Relative Occupancy Research Articles

The histone chaperones ASF1 and HIRA are required for telomere length and 45S rDNA copy number homeostasis.

Genome stability is significantly influenced by the precise coordination of chromatin complexes that facilitate the loading and eviction of histones from chromatin during replication, transcription, and DNA repair processes. In this study, we investigate the role of the Arabidopsis H3 histone chaperones ANTI-SILENCING FUNCTION 1 (ASF1) and HISTONE REGULATOR A (HIRA) in the maintenance of telomeres and 45S rDNA loci, genomic sites that are particularly susceptible to changes in the chromatin structure. We find that both ASF1 and HIRA are essential for telomere length regulation, as telomeres are significantly shorter in asf1a1b and hira mutants. However, these shorter telomeres remain localized around the nucleolus and exhibit a comparable relative H3 occupancy to the wild type. In addition to regulating telomere length, ASF1 and HIRA contribute to silencing 45S rRNA genes and affect their copy number. Besides, ASF1 supports global heterochromatin maintenance. Our findings also indicate that ASF1 transiently binds to the TELOMERE REPEAT BINDING 1 protein and the N terminus of telomerase in vivo, suggesting a physical link between the ASF1 histone chaperone and the telomere maintenance machinery.

Barn owl site occupancy and breeding success in relation to land use and nest box characteristics

AbstractAgricultural landscapes play a crucial role in enhancing biodiversity because of their widespread presence over the Earth and their ability to encompass diverse ecosystems. Recognizing this, numerous governments are incentivizing farmers through direct payments to adopt sustainable practices, such as managing extensive pastures and meadows, planting wildflowers, or establishing hedgerows. However, the benefit of such sustainable practices on vertebrate species is not well understood. From 2018 to 2020, we investigated nest occupancy, fledging success, and clutch size of a Swiss population of barn owls (Tyto alba) with respect to nest box characteristics and the presence of extensive agriculture and urbanization in areas surrounding nest boxes. Our results revealed that extensively used pastures were positively associated with site occupancy but negatively associated with clutch size. The proportion of urban areas was negatively related to both site occupancy and clutch size. The altitude of the nest box location was negatively correlated with occupancy, and the number of nest boxes placed at the same site (either 1 or 2) was positively correlated with site occupancy. Moreover, clutch size, but not fledging success, was larger in nest boxes placed outside barns than in nest boxes placed inside barns. Based on these findings, we recommend installing nest boxes at locations <700 m in altitude and in pairs on the same barn, incorporating biodiversity promotion areas into agricultural landscapes, and avoiding dense urban areas in favor of rural zones with lower urban density. Understanding the nuanced relationships between nest box characteristics, environmental factors, and breeding success provides valuable insights for optimizing artificial nesting sites and enhancing the overall reproductive success of barn owls.

Automated model-free analysis of cryo-EM volume ensembles with SIREn.

Cryogenic electron microscopy (cryo-EM) has the potential to capture snapshots of proteins in motion and generate hypotheses linking conformational states to biological function. This potential has been increasingly realized by the advent of machine learning models that allow 100s-1,000s of 3D density maps to be generated from a single dataset. How to identify distinct structural states within these volume ensembles and quantify their relative occupancies remain open questions. Here, we present an approach to inferring variable regions directly from a volume ensemble based on the statistical co-occupancy of voxels, as well as a 3D-convolutional neural network that predicts binarization thresholds for volumes in an unbiased and automated manner. We show that these tools recapitulate known heterogeneity in a variety of simulated and real cryo-EM datasets, and highlight how integrating these tools with existing data processing pipelines enables improved particle curation and the construction of quantitative conformational landscapes.

Fueling the Firefighter and Tactical Athlete with Creatine: A Narrative Review of a Key Nutrient for Public Safety

