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11.
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Joe F. Bozeman III Shauhrat S. Chopra Philip James Sajjad Muhammad Hua Cai Kangkang Tong Maya Carrasquillo Harold Rickenbacker Destenie Nock Weslynne Ashton Oliver Heidrich Sybil Derrible Melissa Bilec 《Journal of Industrial Ecology》2023,27(2):382-394
Now is the time to refocus efforts in urban research and design. A changing climate and extreme weather events are presenting unique challenges to urban systems around the world. These challenges illuminate the social barriers that accompany disruptive events such as resource inequities and injustices. In this perspective, we provide three research priorities for just and sustainable urban systems that help to address these matters. The three research priorities are: (1) social equity and justice, (2) circularity, and (3) digital twins. Conceptual context and future research directions are provided for each. For social equity and justice, the future directions are mandatory equity analysis and inclusionary practices, understanding and reconciling historical injustices, and intentional integration with diverse community stakeholders. For circularity applications, they are better metrics for integration, more robust evaluation frameworks, and dynamic modeling at multiple spatial and temporal scales. Future directions for digital twins include developing principles to reduce complexity, integrating model and system components, and reducing barriers to data access. These research priorities are core to meeting several of the United Nations Sustainable Development Goals (i.e., 1—No Poverty, 8—Decent Work and Economic Growth, 10—Reduced Inequalities, and 11—Sustainable Cities and Communities). Useful social and technical matters are discussed throughout, where we highlight the importance of prioritizing localized research efforts, provide guidance for community-engaged research and co-development practices, and explain how these priorities interact to align with the evolving field of industrial ecology. 相似文献
13.
Mutations in the exon 10 of prolactin receptor gene change the egg production performance in Wanjiang white goose 总被引:1,自引:0,他引:1
To select the molecular genetic markers related to egg performance of Wanjiang white goose, prolactin receptor gene (PRLR)
was adopted to be a candidate gene in our study. Five pairs of primers (P1–P5) were designed to detect the SNPs of PRLR gene
by PCR-SSCP method. The results revealed that polymorphisms were discovered in the PCR products amplified with P4 primers
in PRLR exon 10, three genotypes were found: AA, AB and AC. The sequence of AB genotype is the same as original sequence (DQ660982)
in NCBI. There are five mutations in AA genotype: C → A at 840 bp, C → T at 862 bp, T → C at 875 bp, T → A at 963 bp, A → T
at 989 bp, resulting in amino acid mutations: His → Asn, Thr → Ile, Asn → Lys, Thr → Ser, and synonymous mutation at 875 bp.
Sequencing revealed five mutations in AC genotype: G → T at 816 bp, A → T at 861 bp, C → T at 862 bp, T → C at 875 bp, A → G
at 948 bp, causing amino acid mutations of Val → Phe, Thr → Phe, synonymous mutations at 875 and 963 bp. Besides, there are
an N-glycosylation site (NQSR), three casein kinase II phosphorylation sites including SIIE, SKTE, and SLMD in AA genotype; three
casein kinase II phosphorylation sites including SIIE, SKTE, and TLMD in AB genotype; three casein kinase II phosphorylation
sites including SIFE, SKTE, and TLMD in AC genotype. The annual egg yielding of AB genotype geese are significantly more than
those of AA and AC genotype geese on the average (P < 0.05). It is suggested for the first time that PRLR is a promising candidate gene that can affect egg performance in Wanjiang
white goose. 相似文献
14.
Jia Liu Feng-Yu Liu Zhi-Qian Tong Zhi-Hua Li Wen Chen Wen-Hong Luo Hui Li Hong-Jun Luo Yan Tang Jun-Min Tang Jie Cai Fei-Fei Liao You Wan 《PloS one》2013,8(3)
Background
Bone cancer pain seriously affects the quality of life of cancer patients. Our previous study found that endogenous formaldehyde was produced by cancer cells metastasized into bone marrows and played an important role in bone cancer pain. However, the mechanism of production of this endogenous formaldehyde by metastatic cancer cells was unknown in bone cancer pain rats. Lysine-specific demethylase 1 (LSD1) is one of the major enzymes catalyzing the production of formaldehyde. The expression of LSD1 and the concentration of formaldehyde were up-regulated in many high-risk tumors.Objective
This study aimed to investigate whether LSD1 in metastasized MRMT-1 breast cancer cells in bone marrows participated in the production of endogenous formaldehyde in bone cancer pain rats.Methodology/Principal Findings
Concentration of the endogenous formaldehyde was measured by high performance liquid chromatography (HPLC). Endogenous formaldehyde dramatically increased in cultured MRMT-1 breast cancer cells in vitro, in bone marrows and sera of bone cancer pain rats, in tumor tissues and sera of MRMT-1 subcutaneous vaccination model rats in vivo. Formaldehyde at a concentration as low as the above measured (3 mM) induced pain behaviors in normal rats. The expression of LSD1 which mainly located in nuclei of cancer cells significantly increased in bone marrows of bone cancer pain rats from 14 d to 21 d after inoculation. Furthermore, inhibition of LSD1 decreased the production of formaldehyde in MRMT-1 cells in vitro. Intraperitoneal injection of LSD1 inhibitor pargyline from 3 d to 14 d after inoculation of MRMT-1 cancer cells reduced bone cancer pain behaviors.Conclusion
Our data in the present study, combing our previous report, suggested that in the endogenous formaldehyde-induced pain in bone cancer pain rats, LSD1 in metastasized cancer cells contributed to the production of the endogenous formaldehyde. 相似文献15.
