Estimating annual soil carbon loss in agricultural peatland soils using a nitrogen budget approach.

Around the world, peatland degradation and soil subsidence is occurring where these soils have been converted to agriculture. Since initial drainage in the mid-1800s, continuous farming of such soils in the California Sacramento-San Joaquin Delta (the Delta) has led to subsidence of up to 8 meters in places, primarily due to soil organic matter (SOM) oxidation and physical compaction. Rice (Oryza sativa) production has been proposed as an alternative cropping system to limit SOM oxidation. Preliminary research on these soils revealed high N uptake by rice in N fertilizer omission plots, which we hypothesized was the result of SOM oxidation releasing N. Testing this hypothesis, we developed a novel N budgeting approach to assess annual soil C and N loss based on plant N uptake and fallow season N mineralization. Through field experiments examining N dynamics during growing season and winter fallow periods, a complete annual N budget was developed. Soil C loss was calculated from SOM-N mineralization using the soil C:N ratio. Surface water and crop residue were negligible in the total N uptake budget (3 - 4 % combined). Shallow groundwater contributed 24 - 33 %, likely representing subsurface SOM-N mineralization. Assuming 6 and 25 kg N ha-1 from atmospheric deposition and biological N2 fixation, respectively, our results suggest 77 - 81 % of plant N uptake (129 - 149 kg N ha-1) was supplied by SOM mineralization. Considering a range of N uptake efficiency from 50 - 70 %, estimated net C loss ranged from 1149 - 2473 kg C ha-1. These findings suggest that rice systems, as currently managed, reduce the rate of C loss from organic delta soils relative to other agricultural practices

Effect of wheat distillers dried grains with solubles or sugar beet pulp on prevalence of Salmonella enterica Typhimurium in weaned pigs

Salmonella enterica Typhimurium (ST) is of concern in the swine industry with relevance for animal health and consumer safety. Nutritional strategies might help to reduce ST infection and transmission. This study examined the potential of wheat (Triticum aestivum) distillers dried grains with solubles (DDGS) and sugar beet (Beta vulgaris) pulp (SBP) to alter intestinal microbial communities and ST shedding using a Trojan model. Weaned pigs (n = 105; 28.5 ± 3.5 d of age) were separated into 3 treatment groups (7 pigs/pen) and fed a wheat-based control diet or the control diet formulated with 15% wheat DDGS or 6% SBP inclusion. Following 12 d of diet adaptation, 2 pigs/pen were inoculated with 2 x 109 cfu ST, resistant to novobiocin and nalidixic acid. Fecal swabs were taken from infected pigs and pen-mates (contact pigs) for 9 d following challenge, enriched in nutrient broth for 24 h, and plated on selective media to determine prevalence of ST. The ranges of prevalence of ST in feces were from 90 to 100% in challenged pigs and 74 to 78% in contact pigs. No influence of treatment on rectal temperature and prevalence of ST in contact pigs were observed. Fifteen contact pigs were euthanized per treatment group on 9 and 10 d postchallenge to enumerate in intestinal contents (ileum, cecum, and proximal colon), Lactobacillus spp., Enterobacteriaceae, and Clostridium clusters I, VI, and XVIa by quantitative PCR (qPCR) and to determine ST prevalence by selective culture. No significant effects of diet were observed with respect to ST prevalence in feces, ileum, cecum, colon, and lymph nodes of contact pigs. Compared with the control diet, DGGS and SBP diets showed a trend towards increased (P < 0.1) number of Lactobacillus species in the cecum and colon. Although both wheat DGGS and SBP tended to increase the Lactobacillus spp. neither of the feed ingredients affected ST prevalence

Global H-NS counter-silencing by LuxR activates quorum sensing gene expression

Bacteria coordinate cellular behaviors using a cell-cell communication system termed quorum sensing. In Vibrio harveyi, the master quorum sensing transcription factor LuxR directly regulates \u3e100 genes in response to changes in population density. Here, we show that LuxR derepresses quorum sensing loci by competing with H-NS, a global transcriptional repressor that oligomerizes on DNA to form filaments and bridges. We first identified H-NS as a repressor of bioluminescence gene expression, for which LuxR is a required activator. In an hns deletion strain, LuxR is no longer necessary for transcription activation of the bioluminescence genes, suggesting that the primary role of LuxR is to displace H-NS to derepress gene expression. Using RNA-seq and ChIP-seq, we determined that H-NS and LuxR co-regulate and co-occupy 28 promoters driving expression of 63 genes across the genome. ChIP-PCR assays show that as autoinducer concentration increases, LuxR protein accumulates at co-occupied promoters while H-NS protein disperses. LuxR is sufficient to evict H-NS from promoter DNA in vitro, which is dependent on LuxR DNA binding activity. From these findings, we propose a model in which LuxR serves as a counter-silencer at H-NS-repressed quorum sensing loci by disrupting H-NS nucleoprotein complexes that block transcription

Profiling the vendors of COVID‐19 related product on the Darknet: An observational study

