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Age-atratified reference ranges for directly measured serum free testosterone in community-dwelling and healthy men
No full textContext :
Direct measurement of serum free testosterone (FT) may help evaluate hypogonadism in men. However, to date, availability of reference ranges for measured FT (mFT) is limited.
Objective :
This work aimed to establish age-stratified reference ranges for mFT in healthy and community-dwelling adult men.
Methods :
Serum samples of 1202 White men were collected from large population cohort studies. FT was measured using equilibrium dialysis followed by liquid chromatography–tandem mass spectrometry (LC-MS/MS). Sex hormone–binding globulin was measured using immunoassay, and total testosterone was measured using LC-MS/MS. Reference ranges per age decade and for men aged 18 to 39 years with a body mass index (BMI) less than 30 were established following Clinical & Laboratory Standards Institute guidelines. Reference ranges were established as the 2.5th and 97.5th percentiles.
Results :
The reference range for mFT in healthy, nonobese men aged 18 to 39 years was 184 to 749 pmol/L. mFT levels showed a decrease with aging of −4.5 pmol/L per year. Having a BMI of 30 and 35 resulted in a decrease in mFT of 14.4% and 22.2%, respectively, compared to a reference BMI of 22.
Conclusion :
This study provides age-stratified reference ranges for mFT in adult men, established in the largest cohort to date, using published methodology. Our results also show that mFT levels are influenced by age and BMI. Future work should focus on whether age-stratified or reference ranges for young men should be employed, and how mFT can best be implemented in clinical practice including the improved application of calculated FT
Recovery without treatment as an underestimated and relational pathway to addiction recovery
No full textMany people affected by alcohol and other drug (AOD) challenges demonstrate remarkable resilience and strengths. The personal recovery movement has been instrumental in fostering hope and building on these strengths to support meaningful growth. Today, recovery is widely understood as multidimensional, integrative, strengths-based, and person-centered (Best & Lubman, 2012; Inanlou et al., 2020; Schrank & Slade, 2007; Whitley & Drake, 2010). It plays an important role in research, policy, and practice worldwide.
A key tenet of the recovery paradigm is that, because recovery is a deeply personal process, the pathways people follow are equally diverse (Kelly et al., 2017; SAMSHA, 2012). There is a growing recognition that recovery extends beyond the scope of acute treatment (Davidson et al., 2021; Sheedy & Whitter, 2013). Many people recover without engaging in formal treatment or mutual-aid services (Klingemann et al., 2010). Yet this pathway is mostly underrepresented, as most research focuses on treatment samples, leading to a skewed view of substance use problems and recovery (Granfield & Cloud, 1996; Humphreys, 2015).
Several factors explain why recovery without treatment has been undervalued. Practically, people who do not seek treatment are often considered “hard to reach” (Carballo et al., 2009). Socially, those who recover without formal support may remain invisible to researchers and practitioners, and thus receive little attention (Sobell, 2007). Paradigmatically, recovery without treatment challenges dominant medical models that frame addiction as a progressive brain disease requiring professional intervention (Klingemann et al., 2010). Ethically and politically, it has raised concerns about feeding into individualistic, moralistic views of recovery or undermining the rationale for treatment funding (Shaffer, 2007).
Nevertheless, research clearly shows that many people recover from serious substance use problems without treatment. Rather than reinforcing moralistic views, this pathway led to the development of the concept of recovery capital, now central to recovery-oriented thinking (Cloud & Granfield, 2008). Recovery capital emerged precisely from qualitative research with people in recovery without treatment (Granfield & Cloud, 1999; Granfield & Cloud, 2001). As part of the recovery movement’s broader aim to build and strengthen recovery resources in a holistic, ecological context, it offers a way to conceptualize the multiple domains that support long-term change (Hennessy, 2017).
Multiple scholars have argued that recovery requires a more relational perspective (Mudry et al., 2019; Price-Robertson et al., 2017; Topor et al., 2022). Recovery has been critiqued for both being professionalized despite its personal emphasis (De Ruysscher et al., 2019; Harper & Speed, 2014), and for being reinterpreted within a neoliberal framework (Topor et al., 2022). Research on recovery without treatment, beyond prevalence estimates, often continues to emphasize individualized narratives or indicators, with limited attention to the social and material contexts in which recovery unfolds. Yet the prevalence of “natural recovery” illustrates that recovery happens outside of treatment, embedded in everyday social, political, and material environments that are easily overlooked. More in-depth work is therefore needed to construct a balanced picture of recovery without treatment.
This project aims to advance and deepen a relational understanding of recovery without treatment, and by extension of recovery across pathways. Such an approach is both necessary and valuable for rethinking how substance use problems, recovery, and recovery support are understood and enacted.
