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Aridoamerica and Mesoamerica are two distinct cultural areas in northern and central Mexico, respectively, that hosted numerous pre-Hispanic civilizations between 2500 BCE and 1521 CE. The division between these regions shifted southward because of severe droughts ~1100 years ago, which allegedly drove a population replacement in central Mexico by Aridoamerican peoples. In this study, we present shotgun genome-wide data from 12 individuals and 27 mitochondrial genomes from eight pre-Hispanic archaeological sites across Mexico, including two at the shifting border of Aridoamerica and Mesoamerica. We find population continuity that spans the climate change episode and a broad preservation of the genetic structure across present-day Mexico for the past 2300 years. Lastly, we identify a contribution to pre-Hispanic populations of northern and central Mexico from two ancient unsampled “ghost” populations.

Resumen El puercoespín pardo, Coendou vestitus, se encuentra entre los roedores endémicos más amenazados de Colombia, con presencia corroborada en pocas localidades de la cordillera Oriental, en los departamentos de Boyacá y Cundinamarca. Presentamos registros recientes para tres localidades y observaciones de historia natural, como horarios de actividad y el uso de la cola a manera de soporte durante el desplazamiento. Como parte del conocimiento local se ha identificado el uso de sus púas como defensa ante animales domésticos y el consumo de cañas de chusque (Chusquea sp.), al igual que el uso de las espinas por parte de pobladores de las zonas de registro, relacionado con sus creencias. Nuestros registros, amplían a diez el número de localidades para el flanco occidental de la cordillera Oriental, en la ecorregión Selvas Montanas del Valle del Magdalena. Los registros fueron obtenidos durante el día y la noche, lo que hace necesario estudiar los patrones de actividad de los Coendou, generalizados como nocturnos, y obtener nuevos datos sobre la historia natural de esta especie. Abstract The brown hairy dwarf porcupine Coendou vestitus is among the most threatened endemic rodent species, with a corroborated presence in few localities in the Eastern Cordillera; departments of Boyacá and Cundinamarca. We present new records for three localities and natural history observations such as the use of the tail as a support during locomotion and activity hours. As part of local knowledge, the use of their quills as defense against domestic animals and the consumption of chusque (Chusquea sp.) has been identified, as well as the use of the quills by local people in the localities of the records related to their beliefs. Our records extend to 10 the number of localities for the western flank of the Eastern Cordillera, in the Magdalena Valley Montane Forests ecoregion. The records were obtained during the day and at night, so it is necessary to study the activity patterns within Coendou, generalized as nocturnal, and obtain new data on the natural history of this species.

In Argentina, during the last decade a southward expansion of the mosquito Aedes aegypti has been observed, accompanied by an expansion in the dengue transmission. The objective of this study was to assess the establishment of the dengue mosquito vector in a locality next to its distribution limits by a collaborative work among scientific, municipal and citizen ambits.A vector surveillance system through ovitraps was implemented, and it was complemented by pictures and mosquitoes captured by citizens, and by the active search of breeding sites in different urban spaces of Tandil City, Argentina.The establishment of Aedes aegypti population in the city was demonstrated, both by ovitraps and citizen science contributions. This information made it possible to begin to make the problem visible among municipal authorities and citizens.Dengue is an invisible disease in localities in which the mosquito vector has been spreading during the last decade. The information produced by the entomological surveillance is the necessary basis to addresssocial communication to produce behavioral changes in the responsible authorities as well as in the families.Introducción: En Argentina, durante la última década se ha observado una expansión hacia el sur del mosquito Aedes aegypti, acompañada por la expansión en la transmisión del dengue. El objetivo de este estudio fue evaluar el establecimiento de Ae. aegypti en una localidad cercana al límite de su distribución mediante un trabajo colaborativo entre los ámbitos científico, municipal, y ciudadano. Métodos: Se implementó un sistema de vigilancia del vector mediante ovitrampas, el cual se complementó con fotografías y ejemplares aportados por los ciudadanos, y con búsqueda activa de criaderos del mosquito en distintos espacios urbanos de la ciudad de Tandil, Argentina. Resultados: Se demostró el establecimiento de una población de Ae. aegypti en el municipio, tanto por medio de las ovitrampas como por los aportes del conocimiento y participación de la comunidad: la ciencia ciudadana. La información obtenida permitió comenzar a visibilizar la problemática entre los funcionarios municipales y la ciudadanía. Discusión: El dengue es una enfermedad aún invisible en localidades donde se ha estado expandiendo el mosquito vector durante la última década. La participación pública y la información producida con la vigilancia entomológica es la base necesaria para abordar la comunicación social a fin de producir cambios de conducta en las autoridades responsables y en las familias.

