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Effect of temperature on the interaction rules between grain size and reaction rate of Al-Ga-based alloys for hydrogen generation
No full textControllable hydrogen generation rate of Al-Ga-based on-site hydrogen supply materials significantly impacts their practical application. In many scenarios, the hydrolysis reaction occurs at elevated temperatures, which is a factor often overlooked in its effect on reaction kinetics. This study investigates the relationship between grain size and reaction rate in Al-Ga-based alloys for hydrogen generation, specifically examining temperature influences. We synthesized a series of Al-Ga-based alloys with antimony (Sb) as a refining agent, systematically varying the Sb content to modulate grain size. The hydrogen production rates were measured across various temperatures. Our results indicate that Sb effectively refines Al alloys, significantly affecting the Al-H2O reaction rate by altering selective growth orientation and grain size. The most pronounced refinement is at 0.1 wt% Sb, yielding the smallest grain size and highest hydrogen production rate, making it suitable for substantial hydrogen generation applications. Further investigations reveal a non-linear relationship between Sb's effect on grain size and the reaction rate. At elevated temperatures, the fragmentation of the Al alloy intensifies, amplifying the impact of grain size on the hydrogen generation rate. In contrast, this regulatory mechanism is diminished at lower temperatures. We also validated this relationship with previously reported Al-Ga-based hydrogen-producing alloys. These findings offer valuable insights, suggesting that strategic grain size modifications can effectively enhance hydrogen generation rates at elevated temperatures
A story of strategic Turkish motherhoods within a patriarchal structure : The Case of 2 Girls (2005)
No full textThe Prediction of Diagnostic Change From Bipolar Disorder to Schizophrenia and Schizophrenia to Bipolar Disorder in a Population-Based, Longitudinal, National Swedish Sample
No full textBackground and Hypothesis: To clarify, in a large, representative, longitudinal sample, the rate and predictors of diagnostic conversion from Bipolar Disorder (BD) to Schizophrenia (SZ) and from SZ→BD. Design: From individuals born in Sweden 1950–1995 and living there in 1970 or later, we identified at least one initial diagnoses of SZ (n = 8449) and BD (n = 8438) followed for a minimum of 10 and a mean of 24 years. Diagnostic conversion required, respectively, at least two final diagnoses of BD and SZ 30 days apart with no intervening diagnosis of SZ or BD. Results: At follow-up, rates of BD→SZ and SZ→BD conversion were 10.1 and 4.5%, respectively. Conversions occurred slowly, with around 50% completed in the first decade. Using a diverse range of variables available at first onset including family genetic risk scores, BD→SZ conversion was predicted with greater accuracy (AUC = 0.78) than SZ→BD conversion (AUC = 0.65). The strongest predictors of BD→SZ conversion were earlier years of birth, younger age at BD onset, low BD genetic risk, and being unmarried at BD onset. SZ→BD conversion was most strongly predicted by high BD genetic risk, being married at SZ onset, female sex, early age at SZ onset, and an MD episode prior to SZ onset. Cases of BD and SZ in the highest decile for conversion risk had HRs for a diagnostic change of, respectively, 12.5 and 3.4. Conclusions: Diagnostic conversion of BD→SZ and SZ→BD are not rare, are moderately predictable, and should likely be accounted for in many research designs
Hydrogen migration reactions via low internal energy pathways in aminobenzoic acid dications
No full textHydrogen migration is a ubiquitous phenomenon upon dissociation of organic molecules. Here we investigate the formation of a H3O+ fragment after core-level photoionization and Auger decay in aminobenzoic acid molecules - a process that requires the migration of at least two hydrogen atoms. Using photoelectron-photoion coincidence spectroscopy, the formation of a H3O+ fragment is observed to be more probable in ortho-aminobenzoic acid than in meta- and para-aminobenzoic acid. Energy-resolved Auger electron-photoion coincidences are measured for the ortho-isomer to investigate the internal energy dependence of the fragmentation channels, most notably of those producing H3O+. The corresponding fragmentation channels and their mechanisms are investigated by exploring the potential energy surface with ab initio quantum chemistry methods and molecular dynamics simulations. Excited-state modeling of dicationic ortho-aminobenzoic acid is used to interpret features in the Auger spectra and identify the electronic states contributing to the signals in the Auger electron photoion coincidence map. We show that populating low-energy excited states of the dication is sufficient to trigger hydrogen migration and produce H3O+ efficiently
Synthetic human embryos, artificial wombs, in vitro gametogenesis, and other (reproduction) technologies : Do we have the laws and regulations we need for these brand new ways to make babies?
