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In many modern applications, it is important to understand mechanisms of non-equilibrium chemistry and physics that are driven by low energy ion bombardment of solid surfaces. However, the study of these processes has been challenging as it demands a relatively unique balance between chemical fidelity and computational cost. To this end, we have proposed and constructed a new, high-throughput simulation pipeline based on density functional tight binding simulations. Additionally, we have extended the parameter set pbc-0-3 with the addition of Ar, thereby enabling the simulation of Ar bombardment. This pipeline was then applied to study the structural and compositional evolution of silicon nitride (SiN) under Ar bombardment. We identified a possible rate limiting step of bombardment-driven sputtering of SiN and suggested underlying mechanisms of Si and N removal. Damage from the bombardment, including generation of surface defects and Ar implantation, are further discussed. These findings and the newly developed simulation framework will serve as a useful foundation for further research in processes driven by ion bombardment. [ABSTRACT FROM AUTHOR]

Hornworts are a deeply diverged lineage of bryophytes and a sister lineage to mosses and liverworts. Hornworts have an array of unique features that can be leveraged to illuminate not only the early evolution of land plants, but also alternative paths for nitrogen and carbon assimilation via cyanobacterial symbiosis and a pyrenoid-based CO2-concentrating mechanism (CCM), respectively. Despite this, hornworts are one of the few plant lineages with limited available genetic tools. Here we report an efficient biolistics method for generating transient expression and stable transgenic lines in the model hornwort, Anthoceros agrestis. An average of 569 (±268) cells showed transient expression per bombardment, with green fluorescent protein expression observed within 48–72 h. A total of 81 stably transformed lines were recovered across three separate experiments, averaging six lines per bombardment. We followed the same method to transiently transform nine additional hornwort species, and obtained stable transformants from one. This method was further used to verify the localization of Rubisco and Rubisco activase in pyrenoids, which are central proteins for CCM function. Together, our biolistics approach offers key advantages over existing methods as it enables rapid transient expression and can be applied to widely diverse hornwort species. [ABSTRACT FROM AUTHOR]

Knowledge integration based on the relationship between structure and function of the neural substrate is one of the main targets of neuroinformatics and data-driven computational modeling. However, the multiplicity of data sources, the diversity of benchmarks, the mixing of observables of different natures, and the necessity of a long-term, systematic approach make such a task challenging. Here we present a first snapshot of a long-term integrative modeling program designed to address this issue in the domain of the visual system: a comprehensive spiking model of cat primary visual cortex. The presented model satisfies an extensive range of anatomical, statistical and functional constraints under a wide range of visual input statistics. In the presence of physiological levels of tonic stochastic bombardment by spontaneous thalamic activity, the modeled cortical reverberations self-generate a sparse asynchronous ongoing activity that quantitatively matches a range of experimentally measured statistics. When integrating feed-forward drive elicited by a high diversity of visual contexts, the simulated network produces a realistic, quantitatively accurate interplay between visually evoked excitatory and inhibitory conductances; contrast-invariant orientation-tuning width; center surround interactions; and stimulus-dependent changes in the precision of the neural code. This integrative model offers insights into how the studied properties interact, contributing to a better understanding of visual cortical dynamics. It provides a basis for future development towards a comprehensive model of low-level perception. Author summary: Computational modeling can integrate fragments of understanding generated by experimental neuroscience. However, most models considered only a few features of neural computation at a time, leading to either poorly constrained models with many parameters, or lack of expressiveness in over-simplified models. A solution is to develop detailed models, but constrain them with a broad range of anatomical and functional data to prevent overfitting. This requires a long-term systematic approach. Here we present a first snapshot of such an integrative program: a large-scale spiking model of cat primary visual cortex, that is constrained by an extensive range of anatomical and functional features. Together with the associated modeling infrastructure, this study lays the groundwork for a broad integrative modeling program seeking an in-depth understanding of vision. [ABSTRACT FROM AUTHOR]

