Repeated aeolian deflation during the Allerød/GI-1a-c in the coversand lowland of NW Belgium

The results of multi-disciplinary research carried out on the deposits of the Moerbeke "Driehoek" site, located along the northern bank of the extensive Moervaart palaeolake (NW Belgium), are presented. The multi-proxy study, including sedimentological (organic matter, calcium carbonate and grain-size) and botanical (pollen, macrofossils, NPP) analyses, provided evidence of repeated aeolian deflation during the Allerod. Our results demonstrate, in combination with evidence from other soil archives within the Moervaart area, that the Allerod period in NW Europe was sedimentologically much less stable than hitherto assumed, especially during the GI-1c2 event and middle Allerod. Some of the Allerod deflation events were caused by centennial abrupt climatic oscillations, such as the short but pronounced cold GI-1c2 event, while others were likely the result of intense forest fires or a combination of both. These observations call for a revision of the existing Lateglacial litho- and chronostratigraphic schemes for the sand-belt of northern Europe

Порівняльна характеристика антропометричних показників, рівня фізичної та технічної підготовленості юних футболістів 12 та 15 років різних ігрових амплуа

Purpose: To develop model characteristics of physical and technical fitness of players of 12 and 15 years of different playing roles.Material and methods. The study was attended by football players of 12 and 15 years of sport school "Areal" Kharkiv, in which the developed technologies were applied in the educational process. In total, 23 forvards, 28 midfielders, 30 defenders and 15 goalkeepers were invited for the survey. Indicators of the running time of segments of 15 m from the course, 30 m from the course and 60 m from the course were determined; shuttle running time 5 to 20 m. Determined the length and weight of the body; Heart rate at rest and heart rate after a shuttle run. From the technical readiness indicators were determined: the time of holding the soccer ball on the foot; juggling, that is, the number of shots of the ball with the foot without losing the ball; time to run a soccer ball on a mission; goal kicks for accuracy; strikes the ball at flight range.Results. Young players of 12 and 15 years of different game specializations differ in terms of physical and technical fitness. The largest number of significant differences were found in the technical readiness of football players for 15 years. Field players at speed capabilities are significantly superior to goalkeepers. Goalkeepers, on the contrary, have lower running speeds. The level of speed endurance is relatively high for defenders and midfielders, as opposed to goalkeepers. The obtained data allowed us to build models of physical development, physical and technical readiness of players of 12 and 15 years of different playing fields, on the basis of which training programs for representatives of different playing roles can be developed.Conclusions. The data obtained indicate the need for a differentiated approach in the training process of young football players, taking into account their playing role. The differentiated approach is more relevant at the age of 15 compared to the age of 12.Цель: разработать модельные характеристики физической и технической подготовленности футболистов 12 и 15 лет разных игровых амплуа.Материал и методы. В исследовании приняли участие футболисты 12 та15 лет ДЮСШ «Ареал» г.. Харькова, в учебно-тренировочном процессе которых применялись разработаны технологии. Всего для обследования были приглашены 23 нападающих, 28 полузащитников, 30 защитников и 15 вратарей. Определялись показатели времени пробегания отрезков 15 м с ходу, 30 м с ходу и 60 м с хода; время челночного бега 5 по 20 м. Определяли длину и массу тела ЧСС покоя и ЧСС после челночного бега. Из показателей технической подготовленности определяли: время содержания футбольного мяча на стопе; жонглирование, то есть количество набивок мяча стопой без потери мяча; время выполнения ведения футбольного мяча по заданию; удары по воротам на точность попадания; удары мяча на дальность полета.Результаты. Юные футболисты 12 и 15 лет разных игровых специализаций различаются между собой по показателям физической и технической подготовленности. Наибольшее количество достоверных различий обнаружено в показателях технической подготовленности футболистов 15 лет.Полевые игроки по скоростным возможностям существенно превосходят вратарей. Вратари, наоборот, имеют более низкие показатели скорости бега. Уровень скоростной выносливости относительно высокий у защитников и полузащитников в отличие от вратарей.Выводы. Полученные данные свидетельствуют о необходимости дифференцированных устных подхода в тренировочном процессе юных футболистов с учетом их игрового амплуа. Дифференцированных устных подход приобретает большую актуальность в 15 лет по сравнению с возрастом 12 лет.Мета: розробити модельні характеристики фізичної та технічної підготовленості футболістів 12 та 15 років різних ігрових амплуа.Матеріал і методи. У дослідженні узяли участь футболісти 12 та15 років ДЮСШ «Ареал» м. Харкова, в навчально-тренувальному процесі яких застосовувалися розроблені технології. Всього для обстеження було запрошено 23 нападаючих, 28 півзахисників, 30 захисників і 15 воротарів. Визначалися показники часу пробігання відрізків15 м з ходу,30 м з ходу та 60 м з ходу; час човникового бігу 5 по20 м. Визначали довжину та масу тіла; ЧСС спокою та ЧСС після човникового бігу. З показників технічної підготовленості визначали: час тримання футбольного м’ча на стопі; жонглювання, тобто кількість набивань м’яча стопою без втрати м’яча; час виконання ведення футбольного м’яча за завданням; удари по воротам на точність влучення; удари м’яча на дальність польоту.Результати. Юні футболісти 12 і 15 років  різних ігрових спеціалізацій розрізняються між собою за показниками фізичної і технічної підготовленості. Найбільша кількість достовірних відмінностей виявлена у показниках технічної підготовленості футболістів 15 років.Польові гравці по швидкісних можливостях істотно перевершують воротарів. Воротарі, навпаки, мають нижчі показники швидкості бігу. Рівень швидкісної витривалості відносно високий у захисників і напівпівзахисників на відміну від воротарів. Отримані дані дозволили побудувати моделі фізичного розвитку, фізичної та технічної підготовленості футболістів 12 та 15 років різних ігрових амплуа, на основі яких можуть бути розроблені програми тренувань для представників різних ігрових амплуа.Висновки. Отримані дані свідчать про необхідність діференційованого підходу в тренувальному процесі юних футболістів з урахуванням їх ігрового амплуа. Діференційований підхід набуває більшу актуальність у 15 років у порівнянні з віком 12 років