Aridoamerica and Mesoamerica are two distinct cultural areas that hosted numerous pre-Hispanic civilizations between 2,500 BCE and 1,521 CE. The division between these regions shifted southward due to severe droughts ca. 1,100 years ago, allegedly driving demographic changes and population replacement in some sites in central Mexico. Here, we present shotgun genome-wide data from 12 individuals and 26 mitochondrial genomes from eight pre-Hispanic archaeological sites across Mexico, including two at the shifting border of Aridoamerica and Mesoamerica. We find population continuity spanning the climate change episode and a broad preservation of the genetic structure across present-day Mexico for the last 2,300 years. Lastly, we identify a contribution to pre-Hispanic populations of northern and central Mexico from an ancient unsampled ‘ghost’ population.

Background The temporal muscle (TM) needs to be dissected and reflected downward in some anterolateral cranial approaches, and failing to preserve its integrity could have severe functional and cosmetic consequences. Most articles focus on techniques to prevent vascular injury during retrograde dissection or techniques to preserve the facial nerve; however, information on how to take care of the muscle during hook retraction is limited. We presented an anatomic study of vascularization of the TM, and we established safe areas for muscular hook retraction. Methods We dissected 16 TMs in 8 cadaveric heads. The TM was reflected downward, and we measured the distance between the anterior branch of the posterior deep temporal artery (PDTA) and the frontozygomatic suture and the distance between the posterior branch of the PDTA and the external auditory meatus projection. Results The average distance between the anterior branch of the PDTA and the frontozygomatic suture was 19.5 mm (range, 14–26 mm). The average distance between the posterior branch of the PDTA and the external auditory canal was 37.1 mm (range, 31–43 mm). We established 2 safe zones for hook placement: an anterior safe zone 14 mm posterior to the frontozygomatic suture and a posterior safe zone 30 mm anterior to the external auditory meatus. Conclusions We delimited 2 safe zones for hook placement during TM retraction aiming to avoid direct vascular damage in anterolateral cranial approaches.

We report a patient with reflex tooth-brushing-triggered epilepsy, associated with a post-central lesion within the right somatosensory face area. Contralateral facial sensory and motor phenomena, associated with contralateral upper limb extension, were present at seizure onset after gingival stimulation, but seizures could also be induced by contact with solid food or liquids. Spontaneous seizures also were recorded. Secondary generalization was infrequent. Stereoelectroencephalography implantation was performed, with seizure recording and cortical/subcortical stimulation for mapping, to identify the precise extent of surgical resection. Complete postoperative control of epilepsy was achieved, accompanied by a mild and transient neurological deficit. [Published with video sequence].

Epigenetic changes have been identified as a major driver of fundamental metabolic pathways. More specifically, the importance of epigenetic regulatory mechanisms for biological processes like speciation and embryogenesis has been well documented and revealed the direct link between epigenetic modifications and various diseases. In this review, we focus on epigenetic changes in animals with special attention on human DNA methylation utilizing ancient and modern genomes. Acknowledging the latest developments in ancient DNA research, we further discuss paleoepigenomic approaches as the only means to infer epigenetic changes in the past. Investigating genome-wide methylation patterns of ancient humans may ultimately yield in a more comprehensive understanding of how our ancestors have adapted to the changing environment, and modified their lifestyles accordingly. We discuss the difficulties of working with ancient DNA in particular utilizing paleoepigenomic approaches, and assess new paleoepigenomic data, which might be helpful in future studies.

