Later Stages Of Development Research Articles

Effects of climate and forest development on habitat specialization and biodiversity in Central European mountain forests.

Mountain forests are biodiversity hotspots with competing hypotheses proposed to explain elevational trends in habitat specialization and species richness. The altitudinal-niche-breadth hypothesis suggests decreasing specialization with elevation, which could lead to decreasing species richness and weaker differences in species richness and beta diversity among habitat types with increasing elevation. Testing these predictions for bacteria, fungi, plants, arthropods, and vertebrates, we found decreasing habitat specialization (represented by forest developmental stages) with elevation in mountain forests of the Northern Alps - supporting the altitudinal-niche-breadth hypothesis. Species richness decreased with elevation only for arthropods, whereas changes in beta diversity varied among taxa. Along the forest developmental gradient, species richness mainly followed a U-shaped pattern which remained stable along elevation. This highlights the importance of early and late developmental stages for biodiversity and indicates that climate change may alter community composition not only through distributional shifts along elevation but also across forest developmental stages.

Effect of organic farming on root microbiota, seed production and pathogen resistance in winter wheat fields

Societal Impact StatementAgricultural intensification is a major driver of biodiversity decline in agrosystems. For instance, it has been shown that conventional farming leads to a decline in soil microbial diversity and triggers a strong selection process, altering the functioning of the whole ecosystem. The present study shows that organic farming increases diversity and affects composition of crop plant microbiota, mostly as a response to field management and soil characteristics. Furthermore, crop plant microbiota influences crop production and resistance to pathogens. Therefore, agricultural practices affect plant performance through microorganism‐mediated changes, which may be important pillars of future sustainable crop production.Summary Agricultural intensification threatens biodiversity, but the effects of intensification on microorganisms are still overlooked despite their role in ecosystem functioning. Microorganisms associated with plants provide many services that affect plant growth and health. Organic farming is expected to strongly affect species composition, richness, and their interactions. We analyzed the effect of the farming system on endophytic microbial assemblages associated with winter wheat plants and plant performance in the field. We collected environmental data through farmer interviews, soil analyses, and plant inventories and analyzed root microbiota at vegetative and flowering stages. Organic farming increased fungal and bacterial diversity associated to wheat plants and affected species composition in most phyla. This effect was mostly due to soil characteristics and field management and a little to plant diversity in the field. Microbial responses were more pronounced at the late developmental stage, likely as a result of accumulative effect of management actions during plant development. Seed production and resistance to pathogens were related to specific phyla that are important for seed production and/or wheat resistance to septoriose. This work advances our understanding of how agricultural practices affect plant performance through microorganism‐mediated changes and supports the use of microorganisms as pillars of sustainable crop production.

Absorption and translocation to fruit for cesium applied on apple tree leaf surface.

We investigated the behavior of stable Cs+ ions contained in droplets applied directly on the leaf surfaces of plumleaf crab apple trees (2-3years old Malus domestica 'Alps Otome') at three different fruit growing stages: before bearing fruit, early fruit development and late fruit development stages. Most of the Cs was rapidly transferred from the leaf surfaces into the applied leaves after application, and then gradually transferred to the fruit through the branches. The mean proportion of Cs transferred to fruit by harvest time ranged from 11 to 30% not directly depending on the fruit growing stages. Cs absorption from leaf surfaces was faster at early and late fruit development stages than before bearing fruit stage, and Cs transfer from leaf surfaces to the fruit was faster as the fruit growing stage progressed. To describe the transfer of Cs, we constructed a compartment model using the datasets of obtained for each fruit growing stage. However, it did not well reproduce the measured values, showing that further studies are necessary.

The E3 ubiquitin ligase RNF220 maintains hindbrain Hox expression patterns through regulation of WDR5 stability.

