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Degradasi lahan mangrove menyebabkan perubahan pada garis pantai. Wilayah pesisir Kecamatan Talibura, Kabupaten Sikka merupakan salah satu wilayah yang memiliki ekosistem mangrove. Keberadaan penduduk di wilayah ini, menyebabkan adanya interaksi antara penduduk dengan ekosistem mangrove sehingga terjadinya degradasi pada ekosistem mangrove. Pada wilayah pesisir Kecamatan Talibura, belum ada sama sekali penelitian yang menunjukkan perubahan tutupan lahan mangrove dan garis pantai selama 30 tahun. Penelitian ini bertujuan untuk mengetahui perubahan tutupan lahan mangrove dan garis pantai pada tahun 1990-2019 di Kecamatan Talibura. Tutupan lahan mangrove diperoleh menggunakan metode Supervised Classification dan untuk mengetahui perubahan garis pantai digunakan metode DSAS yang menghitung statistik laju perubahan garis pantai dari data citra landsat perekaman tahun 1990, 2004, dan 2019. Hasil penelitian menunjukkan adanya degradasi mangrove 60,84 ha periode waktu 1990-2004 dan mengalami penambahan 2,43 ha, yang dapat terlihat adanya abrasi di daerah degradasi mangrove dengan nilai tertinggi -487,54 m dan nilai akresi tertinggi 307,45 m di daerah yang masih terjaga ekosistem mangrovenya selama 30 tahun.

Adrenal hemorrhage is a rare, but important, diagnosis to recognize, in particular when there is involvement of both adrenal glands. Bilateral adrenal hemorrhage can in fact lead to adrenal insufficiency, with dramatic consequences if not promptly recognized and treated. It is normally caused by systemic conditions that lead to the vasoconstriction and thrombosis of the adrenal vein. Oftentimes, the clinical diagnosis of this condition can be very challenging, as its signs and symptoms are generalized and nonspecific (abdominal pain, nausea, and fatigue). Here, we present the cases of two patients admitted to the Emergency Department in 2016 and 2022 with acute abdominal pain, having recently undergone surgery and subsequently prescribed low-molecular-weight heparin. In both cases, laboratory results revealed neutrophilic leukocytosis and an unexplained anemia. Due to the persistence of abdominal pain despite medication, a CT scan was performed, showing an enlargement of both adrenal glands suggestive of bilateral adrenal hemorrhage. Adrenal function was tested that correlated with a diagnosis of adrenal insufficiency, and both patients were promptly treated with parenteral hydrocortisone as a result. On 5 years’ follow-up from the acute event, the second patient’s adrenal function had returned to normal, and he has not needed further adrenal replacement therapy; the first patient however demonstrated persistence of adrenal failure requiring replacement therapy. In this paper, through our experience and a literature analysis, we will aim to outline some clues to identify patients at potential risk of bilateral adrenal hemorrhage.

Genomes represent the starting point of genetic studies. Since the discovery of DNA structure, scientists have devoted great efforts to determine their sequence in an exact way. In this review we provide a comprehensive historical background of the improvements in DNA sequencing technologies that have accompanied the major milestones in genome sequencing and assembly, ranging from early sequencing methods to Next-Generation Sequencing platforms. We then focus on the advantages and challenges of the current technologies and approaches, collectively known as Third Generation Sequencing. As these technical advancements have been accompanied by progress in analytical methods, we also review the bioinformatic tools currently employed in de novo genome assembly, as well as some applications of Third Generation Sequencing technologies and high-quality reference genomes.

We present a genome assembly from an individual female Caprimulgus europaeus (the European nightjar; Chordata; Aves; Caprimulgiformes; Caprimulgidae). The genome sequence is 1,178 megabases in span. The majority of the assembly (99.33%) is scaffolded into 37 chromosomal pseudomolecules, including the W and Z sex chromosomes.