No full textAssociation between plasma interferon-γ levels and preeclampsia in pregnant women screened for tuberculosis infection
No full textObjectives: Pregnancy can influence immune control of Mycobacterium tuberculosis infection (MtbI). We recently reported an association between MtbI and pregnancy complications, particularly severe preeclampsia, in a registry-based cohort of women originating in tuberculosis-endemic countries screened for MtbI in Swedish antenatal care, implying a potential role of MtbI for the development of preeclampsia. Here, we aimed to investigate the role of plasma interferon-γ secretion as a potential mediator of this interaction. Methods: Plasma interferon-γ levels were compared with women with MtbI (defined as positive QuantiFERON results in the absence of tuberculosis) and MtbI-negative women regarding any diagnosis of preeclampsia and severe preeclampsia. Odds of preeclampsia and severe preeclampsia were compared with respect to MtbI status and interferon-γ levels >90th percentile in the study population (0.28 IU/mL). Results: MtbI was detected in 700 of 3605 women (19.4%) and preeclampsia was diagnosed in 110 (3.1%), among whom 50 (1.4%) had severe preeclampsia. Women with MtbI had higher interferon-γ levels than MtbI-negative women (median 0.12 IU/mL, interquartile range [IQR], 0.06–0.26 IU/mL; vs. 0.07 IU/mL, IQR 0.04–0.12 IU/mL; p 0.28 IU/mL, than in MtbI-negative women with interferon-γ levels 0.28 IU/mL, had increased odds of preeclampsia or severe preeclampsia compared to MtbI-negative women with interferon-γ levels <0.28 IU/mL. Discussion: These findings suggest that interferon-γ secretion could be involved as a mediator in the association between MtbI and development of preeclampsia
Low cross-taxon congruence and weak stand-age effects on biodiversity in Swedish oak forests
No full textAssessing cross-taxon congruence is vital for effective forest conservation, because different taxonomic groups may respond inconsistently to key habitat variables such as stand age. We examined six taxonomic groups—insects, arachnids, springtails, epiphytic lichens, bryophytes, and vascular plants—across 25 Swedish oak stands ranging from 19 to 165 years old to determine whether species richness correlated among groups (cross-taxon congruence) and how it related to stand age. In total, we identified 22,276 unique taxa (with on average 4,128 per stand) using COI metabarcoding for arthropods and field surveys for lichens, bryophytes, vascular plants. Associations of species richness in each taxonomic group with richness in the others were weak, indicating low cross-taxon congruence. Only lichens showed a significant, positive relationship of species richness with stand age, while springtails exhibited a unimodal pattern, and the other four groups were unaffected by stand age. Although species composition in four groups changed with stand age, the explanatory power was generally low. Overall, the heterogeneous responses of different groups indicated by our findings caution against the use of single taxonomic groups or environmental variables as indicators and keys to successful protection of biodiversity. Instead, forest management strategies should adopt multi-taxon assessments and recognize the value of both younger and older stands to safeguard biodiversity in oak-dominated landscapes
Induced allopatry as main mechanism explaining trap catch reduction in low dose mating disruption trials on the strawberry pest Acleris comariana (Lepidoptera: Tortricidae)
No full textBACKGROUND: The strawberry tortrix, Acleris comariana (Lepidoptera: Tortricidae), is a destructive pest of strawberry in Denmark and southern Sweden. The efficacy of pheromone-based communication disruption of the species was examined in crop fields in southern Sweden. Due to the high cost of purchasing or synthesizing the pheromone (E)-11,13-tetradecadienal, lower quantities were applied per ha compared to similar mating disruption studies on other tortricid pests. RESULTS: When treating 1 ha within fields with 14 or 1.4 g of pheromone and using rubber septa as dispensers, trap catches were reduced by ≥98% versus control areas. When treating whole fields with 0.45–0.90 g/ha and using 1 g SPLAT droplets as dispensers, the effect on trap catch was less pronounced (63–95% reduction vs control fields). A corresponding reduction in larval numbers following the treatment was not achieved. Additional experiments revealed that males are more attracted to SPLAT droplets compared to trap lures, and aggregate near SPLAT droplets, indicating that low catches in traps were due to induced allopatry, a form of competitive disruption. In addition, female-baited traps were outcompeted when placed close to septum-baited traps. Pest densities were high, and the lack of control effect could be attributed to high encounter rates between the sexes despite the female competitive disadvantage, making mating disruption less efficient. CONCLUSION: Our data show the potential for pheromone-based control of A. comariana as part of integrated pest management, but the method needs optimization regarding density and strength of dispensers and ways to reduce the initial density of the pest to levels where competitive mechanisms of mating disruption can be efficient
