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This paper explores the nature and dynamics of adaptation and resilience in the face of a diverse and varied environmental and ecological context using the case study of South Asia’s Indus Civilization (ca. 3000–1300 BC). Most early complex societies developed in regions where the climatic parameters faced by ancient subsistence farmers were varied but rain falls primarily in one season. In contrast, the Indus Civilization developed in a specific environmental context that spanned a very distinct environmental threshold, where winter and summer rainfall systems overlap. There is now evidence to show that this region was directly subject to climate change during the period when the Indus Civilization was at its height (ca. 2500–1900 BC). The Indus Civilization, therefore, provides a unique opportunity to understand how an ancient society coped with diverse and varied ecologies and change in the fundamental environmental parameters. This paper integrates research carried out as part of the Land, Water and Settlement project in northwest India between 2007 and 2014. Although coming from only one of the regions occupied by Indus populations, these data necessitate the reconsideration of several prevailing views about the Indus Civilization as a whole and invigorate discussion about human-environment interactions and their relationship to processes of cultural transformation.

The geographic distribution of genetic diversity and the population structure of tetraploid wheat landraces in the Mediterranean basin has received relatively little attention. This is complicated by the lack of consensus concerning the taxonomy of tetraploid wheats and by unresolved questions regarding the domestication and spread of naked wheats. These knowledge gaps hinder crop diversity conservation efforts and plant breeding programmes. We investigated genetic diversity and population structure in tetraploid wheats (wild emmer, emmer, rivet and durum) using nuclear and chloroplast simple sequence repeats, functional variations and insertion site-based polymorphisms. Emmer and wild emmer constitute a genetically distinct population from durum and rivet, the latter seeming to share a common gene pool. Our population structure and genetic diversity data suggest a dynamic history of introduction and extinction of genotypes in the Mediterranean fields.

The frontier between Gubbio (ancient Umbria) and Perugia (ancient Etruria), in the northeast part of the modern region of Umbria, was founded in the late sixth century bc. The frontier endured in different forms, most notably in the late antique and medieval periods, as well as fleetingly in 1944, and is fossilized today in the local government boundaries. Archaeological, documentary and philological evidence are brought together to investigate different scales of time that vary from millennia to single days in the representation of a frontier that captured a watershed of geological origins. The foundation of the frontier appears to have been a product of the active agency of the Etruscans, who projected new settlements across the Tiber in the course of the sixth century bc, protected at the outer limit of their territory by the naturally defended farmstead of Col di Marzo. The immediate environs of the ancient abbey of Montelabate have been studied intensively by targeted, systematic and geophysical survey in conjunction with excavation, work that is still in progress. An overview of the development of the frontier is presented here, employing the data currently available. La frontiera tra Gubbio (antica Umbria) e Perugia (antica Etruria), nella parte nordorientale della moderna Umbria, è stata fondata nel tardo VI secolo a.C. La frontiera resistette in forme diverse, più significativamente nei periodi tardo-antico e medievale, altrettanto fugacemente nel 1944, ed è fossilizzata oggi nei locali confini amministrativi. L'evidenza archeologica, documentaria e filologica sono messe insieme per analizzare differenti scale di periodo che variano da millenni ai singoli giorni nella rappresentazione di una frontiera che catturava uno spartiacque di origini geologiche. La fondazione della frontiera appare essere stata il risultato di una mediazione attiva degli Etruschi, che proiettavano nuovi insediamenti attraverso il Tevere nel corso del VI secolo a.C., protetti verso i limiti più esterni del loro territorio dalla fattoria naturalmente difesa di Col di Marzo. Gli immediati dintorni dell'antica abbazia di Montelabate sono stati studiati intensivamente da una ricognizione mirata, sistematica e geofisica, unitamente ad uno scavo, tuttora in corso. Qui viene presentato uno sguardo sullo sviluppo della frontiera, includendo i dati attualmente disponibili.

The characterization of the neutron, prompt gamma-ray, and delayed gamma-ray radiation fields for the White Sands Missile Range (WSMR) Fast Burst Reactor, also known as molybdenum-alloy Godiva (Molly-G) has been assessed at the 6-inch irradiation location. The neutron energy spectra, uncertainties, and common radiation metrics are presented. Code-dependent recommended constants are given to facilitate the conversion of various dosimetry readings into radiation metrics desired by experimenters. The Molly-G core was designed and configured similarly to Godiva II, as an unreflected, unmoderated, cylindrical annulus of uranium-molybdenum-alloy fuel with molybdenum loading of 10%. At the 6-inch position, the axial fluence maximum is about 2.4×10 13 n/cm 2 per MJ of reactor energy; about 0.1% of the neutron fluence is below 1 keV and 96% is above 100 keV. The 1-MeV Damage-Equivalent Silicon (DES) fluence is estimated at 2.2×10 13 n/cm 2 per MJ of reactor energy. The prompt gamma-ray dose is roughly 2.5E+03 rad(Si) per MJ and the delayed gamma-ray dose is about 1.3E+03 rad(Si) per MJ.

Neurons on left and right sides of the nervous system frequently show asymmetric properties but how these differences arise is poorly understood. Through a forward genetic screen in zebrafish, we find that loss of function of the transmembrane protein Cachd1 results in right-sided habenular neurons adopting left-sided character. Cachd1 is expressed in habenular neuron progenitors, functions symmetrically downstream of asymmetric environmental signals that determine laterality and influences timing of the normally left-right asymmetric patterns of neurogenesis. Unbiased screening for Cachd1 partners identified the Wnt co-receptor Frizzled7 and further biochemical and structural analysis revealed Cachd1 can bind simultaneously to Fzd proteins and Lrp6, bridging between these two Wnt co-receptors. Consistent with these structural studies, lrp6 mutant zebrafish show symmetric habenulae with left-sided character and epistasis experiments with other Wnt pathway genes support an in vivo role for Cachd1 in modulating Wnt pathway activity in the brain. Together, these studies identify Cachd1 as a novel Wnt-receptor interacting protein with roles in regulating neurogenesis and neuronal identity. Competing Interest Statement The authors have declared no competing interest.