To address this aim, the study was guided by four overarching research questions:
• What is the scope and what are the key characteristics of existing research on recovery without treatment? (RQ1)
• How do individuals in recovery without treatment differ from those who recover through formal or mutual-aid support (i.e. 'assisted' recovery)? (RQ2)
• How can the dynamics of recovery without treatment be understood from a relational perspective through first-person accounts? (RQ3)
• What are the implications of this understanding for recovery support across diverse recovery pathways? (RQ4
The effect of light, aeration and temperature on the growth and phenolic content of cultivated Ecklonia cava gametophytes (Phaeophyceae) and their antioxidant properties
No full textThis study investigates how selected environmental variables affect growth and total (poly)phenolic content (TPC) in the gametophyte stage of the brown kelp, Ecklonia cava, in controlled laboratory settings. In three multivariate cultivation experiments, we explored the effect of irradiance, aeration and temperature on the growth and TPC of both male and female gametophytes. Temperature did not cause significant changes in TPC content of female gametophytes, while for males grown at 15 °C significantly higher TPC levels were observed. We observed significant differences in TPC levels in both female and male gametophytes grown under different irradiances, while no effect of aeration was observed. In addition to their cytotoxicity, antioxidant activity of the polyphenolic extracts of female gametophytes was evaluated via two in vitro assays. First, all evaluated extracts displayed DPPH radical scavenging activity, ranging from approximately 22 – 59%, depending on the growth condition of the gametophytes. Second, induced intracellular oxidative stress in intestinal Caco-2 cells decreased significantly after exposure, compared with the control. From these results we conclude that TPC production in E. cava gametophytes is not aligned with optimal conditions for growth, influencing antioxidant activity, which could inform cultivation strategies for enhanced TPC levels. This study is a next step towards the development of the use and production of the bioactive compounds of E. cava and its potential use as a future marketable product
An AI-driven decision support system for product feature prioritization in software startups
No full textProduct feature prioritization is widely recognized as a critical challenge for software startups. Fast-paced environments, extreme
uncertainty, and limited resources often force these companies to make
trade-offs between competing ideas. Our study investigates the potential of an AI-based decision support system for feature prioritization in
the context of startups. We used a design science research methodology
to design, develop, and evaluate a proof of concept (PoC) artifact for
AI-based product feature prioritization. The artifact uses AI to make
decisions regarding product features using criteria such as return on investment, confidence, and time-to-value. We demonstrated and evaluated
this PoC artifact using semi-structured interviews with seven software
entrepreneurs. We analyzed the evaluation data using thematic analysis.
The evaluation results indicate that startups perceive the potential to
use AI to support the prioritization process. However, adoption depends
on improving transparency, explainability, interoperability, and usability
in these tools. The study contributes to the literature by providing early
insights into how AI-based tools for product feature prioritization are
perceived by startups
Comparative analysis of map-based site-specific mouldboard ploughing in silage maize cultivation
No full textTo eliminate soil compaction, farmers typically apply uniform, but aggressive tillage practices at maximum speed and depth. However, such an approach cannot efficiently address the spatial variability of soil compaction levels throughout a field. Therefore, site-specific tillage (SST) is expected to offer economic and environmental benefits by targeting compacted zones or layers. This study aims to evaluate, based on field experiments, the agronomic, economic and environmental performance of site-specific mouldboard ploughing (SS-MBP), using soil packing density (PD) maps measured by an on-line multi-sensor platform as input data for tillage recommendation calculations in two sandy-textured fields in Belgium both with silage maize. Each field was divided into three management zones having different PD, each of which was assigned a varying tillage speed. Stripe experiments were then carried out in these fields to compare the advantages and disadvantages of the SS-MBP treatments with uniform mouldboard ploughing (U-MBP). Results of this experiment showed that SS-MBP outperformed U-MBP in terms of reducing fuel consumption and CO2 emissions, increasing yield, and improving gross margins. SS-MBP treatments reduced fuel consumption by 15.4% to 25.9%, increased yield by 1.3% to 3.5% and improved gross margins by 23.25 to 59.74 /ha, compared to the U-MBP treatment in the two field experiments. Crucially, this study validates variable speed control of MBP as an acceptable ploughing practice by farmers than the variable depth approach proposed in earlier simulations. While these findings confirm the viability of SS-MBP for silage maize in sandy soils with low-to-medium degree of compaction, broader validation of the concept across diverse soil textures and crops is required to generalize the results reported in this work
Effect-based monitoring of emerging organic micropollutant mixtures in conventional wastewater treatment plant effluents in Flanders, Belgium
No full textWastewater treatment plants are recognized as major sources of organic micropollutants (OMPs) for aquatic environments. Yet, chemical monitoring alone may underestimate the ecological risks posed by complex OMP mixtures. Here, we combined an effect-based monitoring approach with targeted chemical analysis to assess environmental risks of OMP mixtures in effluents from 16 wastewater treatment plants in Flanders, Belgium. Effluent sites were selected from a five-year regional monitoring dataset, prioritizing locations with high cumulative risk quotients. Bioassays using Microcystis aeruginosa (cyanobacteria growth inhibition) and Danio rerio (zebrafish larvae, dark-light locomotive assay) were conducted on effluent extracts. High-resolution mass spectrometry identified 130 compounds, with 26 OMPs quantified across classes, including pharmaceuticals, antibiotics, herbicides, and per- and polyfluoroalkyl substances. Median and 10% effective concentrations for cyanobacteria inhibition ranged in relative enrichment factors of 4.1 to 38 and 1.1 to 4.7, respectively. Iceberg modeling identified azithromycin and clarithromycin as the main drivers of cyanobacterial inhibition. Zebrafish behavioral responses were significantly affected in 8 of 16 samples (relative enrichment factors, 1.25-20), but these differences could not be explained by the available chemical data. Only some suspect compounds were identified, including antidepressants and pesticides; therefore, this remains an interesting aspect for future investigations. Risk characterization for receiving surface waters using chemical-based risk quotients, margin of safety, and effect-based trigger values revealed ecological risk (risk quotient >1) in 13 of 16 sites. This study highlights the added value of integrating effect-based monitoring with chemical monitoring to explain mixture effects, identify key toxicants, and support improved regulatory frameworks for environmental management