The spatial and temporal linear expression of Hox genes establishes a regional Hox code, which is crucial for the antero-posterior (A-P) patterning, segmentation, and neuronal circuit development of the hindbrain. RNF220, an E3 ubiquitin ligase, is widely involved in neural development via targeting of multiple substrates. Here, we found that the expression of Hox genes in the pons was markedly up-regulated at the late developmental stage (post-embryonic day E15.5) in Rnf220-/- and Rnf220+/- mouse embryos. Single-nucleus RNA sequencing (RNA-seq) analysis revealed different Hox de-repression profiles in different groups of neurons, including the pontine nuclei (PN). The Hox pattern was disrupted and the neural circuits were affected in the PN of Rnf220+/- mice. We showed that this phenomenon was mediated by WDR5, a key component of the TrxG complex, which can be polyubiquitinated and degraded by RNF220. Intrauterine injection of WDR5 inhibitor (WDR5-IN-4) and genetic ablation of Wdr5 in Rnf220+/- mice largely recovered the de-repressed Hox expression pattern in the hindbrain. In P19 embryonal carcinoma cells, the retinoic acid-induced Hox expression was further stimulated by Rnf220 knockdown, which can also be rescued by Wdr5 knockdown. In short, our data suggest a new role of RNF220/WDR5 in Hox pattern maintenance and pons development in mice.

The E3 ubiquitin ligase RNF220 maintains hindbrain Hox expression patterns through regulation of WDR5 stability

The spatial and temporal linear expression of Hox genes establishes a regional Hox code, which is crucial for the antero-posterior (A-P) patterning, segmentation, and neuronal circuit development of the hindbrain. RNF220, an E3 ubiquitin ligase, is widely involved in neural development via targeting of multiple substrates. Here, we found that the expression of Hox genes in the pons was markedly up-regulated at the late developmental stage (post-embryonic day E15.5) in Rnf220-/- and Rnf220+/- mouse embryos. Single-nucleus RNA sequencing (RNA-seq) analysis revealed different Hox de-repression profiles in different groups of neurons, including the pontine nuclei (PN). The Hox pattern was disrupted and the neural circuits were affected in the PN of Rnf220+/- mice. We showed that this phenomenon was mediated by WDR5, a key component of the TrxG complex, which can be polyubiquitinated and degraded by RNF220. Intrauterine injection of WDR5 inhibitor (WDR5-IN-4) and genetic ablation of Wdr5 in Rnf220+/- mice largely recovered the de-repressed Hox expression pattern in the hindbrain. In P19 embryonal carcinoma cells, the retinoic acid-induced Hox expression was further stimulated by Rnf220 knockdown, which can also be rescued by Wdr5 knockdown. In short, our data suggest a new role of RNF220/WDR5 in Hox pattern maintenance and pons development in mice.

The first record of larval <i>Crassostrea gigas</i> (Thunberg 1793) (Bivalvia, Ostreidae) from the Black Sea

Larvae of the oyster, Crassostrea gigas (Thunberg 1793) are being found in the plankton of the Black Sea for the first time. The studies were carried out in 2014–2023 along the Sevastopol coast. Samples were taken monthly with a Jeddy plankton net (inlet diameter 36 cm, mill gas mesh 135 µm). A water layer of 10–0 m was investigated. Live material was processed by total counting the larvae in the Bogorov chamber, using MBS-9 and Mikmed-5 light microscopes. Oyster larvae were recorded in August 2020 and observed in the plankton from the end of August to the beginning of October. They were also found in the waters at Miskhor, southern coast of Crimea in August 2023. The density of larvae amounted to 1–3 ind./m3. Larvae were found at the following water temperatures: minimum, 19.7 °C (September 2021), maximum, 26.6 °C (August 2022). In August, the larvae of C. gigas were at the stage of veliconch, their sizes ranging 275–340 mkm. The sizes of oyster larvae in September and October were 380 mkm, being already in the late stages of development. In the coastal waters of the northern part of the Black Sea, C. gigas larvae can settle on substrates from late August to mid-October.