The genetic makeup of Indigenous populations inhabiting Mexico has been strongly influenced by geography and demographic history. Here, we perform a genome-wide analysis of 716 newly genotyped individuals from 60 of the 68 recognized ethnic groups in Mexico. We show that the genetic structure of these populations is strongly influenced by geography, and our demographic reconstructions suggest a decline in the population size of all tested populations in the last 15–30 generations. We find evidence that Aridoamerican and Mesoamerican populations diverged roughly 4–9.9 ka, around the time when sedentary farming started in Mesoamerica. Comparisons with ancient genomes indicate that the Upward Sun River 1 (USR1) individual is an outgroup to Mexican/South American Indigenous populations, whereas Anzick-1 was more closely related to Mesoamerican/South American populations than to those from Aridoamerica, showing an even more complex history of divergence than recognized so far., Indigenous populations, including in those in Mexico are underrepresented in genetic studies. Here, the authors perform a population genetics study of indigenous peoples in Mexico to explore demographic histories of the region in the context of geography and cultural influences.

Objective Through a cadaveric study, we divided the cerebral central core (CCC) into different areas and have proposed a corresponding neurosurgical approach for each sector. As a secondary objective, we analyzed the cortical and subcortical microsurgical anatomy of the CCC. The CCC includes the insula, extreme capsule, claustrum, external capsule, lenticular nucleus, internal capsule, caudate nucleus, and thalamus. Methods Twelve adult human brain hemispheres and one cadaveric head specimen were dissected and studied at the Laboratory of Neuroanatomic Microsurgical of the University of Buenos Aires. Nine cases of CCC neurosurgical pathologies were included in the present study and analyzed. Digital drawings were created of the approaches proposed for each sector of the CCC showing the most relevant surgical details. Photographs of each dissection and measurements obtained were taken. Results We divided the CCC into a medial, intermediate, and lateral sector, with specific subdivisions for the lateral and medial sectors. The lateral projection of the foramen of Monro was found deep to the third short gyri of the insula with the following distances: anterior insular limen margin, 23.95 mm; posterior insular limen margin, 22.92 mm; superior limiting sulcus, 14.99 mm, and inferior limiting sulcus, 13.76 mm. We have proposed the following approaches: an ipsilateral transcallosal approach, a contralateral transcallosal approach, a choroidal transfissure approach, a trans-splenial approach, transparietal access entering the intraparietal sulcus, and trans-sylvian approach. The preoperative imaging studies should be analyzed using our method to select the most accurate and safe approach. Conclusions We have provided a description of the limits and anatomy of the CCC using brain dissection, an analysis of operated cases, and useful measurements for the neurosurgeon.

Se ha observado que el uso de imágenes interfiere en el aprendizaje de palabras novedosas. Se buscó extender estos resultados a Clases de Equivalencia de Estímulo (CEE), indagando si el efecto de bloqueo se presenta de manera diferencial según la modalidad del estímulo bloqueado (i.e. pictórico o pseudo-lexical). Diez estudiantes universitarios fueron entrenados, mediante igualación a la muestra, en cuatro CEE (dos de modalidad pseudo-lexical y dos de modalidad pictórica). En el mismo entrenamiento se aplicó un procedimiento de bloqueo. Se evaluó la emergencia de relaciones derivadas para cada elemento de los estímulos compuestos por separado. Un mayor efecto de bloqueo fue observado siempre que el estímulo bloqueado X fue de modalidad pseudo-lexical. Se discuten los resultados en relación a las teorías de emparejamiento de estímulos y su implicancia en el desarrollo de prácticas pedagógicas. Los resultados observados desalientan el uso de estímulos compuestos para la enseñanza de palabras.

