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151.
Han Sun Lei Wang Hongyun Nie Zhenjun Diwu Maiqian Nie Bo Zhang 《Biotechnology progress》2021,37(4):e3155
Yield and cost are two major factors limiting the widespread use of rhamnolipids (RLs). In the present study, waste frying oil (WFO) was used as the sole carbon source to produce environmentally friendly RLs by Pseudomonas aeruginosa NY3. The Plackett–Burman design (PBD) and Box–Behnken design (BBD) methods were used to maximize the production yield of RL. The PBD results showed that the concentrations of NaNO3, Na2HPO4, and trace elements were the key factors affecting the yield of RL. Furthermore, the BBD results showed that at NaNO3, Na2HPO4, and trace elements concentrations were 4.95, 0.66, and 0.64 mL/L, respectively, the average RL yield reached 9.15 ± 0.52 g/L, 1.58-fold higher than that observed before optimization. Fourier transform infrared spectroscopy (FTIR) and liquid chromatography-ion trap-time of flight mass spectrometry (LCMS-IT-TOF) were used to elucidate the diversity of RL congeners. The results showed that, after optimization, the RL congener diversity increased, and the major RL constituent was converted from di-RLs (64.04%) to mono-RLs (60.44%). These results suggested that the concentrations of the components contained in the culture medium of P. aeruginosa NY3 influenced not only the yield of RL, but also its congener distribution. 相似文献
152.
153.
当我们和其他生命朝夕相处时,也许会重新思考自己和它们之间的位置与关系。动物园的饲养员就是这样,我们经常会听到他们说:“是动物教育了我。”[编者按] 相似文献
154.
Yupeng Pan Shuping Qu Kailiang Bo Meiling Gao Kristin R. Haider Yiqun Weng 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(7):1531-1548
Key message
QTL analysis revealed 11 QTL underlying flowering time and fruit size variation in the semi-wild Xishuangbanna cucumber, of which, FT6.2 and FS5.2 played the most important roles in determining photoperiod-dependent flowering time and round-fruit shape, respectively.Abstract
Flowering time and fruit size are two important traits in domestication and diversifying selection in cucumber, but their genetic basis is not well understood. Here we reported QTL mapping results on flowering time and fruit size with F2 and F2:3 segregating populations derived from the cross between WI7200, a small fruited, early flowering primitive cultivated cucumber and WI7167, a round-fruited, later flowering semi-wild Xishuangbanna (XIS) cucumber. A linkage map with 267 microsatellite marker loci was developed with 138 F2 plants. Phenotypic data of male and female flowering time, fruit length and diameter and three other traits (mature fruit weight and number, and seedling hypocotyl length) were collected in multiple environments. Three flowering time QTL, FT1.1, FT5.1 and FT6.2 were identified, in which FT6.2 played the most important role in conferring less photoperiod sensitive early flowering during domestication whereas FT1.1 seemed more influential in regulating flowering time within the cultivated cucumber. Eight consensus fruit size QTL distributed in 7 chromosomes were detected, each of which contributed to both longitudinal and radial growth in cucumber fruit development. Among them, FS5.2 on chromosome 5 exhibited the largest effect on the determination of round fruit shape that was characteristic of the WI7167 XIS cucumber. Possible roles of these flowering time and fruit size QTL in domestication of cucumber and crop evolution of the semi-wild XIS cucumber, as well as the genetic basis of round fruit shape in cucumber are discussed.155.
Caroline Sharmilee Josefin Karlsson Sofiia Miliutenko Anna Björklund Ulla Mörtberg Bo Olofsson Susanna Toller 《The International Journal of Life Cycle Assessment》2017,22(8):1302-1317
Purpose
The purpose of the study was to outline and demonstrate a new geographic information system (GIS)-based approach for utilising spatial geological data in three dimensions (i.e. length, width and depth) to improve estimates on earthworks during early stages of road infrastructure planning.Methods
This was undertaken by using three main methodological steps: mass balance calculation, life cycle inventory analysis and spatial mapping of greenhouse gas (GHG) emissions and energy use. The mass balance calculation was undertaken in a GIS environment using two assumptions of geological stratigraphy for two proposed alternative road corridors in Sweden. The estimated volumes of excavated soil, blasted rock and filling material were later multiplied with the GHG emission and energy use factors for these processes, to create spatial data and maps in order to show potential impacts of the studied road corridors. The proposed GIS-based approach was evaluated by comparing with actual values received after one alternative was constructed.Results and discussion
The results showed that the estimate of filling material was the most accurate (about 9 % deviation from actual values), while the estimate for excavated soil and blasted rock resulted in about 38 and 80 % deviation, respectively, from the actual values. It was also found that the total volume of excavated and ripped soils did not change when accounting for stratigraphy.Conclusions
The conclusion of this study was that more information regarding embankment height and actual soil thickness would further improve the model, but the proposed GIS-based approach shows promising results for usage in LCA at an early stage of road infrastructure planning. Thus, by providing better data quality, GIS in combination with LCA can enable planning for a more sustainable transport infrastructure.156.