Empowering model repair: a rule-based approach to graph repair without side effects—extended version

AbstractWorking with models can lead to inconsistencies, e.g., due to erroneous or contradictory actions during concurrent modeling processes. Modern modeling environments typically tolerate inconsistencies and support their detection. However, at a later stage of development, models are expected to be consistent, meaning their inconsistencies should be considered and resolved. The process of resolving model inconsistencies is commonly referred to as model repair. Our approach to model repair is semi-automatic in the sense that the repair tool computes appropriate repair plans and the modeler decides which path to take. The speciality of our approach is that the repair process can register any small improvement in the model. This allows the interaction with the user to be optimized, resulting in an approach with a high level of automation on the one hand and flexible configuration options on the other. The approach focuses on providing repair plans that do not have side effects, i.e., the computed repair plans do not inadvertently introduce a new inconsistency of already repaired constraints into the model. Since models often have a graph-like structure, we present our approach to model repair based on graphs. Our approach is completely formal—we use the algebraic graph transformation approach to prove its correctness. We also present a prototype implementation of our repair approach based on the Eclipse Modeling Framework and Henshin, a model transformation engine based on graph transformation, to perform the actual model repair. A first performance evaluation shows that graphs with up to 1000 nodes can be repaired in about 10 s.

Pressure-temperature-time paths from metapelites reveal neoproterozoic continental crust underthrusting related to the West Gondwana amalgamation

In this contribution, we employed a petrochronological approach to investigate the tectonometamorphic evolution of Al-rich garnet-staurolite and garnet-staurolite-kyanite (biotite- and plagioclase-free) metapelites of the southernmost portion of the Neoproterozoic Brasília orogen. We have reconstructed the first prograde to peak pressure-temperature-time (P-T-t) paths reported for metamorphic units of the area, by combining petrographic analyses, quantitative compositional mapping of major elements, phase equilibrium modeling, and EPMA Th–U–Pb monazite chemical dating. The metamorphic reactions involved in the prograde metamorphic evolution are discussed, including the effects of garnet fractionation, exhaustion of reactants, and re-equilibration reactions on the major-element composition of garnet porphyroblasts, and their influence on P-T condition estimates. Raman spectroscopy on carbonaceous material (RSCM) thermometry provided insights into the synkinematic retrograde path. A steep prograde path marked by two stages is recorded by the garnet porphyroblasts of garnet-staurolite-muscovite (±kyanite) schists: (i) 555–585 °C and 0.60–0.90 GPa; (ii) 590–635 °C and 1.0–1.4 GPa. Monazite crystals record the prograde to peak path from ca. 630–625 Ma to ca. 605–595 Ma. Matrix graphite crystals suggest post-peak cooling to 400–500 °C concurrent with the late stages of development of the main foliation. The reconstructed P-T-t paths indicate an intermediate dT/dP metamorphism, and a burial rate of ~0.55 km/Ma, with garnet compositional zoning suggesting that the high-pressure P-T-t path resulted from a single metamorphic event. The corresponding geothermal gradients, and in-situ ages, combined with regional evidence, suggest that peak metamorphic conditions were attained during collisional underthrusting of the continental crust related to the West Gondwana amalgamation.

Evolvability in Artificial Development of Large, Complex Structures and the Principle of Terminal Addition.

Epigenetic tracking (ET) is a model of development that is capable of generating diverse, arbitrary, complex three-dimensional cellular structures starting from a single cell. The generated structures have a level of complexity (in terms of the number of cells) comparable to multicellular biological organisms. In this article, we investigate the evolvability of the development of a complex structure inspired by the "French flag" problem: an "Italian Anubis" (a three-dimensional, doglike figure patterned in three colors). Genes during development are triggered in ET at specific developmental stages, and the fitness of individuals during simulated evolution is calculated after a certain stage. When this evaluation stage was allowed to evolve, genes that were triggered at later stages of development tended to be incorporated into the genome later during evolutionary runs. This suggests the emergence of the property of terminal addition in this system. When the principle of terminal addition was explicitly incorporated into ET, and was the sole mechanism for introducing morphological innovation, evolvability improved markedly, leading to the development of structures much more closely approximating the target at a much lower computational cost.

Floral Developmental Morphology and Biochemical Characteristics of Male Sterile Mutants of Lagerstroemia indica.