Ferroelectric wurtzite‐type aluminum scandium nitride (Al1−xScxN) presents unique properties that can enhance the performance of non‐volatile memory technologies. The realization of the full potential of Al1−xScxN requires a comprehensive understanding of the mechanism of polarization reversal and domain structure dynamics involved in the ferroelectric switching process. In this work, transient current integration measurements performed by a pulse switching method are combined with domain imaging by piezoresponse force microscopy (PFM) to investigate the kinetics of domain nucleation and wall motion during polarization reversal in Al0.85Sc0.15N capacitors. In the studied electric field range (from 4.4 to 5.6 MV cm−1), ferroelectric switching proceeds via domain nucleation and wall movement. The currently available phenomenological models are shown to not fully capture all the details of the complex dynamics of polarization reversal in Al0.85Sc0.15N. PFM reveals a non‐linear increase of both domain nucleation rate and lateral wall velocity during the switching process, as well as the dependency of the domain pattern on the polarization reversal direction. A continuously faster N‐ to M‐polar switching upon cycling is reported and ascribed to an increasing number of M‐polar nucleation sites and density of domain walls. [ABSTRACT FROM AUTHOR]

Primary cilia are commonly found on most quiescent, terminally differentiated cells and play a major role in the regulation of the cell cycle, cell motility, sensing, and cell–cell communication. Alterations in ciliogenesis and cilia maintenance are causative of several human diseases, collectively known as ciliopathies. A key determinant of primary cilia is the histone deacetylase HDAC6, which regulates their length and resorption and whose distribution is regulated by the death inducer-obliterator 3 (Dido3). Here, we report that the atypical protein kinase Haspin is a key regulator of cilia dynamics. Cells defective in Haspin activity exhibit longer primary cilia and a strong delay in cilia resorption upon cell cycle reentry. We show that Haspin is active in quiescent cells, where it phosphorylates threonine 3 of histone H3, a known mitotic Haspin substrate. Forcing Dido3 detachment from the chromatin prevents Haspin inhibition from impacting cilia dynamics, suggesting that Haspin activity is required for the relocalization of Dido3–HDAC6 to the basal body. Exploiting the zebrafish model, we confirmed the physiological relevance of this mechanism. Our observations shed light on a novel player, Haspin, in the mechanisms that govern the determination of cilia length and the homeostasis of mature cilia.

The emergence of ferroelectric and antiferroelectric properties in the semiconductor industry's most prominent high‐k dielectrics, HfO2 and ZrO2, is leading to technology developments unanticipated a decade ago. Yet the failure to clearly distinguish ferroelectric from antiferroelectric behavior is impeding progress. Band‐excitation piezoresponse force microscopy and molecular dynamics are used to elucidate the nanoscale electric field‐induced phase transitions present in ZrO2‐based antiferroelectrics. Antiferroelectric ZrO2 is clearly distinguished from a closely resembling pinched La‐doped HfO2 ferroelectric. Crystalline grains in the range of 3 – 20 nm are imaged independently undergoing reversible electric field induced phase transitions. The electrically accessible nanoscale phase transitions discovered in this study open up an unprecedented paradigm for the development of new nanoelectronic devices. [ABSTRACT FROM AUTHOR]

The in‐memory computing paradigm aims at overcoming the intrinsic inefficiencies of Von‐Neumann computers by reducing the data‐transport per arithmetic operation. Crossbar arrays of multilevel memristive devices enable efficient calculations of matrix‐vector‐multiplications, an operation extensively called on in artificial intelligence (AI) tasks. Resistive random‐access memories (ReRAMs) are promising candidate devices for such applications. However, they generally exhibit large stochasticity and device‐to‐device variability. The integration of a sub‐stoichiometric metal‐oxide within the ReRAM stack can improve the resistive switching graduality and stochasticity. To this purpose, a conductive TaOx layer is developed and stacked on HfO2 between TiN electrodes, to create a complementary metal‐oxide‐semiconductor‐compatible ReRAM structure. This device shows accumulative conductance updates in both directions, as required for training neural networks. Moreover, by reducing the TaOx thickness and by increasing its resistivity, the device resistive states increase, as required for reduced power consumption. An electric field‐driven TaOx oxidation/reduction is responsible for the ReRAM switching. To demonstrate the potential of the optimized TaOx/HfO2 devices, the training of a fully‐connected neural network on the Modified National Institute of Standards and Technology database dataset is simulated and benchmarked against a full precision digital implementation. [ABSTRACT FROM AUTHOR]

