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Theoretical and empirical studies suggest that sea-level change was a fundamental parameter determining the distribution of fossil marine organisms. Although a similar relationship is generally assumed for the continental fossil record, this intuition remains speculative. Quantitative evidence reveals no correlation between sea-level variations and the distribution of continental tetrapods in the Late Jurassic-Eocene interval. The quality of the continental fossil record depends on many more factors than just eustatic changes. Keywords: Sea level, fossil record, Cretaceous, tetrapods.

In selecting the best freight forwarding company, the concept of a Decision Support System (DSS) can be used to find the best solution from several alternatives. One of the DSS methods is the Intuitionistic Fuzzy Analytical Hierarchy Process (IFAHP) and Intuitionistic Fuzzy Tomada de Decisao Interativa Multicriterio (IFTODIM). This study applied the IFAHP method combined with the IFTODIM method to select the best freight forwarding company at PT Progressio Indonesia. PT Progression Indonesia is a manufacturing and retail company that produces furniture. There are 11 criteria used in the performance assessment of the four alternatives. This research shows that the best freight forwarding company at PT Progressio Indonesia is Kobra Express, with a comprehensive value of 1.000. The second is Herona Express, with a comprehensive value of 0.9437, followed by Indah Logistik Cargo, with a comprehensive value of 0.7005. The last is Guna Dharma Express, with a comprehensive value of 0.0000.

This article provides a brief overview of current brain and learning research and discusses the implications of the research in meeting the needs of diverse learners in the classroom. The author describes dramatic developments in brain research related to brain structure, multiple intelligences, learning styles, emotions and learning, music and cognitive development, and brain-based learning. On the basis of the research, the author proposes the need for multifaceted, complex instruction and resource-rich environments for students. She asserts that each and every child has a unique brain and a great capacity to learn when exposed to relevant learning strategies., Teachers and administrators face enormous challenges to effectively prepare all students for a technological and global society. There is an ever-increasing diverse range of student abilities, as well as a [...]

Aborda una propuesta de contenidos para la interdisciplinariedad que debe dominar un egresado de Secundaria Básica, desde las ciencias naturales, para alcanzar la formación de un pensamiento con visión holística de la realidad. Considera las necesidades sociales de la realidad inmediata del escolar, se relaciona con los avances de la ciencia y la técnica y prevé que el escolar pueda influir positivamente en su solución. Contribuirá a prepararlos para enfrentar problemas de la vida cotidiana y de la elevación de la calidad de vida humana, de acuerdo con el desarrollo contemporáneo y con las necesidades sociales y económicas del país.

Aborda la aprendizaje relación de las interdisciplinariedad-integración ciencias naturales en en la Secundaria enseñanza– Básica. La interdisciplinariedad se concreta en el sujeto, al integrar los contenidos de diferentes ciencias que influyen en su relación con la naturaleza, la sociedad y el pensamiento. Los recursos didáctico-metodológicos establecidos son insuficientes para que el maestro oriente al alumno con enfoque interdisciplinar y que se apropie de los contenidos de manera integrada. Se favorece la descripción, explicación y demostración de su influencia en hechos y fenómenos relacionados con las necesidades vitales y contextos en que se desarrollan los escolares.

The mass extinction characterizing the Permian/Triassic boundary (PTB; ~ 252 Ma) corresponds to a major faunal shift between the Palaeozoic and the Modern evolutionary fauna. The temporal, spatial, environmental, and ecological dynamics of the associated biotic recovery remain highly debated, partly due to the scarce, or poorly-known, Early Triassic fossil record. Recently, an exceptionally complex ecosystem dated from immediately after the Smithian/Spathian boundary (~ 3 myr after the PTB) was reported: the Paris Biota (Idaho, USA). However, the spatiotemporal representativeness of this unique assemblage remained questionable as it was hitherto only reported from a single site. Here we describe three new exceptionally diverse assemblages of the same age as the Paris Biota, and a fourth younger one. They are located in Idaho and Nevada, and are taxonomic subsets of the Paris Biota. We show that the latter covered a region-wide area and persisted at least partially throughout the Spathian. The presence of a well-established marine fauna such as the Paris Biota, as soon as the early Spathian, indicates that the post-PTB biotic recovery and the installation of complex ecosystems probably took place earlier than often assumed, at least at a regional scale., (© 2021. The Author(s).)

