Fitness and pathogenicity of outbreak causing salmonella upon short-term exposure to groundwater with residual antibiotics

The changes in survival and pathogenicity of three Salmonella enterica subsp. enterica serotypes upon short term exposure to groundwater with residual antibiotics have been studied in relationship to overall microbial fitness. A wild type flagellated Salmonella enterica ser. Typhimurium outbreak strain, a mutant Salmonella enterica ser. Typhimurium strain, and a wild type avian disease-causing Salmonella enterica ser. Pullorum strain were exposed to a range of ionic strength (3-30 mM) groundwater with residual antibiotics for 6-24 hours. Exposed organisms’ pathogenicity was tested in vitro exposure to a human epithelial cell line (HEp2). Resistance profiles against 10 common antibiotics were also tested and compared to unexposed controls. Results show minor antibiotic resistance changes for S. enterica ser. Typhimurium strains in response to some antibiotic classes mediated with active efflux pumps. This trend was not observed for S. enterica ser. Pullorum, suggesting that resistance found in groundwater exposed organisms might be strain-dependent. In vitro epithelial cell invasion assays showed bacterial invasion of HEp2 cells initially decreases with time and increases after 24 hours. It is concluded that S. enterica serotypes reaching groundwater environments in the presence of residual antibiotics may exhibit increased levels of pathogenicity, strain-dependent resistance to antibiotics, and sustained levels of viability.Bu çalışmada kalıntı miktarda antibiyotik içeren yeraltı sularına kısa süreli maruz bırakılan üç Salmonella enterica subsp. enterica serotipinin hastalık yapıcı özelliklerindeki değişiklikler ve hayatta kalabilme seviyeleri genel mikrobiyel fitnes çerçevesinde incelenmiştir. Serotipler gerçek bir salgından izole edilen kamçılı doğal fenotip Salmonella enterica ser. Typhimurium, kamçısı fonksiyonel olmayan bir başka Salmonella enterica ser. Typhimurium suşu ve kuş türlerinde salgına yol açan doğal fenotip Salmonella enterica ser. Pullorum’dan oluşup, iyon şiddeti değişken (3-30 mM) ve kalıntı miktarda antibiyotik içeren yeraltı suyuna 6-24 saat sürecince maruz bırakılmıştır. Serotiplerin hastalık yapıcı özellikleri in vitro koşullarda HEp2 türü insan epitel hücre kültürleri kullanılarak ölçülmüştür. Antibiyotik direnç seviyeleri ise yaygın kullanılan 10 antibitiyotiğe karşı disk difüzyon testi yardımıyla belirlenmiştir. Deneyler sonucunda S. enterica ser. Typhimurium suşlarında antibiyotik direnç seviyelerinde az miktarda artış gözlenirken S. enterica ser. Pullorum suşunda değişiklik gözlenmemiştir. In vitro deneylerde ise suşların HEp2 hücrelerini enfekte etmeleri zamanla önce azalmış, 24 saatlik dilim sonunda ise artmıştır. Sonuç olarak, kalıtsal antibiyotik içeren yeraltı sularına temas eden S. enterica serotiplerinin hastalık yapıcı karakterlerinin arttığı, antibiyotik direnç seviyelerinin suşa bağlı olarak değişkenlik gösterirken hayatta kalma oranlarının yüksek olduğu gözlenmiştir

Turkish corporate governance goes mainstream: a socio-legal analysis of Turkey's recent corporate governance law reforms

