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يتناول كتاب (المعجم الموسوعي الجديد في علوم اللغة) والذي قام بتأليفه (مجموع من المؤلفين) في حوالي (746) صفحة من القطع المتوسط موضوع (معاجم علم اللغة) مستعرضا المحتويات التالية : الأنحاء العامة، اللسانيات التاريخية في القرن التاسع عشر، السوسيرية، الغلوسيماتيقا، الوظيفية، التوزيعية، الآلية النفسية للغة، المعيار، الاعتباطية، الآنية والزمانية، القالبية، المرجع، التخييل ؛ المفاهيم الخاصة : الوحدات غير الدالة، العروض اللساني، الوحدات الدالة، أقسام الكلام، الوظائف التركيبية، القواعد والمبادئ التوليدية.

Eukaryotic life appears to have flourished surprisingly late in the history of our planet. This view is based on the low diversity of diagnostic eukaryotic fossils in marine sediments of mid-Proterozoic age (around 1,600 to 800 million years ago) and an absence of steranes, the molecular fossils of eukaryotic membrane sterols 1 , 2 . This scarcity of eukaryotic remains is difficult to reconcile with molecular clocks that suggest that the last eukaryotic common ancestor (LECA) had already emerged between around 1,200 and more than 1,800 million years ago. LECA, in turn, must have been preceded by stem-group eukaryotic forms by several hundred million years 3 . Here we report the discovery of abundant protosteroids in sedimentary rocks of mid-Proterozoic age. These primordial compounds had previously remained unnoticed because their structures represent early intermediates of the modern sterol biosynthetic pathway, as predicted by Konrad Bloch 4 . The protosteroids reveal an ecologically prominent ‘protosterol biota’ that was widespread and abundant in aquatic environments from at least 1,640 to around 800 million years ago and that probably comprised ancient protosterol-producing bacteria and deep-branching stem-group eukaryotes. Modern eukaryotes started to appear in the Tonian period (1,000 to 720 million years ago), fuelled by the proliferation of red algae (rhodophytes) by around 800 million years ago. This ‘Tonian transformation’ emerges as one of the most profound ecological turning points in the Earth’s history. Analysis of sedimentary rocks from the mid-Proterozoic interval reveals traces of protosteroids, suggesting the widespread presence of stem-group eukaryotes that predated and co-existed with the crown-group ancestors of modern eukaryotes.

A new mean sea surface (MSS) was determined by focusing on the accuracy provided by exact-repeat altimetric missions (ERM) and the high spatial coverage of geodetic (or drifting) missions. The goal was to obtain a high-resolution MSS that would provide centimeter-level precision. Particular attention was paid to the homogeneity of the oceanic content of this MSS, and specific processing was also carried out, particularly on the data from the geodetic missions. For instance, CryoSat-2 and SARAL/AltiKa data sampled at high frequencies were enhanced using a dedicated filtering process and corrected from oceanic variability using the results of the objective analysis of sea-level anomalies provided by DUACS multi-missions gridded sea-level anomalies fields (MSLA). Particular attention was also paid to the Arctic area by combining traditional sea-surface height (SSH) with the sea levels estimated within fractures in the ice (leads). The MSS was determined using a local least-squares collocation technique, which provided an estimation of the calibrated error. Furthermore, our technique takes into account altimetric noises, ocean-variability-correlated noises, and along-track biases, which are determined independently for each observation. Moreover, variable cross-covariance models were fitted locally for a more precise determination of the shortest wavelengths, which were shorter than 30 km. The validations performed on this new MSS showed an improvement in the finest topographic structures, with amplitudes exceeding several cm, while also continuing to refine the correction of the oceanic variability. Overall, the analysis of the precision of this new CNES_CLS 2022 MSS revealed an improvement of 40% compared to the previous model, from 2015.

Geochemical and isotopic analysis of bitumen lining potsherds from the al-Qusur monastery (second half of the 7th c. CE and the middle of the 9th c. CE), at the central part of Failaka Island (Kuwait Bay), confirms the presence of two distinct compositional categories that can be matched to contemporary sources from two different areas of Iran: the Kermanshah province on one side, and the Khuzestan–Fars–Busher provinces on the other side. Potsherds comprise different types: TORP-S amphorae, TORP-C amphorae, SPORC storage jar, turquoise alkaline-glazed jar (TURQ.T), and CREAC jar. There is no relationship between the type of potsherd and the origin of bitumen. The bitumen coating SPORC jar, first identified as a kind of juice strainer to filter the «garum-like juice», was examined in greater details to try to identify traces of fish sauce mentioned in the Arabic kitchen books as ‘murri’, and quite similar to the Roman garum. The mineralogical analysis exhibits the classical minerals of archaeological mixtures (quartz, calcite, dolomite) and no halite. Hydrocarbons, alcohols, and methyl esters show a typical biodegraded bitumen signature but no fatty acids and terpenoids. It seems that the bitumen matrix has not adsorbed any molecules from the presumed «garum» filtered in the basin.

