Leaf wax composition and distribution of Tillandsia landbeckii reflects moisture gradient across the hyperarid Atacama Desert

In the hyperarid Atacama Desert, water availability plays a crucial role in allowing plant survival. Along with scant rainfall, marine advective fog frequently occurs along the coastal escarpment fueling isolated mono-specific patches of Tillandsia vegetation. In this study, we investigate the lipid biomarker composition of the bromeliad Tillandsia landbeckii (CAM plant) to assess structural adaptations at the molecular level as a response to extremely arid conditions. We analyzed long-chain n-alkanes and fatty acids in living specimens (n = 59) collected from the main Tillandsia dune ecosystems across a 350 km coastal transect. We found that the leaf wax composition was dominated by n-alkanes with concentrations (total average 160.8 ± 91.4 µg/g) up to three times higher than fatty acids (66.7 ± 40.7 µg/g), likely as an adaptation to the hyperarid environment. Significant differences were found in leaf wax distribution (Average Chain Length [ACL] and Carbon Preference Index [CPI]) in the northern zone relative to the central and southern zones. We found strong negative correlations between fatty acid CPI and n-alkane ACL with precipitation and surface evaporation pointing at fine-scale adaptations to low moisture availability along the coastal transect. Moreover, our data indicate that the predominance of n-alkanes is reflecting the function of the wax in preventing water loss from the leaves. The hyperarid conditions and good preservation potential of both n-alkanes and fatty acids make them ideal tracers to study late Holocene climate change in the Atacama Desert.

Bilingual experiences induce dynamic structural changes to basal ganglia and the thalamus

Bilingualism has been linked to structural adaptations of subcortical brain regions that are important nodes in controlling of multiple languages. However, research on the location and extent of these adaptations has yielded variable patterns. Existing literature on bilingualism-induced brain adaptations has so far largely overseen evidence from other domains that experience-based structural neuroplasticity often triggers non-linear adaptations which follow expansion-renormalisation trajectories. Here we use generalised additive mixed models (GAMMs) to investigate the non-linear effects of quantified bilingual experiences on the basal ganglia and thalamus in a sample of bilinguals with wide range of bilingual experiences. Our results revealed that volumes of bilateral caudate nuclei and accumbens were positively related to bilingual experiences in a non-linear pattern, with increases followed by decreases, in the most experienced bilinguals, suggesting a return to baseline volume at higher levels of bilingual experience. Moreover, volumes of putamen and thalamus were positively linearly predicted by bilingual experiences. The results offer the first direct evidence that bilingualism, similarly to other cognitively demanding skills, leads to dynamic subcortical structural adaptations which can be nonlinear, in line with expansion-renormalisation models of experience-dependent neuroplasticity.

Patellar Tendon Structural Adaptations Occur during Pre-Season and First Competitive Cycle in Male Professional Handball Players

Background: While there is evidence that tendon adapts to training load, structural alterations in the patellar tendon in response to training loads are still unclear. The aim of this study is to identify changes in patellar tendon structure throughout pre-season and after finalizing the first competitive cycle. Methods: Nineteen professional handball players participated in the aforesaid cross-sectional study, in which patellar tendon scan and counter movement jump (CMJ) performance were conducted. Measurements were taken on the first and last day of pre-season training, and at the end of the first competitive cycle. Results: The results revealed that variation on the tendon structure occurred, mainly at the end of pre-season training; for injured tendons this occurred at the proximal (Right p = 0.02), distal (Right p = 0.01), and (Left p = 0.02) tendon, while changes in healthy tendons occurred at the mid (Left p = 0.01) and distal tendon (Right p = 0.01). At the end of the first competitive cycle, changes were observed in the distal injured tendon (p = 0.02). Conclusion: Patellar tendon shows greater structural change after completing pre-season training than at the end of the first competitive cycle, from which it may be inferred that gradual loading during pre-season training allows the tendon to adapt and potentially decrease the onset of patellar tendinopathy.

The morphometric of lycopsid sporophylls and the evaluation of their dispersal potential: an example from the Upper Devonian of Zhejiang Province, China

Background Previous studies have discussed the special structural adaptations of Late Palaeozoic lycopsids, for example, the dispersal potential of reproductive organs. Based on materials from the Upper Devonian Wutong Formation in Changxing County, Zhejiang Province, China, we now analyze the morphometric and perform some calculation to evaluate the dispersal of sporophyll units of lycopsids. Results The fossil sporophyll units are divided into two types in view of obvious difference in shape and we name two new (form) species for them. We also analyze the falling process and give the calculation method of dispersal distance. Conclusions The fossil sporophyll units show relatively poor potential of wind dispersal compared with modern samaras, and show potential adaptation to the turbulent environment.