Despite the bombardment of AI ethics frameworks (AIEFs) published in the last decade, it is unclear which of the many have been adopted in the industry. What is more, the sheer volume of AIEFs without a clear demonstration of their effectiveness makes it difficult for businesses to select which framework they should adopt. As a first step toward addressing this problem, we employed four different existing frameworks to assess AI ethics concerns of a real-world AI system. We compared the experience of applying the AIEFs from the perspective of (a) a third-party auditor conducting an AI ethics risk assessment for the company, and (b) the company receiving the audit outcomes. Our results suggest that the feel-good factor of doing an assessment is common across the AIEFs that can take anywhere between 1.5 and 20 h to complete. However, each framework provides different benefits (e.g., issue discovery vs. issue monitoring) and is likely best used in conjunction with one another at different stages of an AI development process. As such, we call on the AI ethics community to better specify the suitability and expected benefits of existing frameworks to enable better adoption of AI ethics practice in the industry. [ABSTRACT FROM AUTHOR]

Copyright of Law & Justice Review is the property of Justice Academy of Turkey and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nanostructure formation on Co(110) surfaces was studied by using irradiation with cluster ion beams with oblique incidence and an energy of 250 eV/atom. In this work, the effect of the mass of the cluster projectiles on the process was analyzed. The launched clusters were formed by different types of charged atoms: He, Ne, Ar, Kr, and Xe. Due to the different collision processes, the formed surface patterns stand out more if the mass of the projectile atoms is greater, regardless of the angle of incidence of the clusters. Two processes control the morphological evolution of the surface during the bombardment phase: sputtering erosion and surface atomic redistribution. At grazing angles, the contribution of sputtering is greater during the process. In fact, heavier species give greater sputtering, and the redistribution factor becomes lower. The weight of redistribution is greater for intermediate angles above the critical angle (50° and 60°), since the displacement is greater for heavier species, and the redistribution factor takes substantially higher values. The experimental results point to a shift in the critical angle with the mass of the projectile atom. In the case of He, a very light ion, the results are marked by channeling and vertical displacements. [ABSTRACT FROM AUTHOR]

This article aims to make sense of My Son Hunter (The Unreported Story Society and Breitbart News, 2022; dir. Robert Davi). The first part of the analysis discusses My Son Hunter as an example of right-wing counter-cinema that tries to simultaneously tap into the cultural prestige associated with feature filmmaking and provide niche audiences with "paracinematic" pleasures. The second part of the analysis explores cinematic form and filmmaking techniques in My Son Hunter, demonstrating how the movie extends a promise of "truth" via an affective bombardment that draws on melodrama and paranoid fiction, as well as the flexible modes of docudramatic approximation. The overall effect is to make logic and argumentation superfluous, which is indicative of how the film can be regarded as both symptomatic and productive of a "post-truth" condition. [ABSTRACT FROM AUTHOR]

Most impact basins are believed to have formed during the early epochs of planetary evolution. The planet's gravity, internal structure, and thermal regime have the strongest control over their formation. Because of this, we can use the geophysical constraints on Mars' interior composition, structure, and geophysical evolution derived from the InSight mission to better understand the formation of impact basins on the planet. To achieve this, we performed numerical simulations of large impacts using the iSALE shock physics code. We investigated the effects of temperature and crustal thickness variations on impact basin size and morphology. Our scaling relationships indicate that: (a) basins formed in a warmer crust have larger final diameters in comparison to basins formed in a colder crust, a difference that is further accentuated as basin size gets bigger; and (b) the largest impact basins on Mars were created by impactors ranging from 35 to 680 km in diameter, up to ∼32% larger than estimates based on classical scaling. Our results expand the current understanding of the extent of early and large impact bombardment on Mars and provide a more comprehensive knowledge of impact basin formation on planetary surfaces. Plain Language Summary: The recent advancements in the understanding of Mars' that resulted from the InSight mission can be used to better understand the early large bombardment that took place 4.4 to 3.7 Ga ago. This bombardment formed impact basins, the largest and most complex type of craters. Their size and shape depend on the interior structure and temperature of the planet when they formed. We can better understand basins by simulating their formation and comparing the results with observations. Here, we used advanced interior structure and temperature evolution models of Mars to simulate the formation of impact basins as accurately as possible. We simulated basins of various sizes forming at different locations at multiple stages during Mars' evolution. Based on that, we derived equations referred to as scaling relationships that express the connection between basin size and impact conditions for different epochs and locations on Mars. We concluded that: (a) basins formed in a warmer crust are larger than basins formed in a colder crust, and (b) the largest reported basins on the planet were created by impactors much larger than previously thought. Our results provide a more comprehensive knowledge of impact basin formation and valuable insights into the early large bombardment. Key Points: We numerically simulated impact basin formation on Mars using recent internal structure and temperature modelsWe described how thermal evolution and crustal thickness variations could have affected impact basin formation on MarsWe derived new scaling relationships for impact basins and provided an insight into the early large bombardment on Mars [ABSTRACT FROM AUTHOR]