The barn swallow (Hirundo rustica) poses a number of fascinating scientific questions, including the taxonomic status of postulated subspecies. Here, we obtained and assessed the sequence variation of 411 complete mitogenomes, mainly from the European H. r. rustica , but other subspecies as well. In almost every case, we observed subspecies-specific haplogroups, which we employed together with estimated radiation times to postulate a model for the geographical and temporal worldwide spread of the species. The female barn swallow carrying the Hirundo rustica ancestral mitogenome left Africa (or its vicinity) around 280 thousand years ago (kya), and her descendants expanded first into Eurasia and then, at least 51 kya, into the Americas, from where a relatively recent (<20 kya) back migration to Asia took place. The exception to the haplogroup subspecies specificity is represented by the sedentary Levantine H. r. transitiva that extensively shares haplogroup A with the migratory European H. r. rustica and, to a lesser extent, haplogroup B with the Egyptian H. r. savignii. Our data indicate that rustica and transitiva most likely derive from a sedentary Levantine population source that split at the end of the Younger Dryas (YD) (11.7 kya). Since then, however, transitiva received genetic inputs from and admixed with both the closely related rustica and the adjacent savignii. Demographic analyses confirm this species' strong link with climate fluctuations and human activities making it an excellent indicator for monitoring and assessing the impact of current global changes on wildlife. [ABSTRACT FROM AUTHOR]

The emergence of ferroelectric and antiferroelectric properties in the semiconductor industry's most prominent high‐k dielectrics, HfO2 and ZrO2, is leading to technology developments unanticipated a decade ago. Yet the failure to clearly distinguish ferroelectric from antiferroelectric behavior is impeding progress. Band‐excitation piezoresponse force microscopy and molecular dynamics are used to elucidate the nanoscale electric field‐induced phase transitions present in ZrO2‐based antiferroelectrics. Antiferroelectric ZrO2 is clearly distinguished from a closely resembling pinched La‐doped HfO2 ferroelectric. Crystalline grains in the range of 3 – 20 nm are imaged independently undergoing reversible electric field induced phase transitions. The electrically accessible nanoscale phase transitions discovered in this study open up an unprecedented paradigm for the development of new nanoelectronic devices. [ABSTRACT FROM AUTHOR]

The capability to reliably program partial polarization states with nanosecond programming speed and femtojoule energies per bit in ferroelectrics makes them an ideal candidate to realize multibit memory elements for high-density crossbar arrays, which could enable neural network models with a large number of parameters at the edge. However, a thorough understanding of the domain switching dynamics involved in the polarization reversal is required to achieve full control of the multibit capability. Transient current integration measurements are adopted to investigate the domain dynamics in aluminum scandium nitride (Al 0.85 Sc 0.15 N) and hafnium zirconium oxide (Hf 0.5 Zr 0.5 O 2 ). The switching dynamics are correlated to the crystal structure of the films. The contributions of domain nucleation and domain wall motion are decoupled by analyzing the rate of change of the time-dependent normalized switched polarization. Thermally activated creep domain wall motion characterizes the Al 0.85 Sc 0.15 N switching dynamics. The statistics of independently nucleating domains and the domain wall creep motion in Hf 0.5 Zr 0.5 O 2 are associated with the spatially inhomogeneous distribution of local switching field due to polymorphism, absence of preferential crystallite orientation, as well as defects and charges that can be located at the grain boundaries. The c -axis texture, single-phase nature, and strong likelihood of less fabrication process-induced defects contribute to the homogeneity of the local switching field in Al 0.85 Sc 0.15 N. Nonetheless, defects generated and redistributed upon bipolar electric field switching cycling result in Al 0.85 Sc 0.15 N domain wall pinning. The wake-up effect in Hf 0.5 Zr 0.5 O 2 is explained thorough the continuous addition of switchable regions associated with two independent distributions of characteristic switching times.

