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In this work, the heterodimeric phospholipase A2, HDP-2, from viper venom was investigated for its hydrolytic activity in model myelin membranes as well as for its effects on intermembrane exchange of phospholipids (studied by phosphorescence quenching) and on phospholipid polymorphism (studied by 1H-NMR spectroscopy) to understand the role of sphingomyelin (SM) in the demyelination of nerve fibers. By using well-validated in vitro approaches, we show that the presence of SM in model myelin membranes leads to a significant inhibition of the hydrolytic activity of HDP-2, decreased intermembrane phospholipid exchange, and reduced phospholipid polymorphism. Using AutoDock software, we show that the NHδ+ group of the sphingosine backbone of SM binds to Tyr22(C=Opbδ–) of HDP-2 via a hydrogen bond which keeps only the polar head of SM inside the HDP-2's active center and positions the sn-2 acyl ester bond away from the active center, thus making it unlikely to hydrolyze the alkyl chains at the sn-2 position. This observation strongly suggests that SM inhibits the catalytic activity of HDP-2 by blocking access to other phospholipids to the active center of the enzyme. Should this observation be verified in further studies, it would offer a tantalizing opportunity for developing effective pharmaceuticals to stop the demyelination of nerve fibers by aberrant PLA2s with overt activity – as observed in brain degenerative diseases – by inhibiting SM hydrolysis and/or facilitating SM synthesis in the myelin sheath membrane. Binding of sphingomyelin (SM) to catalytic subunits of HDP-2 predicted by Autodock. SM is given in sticks representation and HDP-2P is displayed in molecular surface (A) and line stick representation (B). For the stick diagrams, emerald represents carbon, blue–nitrogen, orange–phosphorus, red–oxygen, white–hydrogen. For molecular surface and lines, green represents carbon, blue–nitrogen, red–oxygen, white–hydrogen, yellow–sulfur. Yellow broken lines identify intermolecular bonds. Arrows point to sn-2 bonds. Hydrogen bond between NHδ+ group and Tyr22(C=Opbδ–) and ionic bond between PO4– group and His48 drive the positioning of the sn-2 acyl ester bond away from the active center that suggests that SM binds non-productively in the active center of HDP-2 enzyme. [ABSTRACT FROM AUTHOR]

The article published in the Journal of Neurological Surgery focuses on the microanatomy of the temporal division of the facial nerve in the periorbital region, specifically for minimally invasive keyhole approaches (MIKA) to the anterior skull base and circle of Willis. The study aims to define a safe zone for skin incisions during MIKA by identifying reliable skin landmarks to avoid the branches of the temporal division of the facial nerve. Through cadaveric dissections, the researchers found a semicircular area around the lateral canthus with a low chance of containing a temporal division branch, providing a clinically applicable landmark for surgical planning in the superolateral region of the orbit. [Extracted from the article]

The correction notice in the Molecular Brain journal addresses errors in Figures 4, 6, and 8 of the original article regarding Rufy3's role in subarachnoid hemorrhage-induced brain injury. The errors were related to the amplification area in specific groups and the description of β-tubulin III. The corrections made do not impact the study's results or conclusions. The authors have provided updated and accurate figures for reference. [Extracted from the article]

Whether small number magnitudes are inherently represented as lying to the left of larger ones, the space–number association (SNA), is an important issue in mathematical cognition. In this fMRI study, we used a go/no-go implicit association task to investigate the brain activity and functional connectivity underlying the SNA. Arabic digits lower or higher than 5 and left- or right-pointing arrows were alternated as central targets. In a single-code task condition, participants responded to a specific number magnitude and to all arrows or to a specific arrow direction and to all number magnitudes. In a joint-code (JC) condition, responses were provided after congruent, for example, "go when a number is lower than 5 or an arrow points left," or incongruent, for example, "go when a number is lower than 5 or an arrow points right," SNAs. The SNA was only found in the JC condition, where responses were faster with congruent instructions. Analyses of fMRI functional connectivity showed that the SNA was matched with enhanced excitatory inputs from ACC, the left TPJ, and the left inferior frontal gyrus to the left and right intraparietal sulcus (IPS). Incongruent JC trials were associated with enhanced excitatory modulation from ACC to the left and right IPS. These results show that the SNA is associated with enhanced activation of top–down brain control and changes in the functional interaction between the left and right IPS. We conclude that the SNA does not depend on an inherent and bottom–up spatial coding of number magnitudes. [ABSTRACT FROM AUTHOR]

