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Viruses 14(2), 381 (2022). doi:10.3390/v14020381 special issue: "Veterinary Infectious Diseases / Topic Editors: Dr. Chao-Nan Lin, Dr. Peck Toung Ooi", Published by MDPI, Basel

Using an extensive sample consisting of 30 emerging countries and 38 years of data, we examine the profitability of two momentum and two trend following strategies. Over the entire sample, we find excess returns that are economically and statistically significant for all four strategies. Furthermore, we show that the significance of the excess returns remains after adjusting for macroeconomic risk factors. In addition, we find that in spite of their relative neglect, trend strategies frequently demonstrate superior performance, compared to momentum strategies. However, contrary to previous research, we do not find that time series momentum strategies outperform cross-sectional momentum strategies. Finally, we show that the effectiveness of the alternative strategies is largely diminished once transactions costs and liberalizations in emerging markets are considered.

Chronic inflammation is strongly associated with approximately one-fifth of all human cancers. Arising from combinations of factors such as environmental exposures, diet, inherited gene polymorphisms, infections, or from dysfunctions of the immune response, chronic inflammation begins as an attempt of the body to remove injurious stimuli; however, over time, this results in continuous tissue destruction and promotion and maintenance of carcinogenesis. Here, we focus on intestinal inflammation and its associated cancers, a group of diseases on the rise and affecting millions of people worldwide. Intestinal inflammation can be widely grouped into inflammatory bowel diseases (ulcerative colitis and Crohn’s disease) and celiac disease. Long-standing intestinal inflammation is associated with colorectal cancer and small-bowel adenocarcinoma, as well as extraintestinal manifestations, including lymphomas and autoimmune diseases. This article highlights potential mechanisms of pathogenesis in inflammatory bowel diseases and celiac disease, as well as those involved in the progression to associated cancers, most of which have been identified from studies utilizing mouse models of intestinal inflammation. Mouse models of intestinal inflammation can be widely grouped into chemically induced models; genetic models, which make up the bulk of the studied models; adoptive transfer models; and spontaneous models. Studies in these models have lead to the understanding that persistent antigen exposure in the intestinal lumen, in combination with loss of epithelial barrier function, and dysfunction and dysregulation of the innate and adaptive immune responses lead to chronic intestinal inflammation. Transcriptional changes in this environment leading to cell survival, hyperplasia, promotion of angiogenesis, persistent DNA damage, or insufficient repair of DNA damage due to an excess of proinflammatory mediators are then thought to lead to sustained malignant transformation. With regard to extraintestinal manifestations such as lymphoma, however, more suitable models are required to further investigate the complex and heterogeneous mechanisms that may be at play.

Due to a higher probability for violation of hygiene measures, reconstruction work is a substantial food safety challenge for food business operators (FBOs). Here, we monitored a Listeria monocytogenes contamination scenario during a timely enduring reconstruction period that aimed at an expansion of the main building of a leading meat processing facility. Reconstruction took place while food production was ongoing. We used a longitudinal sampling scheme targeting 40 floor water drains distributed over the food processing environment (FPE) over a five year period. The population structure of L. monocytogenes was determined by PCR-serogrouping, pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). While the first sampling deciphered a baseline of contamination (45%), intensified sanitation measures decreased L. monocytogenes prevalence before commencement of work (5%). The reconstruction activities increased the prevalence of L. monocytogenes in the FPE (20.5%) and changed the population structure to a higher proportion of disease-associated genotypes (61%). During the first sampling ST121 was prevalent throughout the FPE, even in the packaging area. After the second and third sampling, following increased application of hypochlorite during sanitation, ST121 was only present in the raw material preparation area. A resilient flora was detected during three sampling events (ST8, ST9 and ST37) which might have not been exposed to daily cleaning in the floor drains. After the accomplishment of reconstruction work, the L. monocytogenes population structure shifted to the condition initially found (45% and 20.5% during the first and sixth sampling event). This paper indicates that reconstruction phases are high risk episodes for food safety in FPEs. Special precautions must be taken to avoid cross-contamination of products since reconstruction is usually ongoing for extended periods of time.