Background/Objectives: Firefighters, tactical police officers, and warriors often engage in periodic, intermittent, high-intensity physical work in austere environmental conditions and have a heightened risk of premature mortality. In addition, tough decision-making challenges, routine sleep deprivation, and trauma exacerbate this risk. Therefore, identifying strategies to bolster these personnel’s health and occupational performance is critical. Creatine monohydrate (CrM) supplementation may offer several benefits to firefighters and tactical athletes (e.g., police, security, and soldiers) due to its efficacy regarding physical performance, muscle, cardiovascular health, mental health, and cognitive performance. Methods: We conducted a narrative review of the literature with a focus on the benefits and application of creatine monohydrate among firefighters. Results: Recent evidence demonstrates that CrM can improve anaerobic exercise capacity and muscular fitness performance outcomes and aid in thermoregulation, decision-making, sleep, recovery from traumatic brain injuries (TBIs), and mental health. Emerging evidence also suggests that CrM may confer an antioxidant/anti-inflammatory effect, which may be particularly important for firefighters and those performing tactical occupations exposed to oxidative and physiological stress, which can elicit systemic inflammation and increase the risk of chronic diseases. Conclusions: This narrative review highlights the potential applications of CrM for related tactical occupations, with a particular focus on firefighters, and calls for further research into these populations.

Who's behind the wheel? Work and health backgrounds of new transit bus operators.

Investigate new bus operators' (n = 293) occupational and health backgrounds to inform how transit authorities can support their future health and job success. New bus operators completed surveys and direct measurements that addressed demographics, work history, and 10 health risk factors. Participants averaged 42.76 years of age and were predominantly male (73.5%). Many (45.7%) came from minority backgrounds and most (66.3%) had no prior commercial driving experience. Transportation and material moving occupations were operators' most common prior jobs followed by protective service and sales and related occupations. Study-specific criteria classified operators as having low (49.5%), medium (37.9%), and high (12.6%) health risk levels. About half of the sample had medium-to-high health risks and most lacked commercial driving experience. Such information may help employers proactively support new bus operators' health and job success.

The congruence between the preferred and actual places of death among terminal cancer patients in China.

Dying in a preferred place is important for a good death. Currently, no study has evaluated the extent to which the preferences for the place of death (PoD) are met among terminal cancer patients in China. This study examined the congruence between the preferred and actual PoD and its predictors among terminal cancer patients in China. Between 2015 and 2023, 845 terminal cancer patients from four tertiary hospitals in Wuhan, China, were enrolled and followed till death. Face-to-face surveys at baseline and telephone-based interviews in the last month of patients' lives were combined to learn patients' preferred PoD. Data on patients' actual PoD were collected from families within 1 month after patients' death. Of the 410 patients who died, 62.7% of them died in hospitals. The agreement between patients' preferred and actual PoD was fair (κ = 0.221). The congruence between patients' preferred and actual PoD was 63.0, 36.6%, and 0 for hospital death, home death, and hospice facility/nursing home death separately. Patients were more likely to die in their preferred places if their preferred place and family caregivers' belief of patients' preferred PoD was congruent (odds ratio [OR] = 6.464, p = 0.001), or if caregivers had a medically related occupation (OR = 4.577, p = 0.003); if patients were hospitalized at least twice in the last month of life (OR = 0.422, p = 0.000), or the quality of care received by patients in the last 48 h was rated good by the families (OR = 0.373, p = 0.011), patients were less likely to die in their preferred places. The congruence between patients' preferred and actual PoD was fair. Advance care planning (ACP) needs to be popularized in China, and the quality of care in hospice facilities and nursing homes should be improved. The necessary policy support for hospice care should be made to respect cancer patients' end-of-life (EoL) care preferences in China.

Population response of eastern wild turkey to removal of wild pigs

AbstractThere is insufficient understanding of interspecific interactions with the eastern wild turkey (Meleagris gallopavo silvestris) and wild pigs (Sus scrofa). Wild pigs compete with wild turkeys and predate nests and adults; however, population‐level effects on wild turkeys are not clear. Using cameras, we assessed responses of wild turkey populations to wild pig removal in central Alabama, USA, from 2018–2021. We compared wild turkey relative abundance and occupancy on 3 large‐scale pig‐removal treatment sites (3,407–5,531 ha) relative to a control site (2,510 ha) during 1 pre‐treatment year and 2 post‐treatment years, with analyses including a covariate expressing the cumulative number of pigs removed from each site standardized by the initial pig abundance on the site. We removed 1,851 wild pigs from the 3 treatment sites over 22 months. Based on N‐mixture modeling, when the number of pigs removed was equal to our baseline population estimates (i.e., 100% removal relative to initial population), there were 1.50 (95% CL = 1.01–2.23) times as many wild turkeys, and detection of wild turkeys was 2.01 (95% CL = 1.49–2.70) times as likely. Additionally, poults were 3.49 (95% CL = 1.12–10.89) times as likely to occupy an area when the number of pigs removed was equal to our baseline population estimates compared with poult occupancy at baseline pig abundance. Our data suggests that reduction of wild pig populations may lead to a localized increase in populations of wild turkeys.

