Forgotten giants: Robust climate signal in pollarded trees

Producción CientíficaTree ring records are among the most valuable resources to create high-resolution climate reconstructions. Most climate reconstructions are based on old trees growing in inaccessible mountainous areas with low human activity. Therefore, reconstruction of climate conditions in lowlands is usually based on data from distant mountains. Albeit old trees can be common in humanized areas, they are not used for climate reconstructions. Pollarding was a common traditional management in Europe that enabled trees to maintain great vitality for periods exceeding the longevity of unmanaged trees. We evaluate the potential of pollarded deciduous oaks to record past climate signal. We sampled four pollarded woodlands in Central Spain under continental Mediterranean climate. We hypothesized that pollarded trees have a strong response to water availability during current period without pollarding management, but also in the period under traditional management if pruning was asynchronous among trees. Moreover, we hypothesized that if climate is a regional driver of oak secondary growth, chronologies from different woodlands will be correlated. Pollard oaks age exceeded 500 years with a strong response to Standardized Precipitation-Evapotranspiration Index (SPEI) from 9 to 11 months. Climate signal was exceptionally high in three of the sites (r2 = 0.443–0.655) during low management period (1962–2022). The largest fraction of this climate signal (≈70 %) could be retrieved during the traditional management period (1902–1961) in the three sites where pollarding was asynchronous. Chronologies were significantly correlated since the 19th century for all the studied period, highlighting a shared climate forcing. We identified critical points to optimize pollard tree sampling schema. Our results show the enormous potential of pollarded woodlands to reconstruct hydroclimate conditions in the Mediterranean with a fine spatial grain. Studying pollarded trees is an urgent task, since the temporal window to retrieve the valuable information in pollarded trees is closing as these giants collapse and their wood rots.Junta de Castilla y León-Consejería de Educación [IR2020-1-UVA08; VA171P20]EU LIFE Soria Forest Adapt [LIFE19 CCA/ES/001181]Ministerio de Ciencia e Innovación - AEI (IJC2019-040571-I)Ministerio de Ciencia e Innovación - AEI (PRE2018-084106

Body Segment Differences in Surface Area, Skin Temperature and 3D Displacement and the Estimation of Heat Balance during Locomotion in Hominins

The conventional method of estimating heat balance during locomotion in humans and other hominins treats the body as an undifferentiated mass. This is problematic because the segments of the body differ with respect to several variables that can affect thermoregulation. Here, we report a study that investigated the impact on heat balance during locomotion of inter-segment differences in three of these variables: surface area, skin temperature and rate of movement. The approach adopted in the study was to generate heat balance estimates with the conventional method and then compare them with heat balance estimates generated with a method that takes into account inter-segment differences in surface area, skin temperature and rate of movement. We reasoned that, if the hypothesis that inter-segment differences in surface area, skin temperature and rate of movement affect heat balance during locomotion is correct, the estimates yielded by the two methods should be statistically significantly different. Anthropometric data were collected on seven adult male volunteers. The volunteers then walked on a treadmill at 1.2 m/s while 3D motion capture cameras recorded their movements. Next, the conventional and segmented methods were used to estimate the volunteers' heat balance while walking in four ambient temperatures. Lastly, the estimates produced with the two methods were compared with the paired t-test. The estimates of heat balance during locomotion yielded by the two methods are significantly different. Those yielded by the segmented method are significantly lower than those produced by the conventional method. Accordingly, the study supports the hypothesis that inter-segment differences in surface area, skin temperature and rate of movement impact heat balance during locomotion. This has important implications not only for current understanding of heat balance during locomotion in hominins but also for how future research on this topic should be approached

A model of human physiology and comfort for assessing complex thermal environments

The Berkeley Comfort Model is based on the Stolwijk model of human thermal regulation but includes several signi/cant improvements. Our new model allows an unlimited body segments (compared to six in the Stolwijk model). Each segment is modeled as four body layers (core, muscle, fat, and skin tissues) and a clothing layer. Physiological mechanisms such as vasodilation, vasoconstriction, sweating, and metabolic heat production are explicitly considered. Convection, conduction (such as to a car seat or other surface in contact with any part ofthe body) and radiation between the body and the environment are treated independently. The model is capable ofpredicting human physiological response to transient, non-uniform thermal environments. This paper describes the physiological algorithms as well as the implementation ofthe model. c 2001 Elsevier Science Ltd. All rights reserved

Paul Brönnle. Monuments of arabic philology. Commentary on Ibn Hischâm's biography of Muhammad according to Abu Dzarrs mss. in Berlin, Constantinople and the Escorial.

Houdas O. Paul Brönnle. Monuments of arabic philology. Commentary on Ibn Hischâm's biography of Muhammad according to Abu Dzarrs mss. in Berlin, Constantinople and the Escorial.. In: Journal des savants. 10ᵉ année, Mai 1912. pp. 233-234

Paul Brönnle. Monuments of arabic philology. Commentary on Ibn Hischâm's biography of Muhammad according to Abu Dzarrs mss. in Berlin, Constantinople and the Escorial.

Houdas O. Paul Brönnle. Monuments of arabic philology. Commentary on Ibn Hischâm's biography of Muhammad according to Abu Dzarrs mss. in Berlin, Constantinople and the Escorial.. In: Journal des savants. 10ᵉ année, Mai 1912. pp. 233-234

Marcel Cohen. Le parler arabe des Juifs d'Alger

Houdas O. Marcel Cohen. Le parler arabe des Juifs d'Alger. In: Journal des savants. 11ᵉ année, Avril 1913. pp. 184-186

Marcel Cohen. Le parler arabe des Juifs d'Alger

Houdas O. Marcel Cohen. Le parler arabe des Juifs d'Alger. In: Journal des savants. 11ᵉ année, Avril 1913. pp. 184-186