The standard image of First World War soldiers is of men in open trenches: waiting to attack or be attacked; walking, sitting, sleeping, dead. Ford's Parade's End includes such scenes. But it is a different kind of image which predominates in his war writings and often produces its most memorable passages: images of houses or house-like shelters. The mind seeks protection in such structures; but they offer little security against the destructiveness outside, against the bombardments, gas, shrapnel, bullets. Ford wrote that the experience of war revealed: 'men's dwellings were thin shells that could be crushed as walnuts are crushed. ... all things that lived and moved and had volition and life might at any moment be resolved into a scarlet viscosity seeping into the earth of torn fields [...]'. This realisation works in two ways. The soldier's sense of vulnerability provokes fantasies of home, solidity, sanctuary, while for the returnee soldier, domestic architecture summons war-visions of its own annihilation: 'it had been revealed to you', adds Ford, 'that beneath Ordered Life itself was stretched, the merest film with, beneath it, the abysses of Chaos'. It is now customary to read war literature through trauma theory. Building on analyses of Ford's use of repression, but drawing instead on object relations theory, I argue that Ford's houses of war are not screen memories but images of the failure of repression to screen off devastating experiences. The abysses of Chaos can be seen through the screen or projected upon it. Attending to Ford's handling of this theme enables a new reading of his war writing and a new case for its coherence. The essay will connect the opening of No More Parades (in a hut, during a bombardment) with the war poem 'The Old Houses of Flanders'; the postwar poem A House; the memoir It Was the Nightingale (quoted above); and the otherwise puzzling, fictionalised memoir No Enemy, structured in terms of 'Four Landscapes' and 'Certain Interiors'. [ABSTRACT FROM AUTHOR]

The exfoliation and uniform dispersion of two-dimensional nanofillers are significantly important to improve the comprehensive properties of silicone rubber including the tracking resistance and mechanical properties. Herein, tetrabutylammonium hydroxide-intercalated zirconium phosphate (M-ZrP) and urethane-containing silane (US) were incorporated into addition-cure liquid silicone rubber (ALSR). The interaction between US and M-ZrP and the dispersion of M-ZrP in ALSR were investigated. It was found that US contributed to the exfoliation and dispersion of M-ZrP in ALSR. M-ZrP and US synergistically improved the tracking resistance of ALSR. ALSR/US/M-ZrP containing 0.1 phr M-ZrP and 1.0 phr US classed 1A4.5 level, and the ratio of electrical eroded mass was only 0.11%. The effect of M-ZrP and US on the thermal degradation behavior of ALSR and the electrical erosion residue after inclined plane test were systematically studied. It was revealed that US and Karstedt's catalyst (Pt) synergistically promoted silicone rubber to form ceramic layer under strong arc bombardment. Besides, the exfoliated M-ZrP nanosheets in ALSR served as barrier layer and support skeleton. When subjected to arc bombardment, a compact ceramic barrier formed on the ALSR/US/M-ZrP surface, which protected the internal matrix, thus significantly improved the tracking resistance of ALSR. [ABSTRACT FROM AUTHOR]

Background: The low efficiency of genetic transformation in Chinese cabbage (Brassica rapa L. ssp. pekinensis) is the key problem affecting functional verification. Particle bombardment is a widely used method along with the Agrobacterium-mediated method. As a physical means, it has almost no restrictions on the type of host and a wide range of receptor types, which largely avoids the restriction of explants. The bombardment parameters, which include the number of bombardments, the bombardment pressure, and the bombardment distance, may affect the microspores' genetic transformation efficiency. Results: The transformation efficiency was improved using the particle bombardment method under the combination of bombardment shot times (3, 4, 5) × bombardment pressure (900, 1100, 1350 psi) × bombardment distance (3, 6, 9 cm). The average viability of microspores in the treatment group ranged from 74.76 to 88.55%, while the control group was 88.09%. When the number of shot times was 4, the number of embryos incubated in the treatment group ranged from 16 to 236 per dish, and the control group had 117 embryos per dish. When the bombardment parameters of the biolistic method were 4 shot times—1350 psi—3 cm, 4 times—1100 psi—3 cm, and 4 times—900 psi—3 cm, they had high transient expression efficiency, and the average number of transformed microspores was 21.67, 11.67, and 11.67 per dish (3.5 mL), respectively. When the bombardment parameters were 4 times, 900 psi, and 6 cm, the highest genetically transformed embryos were obtained, and the transformation efficiency reached 10.82%. Conclusion: A new genetic transformation system with proper parameters for Chinese cabbage microspores was established using particle bombardment. This proper transformation system could provide a useful tool for the improvement of cultivar quality and the investigation of functional genes in Chinese cabbage. [ABSTRACT FROM AUTHOR]

