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Risk in science : The socialization of risk-taking in early-career training
No full textScience is a risky business, and risk-taking is a critical disposition for scientists. This study uses a combination of survey and bibliometric data to measure the degree of individual scientists' risk-taking and investigate its determinants. In particular, we focus on academic training as a critical arena for the socialization of risk-taking and examine whether and how risk-taking is transmitted from one generation to the next. Drawing on a sample of PhD students and their supervisors in life sciences in Sweden, we find that students' risk-taking is significantly associated with that of their supervisors, and that this association is stronger when supervisors provide more frequent mentoring. Importantly, the association persists for 10 years even after students leave the PhD affiliation and switch research topics. Approximately 25 % of the variance in students' risk-taking can be attributed to the variance in supervisors' risk-taking. We find other determinants of students' risk-taking such as funding conditions and previous work experiences. As endogeneity due to selection is a concern, we employ the propensity score matching technique and obtained consistent results. We also exploit cases in which a supervisor was replaced by another supervisor, showing that the longer the initial supervisor is in place, the stronger the association is with the initial supervisor's risk-taking and the weaker with that of their replacement. These findings suggest the critical role of early-career academic training in shaping scientists' risk-taking and passing down the disposition to the next generation
Particle erosion wear in a high-pressure homogenizer – insights from DPM-CFD-erosion modelling
No full textHigh-pressure homogenizers (HPHs) are used extensively in food-, pharma-, and biotech processing. Erosion wear is a serious concern leading to high maintenance costs and downtime. Despite this, very little is known about how operating conditions and HPH design influence wear. Guidelines for optimizing design and operation are in great need. This contribution develops a relatively simple CFD-based approach to predict erosion wear in HPHs, with the long-term ambition of enabling model-based design and optimization. Comparison to previously published experimental data show that the model captures initial forcer wear. Moreover, the model is used to conclude on the effect of HPH seat inlet angle, particle properties, and operating conditions. The results suggest that erosion wear is reduced by using a lower seat inlet angle. Erosion wear also increases in proportion to the homogenizing pressure, which implies that care should be taken to design HPHs to reduce the utilized homogenizing pressure. The effects of (spherical) particle diameter and density on erosion are described in terms of a Stokes number; erosion wear is negligible if St < 1. Implications for the optimal design and operation of HPHs are discussed. As the first systematic investigation on erosion wear in HPH valves, the present numerical approach opens for improved design and operation of a unit operation with wide industrial application
Forensic differentiation of Malaysia biodiesel and illicit fuels using GC-FID and GC–MS techniques
No full textIllegal, unreported, and unregulated (IUU) fishing poses a serious threat to marine biodiversity and economic stability, particularly in coastal nations like Malaysia, where the smuggling of government-subsidized fuel is often linked to IUU activities. This study presents a forensic approach using gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC–MS) to chemically characterize and differentiate between legally distributed Malaysia biodiesel blends (B7 and B10) and illicit fuels seized from vessels involved in maritime violations. A total of 29 fuel samples from detained vessels in Kuala Terengganu and Mersing were compared with 20 reference biodiesel samples from major Malaysia fuel brands. GC-FID revealed hydrocarbon ranges of C10–C29 in biodiesel, with additional FAME peaks near n-C19 and n-C21, while IUU fuels showed wider ranges (C10–C33) but no FAMEs. GC–MS confirmed key biomarkers—bicyclic sesquiterpanes, adamantanes, isoprenoids, PAHs, and FAMEs—highlighting methyl palmitate (C16:0) and methyl oleate (C18:1) as diagnostic of biodiesel. Multivariate analyses (HCA and PCA) further separated B7, B10 and IUU samples, with subtle differences between B7 and B10 attributed to feedstock or blending variation. This study is the first to combine GC-FID, GC–MS, and chemometric analyses (PCA and HCA) into a forensic framework for differentiating Malaysian biodiesel blends (B7, B10) from illicit maritime fuels. By leveraging diagnostic biomarkers beyond FAMEs, the approach enables robust classification and provenance analysis. This integrated strategy provides evidential value for maritime law enforcement, advancing fuel forensics in Southeast Asia. These findings display the utility of chromatographic techniques in maritime law enforcement, enabling fuel source attribution and supporting legal proceedings. Despite promising results, limitations such as restricted sample coverage, lack of replicate analysis, and absence of a chromatographic fingerprint database highlight the need for further validation. The study advocates for the development of an integrated GC-based forensic framework to enhance Malaysia's capability in combatting fuel smuggling and IUU fishing activities
Future projections of wet and dry spells in southern Sweden : The impact of climate model resolution