This thesis examines the reasons, methods, and implications of the legal reforms in Turkey’s corporate governance framework. The mainstream model of corporate governance that is based on the shareholder primacy theory, which currently enjoys global hegemony, holds that the purpose of the company is to maximize shareholder wealth. Its critics argue that corporate governance should also pursue stakeholder interests, including societal interests. The thesis moves beyond these debates by analysing the recent reforms in Turkey, an emerging market, from a socio-legal perspective to determine whether Turkish corporate governance laws have conformed to the mainstream model. This research’s unique contribution to the body of knowledge lies in its inter-disciplinary and critical approach in its examination of Turkish corporate governance laws. The thesis begins by exploring the process by which the shareholder primacy theory gained prominence alongside the rise of neoliberal ideology. It illustrates how this theory has been disseminated outside the Anglo-American context through the promotion of ‘universal’ corporate governance standards. It finds that Turkey has conformed to the mainstream model as evidenced by the alignment of its corporate governance laws with the OECD Principles. Nevertheless, while Turkish companies are characterised by concentrated ownership with family owners in control, the mainstream model is derived from an Anglo-American system of wide share dispersal that reduces corporate governance to an agency problem of aligning the interests of managers and shareholders. In this context, the research employs a Marxist theoretical framework to uncover the reason for imposing an Anglo-American variant of corporate governance rules on Turkish companies. Turkey has justified the recent corporate governance reforms with the need to attract foreign investors and its aspiration of joining the EU. The new legislation focuses on the rights of minority shareholders in an attempt to curb the power of controlling owners in favour of outside shareholders. Across this backdrop, the thesis critically assesses the implications of these legal reforms. It examines the possibility of the ownership structure of listed companies transforming from concentrated to diffused ownership, which is more suitable for the functioning of the mainstream model. Furthermore, the thesis discusses the consequences of the change of control from family owners to dispersed shareholders, concluding that this will align the objectives of Turkish companies with the interests of global investors. Overall, this thesis reveals the broader context in which neoliberal mainstream corporate governance laws are constructed, disseminated, and operate in capitalism, so that their raison d’etre can be understood and challenged

Financial parameters selection for a forecasting system on Istanbul Stock Exchange