Cold traps are locations on the Moon that are shielded from sunlight where volatiles such as water could accumulate and persist against sublimation for geologic timescales. We model how long it takes accumulating craters to produce and then obliterate sub‐kilometer scale cold traps. Sub‐meter cold traps are extremely ephemeral, evolving in and out of existence over less than a few thousand years; however, larger 100 m to 1 km‐scale cold traps may persevere for geologic timescales and preserve a record of the volatile history of the Moon. Plain Language Summary: Volatiles like water may exist in the shadows at the bottom of craters near the poles of the Moon; however, the Moon is subjected to intense bombardment by high‐velocity meteorites, and the subsequent bombardment by the rocks meteorite impacts kick up. Crater‐forming bombardment controls both the production and destruction of craters where volatiles may be safe. Using knowledge of the intensity of bombardment, we model how long volatile‐harboring cold traps last on the Moon and find that small cold traps (<10 m) are extremely ephemeral, while large cold traps (>100 m) could last for geologic time. Key Points: Lunar micro cold traps are extremely ephemeral (<1 m scale last only thousands of years)Volatiles discovered within micro cold traps will have been transported there recentlyLarge cold traps are exponentially more durable than small cold traps and may harbor ancient volatiles [ABSTRACT FROM AUTHOR]

This article is the result of a set of investigations performed in Tunis over a period of two years. The scope of this article is to better investigate a series of events that happened in Aïn Draham on May 31st 1957, by proposing the accurate description that is largely missing in the existing literature. The aim is to devote a broader space to those events by placing them in the context of the post-independence period, as well as in Habib Bourguiba's (al-Ḥabīb Būrqība) actions, by trying to demonstrate the existence of a link between Aïn Draham clashes and overstudied events such as Sakiet Sidi Youssef and the Bizerte war. The ultimate goal is to challenge current literature's approach, which moves directly from the independence (1956) to the Bizerte evacuation (1961), having as the only intermediate event the bombardment of Sakiet Sidi Youssef in 1958. Aïn Draham battle occurred during a crucial and delicate period of Tunisian history, as a result of internal and external tensions, in an area under extreme pressure (the Algerian–Tunisian border) and on the edge of an international crisis. The main idea behind the article is to re-evaluate resistance pathways and understand the value of understudied histories, as well as their contribution to and influence over well-known events of Tunisian contemporary history. [ABSTRACT FROM AUTHOR]

The 'disparitas conjecture' states that unicellular life is common in the galaxy but that multicellular life is rare in comparison. A variation of this conjecture is that unicellular life may be common in the galaxy but that intelligent life is rare. However, microbial life can and does indeed display characteristics of intelligence. Thus, in this work, how life could have potentially endured through the Late Heavy Bombardment (LHB) through intelligent strategies such as decision-making, association and anticipation, communication and self-awareness was investigated. At the LHB, there would have been, for microbial life, an unpredictable environmental fluctuation regarding pools of amino acids, lipids and fluids available when impacts and reimpacts launched organisms into new habitats. Thus, evolutionary strategies must have been favoured that could stretch the available external and internal resources as long and as efficiently as possible. Thus, inclusive fitness or kin altruism could have emerged, where organisms adapt to acquire energy and nutrients from siblings who voluntarily autolysed to replenish the amino acid pool for their kin. A further strategy could also evolve where members of the same species can recognize each other and actively isolate themselves from other species, which allows them to better utilize the amino acid pool. Thus, the organisms will potentially be able to survive for a long time in this manner until new impacts launch them to new spots with amino acid pools. There has thus been an alternating increase and decrease in the number of organisms during this localized planetary reseeding, and life may have endured this way until the bombardments were over. Thus, if a world inhabited only by analogous bacteria, archaea and protists is located elsewhere in the galaxy, the existence of intelligent life there cannot be excluded. [ABSTRACT FROM AUTHOR]