Male sterility is a common phenomenon in higher plants and often plays an important role in the selection of superior offspring. 'Xiang Yun' is a mutant of Lagerstroemia indica that does not bear fruit after flowering, and its flowering period is significantly longer than that of normal L. indica. To explore the timing and molecular mechanisms of sterility in 'Xiang Yun', this study determined the period of sterility through anatomical observation and compared the content of nutrients and the activity of antioxidative enzymes at different stages of flower development. Finally, sequence alignment and qPCR were used to analyze the differences in pollen development genes between 'Xiang Yun' and 'Hong Ye'. The results showed that the anthers of 'Xiang Yun' dispersed pollen normally, but the pollen grains could not germinate normally. Observations with scanning electron microscopy revealed that the pollen grains were uneven in size and shriveled in shape. Further observation of anther sections found that abnormal development of the microspores began at the S2 stage, with the callose wall between microspores of 'Xiang Yun' being thicker than that of 'Hong Ye'. In addition, during the flower development of 'Xiang Yun', the contents of soluble sugar, soluble protein, free proline, and triglycerides were deficient to varying degrees, and the activities of POD, SOD, and MDA were lower. Sequence alignment and qPCR showed that there were several mutations in EFD1, TPD1, and DEX1 of 'Xiang Yun' compared with 'Hong Ye', and the expression levels of these genes were abnormally elevated in the later stages of development. Our results clarified the timing and phenotype of male sterility in 'Xiang Yun'. This provides solid and valuable information for further research on the molecular mechanism of sterility in 'Xiang Yun' and the genetic breeding of crape myrtle.

Clinopyroxenite-Wehrlite Porya Guba Complex with Fe-Ti-V and PGE-Cu-Ni Mineralization in the Northeastern Part of the Fennoscandian Shield: Evidence of Post-Orogenic Formation from Sm-Nd Isotope System

The Porya Guba clinopyroxenite–wehrlite complex is located in the core of the Lapland–Kola collisional orogen (~2.0–1.9 billion years old) in the northeastern part of the Fennoscandian Shield and contains iron–titanium–vanadium and nickel–copper mineralization with platinum group elements (PGEs). The controversial geological position of the complex within the mafic granulites of the Kolvitsa mélange (pre-, syn- or post-orogenic) is clarified by Sm-Nd isotopic dating of the rocks and mineralization. The Sm-Nd age of the barren clinopyroxenites that dominate the complex is 1858 ± 34 Ma (εNd(T) = −1.5) and is interpreted as the time of its emplacement as evidenced by a sample from the largest intrusion, named Zhelezny. This age is younger than that of the peak of granulite metamorphism in the host rocks (1925–1915 Ma) and coincides within error with the age of rutile from granulites (1880–1870 Ma), indicating the time at which cooling to 450 °C occurs. Emplacement in the cooled rocks is confirmed by the detection of quenching zones in clinopyroxenites around granulite xenoliths. Magnetite ores, as well as mineralized pyroxenites with sulfide disseminations, are formed during a late stage of the complex development, as suggested by active assimilation of granulite xenoliths by these rocks. The isotopic age of mineralized pyroxenites enriched in PGEs is 1832 ± 35 Ma (εNd(T) = –2.0), while the age of magnetite ores is 1823 ± 19 Ma (εNd(T) = –2.5). Thus, the obtained isotopic data indicate that the emplacement of the Porya Guba complex and probably other small mafic–ultramafic intrusions in the Kolvitsa mélange granulites took place after the end of the Lapland–Kola collision.

Impact of hypertension education on knowledge and healthy lifestyle practices among Indian adolescents: A quasi-experimental study

Background: This study aimed to establish the effectiveness of a hypertension knowledge education intervention among Indian adolescents to foster lifestyle changes aimed at preventing hypertension. Methods: The Hypertension Knowledge Test (HKT) was used to assess changes in knowledge using a repeated-measures one-way analysis of variance (ANOVA). The Healthy Lifestyle Practice Scale for Children and Adolescents (HELIPSCA) indexed healthy lifestyle practices, with paired t-tests used to compare pre- and post-intervention scores. A two-way mixed ANOVA examined changes in healthy lifestyle practices among adolescents divided in terms of early and late stage of development. Results: Significant mean differences were observed in overall hypertension knowledge across four domains: general awareness, lifestyle factors, causes and care, and medication management and across time periods. There was a significant improvement in HELIPSCA scores post-intervention, particularly among early adolescents. Conclusion: The hypertension knowledge intervention examined in this study was effective in establishing a cognitive base among school children, with knowledge retention observed for 3 months. Moreover, this knowledge increase was associated with a parallel change in improved healthy lifestyle practices, notably among early adolescents. These findings underscore the importance of providing school-based education programmes early in adolescence to promote awareness of chronic illnesses and encourage healthy lifestyle choices.