Since the 2010 launch of Cryosat‐2, a new generation of altimeters, referred to as SAR altimetry, has emerged and partially replaced the previous conventional altimeters known as Low Resolution Mode (LRM) altimetry. A surface slope correction has been previously developed for LRM altimetry. However, the differences in the way the two altimeters work, and in particular their radar footprint, make LRM altimeter slope correction inapplicable to SAR altimetry. Thus, in this paper, a slope correction model is provided for SAR altimetry, derived from the LRM‐based approach. The shape of the SAR footprint induces that height correction depends on each satellite mission. Consequently, a generic method allowing to generate global maps of height correction for distinct missions is provided. The maps are computed for the Sentinel‐6A mission and the importance of correcting this effect for SAR altimetry is highlighted by studying the sea surface height anomaly biases between Sentinel‐6A SAR and LRM measurements. Finally, it is shown that applying the slope correction to Sentinel‐6A SAR mode sea surface height anomaly measurements enhances their consistency with the latest Mean Sea Surface (MSS) model, reducing the root mean square error between the sea surface height anomaly and the MSS model by up to 1 cm. Plain Language Summary Satellite altimeters measure sea surface height, in order to monitor for instance ocean circulation and topography. A new generation of altimeters, called SAR altimeters, has replaced older models known as Low Resolution Mode (LRM) altimeters. However, because SAR altimeters operate differently, corrections developed for LRM altimeters cannot be directly applied to them. One key correction accounts for the effect of sea surface slopes on height measurements. This study develops a height correction method specifically for SAR altimetry, based on an approach previously used for LRM altimeters. The correction varies depending on the satellite mission, so a general method is introduced to create global height correction maps for different SAR altimeters missions. The method is demonstrated using data from the Sentinel‐6A satellite. Applying the new correction to Sentinel‐6A SAR data significantly reduces biases in sea surface height anomaly measurements compared to LRM data. The correction also improves agreement between SAR altimetry data and the most recent Mean Sea Surface model. This study provides a height correction for SAR altimetry, making it more consistent with existing sea surface height data. In the future, this method could help better integrate LRM and SAR altimetry measurements, improving ocean studies and products. Key Points A height correction for SAR altimetry, accounting for the sea surface slope effect, has been derived from the Low Resolution Mode (LRM)‐based approach Applying this correction significantly reduces sea surface height anomaly biases between Sentinel‐6A SAR and LRM modes This correction enhances SAR altimetry consistency with Mean Sea Surface models and could improve the fusion of LRM and SAR data for ocean studies

Elucidating the lipidome of Archaea is essential to understand their tolerance to extreme environmental conditions. Previous characterizations of the lipid composition of Pyrococcus species, a model genus of hyperthermophilic archaea belonging to the Thermococcales order, led to conflicting results, which hindered the comprehension of their membrane structure and the putative adaptive role of their lipids. In an effort to clarify the lipid composition data of the Pyrococcus genus, we thoroughly investigated the distribution of both the core lipids (CL) and intact polar lipids (IPL) of the model Pyrococcus furiosus and, for the first time, of Pyrococcus yayanosii, the sole obligate piezophilic hyperthermophilic archaeon known to date. We showed a low diversity of IPL in the lipid extract of P. furiosus, which nonetheless allowed the first report of phosphatidyl inositol-based glycerol mono- and trialkyl glycerol tetraethers. With up to 13 different CL structures identified, the acid methanolysis of Pyrococcus furiosus revealed an unprecedented CL diversity and showed strong discrepancies with the IPL compositions reported here and in previous studies. By contrast, P. yayanosii displayed fewer CL structures but a much wider variety of polar heads. Our results showed severe inconsistencies between IPL and CL relative abundances. Such differences highlight the diversity and complexity of the Pyrococcus plasma membrane composition and demonstrate that a large part of its lipids remains uncharacterized. Reassessing the lipid composition of model archaea should lead to a better understanding of the structural diversity of their lipidome and of their physiological and adaptive functions.