In the presented article, samples were studied using Auger electron spectroscopy, recording the angular dependences of the coefficient of elastically reflected electrons η, and spectroscopy of elastically reflected electrons. A change in the composition and degree of disorder of the surface layers of Si (111) was detected when bombarded with Ar+ and K+ ions with a change in energy E0 ∼ from 1 to 10 keV and ion dose from ∼ 1013 to 1017 cm−2. It was found that although the Ar and K atoms have the same masses, at the same ion energies, the degree of disordering of the near-surface Si(111) layer differs significantly. The observed effect is explained by the significant difference in their ionic radii. It is shown that at E0 ≥ 3 keV, the complete amorphization of near-surface layers occurs at relatively lower doses than surface amorphization.

The deuteron is a loosely bound system that can easily break up into its constituent proton and neutron whilst in the presence of Coulomb and nuclear fields. Previous experimental studies have shown that this breakup process has a significant impact on residual-nucleus production from deuteron bombardment in the high-energy range of 50–210 MeV/nucleon. However, there remains a lack of cross-section data at energies below 50 MeV/nucleon. The current study determined 93Zr + d reaction cross sections under inverse kinematics at approximately 28 MeV/nucleon using the BigRIPS separator, OEDO beamline, and SHARAQ spectrometer. Cross sections from this research were compared with previous measurements and theoretical calculations. The experimental results show a large enhancement of the production cross sections of residual nuclei, especially those produced from a small number of particle emissions, compared to the proton-induced reaction data at similar bombarding energy. The DEURACS calculation, which quantitatively takes deuteron-breakup effects into account, reproduces the data well. As a long-lived fission product, 93Zr remains a challenge for nuclear-waste disposal and treatment. This study's low-energy data may assist future consideration of nuclear-waste treatment facilities, where 93Zr + d may feasibly transmute the waste into short-lived/stable nuclei. [ABSTRACT FROM AUTHOR]

The thermal history of asteroids is recorded by the radioisotopic ages of meteorites that derive from them. Radioisotopic ages may date a number of events, such as the cooling of a parent body during waning radiogenic metamorphism, rapid cooling experienced upon parent body break-up, and/or subsequent collision-induced reheating of material. However, sampling statistics for meteorite radioisotope ages are currently relatively low and most are derived from analyses of bulk material, therefore lacking the in-situ microtextural context that aids in distinguishing collisional events. Here, we present new in-situ apatite U-Pb ages for nine L chondrite meteorites using secondary ionisation mass spectrometry. Our measurements greatly expand the L chondrite phosphate U-Pb age record and provide evidence for distinct stages in the thermal evolution of the L chondrite parent asteroid, including: early collisions driving parent body fragmentation- and/or exhumation-associated cooling at >4530 Ma; onion-shell-style cooling with waning radiogenic metamorphism until 4500 Ma; late collisional reheating from 4480–4460 Ma; parent body break-up at 474 ± 22 Ma; and recent ejection events within several 10s of Myr of present day. We show that meteorite shock stage correlates with upper intercept age but is uncorrelated with lower intercept age. This outcome links the upper intercept ages alone to the preserved high-energy impact-related features in strongly shocked meteorites, which has important implications for our interpretation of the L chondrite U-Pb record. We see no evidence in our record for collisional episodes between 3000–4400 Ma, i.e., the Late Heavy Bombardment. Our upper intercept age record hints that collision rates changed as a result of some dynamical instability at 4460–4480 Ma, which may have strongly depleted the main asteroid belt, and/or that L asteroid physical structure changed such that the shock metamorphic response to collisions was muted after this time, e.g., by the formation of weak rubble pile bodies. L chondrite phosphate U-Pb ages provide evidence for a heterogeneous early and shared late (less than 500 Ma) thermal history for the majority of L chondrite meteorites falling to Earth today. From this observation, we infer that most L chondrites derive from a single parent asteroid (in existence from around 4500–4440 Ma to 474 ± 22 Ma), which has since been disturbed to create an asteroid family. Our record of meteorite U-Pb ages traces out the thermal and dynamical evolution of the L chondrite asteroid. These observations can be used in future to benchmark dynamical models of Solar System evolution. [ABSTRACT FROM AUTHOR]