H^+H^- Pair Production at the Large Hadron Collider

We study the pair production of charged Higgs bosons at the CERN Large Hadron Collider in the context of the minimal supersymmetric extension of the standard model. We compare the contributions due to qq-bar annihilation at the tree level and gg fusion, which proceeds at one loop. At small or large values of tan(beta), H^+H^- production proceeds dominantly via bb-bar annihilation, due to Feynman diagrams involving neutral CP-even Higgs bosons and top quarks, which come in addition to the usually considered Drell-Yan diagrams. In the case of gg fusion, the squark loop contributions may considerably enhance the well-known quark loop contributions.Comment: 15 pages (Latex), 4 figures (Postscript

All Static Circularly Symmetric Perfect Fluid Solutions of 2+1 Gravity

Via a straightforward integration of the Einstein equations with cosmological constant, all static circularly symmetric perfect fluid 2+1 solutions are derived. The structural functions of the metric depend on the energy density, which remains in general arbitrary. Spacetimes for fluids fulfilling linear and polytropic state equations are explicitly derived; they describe, among others, stiff matter, monatomic and diatomic ideal gases, nonrelativistic degenerate fermions, incoherent and pure radiation. As a by--product, we demonstrate the uniqueness of the constant energy density perfect fluid within the studied class of metrics. A full similarity of the perfect fluid solutions with constant energy density of the 2+1 and 3+1 gravities is established.Comment: revtex4, 8 page

An accelerated closed universe

We study a model in which a closed universe with dust and quintessence matter components may look like an accelerated flat Friedmann-Robertson-Walker (FRW) universe at low redshifts. Several quantities relevant to the model are expressed in terms of observed density parameters, $\Omega_M$ and $\Omega_{\Lambda}$, and of the associated density parameter $\Omega_Q$ related to the quintessence scalar field $Q$.Comment: 11 pages. For a festschrift honoring Alberto Garcia. To appear in Gen. Rel. Gra

Fiabilidad y validez de las mediciones en hombro y codo: análisis de una aplicación de Android y un goniómetro

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado.Carta al EditorRevisión por pare

Carbohydrate and protein metabolism of marandu grass affected by nitrogen fertilisation and number of cuts