Background: Many pathologies that modify the shell geometry and ornamentation of ammonoids are known from the fossil record. Since they may reflect the developmental response of the organism to a perturbation (usually a sublethal injury), their study is essential for exploring the developmental mechanisms of these extinct animals. Ammonoid pathologies are also useful to assess the value of some morphological characters used in taxonomy, as well as to improve phylogenetic reconstructions and evolutionary scenarios., Results: We report on the discovery of an enigmatic pathological middle Toarcian (Lower Jurassic) ammonoid specimen from southern France, characterized by a pronounced left-right asymmetry in both ornamentation and suture lines. For each side independently, the taxonomic interpretations of ornamentation and suture lines are congruent, suggesting a Hildoceras semipolitum species assignment for the left side and a Brodieia primaria species assignment for the right side. The former exhibits a lateral groove whereas the second displays sinuous ribs. This specimen, together with the few analogous cases reported in the literature, lead us to erect a new forma-type pathology herein called "forma janusa" for specimens displaying a left-right asymmetry in the absence of any clear evidence of injury or parasitism, whereby the two sides match with the regular morphology of two distinct, known species., Conclusions: Since "forma janusa" specimens reflect the underlying developmental plasticity of the ammonoid taxa, we hypothesize that such specimens may also indicate unsuspected phylogenetic closeness between the two displayed taxa and may even reveal a direct ancestor-descendant relationship. This hypothesis is not, as yet, contradicted by the stratigraphical data at hand: in all studied cases the two distinct taxa correspond to contemporaneous or sub-contemporaneous taxa. More generally, the newly described specimen suggests that a hitherto unidentified developmental link may exist between sinuous ribs and lateral grooves. Overall, we recommend an integrative approach for revisiting aberrant individuals that illustrate the intricate links among shell morphogenesis, developmental plasticity and phylogeny.

In the wake of the end-Permian mass extinction, the Early Triassic (~251.9 to 247 million years ago) is portrayed as an environmentally unstable interval characterized by several biotic crises and heavily depauperate marine benthic ecosystems. We describe a new fossil assemblage-the Paris Biota-from the earliest Spathian (middle Olenekian, ~250.6 million years ago) of the Bear Lake area, southeastern Idaho, USA. This highly diversified assemblage documents a remarkably complex marine ecosystem including at least seven phyla and 20 distinct metazoan orders, along with algae. Most unexpectedly, it combines early Paleozoic and middle Mesozoic taxa previously unknown from the Triassic strata, among which are primitive Cambrian-Ordovician leptomitid sponges (a 200-million year Lazarus taxon) and gladius-bearing coleoid cephalopods, a poorly documented group before the Jurassic (~50 million years after the Early Triassic). Additionally, the crinoid and ophiuroid specimens show derived anatomical characters that were thought to have evolved much later. Unlike previous works that suggested a sluggish postcrisis recovery and a low diversity for the Early Triassic benthic organisms, the unexpected composition of this exceptional assemblage points toward an early and rapid post-Permian diversification for these clades. Overall, it illustrates a phylogenetically diverse, functionally complex, and trophically multileveled marine ecosystem, from primary producers up to top predators and potential scavengers. Hence, the Paris Biota highlights the key evolutionary position of Early Triassic fossil ecosystems in the transition from the Paleozoic to the Modern marine evolutionary fauna at the dawn of the Mesozoic era.

The fossiliferous area of Toros-Menalla (TM) (Djurab Desert, northern Chad) has yielded one of the richest African mammal faunas of the late Miocene. It is also the place where the earliest known hominin, Sahelanthropus tchadensis, was found. Although more than 300 localities are recorded in that area, previous paleoecological studies focused only on the largest and richest one. The integration of the material from other TM localities, and thus of a significant number of mammal taxa, is crucial to improve the corresponding paleoenvironmental reconstructions. Before such inferences can be drawn, it is necessary to test for the ecological integrity of these mammal assemblages: how many paleocommunities do they represent? The faunal structures of several assemblages selected for their apparent resilience to sampling biases are compared here. The criteria used in the inter-assemblage comparison are ecological diversity, taxonomic structure (taxonomic rank of abundance) and taxonomic composition. Based on multivariate analyses, two groups of TM assemblages can be distinguished. One of them contains the hominin-bearing assemblages. It is taxonomically richer and shows a wider ecological spectrum than its counterpart. The degree of taphonomic alteration undergone by the TM assemblages, as well as the distribution of amphibious mammals among them, suggest different depositional settings for these two groups of assemblages, the richest of which was probably associated with lower hydraulic energy. Overall, it seems that the TM assemblages recorded the same mammal paleocommunity preserved in two contrasted depositional settings. Moreover, the spatial overlap of these assemblages provides further evidence for the mosaic character of the landscape associated with S. tchadensis., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Conservation biologists and palaeontologists are increasingly investigating the phylogenetic distribution of extinctions and its evolutionary consequences. However, the dearth of palaeontological studies on that subject and the lack of methodological consensus hamper our understanding of that major evolutionary phenomenon. Here we address this issue by (i) reviewing the approaches used to quantify the phylogenetic selectivity of extinctions and extinction risks; (ii) investigating with a high-resolution dataset whether extinctions and survivals were phylogenetically clustered among early Pliensbachian (Early Jurassic) ammonites; (iii) exploring the phylogenetic and temporal maintenance of this signal. We found that ammonite extinctions were significantly clumped phylogenetically, a pattern that prevailed throughout the 6.6 Myr-long early Pliensbachian interval. Such a phylogenetic conservatism did not alter--or may even have promoted--the evolutionary success of this major cephalopod clade. However, the comparison of phylogenetic autocorrelation among studies remains problematic because the notion of phylogenetic conservatism is scale-dependent and the intensity of the signal is sensitive to temporal resolution. We recommend a combined use of Moran's I, Pearson's ϕ and Fritz and Purvis' D statistics because they highlight different facets of the phylogenetic pattern of extinctions and/or survivals.

