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Aiming at the problem of poor indoor thermal environment and poor human comfort in temporary office-prefab house. We used the Airpak simulation software is used to simulate the temporary office-prefab house and the office of a conventional building in a construction site in Xi'an, and analyzed the simulation results of the temperature field, velocity field, PMV and PPD. According to the results, the average temperature of the temperature field of the prefabricated house in summer is about 30 ℃, the average value of the PMV field is greater than 1, and the average value of the PPD field is 40%. The average velocity field is less than 0.3 m/s and roughly the same. According to the human comfort index, the temperature of the prefabricated house in summer is greater than the human comfort temperature, and the PMV value and PPD value have a great relationship with the temperature, so their values are also beyond the human comfort range, and the indoor thermal environment of the prefabricated house is poor.

Radiolabeled bombesin analogs are promising probes for cancer imaging of gastrin-releasing peptide receptor (GRPR). In this study, we developed 18F-labeled GRPR agonists and antagonists for positron emission tomography (PET) imaging of prostate cancer. GRPR antagonists ATBBN (D-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-NHCH2CH3) and MATBBN (Gly-Gly-Gly-Arg-Asp-Asn-D-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-NHCH2CH3), and agonists AGBBN (Gln-Trp-Ala-Val-Gly-His-Leu-MetNH2) and MAGBBN (Gly-Gly-Gly-Arg-Asp-Asn-Gln-Trp-Ala-Val-Gly-His-Leu-MetNH2) were radiolabeled with 18F via 4-nitrophenyl 2-18F-fluoropropionate. The in vitro receptor binding, cell uptake, and efflux properties of the radiotracers were studied on PC-3 cells. An in vivo PET study was performed on mice bearing PC-3 tumors. Direct 18F-labeling of known GRPR antagonist ATBBN and agonist AGBBN did not result in good tumor targeting or appropriate pharmacokinetics. Modification was made by introducing a highly hydrophilic linker Gly-Gly-Gly-Arg-Asp-Asn. Higher receptor binding affinity, much higher cell uptake and slower washout were observed for the agonist 18F-FP-MAGBBN over the antagonist 18F-FP-MATBBN. Both tracers showed good tumor/background contrast, with the agonist 18F-FP-MAGBBN having significantly higher tumor uptake than the antagonist 18F-FP-MATBBN (P < 0.01). In conclusion, Gly-Gly-Gly-Arg-Asp-Asn linker significantly improved the pharmacokinetics of the otherwise hydrophobic BBN radiotracers. 18F-labeled BBN peptide agonists may be the probes of choice for prostate cancer imaging due to their relatively high tumor uptake and retention as compared with the antagonist counterparts.