This research explores the use of Double Arrowhead (DAH) structures, known for their light weight, high compressive stiffness, and energy absorption. A novel truss-supported DAH structure with a circular node was investigated under compression loads. Samples were fabricated using FDM additive manufacturing with both reinforced and non-reinforced PLA filaments. The truss supported DAH structure with a circular node, made from Carbon Fiber reinforced PLA, demonstrated superior performance with a compression strength of 19.3780 MPa, a strength to weight ratio of 0.3561 MPa/g, and a total specific energy absorption of 13903.3367 J/kg. [ABSTRACT FROM AUTHOR]

Combining reentrant honeycomb (RH) and double arrowhead honeycomb (DAH), the reentrant double arrowhead honeycomb (RDAH) is proposed. The deformation modes and compression behavior of the RDAH are numerically simulated and compared with the RH. The results show that the RDAH has a better specific energy absorption SEA than the RH regardless of low velocity or high velocity impact. Compared with the RH, the SEA of the RDAH increased by 9.4% under an impact velocity of 1 m/s and increased by 24.4% under an impact velocity of 100 m/s. The mechanical properties of the RDAH under different impact velocities and relative densities were further discussed, and empirical formulas were established based on the deformation mode map to predict the dynamic bearing capacity of the RDAH. Finally, the influence of the cell number on the in-plane compression of the RDAH is discussed, and it is found that an RDAH larger than 4 × 4 can produce more stable deformation. The influence of different cell vertical ligament heights h and relative densities ρ * on the mechanical properties of the RDAH is researched parametrically. The increase in the unit vertical ligament height h will reduce the SEA and destroy the stable deformation of the RDAH. SEA increases almost linearly with increasing relative density. [ABSTRACT FROM AUTHOR]

The replacement of the atlatl and dart weapon system with the bow and arrow system in the Basin-Plateau region was a significant technological event. Distinguishing dart points from arrow points is one component of understanding the timing of this event. Previous analyses demonstrated that size differences of shoulder widths distinguish dart from arrow points. However, neck width and thickness of a stone projectile point are better variables for differentiating arrow points from dart points because these variables directly relate to the attachment of a projectile point to a foreshaft or mainshaft. Because of overlaps in foreshaft diameters, projectile point neck widths, and thicknesses between darts and arrows, it is not always possible to separate projectile points into arrow points and dart points. In such cases, it is only possible to provide a probability estimate of correct classification for any individual specimen falling within the overlapping ranges. [ABSTRACT FROM AUTHOR]

Error monitoring is essential for detecting errors and may facilitate behavioral adjustments that can reduce or prevent future errors. At times, error monitoring must occur while individuals are engaged in other, cognitively demanding tasks that might consume processing resources necessary for error monitoring. Here, we set out to determine whether concurrent working memory (WM) load interferes with error monitoring, as measured using event‐related potentials, the error‐related negativity (Ne/ERN), and error positivity (Pe). Fifty‐four participants (n = 33 female) completed an arrowhead flanker task, with trials presented under low (2 letter) or high (6 letter) WM load. Participants were required to hold letter strings in memory and to recall these letters at the end of a set of flanker trials. Results showed that WM load reduced the Pe but did not affect the Ne/ERN. Therefore, WM load appeared to attenuate later, more elaborated stages of error processing, though initial error detection was unaffected. Additionally, high WM load slowed reaction times overall, but did not lead to a significant increase in errors. As such, slower responses may have helped participants maintain comparable accuracy for low‐load versus high‐load trials. Overall, results indicate that WM load interferes with the evaluation of error significance, which could interfere with behavioral adaptations over time. Error monitoring may rely on cognitive resources that are limited during cognitively demanding tasks. Using a modified flanker task interspersed with a working memory task, Frequentist and Bayesian analyses showed that greater working memory load reduced the error positivity, but not the error‐related negativity. Therefore, the elaborative processing of error significance may be compromised during a demanding cognitive task, though early error monitoring appears unaffected. [ABSTRACT FROM AUTHOR]

Armas de la tierra, mentioned in the muster roll for the Coronado expedition, have remained an enigma. Coronado expedition sites in southern Arizona have yielded considerable evidence to address this research issue at three locales. These newly defined unconventional metal point types are thought to be the southern equivalent of sheet and short block copper points found in New Mexico and Texas, where these southern types are absent, and all represent armas de la tierra. The frequency, condition, and spatial distribution of these points indicate that battles occurred at the 1539–1540 Chichilticale encampment and the 1541 San Geronimo III townsite at Suya. They co-occur with other diagnostic Coronado period artifacts, such as crossbow boltheads, stone arrowheads, copper bells, medieval horseshoes, gable-headed nails, lace aglets, and more. Their consistent occurrence and clustering make them another reliable index of the Coronado expedition and provide unexpected details about first contacts between Europeans and the Sobaipuri O'odham. [ABSTRACT FROM AUTHOR]