Al-Minbar newspaper covered a wide range of topics in its pages from its inception to its latest issue. Politics, society, and culture received the most significant coverage. The newspaper also addressed a vital and crucial topic, which is the results of the Second Gulf War. It published numerous articles and studies about the outcomes of the war, presenting a comprehensive study that included the decisions of the United Nations Security Council against Iraq. Additionally, the newspaper discussed the injuries suffered by the international coalition forces from diseases and epidemics due to the use of deadly chemical weapons in their military operations, especially targeting those weapons stored in Iraq. This resulted in a large number of citizens being afflicted with cancerous and dermatological diseases, as well as birth defects among newborns. [ABSTRACT FROM AUTHOR]

Michael Reeve's book, "Bombardment, Public Safety and Resilience in English Coastal Communities during the First World War," offers a fresh perspective on the war by focusing on the experiences of coastal towns in the North-East of England. Reeve argues that understanding the experiences of people living in these areas is crucial for contextualizing wider war narratives, which often focus on the metropolitan experience. The book explores how local and national governance interacted with civilian ideas of liberty, particularly in relation to early warning systems and shelters. It also examines the impact of living in a coastal town on individuals, including the emotional toll and the effects on the public psyche. Overall, Reeve's work suggests new avenues for research into British experiences of war and highlights the importance of local studies in understanding the war's impact on different parts of the UK. [Extracted from the article]

Within the cold regions of space, ices that are enriched with carbon monoxide (CO) molecules are exposed to ionizing radiation, which triggers new reactions and desorption processes. Laboratory studies on astrochemical ices employing different projectiles have revealed the appearance of several new species. In this study, we employed the upgraded PROCODA code, which involves a calculation phase utilizing thermochemistry data, to map the chemical evolution of pure CO ice irradiated by cosmic-ray analogs. In the model, we have considered 18 different chemical species (six observed: CO, CO2, C3, O3, C2O, and C5O3; 12 unobserved: C, O, C2, O2, CO3, C3O, C4O, C5O, C2O2, C2O3, C3O2, and C4O2) coupled at 156 reaction routes. Our best-fit model provides effective reaction rates (effective rate constants, (ERCs)), branching ratios for reactions within reaction groups, several desorption parameters, and the characterization of molecular abundances at the chemical equilibrium (CE) phase. The most abundant species within the ice at the CE phase were atomic oxygen (68.2%) and atomic carbon (18.2%), followed by CO (11.8%) and CO2 (1.6%). The averaged modeled desorption yield and rate were 1.3e5 molecules ion−1 and 7.4e13 molecules s−1, respectively, while the average value of ERCs in the radiation-induced dissociation reactions was 2.4e-1 s−1 and for the bimolecular reactions it was 4.4e-24 cm3 molecule−1 s−1. We believe that the current kinetics study can be used in future astrochemical models to better understand the chemical evolution of embedded species within astrophysical ices under the presence of an ionizing radiation field. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Babylon Center for Humanities Studies is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of irradiation with low-energy oxygen ions on the composition and some properties of the layer formed on the thallium surface has been studied. It is shown that bombardment with oxygen ions leads to the formation of a two-dimensional oxide layer, which effectively passivates the surface. [ABSTRACT FROM AUTHOR]

Unheard-of luck. Lost and rediscovered finds from the princely graves at Lübsow (Lubieszewo, pow. Gryfice, woj. zachodniopomorskie, PL) Between 1942 and 1944, the most valuable parts of the collection of the Pommersches Landesmuseum in Stettin were evacuated to selected sites for fear of bombardment and the loss of cultural property, and left in the care of trusted persons, mainly representatives of well-known Pomeranian landowners. One of these removal sites was the Moltow estate (today Mołtowo). The finds evacuated to the property Moltow had been removed from the manor house under unknown circumstances between the late 1940s and early 1970s. They prove that after the end of the war they were preserved in good condition for at least a few years in the place where have been deposited before 1945, and that they were probably scattered and partly destroyed in the following years. In 2016, finds bearing inventory numbers of the former Pommersches Landesmuseum were discovered by chance in Mołtowo (the former Moltow) in the area of a former sand pit used as a rubbish dump. They were professionally recovered by employees of the Muzeum Narodowe Szczecin and the Museum of Polish Weaponry in Kołobrzeg. This collection also include finds from three Early Roman Iron Age princely graves at Lübsow (Lubieszewo). They are presented and described here as a supplement to the monograph on the graves of Lübsow published in 2010. [ABSTRACT FROM AUTHOR]