Work-related factors and occupations in relation to the incidence of type 2 diabetes: an exploratory study among 274,716 Dutch workers

Work-related factors and occupations in relation to the incidence of type 2 diabetes: an exploratory study among 274,716 Dutch workers

Prevalence and burden of asthma among US working adults by industry and occupation—United States, 2020–2021

Objectives Assess the prevalence of current asthma, asthma attacks/episodes, and asthma-related emergency room (ER) visits by industry and occupation and estimate the proportion of current asthma cases associated with employment during 2020–2021. Methods The 2020–2021 National Health Interview Survey data for persons aged ≥18 years who were employed at any time during the 12 months prior to the interview were analyzed. Results An estimated 12.7 million US working adults had current asthma. Of those, 40% had an asthma attack/episode and 8.6% had an asthma-related ER visit. Prevalence varied by sociodemographic characteristics, industry, and occupation. Highest asthma prevalence was among workers in the administrative, support, waste management, and remediation industry and the community and social services occupation. Nearly half of workers with current asthma in the arts, entertainment, and recreation industry and arts, design, entertainment, sports, and media occupations reported having an asthma attack/episode. Workers in the accommodations and food services industry and food preparation and serving related occupation had the highest asthma-related ER visits. The proportion of current asthma cases attributable to employment was estimated to be 9.2% by industry and 12.2% by occupation. Conclusion An estimated 1.2–1.5 million asthma cases among workers might be attributable to employment by industry and occupation. Disparities in asthma prevalence, asthma attacks/episodes and asthma-related ER visits among workers exist. These findings underscore the importance of early identification of asthma cases in relation to work and implementation of targeted interventions (including, training and education, personal protective equipment use, health surveillance, workplace policies), especially among workers employed in industries and occupations with elevated asthma prevalence.

Structural change and socio-economic disparities in a net zero transition

A net zero transition is likely to generate substantial and irreversible economic transformation. High-carbon industries and their related occupations will disappear, while new low-carbon industries and occupations will be created. In the aggregate, the impact of the transition on GDP and employment is commonly projected to be relatively moderate. However, such estimates hide drastic distributional issues that are sectorally and regionally concentrated. We use three sectorally detailed and regionally disaggregated macroeconomic models to explore the possible levels and impacts of structural change in a well below 2°C scenario. In addition to the expected decline in the carbon-intensive industries, we observe secondary impacts, particularly in the services sectors, that vary significantly between models. The risks entailed with structural change involve worsening economic disparity and societal division that could exacerbate existing socioeconomic and political polarisation. Impact assessments of decarbonisation should consider such distributional issues to avoid post-industrial decline and widening socioeconomic inequalities.

How regions diversify into new jobs: from related industries or related occupations?

ABSTRACT This paper adds a multidimensional perspective to the study of related diversification. We examine how regions diversify into new jobs – defined as unique industry-occupation combinations – asking whether they do so from related industries or related occupations. We use linked employer-employee data for all labour market regions in Norway, covering the time period 2009–2014. Diversification into new jobs is more likely in the presence of related occupations and industries in a region. Furthermore, occupational and industrial relatedness have complementary effects on diversification. Occupational relatedness and its interaction with industrial relatedness are particularly important for diversification into more complex activities.

Occupational security: A holistic values-based framework for supporting occupations and safety

ABSTRACT In an ongoing era of global-scale, cascading, and intersecting crises, including climate change impacts, ongoing armed conflicts, and the COVID-19 pandemic, security is becoming increasingly challenging. The escalating dangers and restrictions arising from these events, adversely affecting life itself and related occupations, has resulted in insecurity disproportionately affecting the most vulnerable and marginalized communities. This often contributes to outcomes that directly relate to security, such as poverty and homelessness. In this conceptual work, we present occupational security as a holistic means to understand and address safety concerns for individuals and populations adversely affected by crises, that have both local and global impacts. Besides global crises, long-term, ongoing, and interrelated security risks from racism, poverty, lack of shelter, and colonisation are also in the purview of occupational security. This concept extends the notion of occupation by including non-humans. Using a values-based framework, occupational security challenges neoliberalism and neoliberal notions of security, which are individualist in nature; and instead, provides a collectivist approach. The values proposed for this framework incorporate sustainability, justice, peace, compassion, authenticity, and accuracy to ensure occupational security and safety for all. We propose that the framework of occupational security has the potential to enhance occupational science scholarship, as well as facilitate collaborative engagement with wider disciplines concerned with issues of security.