The horsemen, whose graves were discovered in the Prikubansky burial ground, represented the elite of the Maeotian army. Weapons were found in 28 burials. The main types of weapons were iron swords, spearheads, and arrowheads. Swords of the Sindo-Maeotian type were found in 26 burials, and in four burials there were two swords of different lengths. The swords differ in the blade width, the design of the transition space between the guard and the blade, and the shape of the bar-shaped pommel. Spearheads could be found in all the burials. Typically, a set consisted of 4–6 both heavy and light spearheads of various types. One dart tip was found among the spear tips in the three sets. Arrowheads were discovered in twenty burials. Sets of arrows consisted of various numbers of pieces, from a few to several dozens. Mostly, iron three-blade arrowheads were used (415 specimens), bronze (three-blade and triangular) were practically out of use (25 specimens), and bone bullet-shaped ones were represented by isolated finds. The arrows were placed in quivers, which were placed next to or under the sword. In the burials with two swords, there were two quivers. Specific types of weapons are long combat knives (30–42 cm) with bone handles found in seven burials. A set of combat knives could consist of 2–4 pieces. On the grounds of the position in the burial, it can be assumed that the knives were located in a special compartment of the quiver, in a case on the sheath of the sword, or in special wooden sheaths. The equipment of the horsemen included iron axes in the two burials. The dating of the equestrian assemblages is based on a narrow chronology of Greek amphorae from different centers of production, which are present in each burial. The high percentage of horseman complexes among the military burials of the Prikubansky necropolis is probably connected with the location of this group of the Maeotian population near the eastern border of the Asian Bosporus.

The correction notice in the Scientific Reports journal addresses errors in Figures 4 and 6 of an article on new species of Desmodesmus in Saga City, Japan. The corrected figures show scanning electron micrographs of different strains of Desmodesmus, highlighting unique characteristics of each species. The errors have been rectified in the original article by Mikihide Demura. [Extracted from the article]

We realize that a Sierpiński arrowhead curve (SAC) fills a Sierpiński gasket (SG) in the same manner as a Peano curve fills a square. Namely, in the limit of an infinite number of iterations, the fractal SAC remains self-avoiding, such that S A C ⊂ S G . Therefore, SAC differs from SG in the same sense as the self-avoiding Peano curve P C ⊂ 0,1 2 differs from the square. In particular, the SG has three-line segments constituting a regular triangle as its border, whereas the border of SAC has the structure of a totally disconnected fat Cantor set. Thus, in contrast to the SG, which has loops at all scales, the SAC is loopless. Consequently, although both patterns have the same similarity dimension D = ln ⁡ 3 / ln ⁡ 2 , their connectivity dimensions are different. Specifically, the connectivity dimension of the self-avoiding SAC is equal to its topological dimension d l S A C = d = 1 , whereas the connectivity dimension of the SG is equal to its similarity dimension, that is, d l S G = D . Therefore, the dynamic properties of SG and SAC are also different. Some other noteworthy features of the Sierpiński triangle are also highlighted. [ABSTRACT FROM AUTHOR]

Insufficient resources and high costs are hindering industrial development, potentially impeding adaptation to market demands. Overcoming this challenge necessitates advancements in software engineering techniques to streamline processes and meet industrial requirements. Crucially, automating manual tasks and enhancing interoperability between engineering stages can yield efficiency gains. This paper presents a model‐based system engineering approach aimed at automating the transition from design to implementation, incorporating autonomous generation and validation features. Implemented as plugins and utilizing model transformation techniques, this solution targets reducing engineering time and facilitating the adoption of new technologies. Developed, implemented, and tested within the Arrowhead framework, the approach is followed by a discussion on its benefits and limitations. [ABSTRACT FROM AUTHOR]

We examined the properties in orienting visual attention that are triggered by social cues (eye gaze or pointing finger) and nonsocial cues (an arrow). Particularly, we investigated whether the mental state of others would be modulated by any social cue. We presented an occluder between the cue and target to manipulate the mental state of an agent in cues (i.e., whether the agent is aware of the target). For Experiment 1, the reaction time (RT) to detect the target was prolonged when the target side was occluded only in the gaze‐cue condition, but not for the arrow or the pointing finger. For Experiment 2, the RT of a discrimination task, which demanded greater cognitive demand, was not prolonged for any cue type. These results suggest that the mental state attribution for the agency of the cue, which is affected by an occluder, is specific to the gaze cue, and suggest that it is under top‐down control that requires cognitive resources. [ABSTRACT FROM AUTHOR]

