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Crude Cordyceps militarispolysaccharides (CMPs) have been proven to be effective in alleviating harmful effects of a long-term high-fat diet (HFD), but there are fewer related studies on identifying the health-regulating abilities of certain subcomponents of CMPs. This study aimed to figure out the main component of CMPs in anti-obesity and to further explore its regulatory effects in vivo. Results showed among three main subcomponents (CMP40, CMP60 and CMP80) of CMPs, the large molecular weight CMP40 (with average molecular weight of more than 100 kDa) has shown superior in vitrohypoglycemic and hypolipidemic capacities. The simultaneous intervention of CMP40 indicated that it could reduce the body weight and white adipose tissue mass/area in the HFD mice. Serum parameters also suggested a decrease in the cholesterol and triglyceride level in the CMP40 group. These results might be due to the down-regulation of lipid synthesis and the up-regulation of lipolysis pathways. Besides, CMP40 could alleviate the inflammatory condition, such as the lower LPS and inflammatory cytokines levels, in the HFD mice in a dose-dependent manner. It could also restore gut health by increasing the SCFAs level, regulating gut microbiota structure, and repairing intestinal tight junction. Results also confirmed safe in CMP40 consumption since there were no side-effects on a high concentration addition of CMP40 (8%) to a regular diet. These findings suggested the promising anti-obesity effect of CMP40 and provided a theoretical basis of its further application in food industry.

Inherent optical properties (IOPs) play a key role in modulating an aquatic light field; they are the core link for remotely sensing water constituents based on ocean color remote sensing. Many semi-analytical algorithms (SAAs) have been developed to obtain IOPs from remote sensing reflectance (R_rs) data; these algorithms require a forward model (FM) to link the IOPs to R_rs. Most currently available SAAs use the FM presented by Gordon et al.[J. Geophys. Res.93, 10909 (1988)JGREA20148-022710.1029/JD093iD09p10909] (G88 hereafter) without knowledge of how other models would impact the retrieval of IOPs from R_rs. This study evaluates the effects of two popular SAAs, namely, the quasi-analytical algorithm (QAA) and the generalized IOP algorithm (GIOP), combined with six different FMs on the retrieval of IOPs from a synthetic data set generated with Hydrolight software. The results indicated that different FMs can have quite different effects on the computed R_rs(λ), and the effects were not uniform across the R_rs spectrum. Of the six FMs tested, G88 and P05 [Appl. Opt.44, 1236 (2005)APOPAI0003-693510.1364/AO.44.001236] produced the best estimates of R_rs(λ) at 350, 440, and 550 nm in both oceanic and coastal sub-datasets; they also were less impacted by changes in the particle phase function. M02 also produced a good estimation of R_rs but only at 440 nm, and L04 performed well only in the oceanic condition. When the two SAAs were combined with the six FMs, in the oceanic condition, QAA and GIOP combined with M02 (QM02 and GM02) provided better quality for the absorption coefficient [a(λ)] at 350, 440, and 550 nm when compared with the SAAs combined with the other models. However, for the retrieval of the particle backscattering coefficient [b_bp(λ)] in the oceanic condition, QAA and GIOP combined with L04 (QL04 and GL04) performed better than the others, and GL04 always provided a better estimation of b_bp(λ) than QL04. In the coastal condition, QAA and GIOP combined with G88 or P05 produced slightly better quality of IOPs compared with the other four FMs. Compared with GIOP in the coastal condition, QAA combined with G88 or P05 always showed better quality of retrieval of a(λ) but weaker quality of retrieval of b_bp(λ).

The transmittance of solar radiation in the oceanic water column plays an important role in heat transfer and photosynthesis, with implications for the global carbon cycle, global circulation, and climate. Globally, the transmittance of solar radiation in the visible domain (∼400–700 nm) (TRVIS) through the water column, which determines the vertical distribution of visible light, has to be based on remote sensing products. There are models centered on chlorophyll‐a (Chl) concentration or Inherent Optical Properties (IOPs) as both can be derived from ocean color measurements. We present evaluations of both schemes with field data from clear oceanic and from coastal waters. Here five models were evaluated: (1) Morel and Antoine (1994) (MA94), (2) Ohlmann and Siegel (2000) (OS00), (3) Murtugudde et al. (2002) (MU02), (4) Manizza et al. (2005) (MA05), and (5) Lee et al. ([Lee, Z., 2005]) (IOPs05), where the first four are Chl‐based and the last one is IOPs‐based, with all inputs derived from remote sensing reflectance. It is found that the best performing model is the IOPs05, with Unbiased Absolute Percent Difference (UAPD) ∼23%, while Chl‐based models show higher uncertainties (UAPD for MA94: ∼54%, OS00: ∼133%, MU02: ∼56%, and MA05: ∼39%). The IOPs‐based model was insensitive to the type of water, allowing it to be applied in most marine environments; whereas some of the Chl‐based models (MU02 and MA05) show much higher sensitivities in coastal turbid waters (higher Chl waters). These results highlight the applicablity of using IOPs products for such applications. The vertical distribution of solar radiation in the visible domain estimated from models using remote sensing data as input is evaluatedThe best performance was provided by a scheme centered on the Inherent Optical Properties (IOPs)The mean uncertainty of the estimated transmittance for a range of 0.1–100% is ∼23% from the IOPs system and insensitive to water types