No full textThis study evaluates how well five Regional Climate Model (RCM) projections at resolutions from 44 km to 3 km reproduce wet and dry spells compared with observations at six locations in Scania, southern Sweden. Future changes in general and extreme wet and dry signals were also analyzed under RCP8.5 to the end of the 21st century. Convection-permitting climate models (CPMs), operating at resolutions fine enough to explicitly resolve convective processes (< 4 km), are widely recognized to simulate precipitation characteristics more accurately than coarser models. Our results confirm that CPM AROME (3 km), outperforms coarser RCMs in representing both wet and dry spells. Future projections across all resolutions indicate increases in wet spells to the end of the century, with average daily precipitation increasing by 8–12 %. The number of wet events, their average depth, and duration also projected to increase to varying degrees. For dry spells, the annual number of dry days shows a slight increase (0–3 %). The number of dry events is projected to decrease while both the average duration and the annual maximum consecutive dry days increase. Extreme value analysis shows that extreme precipitation intensities at various accumulating durations increase over 5- to 50-year return periods, as implied by the Wet Climate Factor (WCF). The Dry Climate Factor (DCF) indicates shorter annual maximum consecutive dry days in the near future, but prolonged at the end of the century by 3–9 %. These findings corroborate with previous research and improve understanding of systematic biases across RCMs resolutions. They further suggest that CPMs offer improved reliability in projecting future variability in wet and dry conditions, with important implications for regional climate services
Pregnancy blood pressure trajectories in relation to high PFAS exposure : A longitudinal study from the Ronneby Mother-Child Cohort
No full textINTRODUCTION: Maternal blood pressure (BP) is crucial for the health of both mother and fetus, with long-term implications for the child's health. Studies exploring the link between perfluoroalkyl substances (PFAS) exposure and hypertensive disorders of pregnancy often yield inconsistent results, frequently focusing on a single BP measurement rather than longitudinal measurements. This study characterized the systolic and diastolic BP trajectories during pregnancy and determined their association with PFAS exposure in Ronneby, Sweden, where a third of the population was highly exposed from contaminated drinking water.METHODS: We used longitudinal data from the Ronneby Mother-Child Cohort. Nine PFAS compounds were measured in a serum sample collected during pregnancy and BP measurements were taken as part of the routine pregnancy monitoring program. BP trajectories were identified by Group Based Trajectory Modelling. Odds ratios (OR) for membership in each trajectory by PFAS quartiles were calculated via multinomial logistic regression models and Quantile G-computation was applied to quantify the joint effect of PFAS.RESULTS: The study comprised 214 women with 1705 BP measurements. PFOS and PFHxS were detected at the highest concentrations (medians 16.6 and 10.2 ng/mL). Trajectory analysis identified a cubic shape three-trajectory solution, with one trajectory having elevated BP throughout pregnancy. Higher PFAS concentrations seemed to increase the probability of belonging to the high-BP trajectory in both single-pollutant and multi-pollutant models.CONCLUSIONS: Higher PFAS exposure was associated with an increased OR of an adverse BP trajectory, underscoring the importance of monitoring pregnancy BP in communities with elevated PFAS exposures
A truncated CDC14A retains catalytic structure and phosphatase activity preserving male fertility but causes nonsyndromic deafness
No full textPathogenic variants of human CDC14A (cell division cycle 14A) are associated either with nonsyndromic deafness DFNB32 or HIIMS, hearing impairment infertile male syndrome. The 623-residue CDC14A protein has two globular domains (residues 17-152 and 217-325) and a 278-residue C-terminal intrinsically disordered region (IDR). To date, 16 recessive variants of human CDC14A are associated with hearing loss. Variants affecting the globular N-terminal domains of human CDC14A are associated with HIIMS while mutations in the IDR cause nonsyndromic deafness DFNB32. Here, we tested the hypothesis that human CDC14A c.1033C>T variant, segregating with nonsyndromic deafness in family PKSN10, introduces a premature translation stop codon (p.R345X) yet the mRNA escapes nonsense-mediated decay (NMD) and produces sufficient active phosphatase to allow for male fertility. Quantitative analyses of CDC14A mRNA in blood leukocytes from PKSN10 family showed CDC14A transcripts are stable including homozygous (p.R345X) transcripts which evade NMD. To further test this hypothesis, we performed biochemical and structural characterizations of truncated CDC14A (ΔC-CDC14A) protein retaining only residues 1 to 345. Kinetic functional studies and X-ray crystallographic findings of purified ΔC-CDC14A protein indicate that it retains structural integrity and phosphatase activity. Molecular genetic reports of DFNB32 and HIIMS, taken together with structural and functional data in this study, indicate that phosphatase activity of ΔC-CDC14A containing the two globular domains is sufficient for male fertility but insufficient for normal hearing. In addition, we show that the C-terminal IDR of CDC14A is required for normal hearing, likely because it is necessary for normal localization of CDC14A in hair cells
Du dansar, bleka ungdom : Lundastudenterna och jazzen under ”det glada tjugotalet”
No full textGenomgång av hur den nya musikformen jazz mottogs bland Lunds studenter speglat i bl a tidningen Lundagåd, i samtida dagspressnotiser om arrangemang i studentvärlden och genom bevarade dansprogram från studentikosa festligheter