Hypersaline environments, including brines and brine inclusions of evaporite crystals, are currently of great interest due to their unique preservation properties for the search for terrestrial and potentially extraterrestrial biosignatures of ancient life. However, much is still unclear about the specific effects that dictate the preservation properties of brines. Here we present the first insights into the preservation of cell envelope fragments in brines, characterizing the relative contributions of brine composition, UV photochemistry, and cellular macromolecules on biosignature preservation. Cell envelopes from the model halophile Halobacterium salinarum were used to simulate dead microbial cellular remains in hypersaline environments based on life as we currently know it. Using different Early Earth and Mars analogue brines, we show that acidic and NaCl-dominated brine compositions are more predisposed to preserving complex biosignatures from UV degradation, but that the composition of the biological material also influences this preservation. Furthermore, a combinatory effect between chaotropicity and photochemistry occurs, with the relative importance of each being brine-specific. These results provide an experimental framework for biosignature detection in hypersaline environments, emphasizing the need for laboratory simulations to evaluate preservation properties of each potential brine environment, on Earth and elsewhere in the solar system. This study investigates the relative contributions of brine composition and UV photochemistry in biosignature preservation in hypersaline environments on Earth and in space using Halobacterium salinarum cell envelopes.

A seed recovered during archaeological excavations of a cave in the Judean desert was germinated, with radiocarbon analysis indicating an age of 993 CE– 1202 calCE. DNA sequencing and phylogenetic analysis identified the seedling as belonging to the angiosperm genus Commiphora Jacq., sister to three Southern African Commiphora species, but unique from all other species sampled to date. The germinated seedling was not closely related to Commiphora species commonly harvested for their fragrant oleoresins including Commiphora gileadensis (L.) C.Chr., candidate for the locally extinct “Judean Balsam” or “Balm of Gilead” of antiquity. GC-MS analysis revealed minimal fragrant compounds but abundance of those associated with multi-target bioactivity and a previously undescribed glycolipid compound series. Several hypotheses are offered to explain the origins, implications and ethnobotanical significance of this unknown Commiphora sp., to the best of our knowledge the first identified from an archaeological site in this region, including identification with a resin producing tree mentioned in Biblical sources and possible agricultural relationship with the historic Judean Balsam. Germination of an ancient seed from the Judean desert, confirmed by DNA sequencing and phylogenetic analysis as belonging to an unknown Commiphora sp., contained abundant bioactive compounds, suggesting identification with a resin-producing tree mentioned in Biblical sources.

Reactive oxygen species (ROS) and mitochondrial dysfunction play a major role in skin aging. Due to Tropaeolum majus’ suggested protective actions against ROS, a link between T. majus extract and increased cytoglobin (CYGB) expression was evaluated for cultured skin cells. Human dermal fibroblasts and keratinocytes were treated with 0.5% v/v T. majus extract and the effect of this treatment on the expression of CYGB and on a range of cellular markers of aging were evaluated. In fibroblasts, the treatment with the extract was associated with an increase in CYGB levels. It also decreased ROS concentrations, improved the function of mitochondria, and stimulated the synthesis of collagen and elastin. Moreover, it downregulated a set of genes controlling the terminal differentiation of keratinocytes. T. majus extract activates oxygen transport within natural killer cells and thus enhances their activity, suggesting a potential senolytic effect. This extract seemed to exert a protective effect on various aging pathways such as ROS production, mitochondrial dysfunction, and collagen homeostasis, playing a promising role against skin aging.

Highly cracked and isomerized archaeal lipids and bacterial lipids, structurally changed by thermal stress, are present in solvent extracts of 2,707- to 2,685-million-year-old (Ma) metasedimentary rocks from Timmins, ON, Canada. These lipids appear in conventional gas chromatograms as unresolved complex mixtures and include cyclic and acyclic biphytanes, C₃₆-C₃₉ derivatives of the biphytanes, and C₃₁-C₃₅ extended hopanes. Biphytane and extended hopanes are also found in high-pressure catalytic hydrogenation products released from solvent-extracted sediments, indicating that archaea and bacteria were present in Late Archean sedimentary environments. Postdepositional, hydrothermal gold mineralization and graphite precipitation occurred before metamorphism (≈2,665 Ma). Late Archean metamorphism significantly reduced the kerogen's adsorptive capacity and severely restricted sediment porosity, limiting the potential for post-Archean additions of organic matter to the samples. Argillites exposed to hydrothermal gold mineralization have disproportionately high concentrations of extractable archaeal and bacterial lipids relative to what is releasable from their respective high-pressure catalytic hydrogenation product and what is observed for argillites deposited away from these hydrothermal settings. The addition of these lipids to the sediments likely results from a Late Archean subsurface hydrothermal biosphere of archaea and bacteria.