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Ansa-effects in alkaline earth metal octaphenylmetallocenophanes and a derived ansa-ferrocene
No full textThe synthesis and structural characterisation of a series of alkaline earth ansa-octaphenylmetallocenes (Mg, Ca, Sr, Ba) bearing an ethylene bridge are described. The complexes [AE(C5Ph4CH2)2(thf)n] (AE = Mg (1), Ca (2) n = 1; AE = Sr (3), Ba (4), n = 2) were obtained through reductive dimerisation of 1,2,3,4-tetraphenylfulvene, facilitated by zero-valent metals and fully characterised by NMR spectroscopy. Single-crystal XRD studies reveal distinct binding differences of the Cp ligands to Mg in complex 1 compared to the heavier analogues (η3vs. η5). Complex 3 is the first structurally characterised ansa-metallocene complex of Sr. An ansa-effect was observed for the Ba complex 4 which showed good stability at room temperature in contrast to the previously described non-bridged analogue. Efficient transmetallation from the Ca ansa complex 2 to FeCl2 provided the new ansa-ferrocene complex [Fe(C5Ph4CH2)2] (5). Structural, spectroscopic and electrochemical properties of this bent ferrocenophane complex were compared to those of the known unbridged octaphenylferrocene
Differentiation of Fish Species Based on O-Acetylated N-Glycan Fragments Using LC-IM-MS to Combat Seafood Adulteration
No full textFood fraud poses a serious safety risk and affects the economy, with seafood being particularly vulnerable due to high species diversity and complex global supply chains. Accurate fish species identification is crucial for sustainable fishery management, food safety and protecting consumers with species-specific fish allergies who are at risk of life-threatening anaphylaxis. While some methods such as DNA-based PCR are well-established, they have limitations for processed foods and are costly, complex and time-consuming. Glycan markers are highly stable and have recently emerged as a tool for food authentication due to their unique species-specific characteristics. This study introduces N-glycan profiling as a novel technique for fish species authentication and addresses the need for reliable methods applicable to processed seafood products. By employing liquid chromatography ion mobility-mass spectrometry analysis, we examined N-glycan profiles of raw and heated fish muscle tissues from three fish species, which represent widely consumed seabass and snapper as well as their potential counterfeit substitute, tilapia from markets and restaurants. N-glycan structures containing different degrees of O-acetylated sialic acids (O-Ac-Sias) were identified as species-specific markers and clustering based on their percentage abundance enabled species classification. This study provides the foundation for the development of a rapid, species-specific authentication tool, which could be employed throughout the seafood supply chain, from harvest to retail, improving traceability and reducing mislabeling in markets and restaurants
The relation between mindset, social comparison, and academic engagement
No full textOne’s belief about intelligence (e.g., whether intelligence is malleable or fixed) impacts academic outcomes such as academic engagement. To examine exactly how this could take place, it is worth addressing the features of the academic setting, such as many opportunities to compare oneself with other students. Indeed, social comparison may affect the relation between belief in intelligence and academic engagement. We hypothesized that the belief that intelligence is malleable (i.e., growth mindset) would be positively associated with students’ academic engagement through social comparisons that are linked to comforting conclusions, while the belief that intelligence is fixed (i.e., fixed mindset) would be negatively associated with students’ academic engagement through social comparisons that are linked to threatening conclusions. The results demonstrated that growth mindset was positively associated with upward identification, one type of comforting social comparison, which was in turn positively associated with academic engagement. On the other hand, fixed mindset was positively associated with threatening social comparison. Based on the results, the relation between intelligence beliefs, social comparison types, and academic engagement are discussed
No rumen fermentation profiles and associated microbial diversities difference were found between Hu sheep and Karakul sheep fed a cottonseed hull diet
No full textBackground: This research aimed to investigate differences in rumen fermentation characteristics between Karakul sheep and Hu sheep reared under identical conditions. The test subjects included newborn Hu and Karakul sheep, which were monitored across three stages: stage I (Weaning period: 15 ~ 30 days), stage II (Supplementary feeding period: 31 ~ 90 days), and stage III (Complete feeding period: 91 ~ 150 days). During the supplementary feeding period, cottonseed hulls were the main roughage source. To analyze the dynamics of rumen fermentation, 16S rRNA sequencing and metabolomics methods were employed, alongside measurements of rumen fermentation parameters and cellulase activity. This comprehensive approach aimed to investigate the potential impact of breed on rumen fermentation indicators, microbial community structure, and metabolites in Hu and Karakul sheep.
Results: The 16S rRNA sequencing analysis revealed no significant differences in the relative abundance or dominant bacterial communities in the rumen across all stages. In stage II, rumen bacteria in both Hu and Karakul sheep were relatively stable. However, the Simpson index of Hu sheep in stage II was substantially greater than that of Karakul sheep, demonstrating similarities in the rumen microbial structure between stages II and III. Dynamic variations in fermentation parameters and cellulase activity in the rumen revealed that the indicators in both sheep breeds stabilized at 150 days. Metabolomic results revealed that the metabolic pathways in stage I were mainly concentrated in purine metabolism and lipid metabolism, while stage II was dominated by amino acid metabolism. Stage III involved mainly in pyrimidine and purine metabolism. An exploration of the relationships among rumen microbial biomarkers, key differentially abundant metabolites and rumen characteristics indicated that Karakul sheep exhibited superior lipid metabolism compared to Hu sheep.
