We propose a method to consistently estimate production functions in the presence of input price dispersion when intermediate input quantities are not observed. The traditional approach to dealing with unobserved input quantities-using deflated expenditure as a proxy-requires strong assumptions for consistency. Instead, we control for heterogeneous input prices by exploiting the first order conditions of the firm's profit maximization problem. Our approach applies to a wide class of production functions and can be extended to accommodate a variety of heterogeneous intermediate input types. A Monte Carlo study illustrates that the omitted price bias is significant in the traditional approach, while our method consistently recovers the production function parameters. We apply our method to a firm-level data set from Colombian manufacturing industries. The empirical results are consistent with the prediction that the use of expenditure as a proxy for quantities biases the elasticity of substitution downward. Moreover, using our preferred method, we provide evidence of significant input price dispersion and even wider productivity dispersion than is estimated using proxy methods.

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Gut microbiota dysbiosis, associated with insulin resistance, weak intestinal barrier integrity, and inflammation, may also play a role in the development of dietary-induced nonalcoholic fatty liver disease (NAFLD). This study investigates the effects of dietary Lactobacillus plantarum NA136 administration on gut microbiota composition in an insulin-resistant C57BL/6J mouse NAFLD model. Comparison of mice with and without L. plantarum NA136 treatment revealed that L. plantarum NA136 treatment not only relieved insulin resistance but also significantly increased relative proportions of Desulfovibrio, Alistipes, Prevotella, and Enterorhabdus in gut microbiota of NAFLD mice. Meanwhile, L. plantarum NA136 administration also inhibited pathogenic bacterial growth, while promoting growth of probiotics such as Allobaculum, Lactobacillus, and, most markedly, Bifidobacterium. Moreover, L. plantarum NA136 treatment of NAFLD mice improved intestinal barrier integrity and attenuated high-fat and fructose diet (HFD/F)-induced inflammation. These results implicate gut-liver-axis-dependent microbiota modulation as the underlying mechanism for L. plantarum NA136-induced amelioration of NAFLD. Key points • L. plantarum NA136 corrects gut microbiota disorders caused by a high-fat and fructose diet.• L. plantarum NA136 strengthens the intestinal barrier and reduces inflammation in the liver.• L. plantarum NA136 relieves NAFLD by improving the gut-liver axis.

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As a result of the unique geographical characteristics, pastoral lifestyle, and economic conditions in Mongolia, its fragile natural ecosystems are highly sensitive to climate change and human activities. The normalized difference vegetation index (NDVI) was employed in this study as an indicator of the growth status of vegetation. The Sen's slope, Mann-Kendall test, and geographical detector modelling methods were used to assess the spatial and temporal changes of the NDVI in response to variations in natural conditions and human activities in Mongolia from 1982 to 2015. The corresponding individual and interactive driving forces, and the optimal range for the maximum NDVI value of vegetation distribution were also quantified. The area in which vegetation was degraded was roughly equal to the area of increase, but different vegetation types behaved differently. The desert steppe and the Gobi Desert both in arid regions have degraded significantly, whereas the meadow steppe and alpine steppe showed a significant upward trend. Precipitation can satisfactorily account for vegetation distribution. Changes of livestock quantity was the dominant factor influencing the changes of most vegetation types. The interactions of topographic factors and climate factors have significant effects on vegetation growth. In the region of annual precipitation between 331 mm and 596 mm, forest vegetation type and pine sandy soil type were found to be most suitable for the growth of vegetation in Mongolia. The findings of this study can help us to understand the appropriate range or type of environmental factors affecting vegetation growth in Mongolia, based on which we can apply appropriate interventions to effectively mitigate the impact of environmental changes on vegetation.With the continuous development of earth observation system technology and the continuous enrichment of statistical models, the research content and methods of the relationships between vegetation, climate change, and human activities have become increasingly diverse. The normalized density vegetation index (NDVI), derived from infrared channel and near-infrared channel remote sensing data, is a good indicator of vegetation growth status and spatial distribution density of vegetation, and is linearly related to vegetation distribution density [6,7]. A large number of ecological studies have been carried out related to vegetation change and its influencing factors using NDVI and statistical models. Temperature and precipitation, as important factors in the natural environment, are often used as research priorities to assess their impact on vegetation. However, the dominant factors contributing to NDVI in different regions vary considerably. The variety in vegetation and its connection to climate change have been investigated by Du et al. [5] and Zheng et al. [8] in China. These studies identified precipitation as the key climatic factor governing variation in NDVI. However, Guo et al. [9] found that temperature was the dominant factor on vegetation (NDVI) growth ...