Sward structure and animal grazing behaviour are key variables in determining herbage intake. The present study was carried out with the objective of evaluating the effect of different sward heights (SH) on the short-term ingestive behaviour variables, in steers grazing winter oats (Avena sativa cv. Calen). Six Holstein-Friesian steers (196 ± 4 kg LW), grouped into three pairs, grazed on swards with different surface heights (SH): 40 cm (SH40), 50 cm (SH50), and 60 cm (SH60). Short-term intake rates (IR) were estimated during grazing sessions of 1 h by the double-weighing technique with correction for insensible weight losses. The number of grazing jaw movements (GJM) and bite jaw movements were measured using the acoustic recorder technique. Measurements were conducted along three consecutive days. On each day, the pairs of steers grazed on one of the SH (1 pair per SH per d). Sound files were analysed visually and aurally. Number of GJM and BJM were determined during three 5-min periods, from minute 5 to 10, from minute 27 to 32 and from minute 50 to 55 of the 1 h grazing session. Bite mass (BM) was calculated as the quotient between IR and the number of bites. Variables of grazing behaviour were analysed by ANOVA according to a 3 × 3 Latin Square design. Classes included in the model were treatment, pair of animals, day, observation time window, and the interaction between treatment and observation time window. Unexpectedly, BM was not affected by the SH (P = 0.97; 0.59, 0.61 and 0.60 g DM bite−1, for SH40, SH50 and SH60, respectively). Similar BM were the result of a numerical, non-significant, decrease in IR (P = 0.65; 30.2, 29.6 and 26.3 g DM min−1, for SH40, SH50 and SH60, respectively), together with a decrease in bite rate (BR; P

The interaction between combinatorics and algebraic and differential geometry is very strong. While researching a problem of Hessian topology, we came across a series of identities of binomial coefficients, which are useful for proving a topological property of certain spaces whose elements are graphs of a class of hyperbolic polynomials. These identities are proven by different methods in combinatorics., Comment: 13 pages

This article reveals an investigation carried out on the production of ancestral thoughts from the rituals of many native populations of America (Abya Yala) in what has been called by the authors “Epistemologies of fire”. Here their ways of production, search and transmission of knowledge are set which, from the ancestral, have been used by indigenous communities for the construction of a community, privileging how each being thinks of itself inside a world view and a cosmic intelligence1 that allows for bases to be laid to confront the idea of internal and external separation, that has been pursued by human beings since the western construction of the world. Continuing with the idea elaborated by other authors of a pluriverse (a world where many worlds can fit), these epistemologies based in the recognition of diversity contribute as well to the construction of an academic polyphony that can recapture these native sciences to integrate their knowledge and the way of producing them to expand the perspectives in Social Sciences. Continuing with the idea woven by other authors of a pluriverse (a world where many worlds fit), these epistemologies based on the recognition of diversity also contribute to the construction of an academic polyphony that can take up these native sciences to integrate their knowledge and way to produce them to broaden the perspectives in the Social Sciences. An immersion work was developed using learning and description methodologies specific to the villages with which the work was carried out. This allowed us to carry out an exercise in careful listening to the spoken word of the elderly (knowledgeable grandparents) and participation in their rituals, which are understood as ancestral pedagogies.

Summary Multiple lines of evidence show that modern humans interbred with archaic Denisovans. Here, we report an account of shared demographic history between Australasians and Denisovans distinctively in Island Southeast Asia. Our analyses are based on ∼2.3 million genotypes from 118 ethnic groups of the Philippines, including 25 diverse self-identified Negrito populations, along with high-coverage genomes of Australopapuans and Ayta Magbukon Negritos. We show that Ayta Magbukon possess the highest level of Denisovan ancestry in the world—∼30%–40% greater than that of Australians and Papuans—consistent with an independent admixture event into Negritos from Denisovans. Together with the recently described Homo luzonensis, we suggest that there were multiple archaic species that inhabited the Philippines prior to the arrival of modern humans and that these archaic groups may have been genetically related. Altogether, our findings unveil a complex intertwined history of modern and archaic humans in the Asia-Pacific region, where distinct Islander Denisovan populations differentially admixed with incoming Australasians across multiple locations and at various points in time., Highlights • Comprehensive analyses of archaic ancestry among 118 Philippine ethnic groups • Ayta Magbukon display ∼30%–40% greater Denisovan ancestry than Australopapuans • The model is explained by a distinct admixture event into Negritos from Denisovans • Prior to modern humans, Islander Denisovans may have been present in the Philippines, Larena et al. reveal Philippine Ayta to possess the highest level of Denisovan ancestry in the world—∼30%–40% greater than that of Australopapuans—consistent with an independent admixture event into Negritos from Denisovans. The Philippine archipelago is thus likely inhabited by multiple archaic groups prior to the arrival of modern humans.