BMP signaling in vascular diseases 总被引:1,自引:0,他引:1
16.
Zhang H Cai J Dong J Zhang D Huang L Xu Z Cen P 《Applied microbiology and biotechnology》2011,92(2):295-303
Poly (β-l-malic acid) (PMLA) is a water-soluble polyester with many attractive properties in chemical industry and medicine development.
However, the low titer of PMLA in the available producer strains limits further industrialization efforts and restricts its
many potential applications. In order to solve this problem, a new strain with the distinguished high productivity of PMLA
was isolated from fresh plants samples. It was characterized as the candidate of Aureobasidium pullulans based on the morphology and phylogenetic analyses of the internal transcribed spacer sequences. After the optimization of
culture conditions, the highest PMLA concentration (62.27 g l−1) could be achieved in the shake flask scale. In addition, the contribution of the carbon flux to exopolysaccharide (EPS)
and PMLA could be regulated by the addition of CaCO3 in the medium. This high-level fermentation process was further scaled up in the 10 l benchtop fermentor with a high PMLA
concentration (57.2 g l−1) and productivity (0.35 g l−1 h−1), which are the highest level in all the literature. Finally, the suitable acid hydrolysis conditions of PMLA were also investigated
with regard to the production of l-malic acid, and the kinetics of PMLA acid hydrolysis was modeled to simulate the whole degradation process. The present work
paved the road to produce this multifunctional biomaterial (PMLA) at industrial scale and promised one alternative method
to produce l-malic acid in the future. 相似文献
17.
18.
C Avignolo P Valente S Cai R Roner A Fulle G Pizzorno F A Bignone 《Biochemical and biophysical research communications》1990,170(1):243-250
The bisulfite catalyzed transamination of cytidine and cytosine has been reported to be single strand specific, but local thermal instabilities of the DNA double helix, coupled with the extreme sensitivity of the Biotin-Avidin revelation methods, allows the random labelling of cytosines in d.s. DNA to detectable levels for those purposes where the overall label can be very low. We have evaluated the use of this reaction to prepare double stranded DNA molecules containing N4-aminoethyl-cytosine (4-aeC). After this step 4-aeC residues can be conjugated to biotinyl-n-hydroxysuccinimide ester yielding biotinylated DNA. This reaction allows the massive production of biotinylated probes. Labelled DNA can serve as molecular weight marker and positive control in Southern-blots. Moreover it can be useful in the study of DNA-protein interaction and in the isolation of d.s. DNA-binding proteins through chromatographic procedures. 相似文献
19.
20.
Jiazhang Lian Shinghua Ding Jin Cai Danping Zhang Zhinan Xu Xiaoning Wang 《Applied microbiology and biotechnology》2009,82(3):463-470
Aquaporin Z (AqpZ), a typical orthodox aquaporin with six transmembrane domains, was expressed as a fusion protein with TrxA
in E. coli in our previous work. In the present study, three fusion partners (DsbA, GST and MBP) were employed to improve the expression
level of this channel protein in E. coli. The result showed that, compared with the expression level of TrxA-AqpZ, five- to 40-fold increase in the productivity of
AqpZ with fusion proteins was achieved by employing these different fusion partners, and MBP was the most efficient fusion
partner to increase the expression level. By using E. coli C43 (DE3)/pMAL-AqpZ, the effects of different expression conditions were investigated systematically to improve the expression
level of MBP-AqpZ in E. coli. The high productivity of MBP-AqpZ (200 mg/l) was achieved under optimized conditions. The present work provides a novel
approach to improve the expression level of membrane proteins in E. coli. 相似文献