The H2S-responsive transcription factor ERF.D3 regulates tomato abscisic acid metabolism, leaf senescence, and fruit ripening.

Hydrogen sulfide (H2S) is a signaling molecule that regulates plant senescence. In this study, we found that H2S delays dark-induced senescence in tomato (Solanum lycopersicum) leaves. Transcriptome and RT-qPCR analyses revealed an Ethylene Response Factor ERF.D3 is quickly induced by H2S. H2S also persulfidated ERF.D3 at amino acid residues C115 and C118. CRISPR/Cas9-mediated gene editing and gene overexpression analyses showed that ERF.D3 negatively regulates leaf senescence and fruit ripening. Abscisic acid (ABA) levels were reduced by ERF.D3 overexpression, suggesting ERF.D3 might regulate ABA metabolism. Additionally, the abscisic acid 8'-hydroxylase-encoding gene CYP707A2, which is required for ABA degradation, was identified as an ERF.D3 target gene through transcriptome data, RT-qPCR, dual-luciferase reporter assays and electrophoretic mobility shift assays. ERF.D3 persulfidation enhanced its transcriptional activity towards CYP707A2. Moreover, the E3 ligase RNF217 ubiquitinated ERF.D3, which may accelerate fruit ripening during the late stage of fruit development. Overall, our study provides valuable insights into the roles of a H2S-responsive ERF.D3 and its persulfidation state in delaying leaf senescence and fruit ripening and provides a link between H2S and ABA degradation.

Carbon dioxide injection into the Achimov formations using reinjection technology by the example of Ach3-4 formation in the Novo-Urengoy area of the Urengoy field

The prerequisites for the study are the calculation results for the cycling process, where carbon dioxide is proposed as the injection agent into the Achimov formations instead of dry gas, with the goal of increasing the condensate recovery factor. The work is focused on the efficiency assessment of carbon dioxide reinjection technology and reducing carbon footprint at a late stage of field development. The research object is the Аch3-4 formation within the Novo-Urengoy license area of the Urengoy field. The leading method to identify this problem is the results of the full-scale composite dynamic model in the ECLIPSE 300 format. The model takes into account the history of field development on depletion. The articles deals with two schemes for injecting carbon dioxide into the formation. In the first scheme, pure carbon dioxide is injected in a closed-loop system, but carbon neutrality through storage is not achieved. In the second scheme, carbon dioxide is injected using reinjection technology. Once injection begins, gas production stops. Only the condensate separated from the formation gas during low-temperature separation is sold and sent for further processing. After allocation of the condensate, the mixture of natural gas and carbon dioxide, in a specific proportion, is sent to the compressor station for reinjection into the formation in a gaseous state. Injecting pure carbon dioxide achieves a condensate recovery factor similar to that of gas injection with a 30 % carbon dioxide mixture. However, this option is less economically viable compared to the base and other scenarios due to high capital costs for upgrading the existing gas processing equipment (requiring the construction of an amine treatment unit). With carbon dioxide injection using reinjection technology, in addition to recovering extra condensate that had condensed during natural depletion, a reduction in the carbon footprint is also achieved. To maximize the condensate recovery factor, the optimal concentration of carbon dioxide in the injection mixture has been determined. The optimal timing for the start of injection was identified to maximize gas recovery. Economic efficiency is expected from the additional recovery of condensate trapped in the reservoir and from achieving carbon neutrality through the monetization and storage of carbon dioxide.

Cryodehydration applied to bovine fetal hearts: A model for studying cardiac organogenesis.