Significance A key link to understand human history in Island Southeast Asia is the Philippine archipelago and its poorly investigated genetic diversity. We analyzed the most comprehensive set of population-genomic data for the Philippines: 1,028 individuals covering 115 indigenous communities. We demonstrate that the Philippines were populated by at least five waves of human migration. The Cordillerans migrated into the Philippines prior to the arrival of rice agriculture, where some remain as the least admixed East Asians carrying an ancestry shared by all Austronesian-speaking populations, thereby challenging an exclusive out-of-Taiwan model of joint farming–language–people dispersal. Altogether, our findings portray the Philippines as a crucial gateway, with a multilayered history, that ultimately changed the genetic landscape of the Asia-Pacific region., Island Southeast Asia has recently produced several surprises regarding human history, but the region’s complex demography remains poorly understood. Here, we report ∼2.3 million genotypes from 1,028 individuals representing 115 indigenous Philippine populations and genome-sequence data from two ∼8,000-y-old individuals from Liangdao in the Taiwan Strait. We show that the Philippine islands were populated by at least five waves of human migration: initially by Northern and Southern Negritos (distantly related to Australian and Papuan groups), followed by Manobo, Sama, Papuan, and Cordilleran-related populations. The ancestors of Cordillerans diverged from indigenous peoples of Taiwan at least ∼8,000 y ago, prior to the arrival of paddy field rice agriculture in the Philippines ∼2,500 y ago, where some of their descendants remain to be the least admixed East Asian groups carrying an ancestry shared by all Austronesian-speaking populations. These observations contradict an exclusive “out-of-Taiwan” model of farming–language–people dispersal within the last four millennia for the Philippines and Island Southeast Asia. Sama-related ethnic groups of southwestern Philippines additionally experienced some minimal South Asian gene flow starting ∼1,000 y ago. Lastly, only a few lowlanders, accounting for

Let G be a finite subgroup of GL(n, C). This subgroup acts on the space of germs of holomorphic vector fields vanishing at the origin in Cn and on the group of germs of holomorphic diffeomorphisms of (Cn, 0). We prove a theorem of invariant conjugacy to a normal form and linearization for the subspace of invariant germs of holomorphic vector fields and we give a description of this type of normal forms in dimension n = 2.

BaxI-1, a cell death suppressor that modulates cell death induction in response to abiotic stress and pathogen attack in plants, is also involved in shaping the legume–rhizobia symbiosis., Bax-inhibitor 1 (BI-1) is a cell death suppressor conserved in all eukaryotes that modulates cell death in response to abiotic stress and pathogen attack in plants. However, little is known about its role in the establishment of symbiotic interactions. Here, we demonstrate the functional relevance of an Arabidopsis thaliana BI-1 homolog (PvBI-1a) to symbiosis between the common bean (Phaseolus vulgaris) and Rhizobium tropici. We show that the changes in expression of PvBI-1a observed during early symbiosis resemble those of some defence response-related proteins. By using gain- and loss-of-function approaches, we demonstrate that the overexpression of PvBI-1a in the roots of common bean increases the number of rhizobial infection events (and therefore the final number of nodules per root), but induces the premature death of nodule cells, affecting their nitrogen fixation efficiency. Nodule morphological alterations are known to be associated with changes in the expression of genes tied to defence, autophagy, and vesicular trafficking. Results obtained in the present work suggest that BI-1 has a dual role in the regulation of programmed cell death during symbiosis, extending our understanding of its critical function in the modulation of host immunity while responding to beneficial microbes.

