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•Examination of the effect of disconnectivity following stroke on multiplication.•WM between AG and superior temporal areas was associated with worse multiplication.•Disconnections in the arithmetic fact retrieval network led to worse multiplication.•White matter disconnectivity needs more examination in numerical cognition research. Arithmetic fact retrieval has been suggested to recruit a left-lateralized network comprising perisylvian language areas, parietal areas such as the angular gyrus (AG), and non-neocortical structures such as the hippocampus. However, the underlying white matter connectivity of these areas has not been evaluated systematically so far. Using simple multiplication problems, we evaluated how disconnections in parietal brain areas affected arithmetic fact retrieval following stroke. We derived disconnectivity measures by jointly considering data from n = 73 patients with acute unilateral lesions in either hemisphere and a white-matter tractography atlas (HCP-842) using the Lesion Quantification Toolbox (LQT). Whole-brain voxel-based analysis indicated a left-hemispheric cluster of white matter fibers connecting the AG and superior temporal areas to be associated with a fact retrieval deficit. Subsequent analyses of direct gray-to-gray matter disconnections revealed that disconnections of additional left-hemispheric areas (e.g., between the superior temporal gyrus and parietal areas) were significantly associated with the observed fact retrieval deficit. Results imply that disconnections of parietal areas (i.e., the AG) with language-related areas (i.e., superior and middle temporal gyri) seem specifically detrimental to arithmetic fact retrieval. This suggests that arithmetic fact retrieval recruits a widespread left-hemispheric network and emphasizes the relevance of white matter connectivity for number processing.

The spectacularly biodiverse Atlantic Forest of South America has been reduced to fragmented remnants. The largest remaining inland fragment is protected by national parks on either side of the iconic Iguassu Falls on the border between Brazil and Argentina. Biodiversity in the parks has been under pressure from illegal activities such as commercial hunting, fishing and extraction of palm hearts. A proposed road through Brazil’s Iguaçu National Park now further threatens the area’s biodiversity by further dividing the forest fragment and by increasing access by illegal actors. Here we analyze spatial data on illegal activities and develop a niche-based model to predict the impact of the proposed Caminho-do-Colono road. The model shows the significant increases that this road would provoke in susceptibility to illegal activities such as fishing (median 0.009 to 0.101), palm-heart extraction (median 0.087 to 0.260) and poaching (median 0.324 to 0.334). The road proposal includes downgrading the protected status of a portion of the park, which reflects a worldwide pattern of downsizing, downgrading and degazetting protected areas that is particularly evident in Brazil.

Phosphorus (P) is an essential nutrient for living organisms. Under P-limiting conditions plants and microorganisms can exude extracellular phosphatases that release inorganic phosphate (Pi) from organic phosphorus compounds (Porg). Phytic acid (myo-inositol hexakisphosphate, IP6) is an important form of Porg in many soils. The enzymatic hydrolysis of IP6 by phytase yields available Pi and less phosphorylated inositol derivates as products. The hydrolysis of organic P compounds by phosphatases leaves an isotopic imprint on the oxygen isotope composition (δ18O) of released Pi, which might be used to trace P in the environment. This study aims at determining the effect of phytase on the oxygen isotope composition of released Pi. For this purpose, enzymatic assays with histidine acid phytases from wheat and Aspergillus niger were prepared using IP6, adenosine 5'-monophosphate (AMP) and glycerophosphate (GPO4) as substrates. For a comparison to the δ18O of Pi released by other extracellular enzymes, enzymatic assays with acid phosphatases from potato and wheat germ with IP6 as a substrate were prepared. During the hydrolysis of IP6 by phytase, four of the six Pi were released, and one oxygen atom from water was incorporated into each Pi. This incorporation of oxygen from water into Pi was subject to an apparent inverse isotopic fractionation (ϵ ~ 6 to 10 ‰), which was similar to that imparted by acid phosphatase from potato during the hydrolysis of IP6 (ϵ ~ 7 ‰), where less than three Pi were released. The incorporation of oxygen from water into Pi during the hydrolysis of AMP and GPO4 by phytase yielded a normal isotopic fractionation (ϵ ~ −12 ‰), similar to values reported for acid phosphatases from potato and wheat germ. We attribute this similarity in ϵ to the same amino acid sequence motif (RHGXRXP) at the active site of these enzymes, which leads to similar reaction mechanisms. We suggest that the striking substrate dependency of the isotopic fractionation could be attributed to a difference in the δ18O values of the C–O–P bridging and non-bridging oxygen atoms in organic phosphate compounds.