Assessment of cerebral drug occupancy in humans using a single PET-scan: A [11C]UCB-J PET study

PurposeHere, we evaluate a PET displacement model with a Single-step and Numerical solution in healthy individuals using the synaptic vesicle glycoprotein (SV2A) PET-tracer [11C]UCB-J and the anti-seizure medication levetiracetam (LEV). We aimed to (1) validate the displacement model by comparing the brain LEV-SV2A occupancy from a single PET scan with the occupancy derived from two PET scans and the Lassen plot and (2) determine the plasma LEV concentration-SV2A occupancy curve in healthy individuals.MethodsEleven healthy individuals (five females, mean age 35.5 [range: 25–47] years) underwent two 120-min [11C]UCB-J PET scans where an LEV dose (5–30 mg/kg) was administered intravenously halfway through the first PET scan to partially displace radioligand binding to SV2A. Five individuals were scanned twice on the same day; the remaining six were scanned once on two separate days, receiving two identical LEV doses. Arterial blood samples were acquired to determine the arterial input function and plasma LEV concentrations. Using the displacement model, the SV2A-LEV target engagement was calculated and compared with the Lassen plot method. The resulting data were fitted with a single-site binding model.ResultsSV2A occupancies and VND estimates derived from the displacement model were not significantly different from the Lassen plot (p = 0.55 and 0.13, respectively). The coefficient of variation was 14.6% vs. 17.3% for the Numerical and the Single-step solution in Bland-Altman comparisons with the Lassen plot. The average half maximal inhibitory concentration (IC50), as estimated from the area under the curve of the plasma LEV concentration, was 12.5 µg/mL (95% CI: 5–25) for the Single-Step solution, 11.8 µg/mL (95% CI: 4–25) for the Numerical solution, and 6.3 µg/mL (95% CI: 0.08-21) for the Lassen plot. Constraining Emax to 100% did not significantly improve model fits.ConclusionPlasma LEV concentration vs. SV2A occupancy can be determined in humans using a single PET scan displacement model. The average concentration of the three computed IC50 values ranges between 6.3 and 12.5 µg/mL. The next step is to use the displacement model to evaluate LEV occupancy and corresponding plasma concentrations in relation to treatment efficacy.Clinical trial registrationNCT05450822. Retrospectively registered 5 July 2022 https://clinicaltrials.gov/ct2/results? term=NCT05450822&Search=Search.

Occupational patterns of opioid-related harms comparing a cohort of formerly injured workers to the general population in Ontario, Canada.

The role of work-related injuries as a risk factor for opioid-related harms has been hypothesized, but little data exist to support this relationship. The objective was to compare the incidence of opioid-related harms among a cohort of formerly injured workers to the general population in Ontario, Canada. Workers' compensation claimants (1983-2019) were linked to emergency department (ED) and hospitalization records (2006-2020). Incident rates of opioid-related poisonings and mental and behavioural disorders were estimated among 1.7 million workers and in the general population. Standardized incidence ratios (SIRs) and 95% confidence intervals (CI) were calculated, adjusting for age, sex, year, and region. Compared to the general population, opioid-related poisonings among this group of formerly injured workers were elevated in both ED (SIR = 2.41, 95% CI = 2.37-2.45) and hospitalization records (SIR = 1.54, 95% CI = 1.50-1.59). Opioid-related mental and behavioural disorders were also elevated compared to the general population (ED visits: SIR = 1.86, 95% CI = 1.83-1.89; hospitalizations: SIR = 1.42, 95% CI = 1.38-1.47). Most occupations and industries had higher risks of harm compared to the general population, particularly construction, materials handling, processing (mineral, metal, chemical), and machining and related occupations. Teaching occupations displayed decreased risks of harm. Findings support the hypothesis that work-related injuries have a role as a preventable risk factor for opioid-related harms. Strategies aimed at primary prevention of occupational injuries and secondary prevention of work disability and long-term opioid use are warranted.

Parental education and occupation in relation to childhood type 1 diabetes: nationwide cohort study

BackgroundSocioeconomic status in the risk of developing type 1 diabetes seems inconsistent. We investigated whether risk of childhood-onset type 1 diabetes differed by parental education or occupation in a nationwide...