The Late Neolithic period in Scandinavia [LN, c. 2350–1700 cal BCE] marks a time of considerable changes in settlement patterns, economy, and material culture. This shift also lays the foundation for the demographic developments in the Early Bronze Age [EBA, c. 1700–1100 cal BCE]. However, little is presently known regarding the developments from these time-periods on the island of Gotland in the Baltic Sea. During the Middle Neolithic period [MN, c. 3300–2350 cal BCE], Gotland was inhabited by groups associated with the Funnel Beaker culture [TRB, c. 4000–2700 cal BCE], and the sub-Neolithic Pitted Ware culture [PWC, c. 3300–2300 cal BCE]. Some indications of connections with the Battle Axe/Corded Ware cultures [BAC/CWC, c. 2800–2300 cal BCE] have also been found, but no typical BAC/CWC burials have been located on the island to date. Here, we investigate the chronological and internal relationship of twenty-three individuals buried in four LN/EBA stone cist burials; Haffinds, Hagur, Suderkvie, and Utalskog on Gotland. We present eleven mitochondrial genomes [from 23 X to 1271 X coverage], and twenty-three new radiocarbon dates, as well as stable isotope data for diet. We examine the local Sr-baseline range for Gotland, and present new Sr-data to discuss mobility patterns of the individuals. The genetic results are compared and discussed in light of earlier cultural periods from Gotland [TRB and PWC], and CWC from the European continent, as well as contemporaneous LN secondary burials in the MN Ansarve dolmen. We find that all burials were used into the EBA, but only two of the cists showed activity already during the LN. We also see some mobility to Gotland during the LN/EBA period based on Strontium and mitochondrial data. We see a shift in the dietary pattern compared to the preceding period on the island [TRB and PWC], and the two LN individuals from the Ansarve dolmen exhibited different dietary and mobility patterns compared to the individuals from the LN/EBA stone cist burials. We find that most of the cist burials were used by individuals local to the area of the burials, with the exception of the large LN/EBA Haffinds cist burial which showed higher levels of mobility. Our modeling of ancestral mitochondrial contribution from chronologically older individuals recovered in the cultural contexts of TRB, PWC and CWC show that the best model is a 55/45 mix of CWC and TRB individuals. A 3-way model with a slight influx from PWC [5%] also had a good fit. This is difficult to reconcile with the current archaeological evidence on the island. We suggest that the maternal CWC/TRB contribution we see in the local LN/EBA individuals derives from migrants after the Scandinavian MN period, which possible also admixed with smaller local groups connected with the PWC. Further genomic analyses of these groups on Gotland will help to clarify the demographic history during the MN to EBA time periods.

In recent years it has been shown that the Neolithization of Europe was partly driven by migration of farming groups admixing with local hunter-gatherer groups as they dispersed across the continent. However, little research has been done on the cultural duality of contemporaneous foragers and farming populations in the same region. Here we investigate the demographic history of the Funnel Beaker culture [Trichterbecherkultur or TRB, c. 4000–2800 cal BCE], and the sub-Neolithic Pitted Ware culture complex [PWC, c. 3300–2300 cal BCE] during the Nordic Middle Neolithic period on the island of Gotland, Sweden. We use a multidisciplinary approach to investigate individuals buried in the Ansarve dolmen, the only confirmed TRB burial on the island. We present new radiocarbon dating, isotopic analyses for diet and mobility, and mitochondrial DNA haplogroup data to infer maternal inheritance. We also present a new Sr-baseline of 0.71208 ± 0.0016 for the local isotope variation. We compare and discuss our findings together with that of contemporaneous populations in Sweden and the North European mainland. The radiocarbon dating and Strontium isotopic ratios show that the dolmen was used between c. 3300–2700 cal BCE by a population which displayed local Sr-signals. Mitochondrial data show that the individuals buried in the Ansarve dolmen had maternal genetic affinity to that of other Early and Middle Neolithic farming cultures in Europe, distinct from that of the contemporaneous PWC on the island. Furthermore, they exhibited a strict terrestrial and/or slightly varied diet in contrast to the strict marine diet of the PWC. The findings indicate that two different contemporary groups coexisted on the same island for several hundred years with separate cultural identity, lifestyles, as well as dietary patterns.

We study the second-order invariants of a Lorentzian surface in ℝ2,2, and the curvature hyperbolas associated with its second fundamental form. Besides the four natural invariants, new invariants appear in some degenerate situations. We then introduce the Gauss map of a Lorentzian surface and give an extrinsic proof of the vanishing of the total Gauss and normal curvatures of a compact Lorentzian surface. The Gauss map and the second-order invariants are then used to study the asymptotic directions of a Lorentzian surface and discuss their causal character. We also consider the relation of the asymptotic lines with the mean directionally curved lines. We finally introduce and describe the quasi-umbilic surfaces, and the surfaces whose four classical invariants vanish identically.