Measuring the Pattern of High Temperature Areas in Urban Greenery of Nanjing City, China

Most studies are concerned with the cooling effect of urban greenery, but some have also revealed that some patches changed from normal temperature areas (NTAs) into high temperature areas (HTAs). Landsat TM images and ArcGIS software are used to analyze the HTA patterns in Nanjing, China. The HTAs’ lower limit temperature was defined as the 30.26 °C and the percentage of the HTAs in all greenery was 24.87%. The disturbance on the cooling effect existed but not evidently. The average impervious ratio (IR) and surface temperature (ST) of HTAs, respectively, were 3.76 times and higher 2.86 °C than those of NTAs. The structure of NTAs’ IR levels was extremely uneven but the HTAs’ were relatively even. However, the co-coefficient between the IR and ST in the whole greenery was small. Sampling analysis with the same ST and IR revealed that the complex environment in green buffer affected temperature differences; The adjacent HTAs, with its 89.78% in the study area, largely along the green patch, were far more than independent HTAs and presented a ring shape. Thus, the significantly heterogeneous urban environment inevitably resulted in diverse factors forming HTAs

Perfect Solar Absorber with Extremely Low Infrared Emissivity

We propose a multi-materials solar absorber consisting of regularly arranged cross resonators made of Ni, and nanocylinders made of Ti on their four corners. The finite difference time domain (FDTD) method is used to study the absorption performance of solar energy, the inherent absorption mechanisms and influencing factors of the absorber submerged in water. The proposed absorber achieves a nearly perfect absorption in the wavelength range of 300–2400 nm with an average absorptance higher than 98%, indicating that most of solar energy will be harvested. In addition, the high absorptance in the solar spectrum originates from the plasmon resonances of cross resonators and the magnetic polariton from the interaction between cross nanostructures and multi-material nanocylinders. Moreover, our absorbers are insensitive to the polarization of light due to the symmetry of the structures, but sensitive to the incident angle of the light. Most significantly, our absorbers can effectively prevent heat loss via radiation heat transfer by lowering their emissivity in the infrared region. The present study demonstrates a new design strategy for perfect solar absorbers consist of simple nanostructures made from multi-materials, which promise potential applications of solar energy harvesting and solar steam generation for desalination and wastewater treatment

Zebrafish on a Chip: A Novel Platform for Real-Time Monitoring of Drug-Induced Developmental Toxicity

<div><p>Pharmaceutical safety testing requires a cheap, fast and highly efficient platform for real-time evaluation of drug toxicity and secondary effects. In this study, we have developed a microfluidic system for phenotype-based evaluation of toxic and teratogenic effects of drugs using zebrafish (<i>Danio rerio</i>) embryos and larvae as the model organism. The microfluidic chip is composed of two independent functional units, enabling the assessment of zebrafish embryos and larvae. Each unit consists of a fluidic concentration gradient generator and a row of seven culture chambers to accommodate zebrafish. To test the accuracy of this new chip platform, we examined the toxicity and teratogenicity of an anti-asthmatic agent-aminophylline (Apl) on 210 embryos and 210 larvae (10 individuals per chamber). The effect of Apl on zebrafish embryonic development was quantitatively assessed by recording a series of physiological indicators such as heart rate, survival rate, body length and hatch rate. Most importantly, a new index called clonic convulsion rate, combined with mortality was used to evaluate the toxicities of Apl on zebrafish larvae. We found that Apl can induce deformity and cardiovascular toxicity in both zebrafish embryos and larvae. This microdevice is a multiplexed testing apparatus that allows for the examination of indexes beyond toxicity and teratogenicity at the sub-organ and cellular levels and provides a potentially cost-effective and rapid pharmaceutical safety assessment tool.</p></div

The heart rates of treated embryos from 48 to 84 hpf by measuring every 12 hpf, the heart rate of the embryos in chamber 7 is zero at 84 hpf.

<p>The asterisks indicate significant differences from control group (chamber 1) * at <i>p</i><0.05.</p

Apl induced abnormal morphology, developmental retardation, and mortality of zebrafish embryos.

<p>(A) Hatched rate and (B) mortality of zebrafish embryos exposed to gradient Apl every 12 hpf in the microfluidic chip for 96 h. (C) Typical morphological abnormalities of embryos exposed to Apl. Red arrows indicate tail malformation, delayed yolk absorption, pericardial edema, and bent trunk, respectively (from upper left-right to bottom left-right). (D) Mean body length of hatched embryos treated with Apl in the chip compared with the controls (C1) at 72 hpf (n = 6), there are no date at C6 and C7 for the fish are not hatched. The asterisks indicate significant differences from control group (chamber 1) * at <i>p</i><0.05.</p

Embryonic and larvae zebrafish on microfluidic chip.

<p>(A) Schematic of chip for zebrafish assay. The chip includes two independent zones, each with a media inlet, a drug inlet, a gradient generator and seven series of fish tanks (one concentration with three tanks) named C1–C7. Left zone for embryonic toxicity and teratogenicity experiment, the right for larvae fish based drug toxicity evaluation. (B) Photos of the microfluidic chip and micrographs of the embryo and larvae in the chip.</p