Both steatosis and inflammation are key pathological events in the progression of non-alcoholic fatty liver disease (NAFLD). Probiotics are beneficial in the prevention and treatment of NAFLD. Bifidobacterium animalis subsp.lactis V9 (V9) is a newly isolated strain with favorable probiotic properties. The study aims to evaluate the effects and mechanisms of V9 on the hepatic steatosis and inflammatory responses in a rat model of NAFLD induced by high-fat diets (HFD). Our results showed that administration with V9 significantly attenuated HFD-induced increases in the levels of alanine transaminase (ALT) and aspartate aminotransferase (AST), accompanied by alleviated hepatic steatosis. V9 supplementation decreased the accumulation of hepatic triglyceride (TG) and free fatty acid (FFA), while increasing the levels of glycogen. The levels of serum glucose were also decreased in HFD rats administrated with V9. Meanwhile, the transcription of SREBP-1c and FAS was reduced and the hepatic expression of phosphorylated-AMPK and PPAR-α was restored by V9 administration. V9 suppressed the production of inflammatory cytokines (e.g. IL-6, IL-1β, and TNF-α) in HFD-fed rats. The anti-inflammatory effect of V9 was found to be associated with the inhibition of hepatic expression of TLR4, TLR9, NLRP3, and ASC mRNA. Furthermore, the activation of ERK, JNK, AKT and NF-κB was suppressed by V9 treatment. These results indicated that Bifidobacterium Lactis V9 improved NAFLD by regulating de novo lipid synthesis and suppressing inflammation through AMPK and TLR-NF-κB pathways, respectively. Key Points V9 supplementation alleviates HFD-induced metabolic disorder. V9 inhibited HFD-induced expression of FAS, SREBP1c and activated AMPK. V9 suppressed the TLR-NF-κB signaling pathway in HFD-fed rats.

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In this study, we investigated the potential of Lactobacillus plantarum isolated from Chinese traditional fermented foods to reduce the toxicity of aflatoxin B1 (AFB1), and its subsequent detoxification mechanism. Among all the investigated L. plantarum strains, L. plantarum C88 showed the strongest AFB1 binding capacity in vitro, and was orally administered to mice with liver oxidative damage induced by AFB1. In the therapy groups, the mice that received L. plantarum C88, especially heat-killed L. plantarum C88, after a single dose of AFB1 exposure, showed an increase in unabsorbed AFB1 in the feces. Moreover, the effects of L. plantarum C88 on the enzymes and non-enzymes antioxidant abilities in serum and liver, histological alterations of liver were assayed. The results indicated that compared to the control group, L. plantarum C88 alone administration induced significant increase of antioxidant capacity, but did not induce any significant changes in the histological picture. Compared to the mice that received AFB1 only, L. plantarum C88 treatment could weaken oxidative stress by enhancing the activity of antioxidant enzymes and elevating the expression of Glutathione S-transferase (GST) A3 through Nuclear factor erythroid (derived factor 2) related factor 2 (Nrf2) pathway. Furthermore, cytochrome P450 (CYP 450) 1A2 and CYP 3A4 expression was inhibited by L. plantarum C88, and urinary aflatoxin B1-N7-guanine (AFB-N7-guanine), a AFB1 metabolite formed by CYP 1A2 and CYP 3A4, was significantly reduced by the presence of viable L. plantarum C88. Meanwhile, the significant improvements were showed in histological pictures of the liver tissues in mice orally administered with viable L. plantarum C88. Collectively, L. plantarum C88 may alleviate AFB1 toxicity by increasing fecal AFB1 excretion, reversing deficits in antioxidant defense systems and regulating the metabolism of AFB1.