The article in the Pan-Pacific Entomologist discusses the re-discovery and detailed description of the gall of Andricus mendocinensis on the tanoak Notholithocarpus densiflorus. The gall was found in Northern California after extensive searches, and the study provides a comprehensive description of the gall's characteristics, location on the host plant, and its taxonomic affinities. The research also highlights the life history of the gall-inducing wasps and their interactions with the host plant. The study concludes that A. mendocinensis and A. notholithocarpi are closely related but distinct species, each inducing galls on the tanoak in a single generation. [Extracted from the article]

The invention or adoption of bows is one of the most significant global shifts in humanity's history, and tracking this in the archaeological record depends on metrically distinguishing dart and arrow projectile points. Given the importance of comparative databases in this endeavor, this paper presents an expanded compilation of measurements on 85 hafted points from North America. For South America, we present unpublished data for 22 hafted points and 61 foreshafts. A clear metric gap in point width at 14–15 mm separates arrows and darts. This reflects the weapons' different physical requirements, since these points come from historically independent regions and periods. These patterns are not replicated in ethnographic arrows, which are consistently larger than archaeological arrows. We suggest they not be used in archaeological comparisons. Hafted darts are notably larger than unhafted darts from archaeological sites, which is mostly due to use-life reductions. We suggest that there is no universally applicable data set, nor derived formula or index, that can be used to identify archaeological points as darts or arrows. We recommend nonparametric comparisons focusing on natural breaks in cross-cultural archaeological data. [ABSTRACT FROM AUTHOR]

We present a discriminant metric study of stone projectile points (n = 422) from 21 archaeological sites in the Andes of South America (16–37°S). We use comparative datasets critically, since darts may have been smaller than previously thought. We assess the use-life of each point and tie them to reliable chronological sequences, in order to increase the reliability of our data. Our results show that in the Lake Titicaca Basin and northwestern Argentina, bows had replaced spearthrowers by 1780–950 cal BP, prior to the development of complex societies such as Wari and Tiwanaku. South of 29°S, the results suggest that bow technology was transmitted from north to south, since the earliest arrow-sized points at 29°S date to 3000 cal BP and at 37°S, 1800–1000 cal BP. North of 34°S, the continental limit of domesticated plants and animals, there is a gradual abandonment of the spearthrower. South of 34°S in northern Patagonia, both weapon systems coexisted. We suggest that bow and arrow technology was not an independent invention in the southern Andes, but instead, it appeared in new groups via macroregional technological borrowing among Andean herders. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "The Assessment of Cytotoxicity, Apoptosis Inducing Activity and Molecular Docking of a new Ciprofloxacin Derivative in Human Leukemic Cells" published in the Journal of Fluorescence. The corrections include changes to the affiliation of the corresponding author and the order of images in the article. The corrected order of figures is provided, along with descriptions of the graphs. The original article has been corrected. The publisher remains neutral and does not endorse any jurisdictional claims or institutional affiliations. [Extracted from the article]

This article examines the diagnosis and treatment of diffuse alopecia areata (AA) in children. Diffuse AA is characterized by widespread hair loss on the scalp and is often misdiagnosed. The study found that there was a delay in diagnosis, possibly due to misdiagnosis or delayed medical help-seeking. Trichoscopy was found to be helpful in distinguishing diffuse AA from other conditions. Topical corticosteroids were the most commonly prescribed treatment, and over half of the patients experienced complete hair regrowth regardless of the treatment used. The study acknowledges its limitations and calls for further research on this unique presentation of AA in children. [Extracted from the article]

This article, published in the journal Plant Pathology, explores the role of trichomes in wheat susceptibility to Fusarium head blight (FHB), a fungal disease that affects wheat worldwide. The study focuses on the infection process of Fusarium graminearum, the predominant causal species for FHB, and describes how the fungus invades the base of trichomes on wheat florets. The research findings suggest that reducing trichome density and thickening the trichome base through genetic engineering could potentially improve wheat resistance to FHB. The article provides valuable insights into the nature of the infection process and may contribute to the development of FHB-resistant wheat cultivars. [Extracted from the article]

We give an integer linear program formulation for the star bicolouring of bipartite graphs. We develop a column generation method to solve the linear programming relaxation to obtain a lower bound for the minimum number of colours needed. We determine the star bicolouring using the iterative rounding method. We give computational results on arrowhead matrices, sparse random matrices, complete bipartite graphs, and matrices from the Harwell–Boeing collection. The findings demonstrate that the proposed method effectively establishes lower and upper bounds for the minimum number of colours needed for a star bicolouring of bipartite graphs, particularly for sparse bipartite graphs. [ABSTRACT FROM AUTHOR]