Human Health Associated with Occupations Concerning Age and Sex

On par with civilization, perception to their surroundings has been regularly altering the individual lives. Diseases and disorders associated with occupations in relation to age and sex were studied in a selected population of human individuals, dividing them into ‘10’ age groups. Clinical based case control study has been done to determine the occurrence of diseases and disorders in human individuals with different occupations in relation to age and sex. Male individuals with primary type and secondary type of occupations suffered more than that of business level and government and private sector. Female individuals with secondary type, business level and primary type suffered more than that of government and private sector. Age group (in years) 41-70 in male individuals is more affected than 21-40 of primary type and also of secondary type. And in business level and government and private sector, age group 41-60 is more affected than 21-40 with greater significant values indicating p<0.05. Contrary to this in female individuals, age group 31-60 of primary type, 31-50 of secondary type and business level, 21-40 of government and private sector were affected more than age group 21-30, 61-70 of primary type, 21-30 of secondary type and 41-50 of government and private sector with greater significant values indicating p<0.05. Male individuals of age group 41-60 and female individuals of age group 31-60 are more vulnerable to occurrence of several diseases and disorders associated with the various occupations.

Abstract 1955: Novel long-acting covalent PI3Kα inhibitors boost potential action in cancer

Abstract Phosphoinositide 3-kinase (PI3K) is a key regulator of cell proliferation, survival, and metabolism. Hotspot mutations in the PIK3CA gene constitutively activate the catalytic subunit of the PI3Kα isoform and are found in 10-30% of solid tumors. The development of PI3K pathway inhibitors has been hampered by poor drug tolerance and release of negative feedback loops, leading to rapid reactivation of signaling in response to reversible inhibitors. To remedy these challenges, we developed highly selective covalent PI3Kα inhibitors that irreversibly bind to a non-conserved cysteine (C862) located 11 Å outside the ATP-binding site. Here we present the properties of an optimized drug-like covalent lead, dubbed compound 9, and describe the generation of a biotinylated probe developed to be used in conjunction with compound 9 to monitor PI3Kα target occupancy in relation to downstream PI3K signaling outputs. Biochemical investigations of compound 9 using TR-FRET assays showed high affinity binding (Ki), high reaction rates (kinact) for covalent bond formation with PI3Kα, and negligible off-target reactivity. Cellular NanoBRET assays revealed that compound 9 diffuses three times more rapidly into cells as compared to BYL719 (alpelisib), and leads to rapid and potent on-target engagement. Covalent bond formation to residue C862 of PI3Kα was further confirmed by X-ray crystallography. In PIK3CA mutant cancer cell lines, covalent binding of PI3Kα occurred at low nanomolar concentrations and led to persistent inhibition of Akt/PKB phosphorylation for more than 72 hours after drug removal. Notably, investigation of PI3Kα re-synthesis after labeling with compound 9 showed a negligible reappearance in cancer cell lines, which indicates that persistent suppression of PI3Kα signaling by compound 9 results in a much longer half-life for PI3Kα than previously reported. The irreversible inactivation of PI3Kα by compound 9 provides a marked gain in growth inhibition potency (10-600-fold) in PIK3CA mutant cancer cell lines in comparison to clinical reversible PI3Kα inhibitors and allows for intermittent dosing without compromising efficacy. These data collectively demonstrate that compound 9 enables precise and selective targeting of PI3Kα with high potency and long-lasting efficacy in cancer models. The new class of irreversible PI3Kα inhibitors have a unique pharmacology among PI3K inhibitors characterized by strong decoupling of drug exposure from efficacy which may provide opportunities to lower treatment burden in patients. Citation Format: Theodora A. Constantin, Lukas Bissegger, Erhan Keleş, Luka Raguž, Clara Orbegozo, Thorsten Schaefer, Isobel Barlow-Busch, John E. Burke, Chiara Borsari, Matthias P. Wymann. Novel long-acting covalent PI3Kα inhibitors boost potential action in cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1955.