Chronic inflammation is strongly associated with approximately one-fifth of all human cancers. Arising from combinations of factors such as environmental exposures, diet, inherited gene polymorphisms, infections, or from dysfunctions of the immune response, chronic inflammation begins as an attempt of the body to remove injurious stimuli; however, over time, this results in continuous tissue destruction and promotion and maintenance of carcinogenesis. Here, we focus on intestinal inflammation and its associated cancers, a group of diseases on the rise and affecting millions of people worldwide. Intestinal inflammation can be widely grouped into inflammatory bowel diseases (ulcerative colitis and Crohn’s disease) and celiac disease. Long-standing intestinal inflammation is associated with colorectal cancer and small-bowel adenocarcinoma, as well as extraintestinal manifestations, including lymphomas and autoimmune diseases. This article highlights potential mechanisms of pathogenesis in inflammatory bowel diseases and celiac disease, as well as those involved in the progression to associated cancers, most of which have been identified from studies utilizing mouse models of intestinal inflammation. Mouse models of intestinal inflammation can be widely grouped into chemically induced models; genetic models, which make up the bulk of the studied models; adoptive transfer models; and spontaneous models. Studies in these models have lead to the understanding that persistent antigen exposure in the intestinal lumen, in combination with loss of epithelial barrier function, and dysfunction and dysregulation of the innate and adaptive immune responses lead to chronic intestinal inflammation. Transcriptional changes in this environment leading to cell survival, hyperplasia, promotion of angiogenesis, persistent DNA damage, or insufficient repair of DNA damage due to an excess of proinflammatory mediators are then thought to lead to sustained malignant transformation. With regard to extraintestinal manifestations such as lymphoma, however, more suitable models are required to further investigate the complex and heterogeneous mechanisms that may be at play.

Unregulated international flow of foods poses a danger to human health, as it may be contaminated with pathogens. Recent studies have investigated neglected routes of pathogen transmission and reported the occurrence of Listeria monocytogenes in food illegally imported into the European Union (EU), either confiscated at four international airports or sold illegally on the Romanian black market. In this study we investigated the genotype diversity and the amino acid sequence variability of three main virulence factors of 57 L. monocytogenes isolates. These isolates were derived from 1474 food samples illegally imported into the EU and originated from 17 different countries. Multilocus sequence typing revealed 16 different sequence types (STs) indicating moderate genotype diversity. The most prevalent STs were ST2, ST9, and ST121. The pulsed-field gel electrophoresis (PFGE) analysis resulted in 34 unique pulsotypes. PFGE types assigned to the most prevalent STs (ST2, ST9, and ST121) were highly related in their genetic fingerprint. Internalin A (InlA) was present in 20 variants, including six truncated InlA variants, all harbored by isolates of ST9 and ST121. We detected eight ST-specific listeriolysin O (LLO) variants, and among them, one truncated form. The actin-assembly-inducing protein ActA was present in 15 different ST-specific variants, including four ActA variants with an internal truncation. In conclusion, this study shows that L. monocytogenes, isolated from illegally imported food, have moderate genotype diversity, but diverse virulence factors variants, mainly of InlA.

Resveratrol is a naturally occurring polyphenolic compound with various pharmacological activities. It is unknown whether the expression of metabolizing enzymes correlates with resveratrol levels in organs and tissues. Therefore, we investigated the metabolism and tissue distribution of resveratrol in mice and assessed its association with the expression of UDP-glucuronosyltransferase (Ugt) and sulfotransferase (Sult) genes. Plasma, urine, feces, and various organs were analyzed using high-performance liquid chromatography at up to 8 h after intragastric resveratrol administration. The metabolism of resveratrol was pronounced, leading to the formation of resveratrol glucuronides and sulfates. Concentrations of resveratrol and its metabolites were high in the gastrointestinal organs, urine, and feces, but low in the liver and kidneys. In lung, heart, thymus, and brain tissues, parent resveratrol levels exceeded the sulfate and glucuronide concentrations. The formation of resveratrol conjugates correlated with the expression of certain Ugt and Sult genes. Reverse transcription quantitative PCR (RT-qPCR) analysis revealed high mRNA expression of Ugt1a1 and Ugt1a6a in the liver, duodenum, jejunum, ileum, and colon, leading to high concentrations of resveratrol-3-O-glucuronide in these organs. Strong correlations of resveratrol-3-O-sulfate and resveratrol-3-O-4'-O-disulfate formation with Sult1a1 mRNA expression were also observed, particularly in the liver and colon. In summary, our data revealed organ-specific expression of Sults and Ugts in mice that strongly affects resveratrol concentrations; this may also be predictive in humans following oral uptake of dietary resveratrol.