The "Arrow pin technique" is a modified version of using intramedullary pins to mend femoral diaphyseal/metaphyseal (supracondylar) fractures. The arrow pins were "custom made" by cutting locally available stainless-steel rod into predetermined lengths pins, further flattening one end, creating groves on either side of the flattened end with a file to give the appearance of an arrowhead, and shaping the opposite end as a trocar point. The pin insertion was accomplished aseptically through lateral approach on the distal femur, through the trochlear groove under general anaesthesia in cats. The clinical efficacy of this arrow pin technique was evaluated in six cats. All the cats (n=6) were client owned and < 1-year-old, with supracondylar distal femoral fractures. Following the clinical and radiological examinations, the type and location of the fracture, details of the fixation method applied, postoperative clinical and radiological results were assessed. After radiographic evaluation, long bone fractures were classified as supracondylar fractures of type I overridden closed fractures. Following the insertion of an intramedullary arrow pin, robust stability was accomplished, as evidenced radiographically. The patients were able to bear weight on the affected limb in 3-5 days and began walking normally on day 14 after surgery. The study found that the single "custom made" arrow pins provided adequate stability and resistance to rotational and axial forces in distal femoral fractures, and it confirmed that it would provide a significant fracture reduction in long bone fractures in young cats at a low cost. [ABSTRACT FROM AUTHOR]

Статья посвящена типологическому и хронологическому анализу костяных и бронзовых наконечников стрел, обнаруженных в могильниках и слоях поселений Ставропольской возвышенности IX — первой половины VIII — середины VII вв. до н.э. Стрелы обнаружены в грунтовых могильниках (могильник № 1 Томузловского городища; могильник № 1 Грушевского городища; могильник № 2 Татарского городища), в слоях поселений (Грушевское городище; находки в северо-западных окрестностях г. Ставрополя и на горе Стрижамент) и др. Костяные наконечники (7 экз.) относятся к двум группам: черешковые — 1 экз.; втульчатые — 6 экз. Бронзовые наконечники представлены четыремя группами: площики и полуплощик — 3 экз.; стрелы черногоровского типа — 2 экз.; втульчатые новочеркасского типа — 9 экз.; наконечники горизонта Жаботин — 45 экз. Набор стрел, характерных для различных хронологических периодов в материалах могильника № 1 Томузловского городища (восточная часть Ставропольской возвышенности) позволяет отодвинуть начало функционирования данного городища к IX — первой половине VIII в. до н.э. В западной части Ставропольской возвышенности пока не известно погребений со стрелами ранее середины VIII в. до н.э., хотя отдельные находки в регионе предметов и кладов, представляющих более ранние периоды, известны. Типологический анализ форм наконечников, происходящих из могильника № 1 Томузловского городища, позволяет определить основные векторы связей местной воинской культуры: северо-западное направление (Северное Причерноморье); северо-восточное (Южное Приуралье и Центральная Азия) и южное направление (Закавказье, Малая Азия). Возможно, это связано с особенностями расположения городища — поблизости от истоков р. Томузловки (широтное направление в сторону Волги) и рядом с р. Калаус (меридиальное направление — в сторону Прикаспия). Южнее памятника (недалеко) расположен район Кавминвод. На запад от Прикалаусских высот цепочкой протянулась Ставропольская возвышенность, что позволяло достаточно безопасно перемещаться в сторону Северного Причерноморья. Найденная в могильнике № 1 Томузловского городища бронзовая заготовка двулопастного наконечника стрелы II типа, 2 варианта (по А.И. Мелюковой) VII — первой половины VI в. до н.э. свидетельствует о местном производстве (отливке) наконечников.

The article focuses on the detailed craftsmanship of micro-sized Mississippian flint arrowheads, drills, and blowgun points dating from 1000 to 200 BP. Topics include their potential use for hunting small game or as blowgun dart tips, the role of the Cherokee in blowgun hunting, and the history of the miniature points' acquisition from Cherokee native Moses Owl.

The article discusses a case study of hypotrichosis simplex in a Chinese family, focusing on a 3-year-old boy with sparse hair due to two novel mutations in the LSS gene. The mutations were identified through whole-exome sequencing and confirmed by Sanger sequencing, with further analysis showing a significant reduction in LSS protein expression in the affected individual. The study sheds light on the genetic basis of hypotrichosis simplex and its association with mutations in the LSS gene, providing valuable insights into the condition. [Extracted from the article]