Ferroelectric wurtzite-type aluminum scandium nitride (Al 1-x Sc x N) presents unique properties that can enhance the performance of non-volatile memory technologies. The realization of the full potential of Al 1-x Sc x N requires a comprehensive understanding of the mechanism of polarization reversal and domain structure dynamics involved in the ferroelectric switching process. In this work, transient current integration measurements performed by a pulse switching method are combined with domain imaging by piezoresponse force microscopy (PFM) to investigate the kinetics of domain nucleation and wall motion during polarization reversal in Al 0.85 Sc 0.15 N capacitors. In the studied electric field range (from 4.4 to 5.6 MV cm -1 ), ferroelectric switching proceeds via domain nucleation and wall movement. The currently available phenomenological models are shown to not fully capture all the details of the complex dynamics of polarization reversal in Al 0.85 Sc 0.15 N. PFM reveals a non-linear increase of both domain nucleation rate and lateral wall velocity during the switching process, as well as the dependency of the domain pattern on the polarization reversal direction. A continuously faster N- to M-polar switching upon cycling is reported and ascribed to an increasing number of M-polar nucleation sites and density of domain walls., (© 2024 The Authors. Advanced Science published by Wiley‐VCH GmbH.)

Aluminum scandium nitride (Al 1- x Sc x N), with its large remanent polarization, is an attractive material for high-density ferroelectric random-access memories. However, the cycling endurance of Al 1- x Sc x N ferroelectric capacitors is far below what can be achieved in other ferroelectric materials. Understanding the nature and dynamics of the breakdown mechanism is of the utmost importance for improving memory reliability. The breakdown phenomenon in ferroelectric Al 1- x Sc x N is proposed to be an impulse thermal filamentary-driven process along preferential defective pathways. For the first time, stable and robust bipolar filamentary resistive switching in ferroelectric Al 1- x Sc x N is reported. A hot atom damage defect generation model illustrates how filament formation and ferroelectric switching are connected. The model reveals the tendency of the ferroelectric wurtzite-type Al 1- x Sc x N system to reach internal symmetry with bipolar electric field cycling. Defects generated from bipolar electric field cycling influence both the energy barrier between the polarization states and that required for the filament formation.

We present a genome assembly from an individual female Caprimulgus europaeus (the European nightjar; Chordata; Aves; Caprimulgiformes; Caprimulgidae). The genome sequence is 1,178 megabases in span. The majority of the assembly (99.33%) is scaffolded into 37 chromosomal pseudomolecules, including the W and Z sex chromosomes., Competing Interests: No competing interests were disclosed., (Copyright: © 2021 Secomandi S et al.)

Genomes represent the starting point of genetic studies. Since the discovery of DNA structure, scientists have devoted great efforts to determine their sequence in an exact way. In this review we provide a comprehensive historical background of the improvements in DNA sequencing technologies that have accompanied the major milestones in genome sequencing and assembly, ranging from early sequencing methods to Next-Generation Sequencing platforms. We then focus on the advantages and challenges of the current technologies and approaches, collectively known as Third Generation Sequencing. As these technical advancements have been accompanied by progress in analytical methods, we also review the bioinformatic tools currently employed in de novo genome assembly, as well as some applications of Third Generation Sequencing technologies and high-quality reference genomes., Competing Interests: G.F. had one travel sponsored by Bionano Genomics. A.M.G., G.R.G. and L.G. declare no conflicts of interest., (© 2019 The Authors.)