Virtually all evidence on the efficacy of momentum strategies arises from the post-1962 era, and momentum returns across different markets and asset classes are highly positively correlated. We examine industry momentum in an earlier time, and find these strategies would have earned returns over the 1871-1925 and 1871-1938 periods that are moderately similar to those in the modern era. We also show that the market state dependence of industry momentum strategies is similar between the two eras. Overall, our findings confirm that both the profitability and statedependence of momentum strategies are pervasive and unlikely to be due solely to data-mining.

We show that previous findings regarding the profitability of trend-following trading rules over intermediate horizons in futures markets also extend to individual U.S. stocks. Portfolios formed using technical indicators such as moving average or channel ratios, without employing cross-sectional rankings of any kind, tend to perform about as well as the more commonly examined momentum strategies. The profitability of these strategies appears significant, both statistically and economically, through 2007, but evidence of profitability vanishes after 2007. Market-state dependence, while clearly present, does not explain the post-2007 reduction in returns to these strategies.

The suitability for consumers of a variety of raw milk cheeses purchased over the Internet was investigated in terms of packaging, labelling, physicochemical parameters and microbiological safety. 108 purchases from seven European countries were examined. The prevalences of Salmonella spp., Listeria monocytogenes, Escherichia coli and coagulase positive staphylococci (SA) were determined. All 108 samples were described on websites as raw milk cheeses and thereby qualified for this study. However, after delivery it was noted that 4.6% (5/108) of cheeses were labelled to be manufactured from heat-treated or pasteurized milk. Delivery duration ranged from 24 h to six days. Immediately upon receipt cheese temperatures were observed to range between 5 and 23 °C, whereas in 61.5% of all cases the temperature was higher than 15 °C. Cheese labelling was examined in respect of EC Guideline 2000/13 and Regulation No. 853/2004. Only 17.6% (19/108) of cheeses were properly labelled and fulfilled all European guideline requirements. In 50.9%, 38.8%, 46.3% and 39.8% of all cases (i) specific storage requirements, (ii) name and address of the manufacturer/packer or seller, (iii) net weight and (iv) shelf life (use by date), were missing. Even the labelling information “made from raw milk” was not apparent on 36% of all cheese items delivered. The major foodborne pathogen L. monocytogenes was detected in 1.9% of all samples, one of which had counts of 9.5 × 103 CFU/g. None of the 108 investigated cheeses showed a pH ≤ 5.0 and aw value ≤0.94 which are the limiting values for growth of L. monocytogenes. For two samples (0.9%) and 11 samples (10.2%) the pH and the aw value was ≤4.4 or ≤0.92, respectively at least at one of three stipulated time points (receipt, mid-shelf-life and at expiry). Salmonella spp. could not be detected in any of the samples. E. coli and SA could be detected in a total of 29.6% (≥10 CFU/g; 32/108) and 8.3% (≥100 CFU/g; 9/108) of samples, respectively, indicating poor conditions of hygiene. Results reveal that labelling and hygiene concerns about the safety of Internet purchased cheeses in Europe are justified.

We examine the determinants of market value and underpricing for 1221 IPOs using a stochastic frontier model applied to the previously unexamined 1999-2010 period. We find that the book value of assets, the percentage of shares retained by the original owners of the firm, the commission rate and the reputational rankings of the underwriters are the most important determinants of firm value and underpricing. We estimate that the mean ex-ante underpricing is 39.7% which, while seemingly high, is consistent with unusually large first day returns in our sample period and our focus on emerging growth IPOs. However, we do not find a positive relation between our modelbased measure of ex-ante underpricing and first day aftermarket returns at the firm level.