Conclusion: These findings reveal that there were no interbreed differences in the rumen characteristics of Hu and Karakul sheep when fed the same cottonseed hull diet, despite differences in their metabolic pathways. The findings also indicate that the first 20 days represent the initial stage of rumen bacteria in Hu sheep, followed by a transition phase between 20 and 90 days, and a relatively stable stage from 90 to 150 days. These results provide a scientific basis for further understanding the rumen function of sheep and for optimizing their feeding strategies. D2CHRS7zryw_AWg9hJmKX2Video Abstrac
Fungal metabolite Ochratoxin A inhibits MrkD1P of multidrug-resistant Klebsiella pneumoniae: Integrated computational and in vitro validation
No full textMultidrug-resistant (MDR) Klebsiella pneumoniae poses a significant global health concern, particularly in hospital setting where it causes severe and hard-to-treat infections. In this study, 329 fungal-derived compounds were screened for their potential to inhibit MrkD1P, a key fimbrial adhesin protein (PDB ID: 3U4K) involved in host tissue adhesion. Molecular docking analysis identified ochratoxin A (− 9.1 kcal/mol), bromadiolone (− 8.6 kcal/mol), and permethrin (− 8.2 kcal/mol) as top-performing candidates, exhibiting strong binding affinities and stable molecular interactions, including hydrogen bonding and hydrophobic contacts. These findings were reinforced by 100-nanosecond molecular dynamics (MD) simulations, which showed sustained ligand–protein stability, particularly for ochratoxin A. Free energy estimations using the MM/PBSA method further suggested the thermodynamic favourability of these interactions. Pharmacokinetic profiling (ADMET) indicated favourable absorption and distribution properties for all three compounds, with low toxicity predictions, though some hepatotoxicity was noted. Principal component analysis (PCA) demonstrated that ochratoxin A and permethrin induced substantial alterations in protein dynamics, suggesting ligand-specific structural effects. Experimental validation confirmed the antibacterial activity of ochratoxin A against K. pneumoniae, producing a 34 ± 0.67 mm inhibition zone at 100 µg/disc, surpassing ciprofloxacin (33 mm) with a MIC of 18.33 ± 0.72 µg/mL and MBC of 39.33 ± 1.36 µg/mL (p < 0.05). Collectively, these in silico and in vitro results highlight fungal metabolites, particularly ochratoxin A, as promising therapeutic leads against MDR K. pneumoniae. However, further in vivo investigations are required to establish their safety and clinical potential
Marine shell from Walufeni Cave and the origins of the Kasua: Implications for Late Holocene socio-cultural interaction on the Great Papuan Plateau, Papua New Guinea
No full textThis paper presents new radiocarbon dates for the presence of marine shell at Walufeni Cave, dating from 3,250 cal BP. Walufeni Cave is located at the eastern end of the Great Papuan Plateau, Papua New Guinea, approximately 200 km in a straight line from the southern coast, thus the presence of marine shell here has significant implications for understanding changes in regional social dynamics during the Late Holocene. It is posited that the sudden appearance of marine shell at this time is linked to the spread of Austronesian influences along the southern coast of Papua New Guinea and Torres Strait—characterised by McNiven as the Coral Sea Cultural Interaction Sphere (CSCIS). Although largely modelled as a maritime system, we argue here that the CSCIS is linked to the movement of people and riverine exchange systems extending far into the interior
Menstrual health among young adults in Latin America and the Caribbean: A scoping review and evidence-gap map
No full textMenstrual health (MH) research has expanded in recent years, including studies throughout the reproductive life course. However, the experiences of young adults in Latin America and the Caribbean (LAC) remain comparatively underexplored, despite the importance of this life stage. The primary aim of this scoping review was to summarize and synthesize the literature on MH among young adults in the LAC region. Primary studies were included if they explored any aspect of MH among young adults aged 18–24 in university, health service, or community settings within LAC. Studies conducted in secondary school settings or involving specialized populations (e.g., elite athletes, incarcerated individuals) were excluded. Six electronic databases were searched for studies published between January 1, 1980 and October 23, 2024. Data were extracted and synthesized narratively, with key study characteristics summarized in tables. An interactive online evidence-gap map was developed to visualize geographic and thematic representation across the region. A total of 42 studies met the inclusion criteria, with most originating from Brazil (n = 21, 50%) and Mexico (n = 14, 33%). Studies were predominantly conducted in urban locations (n = 29, 69%), and all participants were described as female or women. Common MH experiences reported included menstrual cycle and bleeding characteristics (n = 16, 38%), dysmenorrhea (n = 13, 31%), and premenstrual syndrome (n = 10, 24%). Some studies indicated a negative impact of MH on academic participation (n = 5, 12%) and daily life activities (n = 16, 38%). The review identified significant geographic gaps, with only 21% (7/33) of LAC countries represented. This review highlights significant gaps in MH research among young adults in LAC, especially in rural areas and gender-diverse populations. There is a critical need for inclusive, region-specific research, initiatives, interventions and policies to enhance health, education and economic outcomes
Development of an internationally agreed national minimum dataset for low back pain: a modified Delphi study
No full textBACKGROUND
Low back pain is the leading cause of disability worldwide and the burden is expected to rise due to increases in ageing and population growth. The 2018 Lancet Low Back Pain Series proposed urgent actions to reverse the rising trend of disability due to low back pain including the need for a set of data indicators to routinely monitor progress in achieving these actions worldwide.
