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Technological support options for the usage of Brazilian Açaí berries in the European Food Market
(2022)
The highly perishable fruit açaí grows on palm trees in northern Brazil and is colloquially known as a berry with high nutritional value. The seed of the drupe makes up around 85 percent of the fruits weight and only the pulp around the seed is used for human consumption. The manufacturing step after harvest includes the pulping and the preservation of the fruit. The preservation step is necessary, because the açaí pulp contains a high microbial load. There are several preservation processes including the use of chlorinated or ozonated water, alcoholic fermentation, pasteurization, freezing or dehydration. Those techniques are overall not very gentle and have the potential to leave residues in the final product, which can change its typical sensorial characteristics. Therefore, an experiment was conducted, to see if a relatively new gentle preservation method called PEF can reduce the microbial load in an açaí- smoothie.
For this purpose, a PEF-machine was built and verified based on the paper from HEINZ ET AL. [2003]. The self-built machine works efficiently, when there is a reduction of microorganisms like Escherichia coli in apple juice due to the induced Pulsed Electric Fields. If this is the case, the described experiment with açaí-smoothie can be carried out with the self-built PEF- machine. In this experiment the results of the validation of this PEF-machine were not comparable to those from the paper from HEINZ ET AL. [2003]. So, the self-built PEF-machine in Brazil did not work sufficiently. Hence, the experiment which should show that a reduction of microorganisms, such as Escherichia coli, in açaí-smoothie with PEF is possible, was performed in Germany. It was accrued out at ELEA with using the PEFPilotTM Dual. This experiment confirmed the assumption, that microorganisms can be reduced in açaí-smoothie with PEF. Escherichia coli was reduced by 2 logs, Saccharomyces cerevisiae by 3 logs and Lactobacillus plantarum by 6 logs. And a comparison between PEF and the known preservation methods for açaí showed that it can be a compatible alternative.
Moreover, the topic, how açaí fits into the European Food Market is answered within this paper. When offering açaí food products to the European population, ideas can be originated from the well-working Brazilian market. It can be helpful to mix açaí with known European fruits for a better acceptance by the people. Then açaí can help to meet the Europeans needs of the current time for fresh and healthy food, especially when preserved with PEF. Furthermore, it is important to work towards a sustainable supply chain system from the cultivation until the unloading at the destination in Europe. Sustainability is important for the integration in the European market, not only for environmental protection, but also in terms of social stability and marketing purposes. In addition, access requirements, further food-related regulations, and the seasonality of açaí present a major hurdle.
Building on this thesis, further papers shall be written, not only in the field of the preservation of the açaí pulp with PEF, but also in the direction of combined preservation methods for açaí, the sustainable usage of the açaí seeds, product innovations containing the Brazilian fruit or various market research.
Background
A peripheral venous catheter (PVC) is the most widely used device for obtaining vascular access, allowing the administration of fluids and medication. Up to 25% of adult patients, and 50% of pediatric patients experience a first-attempt cannulation failure. In addition to patient and clinician characteristics, device features might affect the handling and success rates. The objective of the study was to compare the first-attempt cannulation success rate between PVCs with wings and a port access (Vasofix® Safety, B. Braun, abbreviated hereon in as VS) with those without (Introcan® Safety, B. Braun, abbreviated hereon in as IS) in an anesthesiological cohort.
Methods
An open label, multi-center, randomized trial was performed. First-attempt cannulation success rates were examined, along with relevant patient, clinician, and device characteristics with univariate and multivariate analyses. Information on handling and adherence to use instructions was gathered, and available catheters were assessed for damage.
Results
Two thousand three hundred four patients were included in the intention to treat analysis. First-attempt success rate was significantly higher with winged and ported catheters (VS) than with the non-winged, non-ported design (IS) (87.5% with VS vs. 78.2% with IS; PChi < .001). Operators rated the handling of VS as superior (rating of “good” or “very good: 86.1% VS vs. 20.8% IS, PChi < .001). Reinsertion of the needle into the catheter after partial withdrawal—prior or during the catheterization attempt—was associated with an increased risk of cannulation failure (7.909, CI 5.989–10.443, P < .001 and 23.023, CI 10.372–51.105, P < .001, respectively) and a twofold risk of catheter damage (OR 1.999, CI 1.347–2.967, P = .001).