It has been possible to determine the genotype diversity of Listeria monocytogenes in the actual cheese lots of acid curd cheese that caused a multinational outbreak between 2009 and 2010. Following product recall in January 2010 all lots were investigated. A total of 422 L. monocytogenes isolates were characterized by genotyping. In a first approach the PCR serogroups were defined by multiplex-PCR assays. Subsequently, the isolates were subtyped by pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). Sequence types were assigned by submitting the DNA sequences to the Listeria MLST database at the Institute Pasteur. The serogroup PCR resulted in a homogeneous 1/2a - 3a (genetic linage II) cluster. The generated PFGE patterns divided the strains into two clusters (type 1 and 2) diverging at a homogeneity level of 74%. PFGE-type 2 was predominant, accounting for 98.3% (n = 415/422) of the isolates and was isolated during the whole period of acid curd cheese processing (01.12.2009-13.01.2010). 1.7% of all tested L. monocytogenes isolates (n = 7/422) belonged to PFGE-type 1 and were isolated from 28% of all cheese lots (n = 5/18) produced between the time span of 08.12.2009 to 13.01.2010. Furthermore, PFGE-type 1 and 2 showed the same PFGE patterns as the human outbreak strains (clone 1 and clone 2).

Chronic inflammation is strongly associated with approximately one-fifth of all human cancers. Arising from combinations of factors such as environmental exposures, diet, inherited gene polymorphisms, infections, or from dysfunctions of the immune response, chronic inflammation begins as an attempt of the body to remove injurious stimuli; however, over time, this results in continuous tissue destruction and promotion and maintenance of carcinogenesis. Here, we focus on intestinal inflammation and its associated cancers, a group of diseases on the rise and affecting millions of people worldwide. Intestinal inflammation can be widely grouped into inflammatory bowel diseases (ulcerative colitis and Crohn's disease) and celiac disease. Long-standing intestinal inflammation is associated with colorectal cancer and small-bowel adenocarcinoma, as well as extraintestinal manifestations, including lymphomas and autoimmune diseases. This article highlights potential mechanisms of pathogenesis in inflammatory bowel diseases and celiac disease, as well as those involved in the progression to associated cancers, most of which have been identified from studies utilizing mouse models of intestinal inflammation. Mouse models of intestinal inflammation can be widely grouped into chemically induced models; genetic models, which make up the bulk of the studied models; adoptive transfer models; and spontaneous models. Studies in these models have lead to the understanding that persistent antigen exposure in the intestinal lumen, in combination with loss of epithelial barrier function, and dysfunction and dysregulation of the innate and adaptive immune responses lead to chronic intestinal inflammation. Transcriptional changes in this environment leading to cell survival, hyperplasia, promotion of angiogenesis, persistent DNA damage, or insufficient repair of DNA damage due to an excess of proinflammatory mediators are then thought to lead to sustained malignant transformation. With regard to extraintestinal manifestations such as lymphoma, however, more suitable models are required to further investigate the complex and heterogeneous mechanisms that may be at play.

Stem cell research has been focused on niche signaling and epigenetic programming of stem cells. However, epigenetic programming of niche cells remains unexplored. We showed previously that Piwi plays a crucial role in Piwi-interacting RNA-mediated epigenetic regulation and functions in the niche cells to maintain germline stem cells (GSCs) in the Drosophila ovary. To investigate the epigenetic programming of niche cells by Piwi, we screened mutations in the Polycomb and trithorax group genes, and an enhancer of Polycomb and trithorax called corto, for their potential genetic interaction with piwi. corto encodes a chromatin protein. corto mutations restored GSC division in mutants of piwi and fs(1)Yb (Yb), a gene that regulates piwi expression in niche cells to maintain GSCs. Consistent with this, corto appears to be expressed in the niche cells and is not required in the germline. Furthermore, in corto-suppressed Yb mutants, the expression of hedgehog (hh) is restored in niche cells, which is likely responsible for corto suppression of the GSC and somatic stem cell defects of Yb mutants. These results reveal a novel epigenetic mechanism involving Corto and Piwi that defines the fate and signaling function of niche cells in maintaining GSCs.

This paper examines the performance of trend-following trading strategies in commodity futures markets using a monthly dataset spanning 48 years and 28 markets. We find that all parameterizations of the dual moving average crossover and channel strategies that we implement yield positive mean excess returns net of transactions costs in at least 22 of the 28 markets. When we pool our results across markets, we show that all of the trading rules earn hugely significant positive returns that prevail over most subperiods of the data as well. These results are robust with respect to the set of commodities the trading rules are implemented with, distributional assumptions, data-mining adjustments and transactions costs, and help resolve divergent evidence in the extant literature regarding the performance of momentum and pure trend-following strategies that is otherwise difficult to explain.