Received: June 18th, 2023 ; Accepted: September 30th, 2023 ; Published: October 23rd, 2023 ; Correspondence: [email protected] the metabolism of tropical grasses in response to management practises imposed in pastoral environments allows for improvements in the management and use of mineral fertilisers. This study aimed to quantify metabolite content in different plant parts of Marandu grass (Urochloa brizantha), with a specific focus on the influence of nitrogen fertilisation and its effects following successive cuts. The treatments corresponded to four nitrogen (N) rates (0, 75, 150, and 225 kg N ha-1 ) and the number of cuts (one, two and three cuts). The plants were fractionated into leaves, stems, and roots to assess the content of water-soluble carbohydrates (WSC), starch, albumin, globulin, prolamin, and glutelin content. N fertilisation influenced the WSC and starch content in different parts of the plant, varying according to the cuts made. In the leaves and roots, fertilisation reduced the content of WSC and starch with one cut, as these were utilised as energy sources for assimilating the excess nitrogen in the soil. There was an increase in the concentration of all protein groups with nitrogen fertilisation in all parts of the plant with one cut. In plants cut two and three times, N fertilisation led to specific increases and decreases in different parts of the plants as an adaptive strategy for allocating resources as the number of cuts increased. Our results broaden our understanding of carbohydrate and protein metabolism in tropical grasses, thereby providing subsidies for the rational use of nitrogen fertilisers

Volcanic sequence in Late Triassic – Jurassicsiliciclastic and evaporitic rocks from Galeana, NE Mexico

In northeastern Mexico, volcanic rocks interbedded with Late Triassic–Jurassic siliciclastic and evaporitic strata have been linked to magmatic arcs developed in the Pangea western margin during its initial phase of fragmentation. This work provides new petrographic and geochemical data for volcanism included in the El Alamar and Minas Viejas formations outcropping in the Galeana region. Andesitic dykes and sills (n= 10) in the El Alamar redbeds show SiO2= 47.5–59.1% and MgO= 1.2–4.2%, as well as a geochemical affinity to island arc magmas. This work represents the first report of this tectonic setting in the region. Geological and petrographic evidence suggest that this arc system likely developed after ~220 and before ~193Ma. Trachy-andesitic and rhyodacitic domes (n= 20) associated with the Minas Viejas gypsum-carbonates sequence show SiO2= 61.8–82.7% and MgO= 0.1–4.0% with a tectonic affinity to continental arc. A rhyodacite sample from this region has been dated by U-Pb in zircon, yielding an age of 149.4 ± 1.2Ma (n= 21), being the youngest age related to this arc. Finally, we propose a threestep model to explain the tectonic evolution from Late Triassic island arc to Jurassic continental arc system in the northeastern Mexico

Leaders-cheaters in male group cooperation: differences in nonverbal communication and genetic factors

Here we report on the results of an experimental study investigating "who?" emerges as a leader in the context of male group cooperation and "how?" they do that. The study was designed based on the iterated Public Goods Game, played face-to-face in groups composed of four male strangers. The game involved interactions both with and without communication to allow the assessment of individual cooperative strategies, leadership potential, and individual features of positive nonverbal expressiveness during interactions. Along with the individual behavioural characteristics we have addressed personality traits (the Big Five) and an oxytocin receptor gene polymorphism (OXTR: SNP rs53576; A/G) as putative markers of individual sociability. Our results revealed that emergent leaders most often employed the strategy of unconditional cooperation ("altruism") and were characterized by enhanced positive facial expressiveness and extraversion compared to non-leaders. However, a fraction of emergent leaders (25%) turned out to be occasional free-riders ("cheaters"). Their distinctive features were the highest scores on extraversion, exaggerated activity in negotiations, and over-expression of positive nonverbal elements. Given the high efficiency of leaders-cheaters' behaviour, we consider this result as the evidence for supernormal stimuli functioning in humans. Moreover, leaders-cheaters were characterized by a specific allelic frequency of OXTR rs53576 (heterozygosity: AG). The homozygous GG variant of this SNP is argued to be associated with prosociality, and the AA, on the contrary, with poor sociability. The heterozygous variant (AG) probably is a compromise that enables its carriers to successfully combine high social skills with anti-social behavior (free-riding). This finding supports existing evidence on the role of OXTR rs53576 in human social behaviour

SU(1,1) Coherent States For Position-Dependent Mass Singular Oscillators

The Schroedinger equation for position-dependent mass singular oscillators is solved by means of the factorization method and point transformations. These systems share their spectrum with the conventional singular oscillator. Ladder operators are constructed to close the su(1,1) Lie algebra and the involved point transformations are shown to preserve the structure of the Barut-Girardello and Perelomov coherent states.Comment: 11 pages, 5 figures. This shortened version (includes new references) has been adapted for its publication in International Journal of Theoretical Physic