Over the last decades, the critical study of fossil diversity has led to significant advances in the knowledge of global macroevolutionary patterns of biodiversity. The deep-time history of life on Earth results from background originations and extinctions defining a steady-state, nonstationary equilibrium occasionally perturbed by biotic crises and "explosive" diversifications. More recently, a macroecological approach to the large-scale distribution of extant biodiversity offered new, stimulating perspectives on old theoretical questions and current practical problems in conservation biology. However, time and space are practically distinct, but functionally related dimensions of ecological systems. This calls for a spatially-integrated study of biodiversity dynamics at an evolutionary timescale. Indeed, the biosphere is a complex adaptive system whose study cannot be arbitrarily reduced to any single spatial- and/or temporal-scale level of resolution without a loss of content. From such an integrated perspective, a simple fact emerges: in a physically heterogeneous and ever-changing world, spatiotemporal variations in biodiversity are the rule-not the exception., (Copyright © 2011 Académie des sciences. Published by Elsevier SAS. All rights reserved.)

Recent fossil discoveries have demonstrated that Africa and Asia were epicentres for the origin and/or early diversification of the major living primate lineages, including both anthropoids (monkeys, apes and humans) and crown strepsirhine primates (lemurs, lorises and galagos). Competing hypotheses favouring either an African or Asian origin for anthropoids rank among the most hotly contested issues in paleoprimatology. The Afrocentric model for anthropoid origins rests heavily on the >45 Myr old fossil Algeripithecus minutus from Algeria, which is widely acknowledged to be one of the oldest known anthropoids. However, the phylogenetic position of Algeripithecus with respect to other primates has been tenuous because of the highly fragmentary fossils that have documented this primate until now. Recently recovered and more nearly complete fossils of Algeripithecus and contemporaneous relatives reveal that they are not anthropoids. New data support the idea that Algeripithecus and its sister genus Azibius are the earliest offshoots of an Afro-Arabian strepsirhine clade that embraces extant toothcombed primates and their fossil relatives. Azibius exhibits anatomical evidence for nocturnality. Algeripithecus has a long, thin and forwardly inclined lower canine alveolus, a feature that is entirely compatible with the long and procumbent lower canine included in the toothcomb of crown strepsirhines. These results strengthen an ancient African origin for crown strepsirhines and, in turn, strongly challenge the role of Africa as the ancestral homeland for anthropoids.

Characterizing the paleoenvironmental context of the first hominids is a key issue for understanding their behavioral and morphological evolution. The present study aims at reconstructing the paleoenvironment of the TM266 vertebrate assemblage (Toros-Menalla, Northern Chad) that yielded the earliest known hominid Sahelanthropus tchadensis (7 Ma). For the first time, a quantitative analysis is carried out on the fossil mammal assemblage associated with that hominid. Two complementary approaches were applied: (1) the analysis of the relative abundances of taxa and their habitat preferences; and (2) the study of the distribution of taxa within three meaningful ecovariables: locomotion, feeding preferences, and body mass. The resulting taxonomic and paleoecological structures are used to reconstruct the diversity and the relative extent of the habitats in that part of northern Chad seven million years ago. The paleoenvironment was composed of open areas with dry and humid grasslands, prevailing over wooded habitats. Water was also widely available as freshwater bodies and certainly swamps. It appears that the high habitat diversity of the landscape is a common feature among paleoenvironments associated with early hominids.

Synodontis (Mochokidae, Siluriformes) is a freshwater catfish endemic to Africa. The 118 extant species are present in almost all hydrographic basins. Some species are restricted to a single stream, whereas others have a vast distribution. Synodontis is known in the fossil record since the Miocene, and its history depends on the connections among African basins through time. The identification of species in the fossil record is essential to reconstruct this historical pattern. Catfish pectoral and dorsal spines are robust, they preserve well and they form most of the fossil remains for the genus Synodontis. Unfortunately, the criteria for the identification of extant Synodontis species are not applicable to fossil specimens. Here, we define 11 original morphological characters that permit to discriminate four extant species from the Chad-Chari hydrographic system. Six of these characters are defined on pectoral spines and five on dorsal spines. We then show that these characters can be used successfully for identifying fossil specimens. In particular, we present a case study in which we identify Synodontis cf. schall and Brachysynodontis cf. batensoda in the hominid-bearing sector Toros-Menalla (Late Miocene, northern Chad). We show that spine anatomy can be a powerful tool to recognise catfish species through time and thus to identify historical diversity pattern.