Polish border guards can't stop a few dozen fast-wheeled APCs and IFVs. If such a force would cross through any road at the eastern border of Poland, it would pass almost intact. Afterward, it would be an easy target, but only before it could hide in a dense urban area. Is eastern Poland prepared for such a surprise attack of under a hundred vehicles that could arrive in many city centres within an hour after the border crossing? If a Russian force arrives at even a medium-sized city centre, they could occupy and hold such a position for weeks and use local civilians as human shields. They could force political negotiations holding also precious city infrastructure hostage. Lack of fast and decisive decision-making which is highly likely (because any bombardment will mean a loss of life of civilians) will only make any attempt to regain the city more difficult. [ABSTRACT FROM AUTHOR]

Theranostic matched pairs of radionuclides have aroused interest during the last couple of years, and in that sense, copper is one element that has a lot to offer, and although 61Cu and 64Cu are slowly being established as diagnostic radionuclides for PET, the availability of the therapeutic counterpart 67Cu plays a key role for further radiopharmaceutical development in the future. Until now, the 67Cu shortage has not been solved; however, different production routes are being explored. This project aims at the production of no-carrier-added 67Cu with high radionuclidic purity with a medical 30MeV compact cyclotron via the 70Zn(p,α)67Cu reaction. With this purpose, proton irradiation of electrodeposited 70Zn targets was performed followed by two-step radiochemical separation based on solid-phase extraction. Activities of up to 600MBq 67Cu at end of bombardment, with radionuclidic purities over 99.5% and apparent molar activities of up to 80MBq/nmol, were quantified. [ABSTRACT FROM AUTHOR]

Here, we present calculations on the energy delivered (and heating) by realistic cosmic rays (CRs) field at a typical molecular clump. The current model describes, with unprecedented spatial resolution, the energy delivery by a realistic CR field in molecular clumps. The calculations were performed employing the Geant4 code (considering full cascade physical processes and hadron physics) considering the cosmic ray field taken from the Voyager spacecraft measurements in the interstellar medium. The results showed that the total energy deposition rate, considering light particles (protons, electrons and alphas), medium-mass ions and heavy-ions, ranges from 400 MeV/g/s in the outer layer (at 105 AU) to roughly 100 MeV/g/s in the inner layer of the model (below 0.1 AU). The main energy deposition rate is due to the incoming protons. Incoming alphas represent 15–20 per cent of the energy deposition. In the deep core of the cloud, the fraction of energy delivered by medium-mass ions, electrons, and heavy ions are 5 per cent, 2.5 per cent, and 1 per cent, respectively. The heating induced by cosmic rays seems to affect mostly the regions above ∼500 AU. Considering a balanced heat model with warm dust grains (T∼16–18 K), we observe a small bump in temperature at 2000–5000 AU. We suggest this temperature enhancement by CRs might have some affect on the molecular formation or cometary formation in pristine Oort cloud region inside the Solar System. [ABSTRACT FROM AUTHOR]

In this work, negative-ion production on the surface of a sample negatively DC biased in a hydrogen plasma is studied. The negative ions created under positive ion bombardment are accelerated toward the plasma, self-extracted, and detected according to their energy and mass, by a mass spectrometer placed in front of the sample. The use of a pulsed bias allows applying a quasi-DC bias on insulating material during a short period of time and offers the possibility to extend the measurement method to nonconductive samples. The pulsed-bias tests were performed first with highly oriented pyrolytic graphite (HOPG), a conductive material, to demonstrate the feasibility of the method. By changing the pulsed-bias frequency, it was possible to obtain HOPG material with different hydrogen surface coverages and hence different surface states leading to an increase of negative-ion production by up to 30%–50% as compared to the continuous bias case. To establish a protocol for insulating materials, charge accumulation on the surface during the bias pulse and influence of the bias duration and frequency were explored using microcrystalline diamond (MCD) thin layers. By using a pulse short enough (10 μs) at 1 kHz frequency, it has been possible to measure negative-ions on the MCD sample at a quasi-constant surface bias of 130 V, with only 1 V variation during the measurement. Negative-ion surface production on MCD has been studied in pulsed mode with surface temperature from room temperature to 800 °C. It is shown that pulsing the bias and increasing the temperature allows limiting defect creation on MCD which is favorable for negative-ion production. Consequently, at 400 °C, the yield on MCD in pulsed mode is one order of magnitude higher than the yield on HOPG in continuous mode at room temperature. [ABSTRACT FROM AUTHOR]