PURPOSE
To reach international consensus on a national minimum dataset of low back pain indicators that could be used across all countries to monitor progress in improving care and reducing disability from low back pain.
STUDY DESIGN
Modified Delphi study.
SAMPLE
Nineteen participants attended a preliminary workshop at the 2023 International Back and Neck Pain Forum, The Netherlands. Subsequently, 305 and 339 participants (researchers, clinicians, policy makers, educators, and consumers) completed Delphi surveys Rounds 1 and 2, respectively.
OUTCOME MEASURES
A 9-point Likert scale rated importance and feasibility of low back pain indicators (1 = not important or feasible; 9 = extremely important or feasible, 0 unsure). In Round 2, indicators that achieved consensus on importance and feasibility were ranked “most important” (top-ranked) to “least important.”
METHODS
Workshop participants were divided into four groups and asked to independently consider the importance and feasibility of 105 indicators identified from previous reviews divided into six themes. Participants could remove indicators considered unimportant or not feasible. This required unanimous agreement from independent workshop groups. Participants could also suggest improvements to the wording of indicators, the best unit of measure and additional missing indicators.
RESULTS
Thirty-eight indicators were recommended by workshop participants for inclusion in the Delphi study. Survey responses over two rounds reached consensus for 21 indicators (11 burden, 10 care) ranked from most to least important after reaching consensus on importance and feasibility in Round 1. Number of work days lost and number of opioid prescriptions for low back pain were the highest ranked indicators for burden and care, respectively. Importance rankings were similar across subgroups comparing high-income and low- and middle-income countries, and consumers and non-consumers.
CONCLUSION
We reached international consensus that 21 indicators could be used to monitor progress in improving care and outcomes for people with low back pain globally. Future work is needed to confirm the acceptability and feasibility of these indicators across countries, and, if implemented, to determine their value over time
Exploring the role of music listening in cultivating self-compassion
No full textMusic listening can impact emotional well-being. However, self-compassion, an aspect strongly related to emotional well-being, is rarely discussed in music listening literature. Therefore, this study explored self-compassionate and uncompassionate music listening experiences within the context of the COVID-19 pandemic. Two hundred and ninety-six Australian university students (Mage = 19.32) completed a mixed-methods music listening and self-compassion questionnaire. The questionnaire included the Self-Compassion Short Form Scale along with an author-adapted version exploring the influence of music listening. Additional, open-ended questions probed self-compassionate and uncompassionate music listening experiences. Most participants (81.76%) reported self-compassionate experiences through listening to music during the pandemic. Template analysis examining people’s self-compassionate and uncompassionate music listening experiences resulted in an overlap of themes including emotional experience, connection, and music styles. Distinct patterns were found, such as positive outcomes in self-compassionate responses and negative outcomes in uncompassionate experiences. The inclusion of emotional release within uncompassionate responses demonstrates the complexity of the relationship between music listening and self-compassion. These findings highlight the need for further exploration into music listening and self-compassion, particularly in an everyday context beyond the pandemic
AI-Optimized Autoencoder Architecture for Secure and Efficient Brain MRI Image Encryption and Compression on EDGE Platforms
No full textThe advancements in imaging techniques have improved the diagnostics in health care and medicine. The magnitude of MRI volumetric data sets remains a challenge with storage space, real-time processing, and communication, especially in edge computing environments that have limited resources. To tackle these issues, we suggest a new artificial intelligence-based optimisation of an autoencoder network architecture that combines spectral data augmentation with feature extraction using discrete wavelet transform on the brain MRI images for data compression and encryption. The system is optimised for edge deployment on NVIDIA Jetson TX2 platforms, allowing real-time processing at low power consumption. The proposed convolutional autoencoder encodes and decodes the MRI images while minimizing the reconstruction loss. It uses spectral data augmentation to improve overfitting and generalisation, while DWT further improves compression efficiency through multi-resolution feature extraction. The proposed model's compression performance and image reconstruction accuracy are evaluated with various parameters, achieving a compression ratio of 33.25 and a compression factor of 0.0625 with a mean squared error of 0.000445, a peak signal-to-noise ratio of 33.51 dB. Additionally, a structural similarity index of 0.9956 confirms that the model reconstructs images with a high preservation of detail, which is necessary for capturing critical diagnostic data. The deployment of the developed model on the NVIDIA Jetson TX2 GPU platform emphasizes computational efficiency and real-time execution, making the system suitable for telemedicine, remote diagnostics, and embedded AI healthcare applications