Numerous Pliocene large-mammal assemblages have been discovered in Chad over the last decade. They offer a unique opportunity to understand the settings in which important chapters of Hominid evolution took place in Central Africa. However, it is crucial to first investigate both sampling and taxonomic homogeneity for these Chadian assemblages because they occur over large sectors in a sandy desert that offers virtually no stratigraphic section. Using cluster analysis and ordination techniques, we show that the three Pliocene sectors from Chad are homogeneous and adequate sampling units. Previous stable isotope analyses on these assemblages have indicated that the environment became richer in C(4) plants between approximately 5.3 and 3.5-3 Ma. To test whether this environmental change has affected the structure of palaeo-communities, we assigned body mass, trophic and locomotor eco-variables to mammal species from the three sectors. Statistical analysis shows that the overall ecological structure of the assemblages is not linked with the opening of the plant cover, and eco-variables show no temporal trend from the oldest sector to the youngest. For example, there is no significant change in the relative diversity of grazing and browsing taxa, although mixed feeders are less diversified in the youngest sector than in the preceding one. This pattern apparently does not result from potential biases such as methodological artefacts or taphonomic imprint. Instead, it seems that local heterogeneous environmental factors have played a major role in shaping the ecological spectrum of Chadian mammal palaeo-communities during the Pliocene.

Background: Chemotherapy regimens that target microtubular trafficking were repeatedly found to be active in the treatment of hormone refractory prostate cancer patients, but disease responses were reportedly short-lived on average., Materials and Methods: From 1994 to 1997, 46 consecutive patients with hormone refractory prostate cancer were enrolled in a multicenter Phase II trial of oral etoposide 100 mg/day and estramustine 560 mg/day for 21 days, followed by a 7-day rest period. Final evaluation of this trial was performed after a follow-up of 5 years., Results: Fifty-four percent of patients attained a PSA response and 46% attained a response on measurable lesions. Median time to progression (TTP) and overall survival were 7.4 and 18.4 months, respectively. Fourteen patients (30.4%) had a TTP greater than 12 months and 9 (19.5%) a TTP greater than 18 months. Sixteen patients (34.8.%) survived more than 2 years and 2 (4.3%) survived more than 5 years. One patient was still alive and free from progression more than 7 years after starting treatment., Conclusions: This Phase II trial with a long-term follow-up revealed that some patients with hormone refractory prostate cancer could obtain durable disease response and long survival with an oral etoposide and estramustine combination regimen.

The demonstrated association with hematologic neoplasms may partially account for the poor survival of patients with mediastinal nonseminomatous germ cell tumors (MNSGCT) compared to patients with testicular and retroperitoneal counterparts. It has been shown that the median interval from the diagnosis of MNSGCT to the diagnosis of the hematologic disorders is 6 months, which contrasts sharply with the average time of 2 to 3 years for the development of therapy-related leukemias. The 2 cases herein described, 1 male and 1 female, developed acute M2 leukemia 4 and 2 years after the diagnosis of MNSGCT. In the second patient (the first female ever described), we cannot exclude a pathogenetic role of the PEB regimen (platinum, etoposide, bleomicin), even though the total dose of etoposide administered has been demonstrated to have a mild leukemogenic potential. This is not the case of the first patient, who did not receive adjuvant chemotherapy after the radical resection of primary MNGSCT and developed the hematologic disorder a few months after local recurrence. In conclusion, the time elapsed from chemotherapy administration does not discriminate the hematologic neoplasms associated to MNGSCT from those related to therapy.

We sought to determine the capillary morphology in patients with clubbing to compare it with that in subjects without clubbing. Subjects were placed in the clubbed or nonclubbed groups on the basis of caliper measurements of their index fingers. In each subject, photomicrographs of eight fingers were done focusing on the dorsal skin just proximal to the base of the nail. Each photomicrograph was randomly graded with respect to the presence and extent of plexus formation, the presence of arborized loops, and the presence of splayed loops. Comparison of the plexus score, presence of arborized loops, and presence of splayed loops were significantly different between the clubbed and nonclubbed groups (p less than 0.001 in all three analyses). Only a plexus score of 2 or greater demonstrated a useful degree of sensitivity and specificity (89 and 90%, respectively). We concluded that a significant difference in the morphologic features of the capillaries existed between nonclubbed subjects and those with acquired clubbing.