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Optical coherence tomography (OCT) is a label-free, non-invasive 3D imaging tool widely used in both biological research and clinical diagnosis. Current OCT modalities can only visualize specimen tomography without chemical information. Here, we report a bondselective full-field OCT (BS-FF-OCT), in which a pulsed mid-infrared laser is used to modulate the OCT signal through the photothermal effect, achieving label-free bond-selective 3D sectioned imaging of highly scattering samples. We first demonstrate BS-FF-OCT imaging of 1 {\mu}m PMMA beads embedded in agarose gel. Next, we then show 3D hyperspectral imaging of polypropylene fiber mattress from a standard surgical mask. We then demonstrate BS-FFOCT imaging on biological samples, including cancer cell spheroids and C. elegans. Using an alternative pulse timing configuration, we finally demonstrate the capability of BS-FF-OCT on a bulky and highly scattering 150 {\mu}m thick mouse brain slice.

This study assessed the effects of feed carbohydrate content on intestinal physical barrier and immunity in juvenile largemouth bass (Micropterus salmoides). Triplicate groups of juvenile fish (4.1 ± 0.2 g) were fed low (LCD, 7%), medium (MCD, 12%) and high (HCD, 17%) carbohydrate diets for eight weeks. Gut histology revealed the slight infiltration of inflammatory cells and moderate loss of mucous membrane layer in HCD group. Expression of ZO1, occluding, and claudin7 genes and epidermal growth factor receptor (EGFR) gene were significantly decreased in HCD group indicating the impairment of tight junction and epithelial cell regeneration. The results showed the significant (P 0.05) reduction of antioxidant capacity in HCD group compared to LCD. Furthermore, expression of intestinal ERS-related genes such as IRE1, Eif2α, GRP78, CHOPα and CHOPβ in HCD group was significantly higher than the LCD group. In addition, HCD induced the up-regulated expression of inflammatory (IL-8, IL-1β, TNFα and COX2) and apoptosis (TRAF2, bax, casepase3, caspase8 and casepase9) related genes in fish intestine. The data generated in this study clearly demonstrated that HCD induced ERS and oxidative stress, which promoted intestinal inflammation and apoptosis in juvenile largemouth bass.

Surface-enhanced Raman scattering (SERS) spectroscopy has been used extensively to study biology, chemistry, and materials. However, a point-by-point SERS mapping is time-consuming, taking minutes to hours for large-scale imaging. Here, we report a wide-field surface-enhanced coherent anti-Stokes Raman scattering (WISE-CARS) microscopy for monitoring nanotags in live cells and label-free detection of metabolic molecules. The WISE-CARS microscope achieves an imaging speed as fast as 120 frames per second for a large field of view of 130 microns X 130 microns. By spectral focusing of femtosecond lasers, a hyperspectral WISE-CARS stack of 120 frames can be acquired with a spectral resolution of 10 cm-1, where over 1 million Raman spectra are parallelly recorded within 0.5 seconds. As applications, we demonstrate time-lapse, 3D WISE-CARS imaging of nanotags in live cells as well as label-free detection of adenine released from S. aureus.

Aeromonas salmonicida is a fish pathogen that has resulted in significant losses to the aquaculture industry worldwide. In the winter of 2018/2019, a serious outbreak of A. salmonicida infection of grass carp (Ctenopharyngodon idella) occurred in China. Since C. idella do not feed at low water temperatures, antibiotics cannot be delivered orally, thus the use of disinfectants is the only viable option to control the disease in the winter months. Therefore, the aim of this study was to elucidate the inhibitory effects of different disinfectants against A. salmonicida at various temperatures and pH values. The microdilution method was used to determine the minimum inhibitory concentration (MIC) of five disinfectants against A. salmonicida at different temperatures. The results showed that A. salmonicida was highly adaptable to temperatures ranging from 8 to 35 °C and pH values from 5 to 9. Moreover, based on the results, benzalkonium bromide (BB) had the strongest inhibitory effect at every temperature. Since A. salmonicida has strong environment adaptability, BB should be chosen to control the disease at low temperatures.

