaterials, the intrinsic biological activity and biocompatibility of keratin render this polymer a potential candidate for applications in medicine, and for the fabrication of scaffolds for tissue engineering. While several sources of keratin can be considered, the bioactivity of the keratins obtained can be quite different. In this study we discuss the processing and characterization of keratin from camel hair and goat cashmere. Specifically, the camel hair and cashmere were dissolved in an ionic liquid (1-butyl-3-methylimidazolium chloride), and the characteristics of the soluble and insoluble keratin were evaluated. The structure and properties of the raw material, soluble, and insoluble keratin were studied. Compared to the starting material, the soluble keratin showed chemical changes viz. decrease of cysteine, and minor structural changes. Preliminary in vitro biological properties performed by a lactate dehydrogenase (LDH) assay and scratch test showed good bioactivity in keratin from both sources. In particular, cell migration was observed to be faster when cells were cultured in the presence of soluble keratin extracted from camel hair and cashmere.

Developing countries often have difficulties in the field of medicine, and many of these problems do not relate to missing knowledge but on the transportation possibilities to bring patient, doctor and the necessary medical supplies together. In a research study for the country of Mongolia the advantages of a drone delivery system are shown and the unique challenges such as temperature, elevation and range are discussed to choose a suitable system design for countries with enormous size and low population. Airplane like drones with their wider distances seem to be the most promising solution to connect rural areas to the medical logistics network., Embedded Selforganising Systems, Vol 5 No 1 (2018): Unmanned Aerial Systems and Its Application

The development of heterotopic ossification (HO) is considered one of the major complications following cervical total disc replacement (TDR). Even though previous studies have identified clinical and biomechanical conditions that may stimulate HO, the mechanism of HO formation has not been fully elucidated. The objective of this study is to investigate whether mechanical loading is a biomechanical condition that plays a substantial role to decide the HO formation. A finite element model of TDR on the C5-C6 was developed, and HO formation was predicted by simulating a bone adaptation process under various physiological mechanical loadings. The distributions of strain energy on vertebrae were assessed after HO formation. For the compressive force, most of the HO formation occurred on the vertebral endplates uncovered by the implant footplate which was similar to the Type 1 HO. For the anteriorly directed shear force, the HO was predominantly formed in the anterior parts of both the upper and lower vertebrae as the Type 2 HO. For both the flexion and extension moments, the HO shapes were similar to those for the shear force. The total strain energy was reduced after HO formation for all loading conditions. Two distinct types of HO were predicted based on mechanically induced bone adaptation processes, and our findings were consistent with those of previous clinical studies. HO formation might have a role in compensating for the non-uniform strain energy distribution which is one of the mechanical parameters related to the bone remodeling after cervical TDR.

The development of a biomaterial substitute that can promote bone regeneration in massive defects has remained as a significant clinical challenge even using bone marrow cells or growth factors. Without an active, thriving cell population present throughout and stable anchored to the construct, exceptional bone regeneration does not occur. An engineered micro-channel structures scaffold within each trabecular has been designed to overcome some current limitations involving the cultivation and habitation of cells in large, volumetric scaffolds to repair massive skeletal defect. We created a scaffold with a superior fluid retention capacity that also may absorb bone marrow cells and provide growth factor-containing body fluids such as blood clots and/or serum under physiological conditions. The scaffold is composed of 3 basic structures (1) porous trabecular network (300-400 μm) similar to that of human trabecular bones, (2) micro-size channels (25-70 μm) within each trabecular septum which mimic intra-osseous channels such as Haversian canals and Volkmann's canals with body fluid access, diffusion, nutritional supply and gas exchange, and (3) nano-size pores (100-400 nm) on the surface of each septum that allow immobilized cells to anchor. Combinatorial effects of these internal structures result in a host-adapting construct that enhances cell retention and habitation throughout the 3 cm-height and 4 cm-length bridge-shaped scaffold.

Heterotopic ossification is one of the possible complications following cervical total disk replacement. Although there are numerous hypotheses regarding the etiology of heterotopic ossification, the main causes of heterotopic ossification remain unknown. In this study, we hypothesize that heterotopic ossification formation is related to external loading in the cervical vertebrae after total disk replacement. A two-dimensional finite element model of a cervical vertebra treated by total disk replacement in the sagittal plane was developed. The bone adaptation process of heterotopic ossification was simulated based on strain energy density under both compressive and shear forces. Different types of heterotopic ossification formation were analyzed according to the directions of forces. Two distinct types of heterotopic ossification following cervical total disk replacement were predicted, which was consistent with previous clinical studies. Type 1 heterotopic ossification was observed in the posterior upper part of the vertebra under compressive forces, while type 2 heterotopic ossification was detected mostly in the anterior upper part under shear forces. In addition, heterotopic ossification formation enhanced the strain energy distribution, which is known to be related to bone remodeling. This article presents the effects of different mechanical loading conditions on the occurrence of heterotopic ossification following cervical total disk replacement, and the results may be useful for the design of artificial disks that minimize heterotopic ossification.

We have developed a hydroxyapatite-based scaffold with micro-channels and nano-pores (MCNP) using a polyurethane template coating method to overcome some of the limitations by addressing fluid absorbance and retention via capillary action. The novel scaffold has 3 basic structures. First, the scaffold has a porous trabecular network similar to that of human trabecular bones (300–400 um) which are mechanically matched to the strength of native trabecular bone (2–12 MPa). Second, it has micro-sized channels (25–70 um) within each trabecular septum which exhibit highly effective fluid absorption via capillary action. Third, the surface of each septum has nano-sized pores (100–400 nm) that allow immobilized cells to anchor. The surface area of the scaffold with micro-channels was significantly (+42.0%) higher than the scaffold without micro-channels as calculated using computer aided design (CAD) software, while overall porosity did not change significantly (+8.8%). Combinatorial effects of these internal structures result in a host-adapting construct that enhances cell ingress and retention from the host bone marrow throughout the entire scaffold.