Bo Xiong Shuang Ye Xia Qiu Ling Liao Guochao Sun Jinyu Luo Lin Dai Yi Rong Zhihui Wang 《Acta Physiologiae Plantarum》2017,39(4):98
The role of exogenous spermidine (Spd) in alleviating fruit granulation in the grafted seedlings of a Citrus cultivar (Huangguogan) was investigated. Granulation resulted in increased electrical conductivity, cell membrane permeability, and total pectin, soluble pectin, cellulose, and lignin contents. However, it decreased the activities of superoxide dismutase, peroxidase, and catalase, as well as the (Spd + Spm):Put ratio. The application of exogenous Spd onto Huangguogan seedlings significantly increased proline and ascorbate contents, but decreased the H2O2 and O 2 ?· levels, which suggested that exogenous Spd provided some protection from oxidative damage. In addition, exogenous Spd decreased cell membrane permeability and MDA content, and increased the (Spd + Spm):Put ratio. The activities of antioxidant enzymes, such as catalase, peroxidase, and superoxide dismutase, were increased in Spd-treated seedlings affected by fruit granulation, resulting in a decrease in oxidative stress levels. The protective effects of Spd were reflected by a decrease in superoxide levels through osmoregulation, increased proline and ascorbate contents, and increased antioxidant activities. Our observations reveal the importance of exogenous Spd in alleviating citrus fruit granulation. 相似文献
157.
Ekblad T Bergström G Ederth T Conlan SL Mutton R Clare AS Wang S Liu Y Zhao Q D'Souza F Donnelly GT Willemsen PR Pettitt ME Callow ME Callow JA Liedberg B 《Biomacromolecules》2008,9(10):2775-2783
This work describes the fabrication, characterization, and biological evaluation of a thin protein-resistant poly(ethylene glycol) (PEG)-based hydrogel coating for antifouling applications. The coating was fabricated by free-radical polymerization on silanized glass and silicon and on polystyrene-covered silicon and gold. The physicochemical properties of the coating were characterized by infrared spectroscopy, ellipsometry, and contact angle measurements. In particular, the chemical stability of the coating in artificial seawater was evaluated over a six-month period. These measurements indicated that the degradation process was slow under the test conditions chosen, with the coating thickness and composition changing only marginally over the period. The settlement behavior of a broad and diverse group of marine and freshwater fouling organisms was evaluated. The tested organisms were barnacle larvae (Balanus amphitrite), algal zoospores (Ulva linza), diatoms (Navicula perminuta), and three bacteria species (Cobetia marina, Marinobacter hydrocarbonoclasticus, and Pseudomonas fluorescens). The biological results showed that the hydrogel coating exhibited excellent antifouling properties with respect to settlement and removal. 相似文献
158.
Eva Persson Margret Wülbers-Mindermann Charlotte Berg Bo Algers 《Acta veterinaria Scandinavica》2008,50(1):24
Background
The natural feeding behaviour of the pig is searching for feed by rooting activities throughout the day; self-feeding pigs randomly space their eating and drinking periods throughout the day consuming ten to twelve meals per day. Pigs in conventional fattening pig production are normally fed 2–3 times daily with the feed consumed within 15 minutes. The aim of this study was to determine if more frequent feedings could improve the performance of conventionally kept fattening pigs. 相似文献159.
Zhang KL Sun Y Li Y Liu M Qu B Cui SH Kong QY Chen XY Li H Liu J 《Translational oncology》2008,1(1):28-35
This study aimed to profile the methylation statuses of CDH1/E-cadherin and five CpG island methylator phenotype (CIMP)-associated genes (p16, hMLH1, MINT1, MINT2, and MINT31) in gastric specimens of 47 Dalian long-term residents with and 31 without gastric cancers (GCs). CIMP patterns were classified as CIMP-H with over three methylated genes, CIMP-L with one to two methylated genes, and CIMP-N without methylation. Of 47 GC cases, 24 (51.1%) were CIMP-H, 18 (38.3%) were CIMP-L, and 5 (10.6%) were CIMP-N, whereas 5 of 21 (23.8%) premalignant lesions were CIMP-H and 15 (71.4%) were CIMP-L. CIMP-L was found in 75% (12/16) of GC-adjacent mucosa and in 38.7% (12/31) of mucosa from GC-free patients. CDH1 methylation occurred in 48.9% (23/47) of cancer, in 23.8% (5/21) of premalignant, and in 25% (4/16) of noncancerous tissues and was correlated with patients' age (P = .01), lymph node metastasis, and CIMP severity (P = .000-.028). Our results demonstrated that the frequencies of CIMP-H in Dalian GCs, CIMP-L, and p16 methylation in GC-adjacent tissues and in GC-free mucosa were much higher than those reported previously, indicating the elevated methylation pressure in this GC high-risk region. The close correlation between CDH1 methylation and CIMP severity suggests the necessity of their combination in GC prevention and earlier diagnosis. 相似文献
160.
Anderson MG Hawes NL Trantow CM Chang B John SW 《Pigment cell & melanoma research》2008,21(5):565-578
Spontaneous mutations altering mouse coat colors have been a classic resource for discovery of numerous molecular pathways. Although often overlooked, the mouse iris is also densely pigmented and easily observed, thus representing a similarly powerful opportunity for studying pigment cell biology. Here, we present an analysis of iris phenotypes among 16 mouse strains with mutations influencing melanosomes. Many of these strains exhibit biologically and medically relevant phenotypes, including pigment dispersion, a common feature of several human ocular diseases. Pigment dispersion was identified in several strains with mutant alleles known to influence melanosomes, including beige, light, and vitiligo. Pigment dispersion was also detected in the recently arising spontaneous coat color variant, nm2798. We have identified the nm2798 mutation as a missense mutation in the Dct gene, an identical re-occurrence of the slaty light mutation. These results suggest that dysregulated events of melanosomes can be potent contributors to the pigment dispersion phenotype. Combined, these findings illustrate the utility of studying iris phenotypes as a means of discovering new pathways, and re-linking old ones, to processes of pigmented cells in health and disease. 相似文献