Finansal piyasalara odaklanan ve farklı amaçlarla yürütülen bir çok araştırmada fiyat veya getiri tahminine yönelik yoğun bir ilgi görülmektedir. Bu ilginin temel nedeni finansal piyasaların dinamiğini tespit etmektir. Piyasa davranışının belirlenmesi; makro yatırım politikalarından bireysel tasarruflara kadar birikimlerin yönlendirilmesinde, portföy optimizasyonundan piyasa ekonomisinin işleyişine kadar bir çok konuda yol gösterici olacaktır. Başka bir deyişle hisse senedi fiyat hareketlerinin tahmin edilebilirliğinin araştırılması; akademisyenlerin etkin pazar kuramını sınamasına yardımcı olurken; rasyonel ilişkiler tespit edilirse, yatırım uzmanları güvenilir getiri sağlayan bir işlem sistemi oluşturulabileceklerdir. Bu çalışmanın amacı, İMKB-100 endeks hareketlerini tahmin etmede; gayrısafi milli hasıla, sanayi üretim endeksi gibi makro ekonomik değişkenlerin ve reel gösterge faiz oranı, döviz kurları gibi finansal verilerin kullanılabilirliğini araştırmaktır. Finansal piyasalarda fiyat tahminine yönelik bir çok modelleme çalışması yürütülmüş, ancak her dönem ve her piyasada kullanılabilir bir sistem oluşturulamamıştır. Zira hisse senedi fiyatları üzerinde, tümü tahmin modellemesinde kullanılamayacak kadar çok sayıda lokal ve global değişkenin (meteorolojik ve astrolojik değişkenlere kadar) etkisi söz konusudur. Ülkemizde de farklı istatistiksel çalışmalarda finansal göstergelerin, İMKB Hisse Senedi Piyasası’ndaki fiyat hareketleri ile ilişkisi araştırılmıştır. Ayrıca son yıllarda sözkonusu ilişkilerin analizi yerine, değişkenlerin doğrudan endeks tahmininde kullanılabilirliği incelenmektedir. Çalışmada girdiler, mevsimsel ve enflasyonist etkilerden arındırıldıktan sonra İMKB-100 Endeksi ile ilişkileri irdelenmiş ve son olarak İleri Beslemeli Geri Yayılımlı (İBGYYSA) bir ağ tipi için uygun normalizasyon yöntemi araştırılmıştır. Anahtar Kelimeler: Menkul değer piyasalarında tahminleme, yapay sinir ağları, finansal pazarlarda tahmin parametreleri.In the last decade, with the growth of computational facilities, there are many academic attempts about financial market prediction. Because of the huge sort of local and global data that may affect market trends, forecasting models developed until today have been only effective in few markets and for a limited period of time. Studies about Istanbul Stock Exchange (ISE) are limited. Determining the complex relationship between financial markets and economic parameters needs a chaotic approach. Chaos is a nonlinear deterministic process which only appears random because it cannot be easily expressed. Multivariate analytical techniques using both quantitative and qualitative variables have repeatedly been used to help form the basis of investor stock price expectations and hence, influence investment decision making. However, the performance of multivariate analytical techniques is often less than conclusive and needs to be improved to more accurately forecast stock price performance. A neural network (NN) method has demonstrated its capability of addressing complex problems. A neural network method may be able to enhance an investor's forecasting ability. There are several motivations for trying to predict stock market prices. But initial background needs of almost everyone is to investigate the market behavior, because each study about financial markets starts on that base. The most principal motivation is naturally financial gain. Finding any system that can consistently give greater revenue then the average return in the dynamic market place, is very important for the owner of the system, to give market players the impression of being trustworthy. Moreover, many investors are continually looking for this superior system which will yield them higher returns. Another motivation for researchers is the Efficient Market Hypothesis (EMH). It has been proposed in the EMH that markets are so efficient and profit opportunities are discovered so quickly that no one can catch superior performance. Hypothesis states that no system can continually beat the market because if this system becomes public, everyone will use it, thus negating its potential gain. There has been an ongoing debate on the validity of the EMH, some researchers use forecast results to validate their claims, other observers trying to demonstrate that the market is weak in efficiency. Validity of EMH is very important for the board managers point of view. If it can be proved that the market behavior is rational, while researchers evaluate the concept of a new efficient market, it would be possible to attract new resources to the market and create a new transaction system in which investors believe. No matter what the prediction purpose and methodology are the first step is to choose the parameters that really represent the market direction of movement and the level of variation. On the other hand, typical investors trading behaviors have been guided by two main perspectives; namely; Fundamental and technical analysis. While technical analysis uses only past market prices and volume, fundamental analysis is derived from external information which comes from the eco­nomic system encircling the market. This information consists of interest rates, prices and returns of other assets, and many other macro or micro economic variables. The aim of this study was to evaluate the effectiveness of using macroeconomic indicators such as; gross national product, industrial production level and financial data such as; real benchmark, currency exchange rates, in predicting movements in the ISE 100 Index (ISE-100). Availability of midterm economic and financial indicators to estimate the ISE-100 trends was investigated in this research. If the investigation findings show that these variables are efficient to explain the price movements in the ISE, then two basic judgments will be reached. Firstly, the EMH will be canceled or at least in a most optimistic view, a weak form efficiency in the market will be proven. Secondly, an investment decision support system based on NN estimates will be developed for investment advisors and investors. Also, the EMH is presented and contrasted with chaos theory and neural networks. This paper refutes the EMH based on previous neural network work. Finally, future directions for applying neural networks to the financial markets are discussed. Using statistical investigation we find causal relations between some indicators including macroeconomic, inflation, alternative financial instruments, and the Turkish Security Market. After adjusting seasonal and influationist impacts; input variable has been investigated their midterm relationship with ISE-100 Index. In the last section, appropriate normalization method for a backpropagation feedforward networks (BPNN) was researched. Keywords: Predicting stock indexes, artificial neural networks, financial markets forecasting parameters

Evaluation of calcium hydroxide removal efficiency of different irrigation techniques by microleakage assessment using Computerized Liquid Filtration method