Reconstructing Reservoir Water Level-Area-Storage Volume Curve Using Multi-source Satellite Imagery and Intelligent Classification Algorithms
No full textThe water level-area-storage volume (Z-A-V) relationship serves as the cornerstone of reservoir operations, governing water allocation, flood mitigation, and power generation. Sedimentation-induced capacity alterations can progressively degrade Z-A-V accuracy, yet systematic curve updates remain inadequately implemented across developing nations. Traditional reconstruction approaches face inherent limitations due to resource-intensive requirements including costly field surveys and data scarcity. Emerging satellite remote sensing technologies show transformative potential for dynamic reservoir monitoring, though their application in Z-A-V curve updating still requires substantive exploration. This study evaluates the capability of multi-source satellite imagery, including optical data from Landsat 8 and Sentinel-2, and synthetic aperture radar (SAR) data from Sentinel-1, for accurately reconstructing the Z-A-V curve. To extract high-accuracy reservoir surface extents, two advanced algorithms–Random Forest Classification (RFC) and Otsu thresholding–are applied to the optimal and SAR imagery, respectively, to delineate water and non-water pixels. The suitability of the satellite-derived Z-A-V curve is further assessed by estimating the storage capacity loss due to sedimentation accumulation and comparing these estimates with that derived from design curve. Using the Hongjiadu Reservoir in the upper reach of the Wujiang River, China, as a case study, the results show that: (1) all three satellite datasets accurately extract the reservoir surface areas, achieving average accuracies of 96%, 89%, and 88% for Sentinel-1, Landsat 8, and Sentinel-2, respectively; (2) the Z-A curve reconstructed from Sentinel-1 SAR imagery achieves the highest accuracy with and the coefficient of determination (R²) > 0.99 and root mean square error (RMSE) < 1; (3) the storage capacity loss estimated from Sentinel-1-derived Z-V curve (0.065 billion m³) closely aligns with the sedimentation-based estimate (0.077 billion m³), outperforming other imagery sources. This study demonstrates the significant potential of integrating high-quality satellite imagery and intelligent algorithms to enable frequent, cost-effective, and large-scale updates to reservoir Z-A-V curves, bridging a crucial gap in adaptability evaluation of multi-source remote sensing-based Z-A-V characteristic reconstructions
Prevention of type 2 diabetes in migrant populations from low- and middle-income countries living in high-income countries
No full textThe rising prevalence of type 2 diabetes among migrant populations from low- and middle-income countries (LMICs) living in high-income countries (HICs) presents a significant public health challenge. Migrants often experience lifestyle changes, socioeconomic disadvantages and barriers to accessing healthcare, which can increase their risk for type 2 diabetes. This review explores the prevention and management of type 2 diabetes in these migrant populations, emphasising the need for culturally sensitive strategies. Key interventions for mitigating the burden of type 2 diabetes include tailored dietary and physical activity programmes, community-based initiatives and healthcare models that consider social determinants of health and integrate traditional beliefs with evidence-based practices across genders. Addressing language barriers, improving health literacy and engaging trusted community leaders are all critical for effective intervention uptake. Additionally, policy measures to reduce structural inequalities, such as improving healthcare access and food security, are essential. Future research should focus on evaluating the long-term effectiveness of culturally sensitive interventions across gender and different migrant populations and on scaling successful models for broader implementation