The aim of this work is the study of the argon implantation on the corrosion resistance behavior of AISI 304 stainless steel substrates. The effect of ion implantation dose on morphology and corrosion properties of AISI 304 SS has been investigated. In this work, argon ions of 30 keV energy have been implanted into AISI 304 stainless steel at different fluences ranging from 3 × 1017to 10 × 1017Ar/cm².The AFM analysis of implanted samples clearly shows significant change in surface. In order to evaluate the effect of the ion bombardment on the corrosion behavior, otentiodynamic tests were performed. The results show that the corrosion resistance of the samples strongly depends on the implantation fluences. The Corrosion potential and roughness curves obviously indicate that corrosion Potential variations caused by argon ion bombardment are inversely proportional to surface roughness. Corrosion current variations show an optimal dose at 5 × 1017ions/ cm² in which the corrosion resistivity is 12 times higher than unimplanted sample. [ABSTRACT FROM AUTHOR]

• Hyperthermal erosion of knitted graphene nanoribbon sheet (KGS) is investigated. • KGS holds better anti-hyperthermal erosion performance than monolayer graphene. • Porosity significantly affects erosion and mechanical properties of 2D / 2.5D KGS. With outstanding thermal, mechanical, and chemical properties, graphene has been proposed as a promising heat shield material for hypersonic applications. Knitted graphene composites have shown further improved properties, whose behavior under highly non-equilibrium hyperthermal conditions, however, is still unknown. This work investigates the hyperthermal erosion and mechanical behaviors of 2D and 2.5D knitted graphene-nanoribbon sheet (KGS) under hyperthermal atomic oxygen impact conditions using the Reactive Molecular Dynamics (RMD) method. The simultaneous analysis of the morphology evolution and gaseous products demonstrate that knitted structures possess improved anti-erosion and mechanical properties than those of the plain graphene, and the 2.5D knitted graphene structure shows better performance than those of 2D knitted ones. 2D structure porosity, ribbon aspect ratio, and 2.5D knitting volumetric porosity show significant influence on the hyperthermal erosion of materials under atomic oxygen bombardment, which suggests strategies for future optimization of knitted graphene properties. [ABSTRACT FROM AUTHOR]

Crop improvement faces a lot of challenges ranging from genetic effects of seeds to environmental factors, among others. Therefore, certified hybrid seeds of maize (Oba super II), were exposed to three different doses of X-ray radiation: 3 MGy, 6 MGy, 9 MGy and a control, no exposure (0 MGy) to assess the effect of irradiation on growth performance, grain yield and nutritional status of maize. The field research was conducted in 2016 cropping season at Michael Okpara University of Agriculture, Umudike (latitude 05° 29'N; longitude 07° 33'E; altitude 122 masl), southeast Nigeria. The experiment was laid down in a randomized complete block design with three replications. The results indicated that X-ray irradiation significantly affected growth, yield and nutritional status of maize. The application of 6 MGy of X-ray dose gave the longest cob, highest 100-seed weight and grain yield (4,973.00 kg ha-1) as well as nutritional values of the crop such as β-carotene, vitamin C, protein and phosphorus relative to the other treatments suggesting a possible genetic synergy from the dosage level. Correlation showed that above ground dry matter, crop growth rate and absolute growth rate had positive and significant (P≤0.05) relationships with grain yield. The mean sequence of grain yield obtained from maize due to X-ray bombardment of the seeds before planting was in the order: 6 MGy X-ray irradiation>9 MGy X-ray irradiation>3 MGy X-ray irradiation>0 MGy X-ray irradiation. The implications of these results can lead to further improvement of maize varieties in southeast Nigeria. [ABSTRACT FROM AUTHOR]