Aim: To compare the efficiency of sonic irrigation, passive ultrasonic irrigation, and conventional syringe irrigation (CI) in removing pure and injectable calcium hydroxide (CH) from the root canals of mandibular second premolars by measuring the probable microleakage of residual CH particles in root canal obturation using computerized liquid filtration (CLF). Materials and Methods: Eighty instrumented mandibular second premolars were categorized into three experimental groups (n = 20 each) based on the irrigation method used for removing CH and a control group (n = 20) in which CH was not used. Each experimental group was divided into two equal groups (pure and injectable CH). After 1 week, CH was removed from the root canals, and the teeth were obturated. CLF measurements were performed 1 week after obturation. Nonparametric variables between two groups were compared using the Mann-Whitney U test, and the Kruskal-Wallis test was used to compare more than two groups. The significance level was set at p < 0.05. Results: All experimental groups showed higher leakage values than the control group. The highest leakage values were evident in the CI group, and the lowest leakage values were found in the sonic (EDDY) irrigation group. No significant differences were detected among the different forms of CH. Conclusions: None of the analyzed techniques could completely remove CH from root canals, resulting in higher leakage values. Sonic irrigation with EDDY was the best in removing CH from root canals

Evaluating the Effect of Different Laser Types on Dentin Fracture Resistance

Objectives: The aim of this in-vitro study was to evaluate the impact of the use of different laser types--particularly diode, Nd:YAG and Er:YAG--on dentin fracture resistance, with the assistance of fracture testing methods. Materials and Methods: Ninety human maxillary incisors were used. The teeth were divided into three experimental groups and three control groups, each of which included 15 samples. Group 1 had diode, group 2 had Nd:YAG, and group 3 had Er:YAG laser performed on them, after which they were dried and obturated using AH-Plus sealer and RevoS AS40 Gutta Percha (GP). Control group 1 was obturated just as in the experimental groups but without laser application; 2) control group was instrumented but not obturated; and 3) negative control group had no procedure performed at all. All the samples were fixed in acrylic blocks and had fracture tests performed on them using an Autograph Universal Testing Machine. The results were analyzed using IBM SPSS Statistics 22 software, the one-way ANOVA test and Tukey HDS (group identified that causes a difference) with significance

A guide to the use of bioassays in exploration of natural resources

This publication is based upon work from COST Action CA18238 (Ocean4Biotech), supported by COST (European Cooperation in Science and Technology) program . Funding Information: Research of Dina Simes was funded by the Portuguese National Funds from FCT—Foundation for Science and Technology , through projects UIDB/04326/2020 , UIDP/04326/2020 and LA/P/0101/2020 and AAC n° 41/ALG/2020 - Project n° 072583 – NUTRISAFE. Funding Information: Research of Evita Strode was supported by ERDF post-doctoral research grant 1.1.1.2/16/I/001 (application No 1.1.1.2/VIAA/3/19/465). Funding Information: Susana P. Gaudêncio: This work is financed by national funds from FCT - Fundação para a Ciência e a Tecnologia , I.P., in the scope of the project UIDP/04378/2020 and UIDB/04378/2020 of the Research Unit on Applied Molecular Biosciences - UCIBIO and the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy - i4HB . Funding Information: Research of Jerica Sabotič and Nika Janež was supported by Slovenian Research Agency ( J4- 2543 , J4-4555 , P4-0127 , P4-0432 ). Funding Information: Research of Anna Luganini and Giovanna Cristina Varese was financed by the University of Torino (Ricerca Locale) and the European Commission – NextGenerationEU , Project “Strengthening the MIRRI Italian Research Infrastructure for Sustainable Bioscience and Bioeconomy”, code n. IR0000005. Funding Information: Research of David Ezra was supported by The Chief Scientist of the Israeli Ministry of Agriculture and Rural Development (MOARD), grant number 20-02-0122 , and Copia Agro Israel. Publisher Copyright: © 2024 The AuthorsBioassays are the main tool to decipher bioactivities from natural resources thus their selection and quality are critical for optimal bioprospecting. They are used both in the early stages of compounds isolation/purification/identification, and in later stages to evaluate their safety and efficacy. In this review, we provide a comprehensive overview of the most common bioassays used in the discovery and development of new bioactive compounds with a focus on marine bioresources. We present a comprehensive list of practical considerations for selecting appropriate bioassays and discuss in detail the bioassays typically used to explore antimicrobial, antibiofilm, cytotoxic, antiviral, antioxidant, and anti-ageing potential. The concept of quality control and bioassay validation are introduced, followed by safety considerations, which are critical to advancing bioactive compounds to a higher stage of development. We conclude by providing an application-oriented view focused on the development of pharmaceuticals, food supplements, and cosmetics, the industrial pipelines where currently known marine natural products hold most potential. We highlight the importance of gaining reliable bioassay results, as these serve as a starting point for application-based development and further testing, as well as for consideration by regulatory authorities.publishersversionpublishe