The study aimed to standardize the cryodehydration technique for bovine fetal hearts, focusing on optimizing protocols for each developmental stage to preserve morphological characteristics. We analyzed 29 bovine fetal hearts categorized into early, middle, and late developmental stages. These hearts underwent cryodehydration until a 60%-70% reduction in original fluid volume was achieved. Biometric data were recorded and statistically analyzed using Pearson correlation tests for age versus weight and age versus number of cryodehydration sessions. Morphometric comparisons before and after cryodehydration were performed using paired t-tests. In Group I, hearts exhibited well-defined structures, including the atrium cordis, ventriculus cordis, auricula atrii, aorta, truncus pulmonalis, and ramus coronaries arteria, which were preserved in Groups II and III. Additionally, in Group I the heart had a conical or flat apex cordis, whereas those in Groups II and III had a more pronounced apex. The average number of cryodehydration sessions required was 9.38 (±1.2) days for Group I, 12.37 (±1.4) days for Group II, and 15 days for Group III. A positive correlation was found between age and sample weight, indicating that more developed hearts were heavier. Similarly, there was a positive correlation between gestational age and the number of cryodehydration sessions, suggesting that more advanced stages required more cryodehydration sessions. Paired t-tests demonstrated high statistical significance in the morphometric parameters before and after cryodehydration, indicating a loss of mass during dehydration. However, there was no alteration in the macroscopic structure of the hearts, which remained morphologically preserved. In conclusion, cryodehydration shows promise for preserving and analyzing the external morphological characteristics of bovine fetal cardiac development. It also provides lightweight, odorless, and easy-to-handle specimens ideal for detailed morphological studies and offers a unique perspective for investigating cardiac morphology in biological research contexts.

Maize Abiotic Stress Treatments in Controlled Environments.

Maize (Zea mays) is one of the world's most important crops, providing food for humans and livestock and serving as a bioenergy source. Climate change and the resulting abiotic stressors in the field reduce crop yields, threatening food security and the global economy. Water deficit (i.e., drought), heat, and insufficient nutrients (e.g., nitrogen and phosphorus) are major environmental stressors that affect maize yields, and impact growth and development at all stages of the plant life cycle. Understanding the biological processes underlying these responses in maize has the potential to increase yields in the face of abiotic stress. Optimizing individual or combined abiotic stress treatments in controlled environments reduces potential noise in data collection that can be present under less controlled growth conditions. Here, we describe methods and conditions for controlled abiotic stress treatments and associated controls during early vegetative growth of maize, conducted in greenhouses or growth chambers. This includes the environmental conditions, equipment, soil preparation, and intensity and duration of heat, drought, nitrogen deficiency, and phosphorous deficiency. Controlled experiments at early growth stages are informative for future in-field studies that require greater labor and inputs, saving researchers time and growing space, and thus research funds, before testing plants across later stages of development. We suggest that stress treatments be severe enough to result in a measurable phenotype, but not so severe that all plants die prior to sample collection. This protocol is designed to set important standards for replicable research in maize.

Integration of Geological Model and Numerical Simulation Technique to Characterize the Remaining Oil of Fractured Biogenic Limestone Reservoirs

AbstractFine geological modeling leads to accurate reservoirs numerical simulations. Fractured biogenic limestone has abundant storage spaces and flow paths to accumulate oil and gas. The complexity and diversity of fractured biogenic limestone also lead to challenges in accurately characterizing its pore volume and remaining oil. This investigation aimed to enhance the understanding of fractured biotite reservoir properties via geological modeling. Numerical simulations were used to characterize the remaining oil during the late stage of field development. Considering the differences in porosity and permeability between fractures and matrix, a facies-controlled stochastic modeling technique was used to establish a dual-porosity and dual-permeability (DPDP) model for numerical simulation. Core information, logging data, and multiple seismic attributes were combined to guide low-level sequence fault interpretation for tectonic refinement. Based on classified seismic inversion, sedimentary phases were reconstructed. A discrete fracture network (DFN) model was obtained based on fracture occurrences and density models. The optimized discrete adjoint (ODA) algorithm was utilized to calibrate model parameters. The findings revealed that dense tectonic fractures develop in thick biogenic limestone areas. Combined with advanced reservoir simulation technology, these findings suggest that areas of thicker biogenic limestone were consistent with areas of higher fracture matrix conductivity multipliers. The remaining oil distribution patterns were investigated, and to deploy new wells was guided. Therefore, it is essential to better understand the tectonic characteristics of fractured biogenic limestone reservoirs and their remaining oil distribution patterns by integrating multiple sources of information and mastering advanced reservoir simulation technology for oilfield development.