Conclusions
First-attempt cannulation success of peripheral, ported, winged catheters was higher compared to non-ported, non-winged devices. The handling of the winged and ported design was better rated by the clinicians. Needle reinsertions are related to an increase in rates of catheter damage and cannulation failure.
During gestation, the most drastic change in oxygen supply occurs with the onset of ventilation after birth. As the too early exposure of premature infants to high arterial oxygen pressure leads to characteristic diseases, we studied the adaptation of the oxygen sensing system and its targets, the hypoxia-inducible factor- (HIF-) regulated genes (HRGs) in the developing lung. We draw a detailed picture of the oxygen sensing system by integrating information from qPCR, immunoblotting, in situ hybridization, and single-cell RNA sequencing data in ex vivo and in vivo models. HIF1α protein was completely destabilized with the onset of pulmonary ventilation, but did not coincide with expression changes in bona fide HRGs. We observed a modified composition of the HIF-PHD system from intrauterine to neonatal phases: Phd3 was significantly decreased, while Hif2a showed a strong increase and the Hif3a isoform Ipas exclusively peaked at P0. Colocalization studies point to the Hif1a-Phd1 axis as the main regulator of the HIF-PHD system in mouse lung development, complemented by the Hif3a-Phd3 axis during gestation. Hif3a isoform expression showed a stepwise adaptation during the periods of saccular and alveolar differentiation. With a strong hypoxic stimulus, lung ex vivo organ cultures displayed a functioning HIF system at every developmental stage. Approaches with systemic hypoxia or roxadustat treatment revealed only a limited in vivo response of HRGs. Understanding the interplay of the oxygen sensing system components during the transition from saccular to alveolar phases of lung development might help to counteract prematurity-associated diseases like bronchopulmonary dysplasia.
Objectives: To measure and assess the economic impact of adherence to a single quality indicator (QI) regarding weaning from invasive ventilation.
Design: Retrospective observational single-centre study, based on electronic medical and administrative records.
Setting: Intensive care unit (ICU) of a German university hospital, reference centre for acute respiratory distress syndrome.
Participants: Records of 3063 consecutive mechanically ventilated patients admitted to the ICU between 2012 and 2017 were extracted, of whom 583 were eligible adults for further analysis. Patients’ weaning protocols were evaluated for daily adherence to quality standards until ICU discharge. Patients with <65% compliance were assigned to the low adherence group (LAG), patients with ≥65% to the high adherence group (HAG).
Primary and secondary outcome measures: Economic healthcare costs, clinical outcomes and patients’ characteristics.
Results: The LAG consisted of 378 patients with a median negative economic results of −€3969, HAG of 205 (−€1030), respectively (p<0.001). Median duration of ventilation was 476 (248; 769) hours in the LAG and 389 (247; 608) hours in the HAG (p<0.001). Length of stay (LOS) in the LAG on ICU was 21 (12; 35) days and 16 (11; 25) days in the HAG (p<0.001). LOS in the hospital was 36 (22; 61) days in the LAG, and within the HAG, respectively, 26 (18; 48) days (p=0.001).
Conclusions: High adherence to this single QI is associated with better clinical outcome and improved economic returns. Therefore, the results support the adherence to QI. However, the examined QI does not influence economic outcome as the decisive factor.
This qualitative study focuses on assessing the “future readiness” capacity of three Peruvian Higher Education Institutions under the HEInnovate framework. The main question guiding this research is: To what extent can Peruvian universities be considered entrepreneurial and ready
for tackling the Challenges of the Future? The Challenges of the Future are understood as the challenges generated by concepts such as The Future of Work, The Global Skills Gap, Employability and unexpected and destabilizing risks of the environment, such as COVID-19.