High-precision U-Pb ion microprobe analyses provide new constraints on the emplacement and origin of the Kinabalu granite in Sabah, northern Borneo. The granite is a sheeted laccolith-like body comprising dyke-fed granitic units that young downwards, each emplaced beneath the previous sheet. Analyses of concentric growth zones in zircons indicate crystallization between 7.85±0.08 and 7.22±0.07 Ma, and show that the entire pluton was emplaced and crystallized within less than 800 ka. Several pulses of magmatism are recognized, each lasting for a maximum of 250 ka, and possibly as briefly as 30 ka. The oldest ages coincide with the highest elevations whereas the youngest ages are found at lower elevations around the edge of the body. Based on these new age data and field observations we identify the biotite granodiorite, hornblende granite and porphyritic facies as the Upper, Middle and Lower Units respectively. Inherited zircon ages indicate different protoliths for the Upper and Middle Units. The Upper Unit is derived from attenuated continental crust of the South China margin subducted beneath Sabah. The Middle Unit is sourced from melting of the crystalline basement in Sabah with little or no contribution from South China crust.

Thermochronological data from the Kinabalu granite, emplaced between c. 7.2 and 7.8 Ma, provide a unique record of northern Borneo\"s exhumation during the Neogene. Biotite 40Ar/39Ar ages (c. 7.32-7.63 Ma) record rapid cooling of the granite in the Late Miocene as it equilibrated with ambient crustal temperatures. Zircon fission-track ages (c. 6.6-5.8 Ma) and apatite (U-Th-Sm)/He ages (central age c. 5.5 Ma) indicate rapid cooling during the Late Miocene-Early Pliocene. This cooling reflects exhumation of the granite, uplift and erosion bringing it closer to the Earth\"s surface. Thermochronological age versus elevation relationships suggest exhumation rates of more than 7 mm a-1 during the latest Miocene and Early Pliocene. Neither the emplacement of the Kinabalu granite nor its exhumation is related to the Sabah orogeny, which terminated in the Early Miocene. Instead, granite magmatism was caused by extension related to subduction rollback of the Sulu Arc, and Mio-Pliocene exhumation of the Kinabalu granite was driven either by lithospheric delamination or break-off of a subducted slab beneath Sabah. Plio-Pleistocene tectonism offshore and onshore northern Borneo reflects continuing large-scale gravity-driven tectonics in the region.

Aim In this paper we aim to show that proportional sampling can detect species-area relationships (SARs) more effectively than uniform sampling. We tested the contribution of alpha and beta diversity in ant communities as explanations for the SAR. Location Tropical forest remnants in Viçosa, Minas Gerais, Brazil (20 °45' S, 42 °50' W). Methods We sampled 17 forest remnants with proportional sampling. To disentangle sampling effects from other mechanisms, species richness was fitted in a model with remnant size, number of samples (sampling effects) and an interaction term. Results A SAR was observed independent of the number of samples, discarding sampling effects. Alpha diversity was not influenced by remnant size, and beta diversity increased with remnant size; evidence to the fact that habitat diversity within remnants could be the dominant cause of the SAR. Such a relationship between beta diversity and remnant area may have also arisen due to the combined effects of territoriality and aggregation of ant species. Main conclusions The proposed model, together with proportional sampling, allowed the distinction between sampling effects and other mechanisms.

Two new species of the genus Eidmanacris are described (E. bidentata and E. corumbatai) and a new combination name (E. alboannulata) is assigned for the species Arachnomimus alboannulatus Piza, 1960 (= E. bicornis Mesa & Mello, 1985). Morphological and karyologycal information are provided, and the structure of the genital sclerites is discussed.