Developmental characteristics of cutaneous telocytes in late embryos of the silky fowl.

Telocytes (TCs) have been identified in various animals. However, information on TCs in the embryos is still very limited. In this work, the developing skin of the silky fowl was sampled for TCs identification by histology, immunohistochemistry and transmission electron microscopy. In addition, morphological parameters of cutaneous TCs and their location relationships were measured using a morphometry software - ImageJ (FiJi). At the 12th, 16th and 20th day of incubation, in the embryonic skin, telocyte-like cells (TC-L) were observed in the dermis. TCs were PDGFRα+ at the 12th, 16th and 20th day of incubation, but showed CD34+ only at 20th day of incubation in the embryonic dermis. Ultrastructurally, TCs were observed in the dermis at all late embryonic developmental stages. TCs established the homocellular contacts/plasmalemmal adhesion with each other. TCs established heterocellular contacts with melanocytes at 20th day of incubation in the dermis. In addition, the intracellular microvesicles were present in the cytoplasm of TCs. The extracellular microvesicles/exosomes were in close proximity to the TCs. The results confirmed that the locations, immunophenotypes, structural characteristics and relationships of TCs, and revealed the developmental characteristics of cutaneous TCs in late silky fowl embryos.

Towards a double bell theory of regional disparities

AbstractDespite the large attention given to regional disparities, a conceptual framework simultaneously linking the inter- and intra-regional development processes over time is still missing. A vast set of empirical analyses on their trends indeed exists. In most cases, it witnesses the presence of the famous Williamson’s inverted U-shaped relation between GDP per capita and regional income inequalities, and of its augmented shape where the inverted U turns upward again at later stages of development. The paper has the aim to present a conceptual framework on the interlinkages between inter- and intra-regional disparity trends, highlighting the influence that one exerts over the other. It does so claiming that their joint analysis can provide an explanation of situations “against conventional wisdom” and can overcome the simplistic idea that if inter-regional convergence occurs, social equity is achieved. Empirical evidence is provided in the case of European regions. The paper has a normative value, in that an interpretation of the concurrent inequality trends at different levels can lead to more efficient normative interventions, avoiding misallocation of financial resources at sub-regional level.

IL-4 promotes chondrogenesis of bone marrow mesenchymal stem cellsand blockade of IL-4Rα retards the endochondral ossification during rat embryonic bone development.

Interleukin-4 (IL-4)/IL-4 receptor alpha (IL-4Rα) signalling pathways play important roles in the complex process of bone formation and bone remodelling. However, whether IL-4/IL-4Rα participates in skeletogenesis during embryonic development is not completely understood. We used the anti-IL-4Rα monoclonal antibody (anti-IL-4Rα mAb) as a powerful investigational tool to evaluate the potential roles of IL-4/IL-4Rα in the chondrogenic differentiation of rat bone marrow mesenchymal stem cells (BMSCs) in vitro. Simultaneously, we explored the effect of IL-4/IL-4Rα on bone ossification during rat embryo-fetal development. In this study, we found that, compared to the control group, IL-4 can significantly promote the chondrogenic differentiation of BMSCs. Furthermore, following exposure to anti-IL-4Rα mAb in pregnant rats, unexpected phenomena were observed in fetal bone development, including non-ossification of the fetal sternum, an incomplete ossification centre in long bones and a reduced number of ossification points in digit (toe) bones. To further investigate the underlying mechanism of the phenotype, we studied the rat sternum as the target organ, starting from different time points of sternum development in the embryonic stage. The results indicated that the retardation mainly occurred in the middle and late stages of embryonic development. This retardation was characterized by the inhibition of the differentiation process of mesenchymal stem cells into chondrocytes, resulting in reduced angiogenesis near the ossification centre, failure of osteoblasts to invade the centre of the cartilage body with the blood vessels and delayed formation of the primary ossification centre (POC). Overall, our study demonstrated the significant function of IL-4/IL-4Rα in chondrogenic differentiation of BMSCs and bone ossification during embryo-fetal development.