Background In a time of unprecedented global change, the COVID-19 pandemic has led to a surge in demand of COVID-19 vaccines and related certifications. Mainly due to supply shortages, counterfeit vaccines, fake documentation, and alleged cures to illegal portfolios, have been offered on darkweb marketplaces (DWMs) with important public health consequences. We aimed to profile key DWMs and vendors by presenting some in-depth case studies. Methods A non-systematic search for COVID-19 products was performed across 118 DWMs. Levels of activity, credibility, content, COVID-19 product listings, privacy protocols were among the features retrieved. Open web fora and other open web sources were also considered for further analysis of both functional and non functional DWMs. Collected data refers to the period between January 2020 and October 2021. Results A total of 42 relevant listings sold by 24 vendors across eight DWMs were identified. Four of these markets were active and well-established at the time of the study with good levels of credibility. COVID-19 products were listed alongside other marketplace content. Vendors had a trusted profile, communicated in English language and accepted payments in cryptocurrencies (Monero or Bitcoin). Their geographical location included the USA, Asia and Europe. While COVID-19 related goods were mostly available for regional supply, other listings were also shipped worldwide. Interpretation Findings emerging from this study rise important questions about the health safety of certain DWMs activities and encourage the development of targeted interventions to overcome such new and rapidly expanding public health threats. Funding CovSaf, National Research centre on Privacy, Harm Reduction and Adversarial Influence Online (REPHRAIN), Commonwealth Fund

Path Integrals in Polar Field Variables in QFT

We show how to transform a $d$-dimensional Euclidean path integral in terms of two (Cartesian) fields to a path integral in terms of polar field variables. First we present a conjecture that states how this transformation should be done. Then we show that this conjecture is correct in the case of two toy models. Finally the conjecture will be proven for a general QFT model with two fields

Lifetime prevalence of novel psychoactive substances use among adults in the USA: Sociodemographic, mental health and illicit drug use correlates. Evidence from a population-based survey 2007–2014

INTRODUCTION: As Novel psychoactive substances (NPS) are conceived to mimic the effects of common illicit drugs, they represent a serious public health challenge due to the spike in intoxications and fatalities that have been linked to their use. This study aims to provide epidemiological data on NPS use in the USA, determining lifetime prevalence of use and defining demographic, socioeconomic, drug use patterns and mental health correlates. METHODS: This study uses secondary data from the US National Survey on Drug Use and Health (NSDUH), which is a large cross-sectional population-based survey carried out annually in the USA. We analysed data from 2007-14 (N = 307,935) using bivariate descriptive analysis and binary logistic regression to calculate prevalence and determine factors underlying NPS consumption. Adjusted odds ratios (OR) with 95% CI's were calculated for a set of selected independent variables. RESULTS AND DISCUSSION: Our analysis NSDUH from 2007-14 highlights an increase in NPS use among adults, especially among white young men aged 18 to 25. Although the level of education of NPS users was relatively higher as compared to non-users, NPS users seemed to have a less wealthy situation. However, socioeconomic vulnerability appeared to be less important than mental health issues as a correlate to NPS use. NPS users seem to have followed a pattern of polysubstance use throughout their life, which involves both traditional illicit drugs and classic synthetic drugs. As NPS use seemed to be more prevalent among people having mental health issues, the rise in their use may have a negative impact on population mental health outcomes. CONCLUSION: Further comparative research on trends in NPS use and potential public health responses would be instrumental for developing appropriate health interventions, including drug checking, education for users and training for healthcare professionals working both within emergency wards and in/outpatient addiction and mental health services

Gut bacterial deamination of residual levodopa medication for Parkinson's disease

BACKGROUND: Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by both motor and non-motor symptoms. Gastrointestinal tract dysfunction is one of the non-motor features, where constipation is reported as the most common gastrointestinal symptom. Aromatic bacterial metabolites are attracting considerable attention due to their impact on gut homeostasis and host's physiology. In particular, Clostridium sporogenes is a key contributor to the production of these bioactive metabolites in the human gut. RESULTS: Here, we show that C. sporogenes deaminates levodopa, the main treatment in Parkinson's disease, and identify the aromatic aminotransferase responsible for the initiation of the deamination pathway. The deaminated metabolite from levodopa, 3-(3,4-dihydroxyphenyl)propionic acid, elicits an inhibitory effect on ileal motility in an ex vivo model. We detected 3-(3,4-dihydroxyphenyl)propionic acid in fecal samples of Parkinson's disease patients on levodopa medication and found that this metabolite is actively produced by the gut microbiota in those stool samples. CONCLUSIONS: Levodopa is deaminated by the gut bacterium C. sporogenes producing a metabolite that inhibits ileal motility ex vivo. Overall, this study underpins the importance of the metabolic pathways of the gut microbiome involved in drug metabolism not only to preserve drug effectiveness, but also to avoid potential side effects of bacterial breakdown products of the unabsorbed residue of medication

Comparative genomic hybridization of germ cell tumors of the adult testis: Confirmation of karyotypic findings and identification of a 12p- amplicon

Comparative genomic hybridization (CGH) was carried out on 15 primary testicular germ cell tumors (TGCT) of adolescents and adults and two metastatic residual tumors after chemotherapeutic treatment. The results were compared with karyotypic data obtained form the same tumor specimens after direct harvesting of metaphases or short-term in vitro culture. Both techniques revealed that the most consistent abnormality in primary TGCT is gain of 12p-sequences. Although in most cases over-representation of the complete short arm was observed, CGH revealed a specific amplification of 12p11.1-p12.1 region in two independent primary tumors. In addition, loss of (parts of) chromosome 13 (always involving q31-qter), and gain of (parts of) chromosome 7 (mostly involving q11), (parts of) chromosome 8, and the X chromosome were detected in more than 25% of the tumors by this latter technique. Loss of 6q15-q21 in both re