Yb regulates the proliferation of both germline and somatic stem cells in the Drosophila melanogaster ovary by activating piwi and hh expression in niche cells. In this study, we show that Yb protein is localized as discrete cytoplasmic spots exclusively in the somatic cells of the ovary and testis. These spots, which are different from all known cytoplasmic structures in D. melanogaster, are evenly electron-dense spheres 1.5 µm in diameter (herein termed the Yb body). The Yb body is frequently associated with mitochondria and a less electron-dense sphere of similar size that appears to be RNA rich. There are one to two Yb bodies/cell, often located close to germline cells. The N-terminal region of Yb is required for hh expression in niche cells, whereas the C-terminal region is required for localization to Yb bodies. The entire Yb protein is necessary for piwi expression in niche cells. A double mutant of Yb and a novel locus show male germline loss, revealing a function for Yb in male germline stem cell maintenance.

In this study, we examine financial reporting lags, the incidence of late filing, and the relationship between reporting lags, firm performance and the degree of capital market scrutiny. We use a large sample of firms spanning 22 countries over a eleven-year period. A focal point of our analysis is whether the incidence of late filing, and the relations between reporting days and other variables, differ systematically between common and code law countries. Relative to U.S. firms, we report that the time taken and allowed for filing is usually longer in other countries and that the statutory requirement is more frequently violated. Timely filing is found to be less frequent in code law countries. Poor firm performance and longer reporting lags are more strongly linked in common law countries. We also find that whereas greater capital market scrutiny and more timely filing are related, there is less support for a relationship between the level of debt financing and timely filing in code law countries.

This article describes the principles and limitations of methods used to investigate reactive oxygen species (ROS) protective properties of dietary constituents and is aimed at providing a better understanding of the requirements for science based health claims of antioxidant (AO) effects of foods. A number of currently used biochemical measurements aimed of determining the total antioxidant capacity and oxidised lipids and proteins are carried out under unphysiologcial conditions and are prone to artefact formation. Probably the most reliable approaches are measurements of isoprostanes as a parameter of lipid peroxidation and determination of oxidative DNA damage. Also the design of the experimental models has a strong impact on the reliability of AO studies: the common strategy is the identification of AO byin vitroscreening with cell lines. This approach is based on the assumption that protection towards ROS is due to scavenging, but recent findings indicate that activation of transcription factors which regulate genes involved in antioxidant defence plays a key role in the mode of action of AO. These processes are not adequately represented in cell lines. Another shortcoming ofin vitroexperiments is that AO are metabolisedin vivoand that most cell lines are lacking enzymes which catalyse these reactions. Compounds with large molecular configurations (chlorophylls, anthocyans and polyphenolics) are potent AOin vitro, but weak or no effects were observed in animal/human studies with realistic doses as they are poorly absorbed. The development of -omics approaches will improve the scientific basis for health claims. The evaluation of results from microarray and proteomics studies shows that it is not possible to establish a general signature of alterations of transcription and protein patterns by AO. However, it was shown that alterations of gene expression and protein levels caused by experimentally induced oxidative stress and ROS related diseases can be normalised by dietary AO.

Unlike previous papers, which have focused on the timeliness ranks, we examine Value Line’s 3–5 year projections for stock returns, earnings, sales and related measures. We find that Value Line’s stock return and earnings forecasts exhibit large positive bias, although their sales predictions do not. For stock returns, Value Line’s projections lack predictive power; for other variables predictive power may exist to some degree. Our findings suggest the spectacular past performance of the timeliness indicator reflects either close alignment with other known anomalies or data mining, and that investors and researchers should use Value Line’s long-term projections with caution.

Commodity futures and equity markets differ in several important respects. Nevertheless, it was found that momentum profits in commodities are highly significant for holding periods as long as 9 months, and returns to momentum strategies are roughly equal in magnitude to those that have been reported in stocks. The profits documented are too large to be subsumed by transactions costs. Although the momentum strategies appear to be quite risky, their profitability cannot be fully accounted for in the context of a market factor model. Further, it is shown that momentum profits eventually reverse if positions are maintained long enough after portfolio formation. © 2007 Wiley Periodicals, Inc. Jrl Fut Mark 27:227–256, 2007