Universities were studied based on 4 research sub-questions: 1) How do Peruvian HEIs rate in Entrepreneurial Capacity according to the HEInnovate framework? 2) What are the factors supporting or preventing Peruvian HEIs to accomplish their entrepreneurial potential? 3) What efforts are Peruvian HEIs making for developing 21st century skills, accomplishing Digital Transformation, and enhancing their students Employability? and 4) What measures could Peruvian HEIs take in order to maximize their entrepreneurial and future-proof potential? The research methodology used was mixed, applying first a quantitative assessment, and then
complementing the results with in-depth interviews. After presenting the conclusions, recommendations for policy action and for university management are given.
"The limits of my language are the limits of my mind. All I know is what I have words for" (Wittgenstein). When learning something completely new, we connect the unknown term to an already existing part of our knowledge. We can only build new ideas and insights upon an existing conceptual foundation. In the field of statistics, we educators frequently find ourselves met with great confusion when teaching novices. These students, entirely unfamiliar with even basic statistics, must connect the introduced statistical terms within their personal existing networks of largely non-statistical knowledge. Lecturers, on the other hand, who are well versed in statistics, have deeply internalized the content to be taught and its relevant context. The juxtaposition of the two roles may produce amusement in a lecturer upon gaining insight into the word associations made by the statistical novices. For example, a ‘logistic regression’ does not involve the ‘shipping of goods in economically difficult times,’ though this might seem entirely reasonable and intuitive to the statistics learner. Other times, these different perspectives can lead to headaches and frustration for both learners and their lecturers. In this article, we illustrate how simple statistical terms are initially connected to a student’s pre-exiting knowledge and how these associations change after completing an introductory course in applied statistics. Furthermore, we emphasize the important difference between “term”, “approach”, and “context”. Understanding this fundamental distinction may help improve the communication between the lecturer and the learner. We offer a collection of practical tools for instructors to help promote students’ conceptual understanding in a supportive, mutually-beneficial learning environment.
Background
In mucosal barrier interfaces, flexible responses of gene expression to long-term environmental changes allow adaptation and fine-tuning for the balance of host defense and uncontrolled not-resolving inflammation. Epigenetic modifications of the chromatin confer plasticity to the genetic information and give insight into how tissues use the genetic information to adapt to environmental factors. The oral mucosa is particularly exposed to environmental stressors such as a variable microbiota. Likewise, persistent oral inflammation is the most important intrinsic risk factor for the oral inflammatory disease periodontitis and has strong potential to alter DNA-methylation patterns. The aim of the current study was to identify epigenetic changes of the oral masticatory mucosa in response to long-term inflammation that resulted in periodontitis.
Methods and results
Genome-wide CpG methylation of both inflamed and clinically uninflamed solid gingival tissue biopsies of 60 periodontitis cases was analyzed using the Infinium MethylationEPIC BeadChip. We validated and performed cell-type deconvolution for infiltrated immune cells using the EpiDish algorithm. Effect sizes of DMPs in gingival epithelial and fibroblast cells were estimated and adjusted for confounding factors using our recently developed “intercept-method”. In the current EWAS, we identified various genes that showed significantly different methylation between periodontitis-inflamed and uninflamed oral mucosa in periodontitis patients. The strongest differences were observed for genes with roles in wound healing (ROBO2, PTP4A3), cell adhesion (LPXN) and innate immune response (CCL26, DNAJC1, BPI). Enrichment analyses implied a role of epigenetic changes for vesicle trafficking gene sets.
Conclusions
Our results imply specific adaptations of the oral mucosa to a persistent inflammatory environment that involve wound repair, barrier integrity, and innate immune defense.
Background
In DNA methylation analyses like epigenome-wide association studies, effects in differentially methylated CpG sites are assessed. Two kinds of outcomes can be used for statistical analysis: Beta-values and M-values. M-values follow a normal distribution and help to detect differentially methylated CpG sites. As biological effect measures, differences of M-values are more or less meaningless. Beta-values are of more interest since they can be interpreted directly as differences in percentage of DNA methylation at a given CpG site, but they have poor statistical properties. Different frameworks are proposed for reporting estimands in DNA methylation analysis, relying on Beta-values, M-values, or both.