Photoacclimation strategies in northeastern Atlantic seagrasses: Integrating responses across plant organizational levels

Seagrasses live in highly variable light environments and adjust to these variations by expressing acclimatory responses at different plant organizational levels (meadow, shoot, leaf and chloroplast level). Yet, comparative studies, to identify species' strategies, and integration of the relative importance of photoacclimatory adjustments at different levels are still missing. The variation in photoacclimatory responses at the chloroplast and leaf level were studied along individual leaves of Cymodocea nodosa, Zostera marina and Z. noltei, including measurements of variable chlorophyll fluorescence, photosynthesis, photoprotective capacities, non-photochemical quenching and D1-protein repair, and assessments of variation in leaf anatomy and chloroplast distribution. Our results show that the slower-growing C. nodosa expressed rather limited physiological and biochemical adjustments in response to light availability, while both species of faster-growing Zostera showed high variability along the leaves. In contrast, the inverse pattern was found for leaf anatomical adjustments in response to light availability, which were more pronounced in C. nodosa. This integrative plant organizational level approach shows that seagrasses differ in their photoacclimatory strategies and that these are linked to the species' life history strategies, information that will be critical for predicting the responses of seagrasses to disturbances and to accordingly develop adequate management strategies.Fundacao para a Ciencia e Tecnologia (FCT), Portugal [PTDC/MAR-EST/4257/2014

From the sea to aquafeed: A perspective overview

Aquaculture has been one of the fastest-growing food production systems sectors for over three decades. With its growth, the demand for alternative, cheaper and high-quality feed ingredients is also increasing. Innovation investments on providing new functional feed alternatives have yielded several viable alternative raw materials. Considering all the current feed ingredients, their circular adaption in the aquafeed manufacturing industry is clearly of the utmost importance to achieve sustainable aquaculture in the near future. The use of terrestrial plant materials and animal by-products predominantly used in aquafeed ingredients puts a heavily reliance on terrestrial agroecosystems, which also has its own sustainability concerns. Therefore, the aquafeed industry needs to progress with functional and sustainable alternative raw materials for feed that must be more resilient and consistent, considering a circular perspective. In this review, we assess the current trends in using various marine organisms, ranging from microorganisms (including fungi, thraustochytrids, microalgae and bacteria) to macroalgae and macroinvertebrates as viable biological feed resources. This review focuses on the trend of circular use of resources and the development of new value chains. In this, we present a perspective of promoting novel circular economy value chains that promote the re-use of biological resources as valuable feed ingredients. Thus, we highlight some potentially important marine-derived resources that deserve further investigations for improving or addressing circular aquaculture

Perspective: Measuring Sweetness in Foods, Beverages, and Diets: Toward Understanding the Role of Sweetness in Health.

Various global public health agencies recommend minimizing exposure to sweet-tasting foods or beverages. The underlying rationale is that reducing exposure to the perception of sweet tastes, without regard to the source of sweetness, may reduce preferences for sweetness, added sugar intake, caloric intake, and body weight. However, the veracity of this sequence of outcomes has yet to be documented, as revealed by findings from recent systematic reviews on the topic. Efforts to examine and document the effects of sweetness exposure are needed to support evidence-based recommendations. They require a generally agreed-upon methodology for measuring sweetness in foods, beverages, and the overall diet. Although well-established sensory evaluation techniques exist for individual foods in laboratory settings, they are expensive and time-consuming, and agreement on the optimal approach for measuring the sweetness of the total diet is lacking. If such a measure could be developed, it would permit researchers to combine data from different studies and populations and facilitate the design and conduct of new studies to address unresolved research questions about dietary sweetness. This narrative review includes an overview of available sensory techniques, their strengths and limitations, recent efforts to measure the sweetness of foods and diets across countries and cultures, and a proposed future direction for improving methods for measuring sweetness toward developing the data required to support evidence-based recommendations around dietary sweetness