Time since first naturalization is key to explaining non‐native plant invasions on islands

AbstractAimInvestigating the extent of insular invasions by non‐native species (i.e., the number of islands they occupy) is central to island conservation. However, interrelationships among plant life history traits, naturalization histories, and island characteristics in determining island occupancy by non‐native plant species are poorly understood. We investigated whether island occupancy by different non‐native plant species declines in relation to their year of first naturalization and whether periods of first naturalization differ among growth forms, dispersal modes, and biogeographic origins. Then, we asked if non‐native plants that naturalized more recently occur more frequently on islands that are large, less isolated, and close to urban areas. We contrasted trends across growth forms, dispersal modes, and biogeographic origins.Location264 offshore islands in northern Aotearoa New Zealand.TaxaVascular plant species.MethodsWe combined field surveys and published data for 767 non‐native plant species on the islands. We categorized each species according to its growth form (n = 3), dispersal mode (n = 4) and biogeographic origin (n = 5) and identified its year of first naturalization in Aotearoa New Zealand. We tested our hypotheses using ANCOVA and generalized linear models (GLMs).ResultsThere were similar declines in island occupancy in relation to the year of first naturalization in Aotearoa New Zealand across all trait and biogeographic origin categories. First naturalization times of herbaceous species, those with unspecialized dispersal modes, and those originating from Eurasia and the Mediterranean basin were disproportionately earlier than other categories. Non‐native plants with more recent first naturalization occur more frequently on large islands close to urban areas, but not on less isolated ones. Relationships with island characteristics did not differ among trait and biogeographic origin categories.Main ConclusionsOverall, time of first naturalization was more important than trait and biogeographic origin categories in explaining non‐native plant invasion patterns on islands. Since there were similar relationships between island occupancy and the year of first naturalization in Aotearoa New Zealand for all categories, management bodies should focus on non‐native plant species of trait and biogeographic origin categories that have naturalized recently (e.g., woody species from other regions within Oceania), and on large islands close to urban areas. Introduction and naturalization histories provide essential context for interpreting the role of plant traits and biogeographic origin in understanding plant invasions on islands.

Measuring Veterinarian Professions' Readiness for Interprofessional Learning in a Pre- and Post-Intervention Study.

The integration of interprofessional collaboration is becoming increasingly crucial in veterinary care settings, emphasising the need for interprofessional education (IPE) in veterinary programmes. This study explores the readiness for interprofessional learning among German veterinary students, apprentices and related occupations before and after an interprofessional communication course. It assesses the impact of this course on the participants' attitudes using the Readiness for Interprofessional Learning Scale (RIPLS). The course, offered in two iterations, combined asynchronous online modules, live seminars and practical training elements. The RIPLS was administered before and after the course to gauge attitude shifts towards interprofessional learning. Statistical analyses, including McNemar, Cohen's Kappa and exact Fisher tests, were employed to compare pre- and post-test responses. Despite challenges in participant linking, significant findings emerged between the student and apprentice groups in specific areas of the RIPLS, notably in the "Professional Identity" subscale post-course. However, correlations between face-to-face contact and RIPLS ratings were not observed, suggesting a need for more integrated interprofessional learning experiences. While some limitations in sample size and profession distribution hinder generalisability, this study indicates a high receptiveness to interprofessional learning in veterinary education, emphasising the potential for attitude changes with more interactive participation and programme adjustments.

Synthesis, crystal structure and hydrogenation properties of MgxLi3-xB48-y (x = 1.11, y = 0.40).

The ternary magnesium/lithium boride, MgxLi3-xB48-y (x = 1.11, y = 0.40, idealized formula MgLi2B48), crystallizes as its own structure type in P43212, which is closely related to the structural family comprising α-AlB12, Be0.7Al1.1B22 and tetra-gonal β-boron. The asymmetric unit of title structure contains two statistical mixtures Mg/Li in Wyckoff sites 8b with relative occupancies Mg:Li = 0.495 (9):0.505 (9) and 4a with Mg:Li = 0.097 (8):0.903 (8). The boron atoms occupy 23 8b sites and two 4a sites. One of the latter sites has a partial occupancy factor of 0.61 (2). Both unique Mg/Li atoms adopt a twelvefold coordination environment in the form of truncated tetra-hedra (Laves polyhedra). These polyhedra are connected by triangular faces to four [B12] icosa-hedra. The boron atoms exhibit four kinds of polyhedra, namely penta-gonal pyramid (coordination number CN = 6), distorted tetra-gonal pyramid (CN = 5), bicapped hexa-gon (CN = 8) and gyrobifastigium (CN = 8). At the gas hydrogenation of MgLi2B48 alloy, formation of the eutectic composite hydride LiBH4+Mg(BH4)2 and amorphous boron is observed. In the temperature range 543-623 K, the hydride eutectics decompose, forming MgH2, LiH, MgB4, B and H2.