Morpho-Anatomy of the Gynoecium and Fruit in Three Ornamental Members of Campanuloideae (Campanulaceae)

Gynoecium and fruit micromorphology and anatomy were studied using light microscopy in three species of Campanuloideae belonging to the tribes Cyanantheae ( Platycodon grandiflorus ), Wahlenbergieae ( Jasione montana ), and Campanuleae ( Adenophora liliifolia ) of the native and cultivated flora of Ukraine, to elucidate structural adaptations for fruit dehiscence. The studied species differed in flower/fruit orientation, carpel number, ovary insertion, and capsule-opening position, and the information provided a background for the discovery of common anatomical features influencing fruit dehiscence. In the studied species, the synascidiate and symplicate zones in the ovary and prominent placentae were found to be located near the mid-region of the ovary. The distinct innervation of the ovary wall and ovules was described. In P. grandiflorus , the septa and fruit wall contained a lignified parenchyma in a subepidermal position, while in J. montana and A. liliifolia , lignification was observed only in proximal portions of the septa, above the placenta ( J. montana ), or was noted as a narrow strand from the ovary base to the mid-region, called “axicorn” ( A. liliifolia ). In all the studied species, unlignified endocarpium was detected. The semi-inferior capsule of P. grandiflorus has been defined as a capsule of the Forsythia -type, with a sclerenchymatous layer in the inner zone of the mesocarpium. In J. montana and A. liliifolia , a new histogenetic type of capsule is described as Campanula -type, without lignified layers in the fruit wall and with lignified tissue in the septa, which enabled dehiscence. Our study proposed for the first time the classification of the capsules found in the studied species based on the development of openings in the superior or inferior regions of the fruits. The upright fruits of P. grandiflorus and J. montana reveal incomplete dorsiventral dehiscence in the superior region of the fruit, while dehiscence of pendent fruits of A. liliifolia is hippocrepiform-septifragal interlocular and occurs in the inferior region of the fruit at its base, as revealed previously in Campanula latifolia fruit.

Socio-Economic Implications and Potential Structural Adaptations of the Tunisian Agricultural Sector to Climate Change

Climate change is expected to have serious economic and social impacts on Tunisian rural farmers. The extent of these impacts will largely depend on the level of political and structural adaptations. This study aims to evaluate the effect of increasing water shortages on agricultural income and employment. It also analyzes structural adaptation strategies implemented by farmers in response to this challenge. We have therefore developed a regionally disaggregated supply model to simulate three types of scenarios concerning (i) decreasing quantities of irrigation water at the regional level; (ii) enhanced irrigation water use efficiency; and (iii) higher production prices. Observed crop production data for 21 crops and 24 districts of Tunisia have been used. Districts have been aggregated into five regions based on bioclimatic homogeneity. Results show that climate change will lead to the reduction of irrigated areas and an increased importance of rainfed agriculture. It will also have a negative impact on farm income and employment. This negative effect can be fully mitigated by improving water use efficiency, at farm and perimeter levels, and can be reversed by offering more attractive producer prices to farmers through enhanced value chain integration.

Characterizing the Brain Structural Adaptations Across the Motherhood Transition

Women that become mothers face notable physiological adaptations during this life-period. Neuroimaging studies of the last decade have provided grounded evidence that women's brains structurally change across the transition into motherhood. The characterization of this brain remodeling is currently in its early years of research. The current article reviews this scientific field by focusing on our longitudinal (pre-to-post pregnancy) Magnetic Resonance Imaging (MRI) studies in first-time parents and other longitudinal and cross-sectional studies of parents. We present the questions that are currently being answered by the parental brain literature and point out those that have not yet been explored. We also highlight potential confounding variables that need to be considered when analyzing and interpreting brain changes observed during motherhood.

Extremophilic Oxidoreductases for the Industry: Five Successful Examples With Promising Projections

In a global context where the development of more environmentally conscious technologies is an urgent need, the demand for enzymes for industrial processes is on the rise. Compared to conventional chemical catalysts, the implementation of biocatalysis presents important benefits including higher selectivity, increased sustainability, reduction in operating costs and low toxicity, which translate into cleaner production processes, lower environmental impact as well as increasing the safety of the operating staff. Most of the currently available commercial enzymes are of mesophilic origin, displaying optimal activity in narrow ranges of conditions, which limits their actual application under industrial settings. For this reason, enzymes from extremophilic microorganisms stand out for their specific characteristics, showing higher stability, activity and robustness than their mesophilic counterparts. Their unique structural adaptations allow them to resist denaturation at high temperatures and salinity, remain active at low temperatures, function at extremely acidic or alkaline pHs and high pressure, and participate in reactions in organic solvents and unconventional media. Because of the increased interest to replace chemical catalysts, the global enzymes market is continuously growing, with hydrolases being the most prominent type of enzymes, holding approximately two-third share, followed by oxidoreductases. The latter enzymes catalyze electron transfer reactions and are one of the most abundant classes of enzymes within cells. They hold a significant industrial potential, especially those from extremophiles, as their applications are multifold. In this article we aim to review the properties and potential applications of five different types of extremophilic oxidoreductases: laccases, hydrogenases, glutamate dehydrogenases (GDHs), catalases and superoxide dismutases (SODs). This selection is based on the extensive experience of our research group working with these particular enzymes, from the discovery up to the development of commercial products available for the research market.