Dolomitic carbonate rock units from a variety of Phanerozoic localities and depositional environments throughout North America were evaluated with respect to their dolomite content and dolomite composition by X-ray diffraction analysis. Dolomite compositions range from 48 to 57 mole%$CaCO_{3}$with well-defined modes at 51% (nearly stoichiometric dolomite) and 55% (distinctly calcian dolomite)$CaCO_{3}$. Values of percentage of dolomite also exhibit a pronounced, albeit less well-defined, bimodal distribution with modes at 97% (dolostones) and 20% (dolomitic limestones) dolomite. Similar distributions characterize most other published data on Phanerozoic dolomitic carbonates. These data suggest that two separate processes may lead to two distinct populations of sedimentary dolomite: (1) dolomitic limestones originate in diagenetically closed systems during magnesian calcite dissolution-calcite and dolomite precipitation reactions, and (2) dolostones originate in diagenetically open systems during the dissolution of calcium carbonate precursors in the presence of allochthonous magnesium ions. In addition, these data document a genetic relationship between amount of dolomite and dolomite composition. Particularly in Paleozoic sequences, most dolostones consist of stoichiometric dolomite whereas most dolomitic limestones contain rhombs of calcian dolomite. This relationship suggests: (1) at the time of their formation, many ancient marine micrites contained appreciable amounts of magnesian calcite, and therefore an internal supply of magnesium for dolomite formation, (2) although calcian dolomite is metastable, in closed diagenetic systems it is non-reactive, and (3) the presence of calcian dolomite in limestones may serve as a useful criterion in the evaluation of rock/water ratios during the diagenetic stabilization of carbonate sequences.

There are several factors that may affect sampling with pitfall traps. Here we test the hypothesis that the mere walking of the researcher proximate to the traps could cause an increment in the capture of crickets. This would occur if the walking provoked vibration in the litter, to which crickets showed a jumping response, thus falling into the pitfall traps. We mounted 126 traps in 14 groups of nine. The traps within a group were positioned in three parallel rows of three traps each, one meter apart from each other. Each group of nine traps was separated from the other groups by at least 5 m. Each group of nine traps was submitted to one of seven levels of disturbance frequency. Exposure time was 7 d for all traps. Treatments (disturbance frequencies) were allocated randomly among trap groups. For the data analyses we adjusted mixed-effects polynomial models. We captured 723 cricket individuals, distributed in 10 genera, most in the nymphal stage. As expected, the number of captured individuals, as well as the number of genera, increased with disturbance frequency. However this response was not linear: at higher disturbance frequencies there was a decrease in captures. There was also an effect of trap positioning within each group: central traps were more affected by disturbance than peripheral ones, while peripheral traps captured more individuals and genera in the absence of disturbance. Therefore we recommend areas near pitfall traps not be visited during the trapping period. Alternatively, to enhance sampling efficiency, the researcher may do programmed visiting to the trapping area, but this must be rigorously designed to provoke exactly the same disturbance for all traps. Enhancing the distance among traps will augment efficiency in capturing individuals and capture larger cricket diversity. Further studies of the interaction between methodology and cricket behavior will refine our ability to design and interpret pitfall studies.

Arithmetic fact retrieval has been suggested to recruit a left-lateralized network comprising perisylvian language areas, parietal areas such as the angular gyrus (AG), and subcortical structures such as the hippocampus. However, the underlying white matter connectivity of these areas has not been evaluated systematically so far. Using simple multiplication problems, we evaluated how disconnections in parietal brain areas affected arithmetic fact retrieval following stroke. We derived disconnectivity measures by jointly considering data from n=73 patients with acute unilateral lesions in either hemisphere and a white-matter tractography atlas (HCP-842) using the Lesion Quantification Toolbox (LQT). Whole-brain voxel-based analysis indicated a left-hemispheric cluster of white matter fibers connecting the AG and superior temporal areas to be associated with a fact retrieval deficit. Subsequent analyses of direct grey-to-grey matter disconnections revealed that disconnections of additional left-hemispheric areas (e.g., between the superior temporal gyrus and parietal areas) were significantly associated with the observed fact retrieval deficit. Results imply that disconnections of parietal areas (i.e., the AG) with language-related areas (i.e., superior and middle temporal gyri) seem specifically detrimental to arithmetic fact retrieval. This suggests that arithmetic fact retrieval recruits a widespread left-hemispheric network and emphasizes the relevance of white matter connectivity for number processing.