Urban space is vital to contemporary urban life. However, the digital era has had an enduring impact on global urban space. The vitality of many physical urban spaces has been declining, with many of their functions replaced by online activities. It has become crucial to theoretically reconsider the key elements of the attractiveness of urban space and to find an effective practical measurement to improve urban space vitality. Therefore, this paper applies an interdisciplinary view of sociology and urban planning, raising an explanatory framework to show that the major determinant of urban space vitality has shifted to “spatial social interaction”, which is derived from people's social needs. Based on this assumption, this paper further presents various factors of spatial social interaction and constructs a quantitative model. In addition, it verifies the model through an empirical analysis of OCT Loft in Shenzhen, China. In the process, the interaction parameters of typical spaces are calculated and compared with the actual situation and shows a positive correlation. The construction of the theoretical framework and preliminary verification are expected to provide insights into the worldwide revitalization of urban space and to help in the preevaluation of related designs.

Heavy metals and polycyclic aromatic hydrocarbons (PAHs) in soil pose great threat to humans and the environment, and should be strictly removed. In the present study, a plant which was suitable for growth in co-contaminated soil was investigated, then co-contaminants removal with increasing contaminants concentrations and bacteria variations in co-contaminatedsoil were studied. Ryegrass (Lolium perenne L.) represented higher germination rate and biomasss than tall fescue (Festuca arundinacea Schreb.), alfalfa (Medicago sativa L.) and white clover (Trifllium repens L.), when cultured on co-contaminated soil with Cd at 16.8 mg/kg and pyrene at 71 mg/kg. Co-contaminants removal was enhanced when pyrene increased from 14 mg/kg to 140 mg/kg, and inhibited when Cd injection increased more than 3.4 mg/kg. The residual pyrene in ryegrass accounted for 0.38% of its removal, indicating that pyrene biodegradation played the major role in phytoremediation rather than plant adsorption and accumulation. Planting ryegrass in co-contaminated soil increased soil bacteria total species and diversity, and changed microbial community. Specifically, the relative abundance of PAHs degrading genera Gemmatimonas, Ohtaekwangia, Luteimonas, Lacibacterium and Steroidobacter increased, which could benefit pyrene removals.

Organic contaminations and heavy metals in soils cause large harm to human and environment, which could be remedied by planting specific plants. The biochars produced by crop straws could provide substantial benefits as a soil amendment. In the present study, biochars based on wheat, corn, soybean, cotton and eggplant straws were produced. The eggplant straws based biochar (ESBC) represented higher Cd and pyrene adsorption capacity than others, which was probably owing to the higher specific surface area and total pore volume, more functional groups and excellent crystallization. And then, ESBC amendment hybrid Ryegrass (Lolium perenne L.) cultivation were investigated to remediate the Cd and pyrene co−contaminated soil. With the leaching amount of 100% (v/w, mL water/g soil) and Cd content of 16.8 mg/kg soil, dosing 3% ESBC (wt%, biochar/soil) could keep 96.2% of the Cd in the 10 cm depth soil layer where the ryegrass root could reach, and it positively help root adsorb contaminations. Compared with the single planting ryegrass, the Cd and pyrene removal efficiencies significantly increased to 22.8% and 76.9% by dosing 3% ESBC, which was mainly related with the increased plant germination of 80% and biomass of 1.29 g after 70 days culture. When the ESBC dosage increased to 5%, more free radicals were injected and the ryegrass germination and biomass decreased to 65% and 0.986 g. Furthermore, when the ESBC was added into the ryegrass culture soil, the proportion of Cd and pyrene degrading bacteria Pseudomonas and Enterobacter significantly increased to 4.46% and 3.85%, which promoted the co−contaminations removal. It is suggested that biochar amendment hybrid ryegrass cultivation would be an effective method to remediate the Cd and pyrene co−contaminated soil.