Results
We present and discuss four possible approaches of achieving estimands in DNA methylation analysis. In addition, we present the usage of M-values or Beta-values in the context of bioinformatical pipelines, which often demand a predefined outcome. We show the dependencies between the differences in M-values to differences in Beta-values in two data simulations: a analysis with and without confounder effect. Without present confounder effects, M-values can be used for the statistical analysis and Beta-values statistics for the reporting. If confounder effects exist, we demonstrate the deviations and correct the effects by the intercept method. Finally, we demonstrate the theoretical problem on two large human genome-wide DNA methylation datasets to verify the results.
Conclusions
The usage of M-values in the analysis of DNA methylation data will produce effect estimates, which cannot be biologically interpreted. The parallel usage of Beta-value statistics ignores possible confounder effects and can therefore not be recommended. Hence, if the differences in Beta-values are the focus of the study, the intercept method is recommendable. Hyper- or hypomethylated CpG sites must then be carefully evaluated. If an exploratory analysis of possible CpG sites is the aim of the study, M-values can be used for inference.
Background
Postoperative delirium (POD) and postoperative cognitive dysfunction (POCD) are frequent and serious complications after surgery. We aim to investigate the association between genetic variants in cholinergic candidate genes according to the Kyoto encyclopedia of genes and genomes - pathway: cholinergic neurotransmission with the development of POD or POCD in elderly patients.
Methods
This analysis is part of the European BioCog project (www.biocog.eu), a prospective multicenter observational study with elderly surgical patients. Patients with a Mini-Mental-State-Examination score ≤ 23 points were excluded. POD was assessed up to seven days after surgery using the Nursing Delirium Screening Scale, Confusion Assessment Method and a patient chart review. POCD was assessed three months after surgery with a neuropsychological test battery. Genotyping was performed on the Illumina Infinium Global Screening Array. Associations with POD and POCD were analyzed using logistic regression analysis, adjusted for age, comorbidities and duration of anesthesia (for POCD analysis additionally for education). Odds ratios (OR) refer to minor allele counts (0, 1, 2).
Results
745 patients could be included in the POD analysis, and 452 in the POCD analysis. The rate of POD within this group was 20.8% (155 patients), and the rate of POCD was 10.2% (46 patients). In a candidate gene approach three genetic variants of the cholinergic genes CHRM2 and CHRM4 were associated with POD (OR [95% confidence interval], rs8191992: 0.61[0.46; 0.80]; rs8191992: 1.60[1.22; 2.09]; rs2067482: 1.64[1.10; 2.44]). No associations were found for POCD.
Conclusions
We found an association between genetic variants of CHRM2 and CHRM4 and POD. Further studies are needed to investigate whether disturbances in acetylcholine release and synaptic plasticity are involved in the development of POD.
A comparison study on modeling of clustered and overdispersed count data for multiple comparisons
(2021)
Data collected in various scientific fields are count data. One way to analyze such data is to compare the individual levels of the factor treatment using multiple comparisons. However, the measured individuals are often clustered – e.g. according to litter or rearing. This must be considered when estimating the parameters by a repeated measurement model. In addition, ignoring the overdispersion to which count data is prone leads to an increase of the type one error rate. We carry out simulation studies using several different data settings and compare different multiple contrast tests with parameter estimates from generalized estimation equations and generalized linear mixed models in order to observe coverage and rejection probabilities. We generate overdispersed, clustered count data in small samples as can be observed in many biological settings. We have found that the generalized estimation equations outperform generalized linear mixed models if the variance-sandwich estimator is correctly specified. Furthermore, generalized linear mixed models show problems with the convergence rate under certain data settings, but there are model implementations with lower implications exists. Finally, we use an example of genetic data to demonstrate the application of the multiple contrast test and the problems of ignoring strong overdispersion.