The diffuse attenuation of downwelling irradiance, Kd(m−1), is an important property related to light penetration and availability in aquatic ecosystems. The standard Kd(490) product (the diffuse attenuation coefficient at 490 nm) of the global oceans from satellite remote sensing has been produced with an empirical algorithm, which limits its reliability and applicability in coastal regions. More importantly, as an apparent optical property (AOP), Kdis a function of the angular distribution of the light field (e.g., solar zenith angle). The empirically derived product thus contains ambiguities when compared with in situ measurements as there is no specification regarding the corresponding solar zenith angle associated with this Kd(490) product. To overcome these shortcomings, we refined the Kdproduct with a product termed as the normalized diffuse attenuation coefficient (nKd, m−1), that is equivalent to the Kdin the absence of the atmosphere and with the sun at zenith. Models were developed to get nKdfrom both in situ measurements and ocean color remote sensing. Evaluations using field measurements indicated that the semianalytically derived nKdproduct will not only remove the ambiguities when comparing Kdvalues of different light fields but will also improve the quality of such a product, therefore maximizing the value offered by satellite ocean color remote sensing.

Usable solar radiation (USR) represents spectrally integrated solar energy in the spectral range of 400–560 nm, a domain where photons penetrate the most in oceanic waters and thus contribute to photosynthesis and heating at deeper depths. Through purely numerical simulations, it was found that the diffuse attenuation coefficient of downwelling USR (Kd(USR), m−1) is nearly a constant vertically in the upper water column for clear waters and most turbid waters. Subsequently an empirical model was developed to estimate Kd(USR) based on the diffuse attenuation coefficient at 490 nm (Kd(490), m−1). We here evaluate this relationship using data collected from a wide range of oceanic and coastal environments and found that the relationship between Kd(490) and Kd(USR) developed via the numerical simulation is quite robust. We further refined this relationship to extend the applicability to “clearest” natural waters. This refined relationship was then used to produce sample distribution of Kd(USR) of global oceans. As expected, extremely low Kd(USR) (∼0.02 m−1) was observed in ocean gyres, while significantly higher Kd(USR) (∼5.2 m−1) was found in very turbid coastal regions. A useful application of Kd(USR) is to easily and accurately propagate surface USR to deeper depths, potentially to significantly improve the estimation of basin scale primary production and heat fluxes in the upper water column. Using field measurements, the vertical variability of Kd(USR) is evaluatedRelationship between Kd(USR) and Kd(490) is refined to extend its applicabilityDistribution of Kd(USR) of global oceans and its implications are shown

Using a data set of 1333 samples, we assess the spectral absorption relationships of different wave bands for phytoplankton (ph) and particles. We find that a nonlinear model (second-order quadratic equations) delivers good performance in describing their spectral characteristics. Based on these spectral relationships, we develop a method for partitioning the total absorption coefficient into the contributions attributable to phytoplankton [a_ph(λ)], colored dissolved organic material [CDOM; a_CDOM(λ)], and nonalgal particles [NAP; a_NAP(λ)]. This method is validated using a data set that contains 550 simultaneous measurements of phytoplankton, CDOM, and NAP from the NASA bio-Optical Marine Algorithm Dataset. We find that our method is highly efficient and robust, with significant accuracy: the relative root-mean-square errors (RMSEs) are 25.96%, 38.30%, and 19.96% for a_ph(443), a_CDOM(443), and the CDOM exponential slope, respectively. The performance is still satisfactory when the method is applied to water samples from the northern South China Sea as a regional case. The computed and measured absorption coefficients (167 samples) agree well with the RMSEs, i.e., 18.50%, 32.82%, and 10.21% for a_ph(443), a_CDOM(443), and the CDOM exponential slope, respectively. Finally, the partitioning method is applied directly to an independent data set (1160 samples) derived from the Bermuda Bio-Optics Project that contains relatively low absorption values, and we also obtain good inversion accuracy [RMSEs of 32.37%, 32.57%, and 11.52% for a_ph(443), a_CDOM(443), and the CDOM exponential slope, respectively]. Our results indicate that this partitioning method delivers satisfactory performance for the retrieval of a_ph, a_CDOM, and a_NAP. Therefore, this may be a useful tool for extracting absorption coefficients from in situ measurements or remotely sensed ocean-color data.

The motility ability of intestinal lipopolysaccharide (LPS)-producing bacteria determines their translocation to the enterohepatic circulation and works as an infectious complication. In this study, the health effects of Cordyceps militarispolysaccharides (CMPs) were re-evaluated based on whether these polysaccharides could affect the motility of gut commensal LPS-producing bacteria and impede their translocation. The results showed that CMP-m fermentation in the gut could change the chemical environment, leading to a decrease in velocity and a shift in the motility pattern. Further study suggested that detachment/fragmentation of flagella, decreased motor forces, and changed chemical conditions might account for this weakened motility. The adhesion and invasion abilities of gut bacteria were also reduced, with lower expression of virulence-related genes. These results indicated that the health regulation effects of CMP-m might be through decreasing the motility of LPS-producing bacteria, hindering their translocation and therefore reducing the LPS level in the enterohepatic circulation.