Heat strain in chemical protective clothing in hot-humid environment:Effects of clothing thermal properties

Heat strain experienced by individuals wearing chemical protective clothing(CPC)is severe and dangerous especially in hot-humid environment.The development of material science and interdisciplinary studies including ergonomics,physiology and heat transfer is urgently required for the reduction of heat strain.The aim of this paper was to study the relationship among clothing thermal properties,physiological responses and environmental conditions.Three kinds of CPC were selected.Eight participants wore CPC and walked(4 km/h,two slopes with 5%and 10%)on a treadmill in an environment with(35±0.5)℃ and RH of(60±5)%.Core temperature,mean skin temperature,heart rate,heat storage and tolerance time were recorded and analyzed.Physiological responses were significantly affected by the clothing thermal properties and activity intensity in hot-humid environment.The obtained results can help further development of heat strain model.New materials with lower evaporative resistance and less weight are necessary to release the heat strain in hot-humid environments.

Do predator energy demands or previous exposure influence protection by aposematic coloration of prey？

Growing evidence exists that aposematic and toxic prey may be included in a predator＇s diet when the predator experiences physiological stress. The tree sparrow Passer montanus is known to have a significant portion of aposematic and toxic ladybirds in its natural diet. Here, we present experi- ments testing the attack and eating rate of the tree sparrow toward the invasive aposematic harle- quin ladybird Harmonia axyridis. We wondered whether the sparrow＇s ability to prey on native ladybirds predisposes them to also prey on harlequin ladybirds. We compared the attack and eat- ing rates of tree sparrows of particular age and/or experience classes to test for any changes during ontogeny （hand-reared x young wild-caught xadult wild-caught） and with differing perceived lev- els of physiological stress （summer adult ~ winter adult）. Winter adult tree sparrows commonly at- tacked and ate the offered ladybirds with no evidence of disgust or metabolic difficulties after in- gestion. Naive and wild immature tree sparrows attacked the ladybirds but hesitated to eat them. Adult tree sparrows caught in the summer avoided attacking the ladybirds. These results suggest that tree sparrows are able to cope with chemicals ingested along with the ladybirds. This pre- adaptation enables them to include ladybirds in their diet; though they commonly do this only in times of shortage in insect availability （winter）. Young sparrows showed avoidance toward the chemical protection of the ladybirds.

Robust,flame-retardant and colorful superamphiphobic aramid fabrics for extreme conditions

High-performance superamphiphobic fabrics are very useful in special fields,such as firefighting,rescue,and polar sports.The complicated preparation process,easily damaged surface structure,and high cost drastically limit their commercial application.In this work,we utilized a simple,low-cost superamphiphobic coating to prepare a superamphiphobic aramid fabric(SAF).The excellent repellency to acid/alkali solutions and low boiling point organic solvents has been demonstrated with the contact angle of>150°and>130°,respectively.Additionally,the original color of the fabric can also be maintained,accompanied by superior flame retardancy,strength and comfort with thermal degradation of 361℃.More importantly,SAF displayed excellent durability via 50 standard machine washes,100-min of ultrasonic washing,10-min of UV irradiation,120-min of high-temperature heating,5000 cycles of abrasion,and destructive abrasion by sharp metal.All the results showed the superior performance of our SAF in protective fabrics under extreme environmental conditions.

New C_(21)steroidal glycosides from the roots of Cynanchum stauntonii and their protective effects on hypoxia/reoxygenation induced cardiomyocyte injury

Phytochemical investigations from the roots of Cynanchum stauntonii led to obtain four new C_（21） steroidal glycosides（1–4） and one known compound stauntoside F（5）. Their chemical structures were characterized by sophisticated analyses of IR, HRESI-TOF-MS, 1D, and 2D-NMR data, together with chemical methods, which showed interesting 13,14：14,15-disecopregnane-type skeleton or 14,15-secopregnane-type skeleton C_（21） steroidal glycosides. Among them, compound 1 was determined to be glaucogenin C 3-O-b-D-glucopyranosyl-（1 → 4）-b-D-cymaropyranosyl-（1 → 4）-b-D-digitoxopyranosyl-（1 → 4）-b-D-thevetopyranoside. Compound 2 was characterized to be hirundigenin 3-O-a-L-diginopyranosyl-（1 → 4）-b-D-cymaropyranosyl-（1 → 4）-b-D-digitoxopyranosyl-（1 → 4）-b-D-30-demethyl-thevetopyranoside. Compound 3 was identified to be（14S,16 S,20R）-14,16-14,20-15,20-triepoxy-14,15-secopregn-5-en-3-ol-3-O-a-L-cymaropyranosyl-（1 → 4）-b-D-digitoxopyranosyl-（1 → 4）-b-D-oleandropyranoside.Compound 4 was identified to be（14S,16 S,20R）-14,16-14,20-15,20-triepoxy-14,15-secopregn-5-en-3-ol-3-O-a-L-cymaropyranosyl-（1 → 4）-b-D-cymaropyranosyl-（1 → 4）-b-D-digitoxopyranosyl-（1 → 4）-b-Dthevetopyranoside. Among them, compound 2 was hirundigenin type C21 steroidal glycoside that existed in nature as epimers due to the presence of 14-hemiketal hydroxyl group in its structure. In addition, the anti-inflammatory and cardiomyocyte protective effects of compounds 1–4 were evaluated. We found that they exhibited significant protective effects on hypoxia/reoxygenation induced cardiomyocyte injury, but did not showed obvious anti-inflammatory function.