Global maps of soil temperature

Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0-5 and 5-15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications.

Depth Illusion by Delayed 3-D Perception (‘Delayed Stereopsis Illusion’): A Novel Way to Determine Computation Times in Human Vision by Depth Reversal in Partially Occluded Moving Objects

Viewed through depth-reversing spectacles, nontransparent objects appear to cut ‘gaps’ into a patterned background. In moving objects this gap is seen to extend beyond the occluded area (‘delayed stereopsis illusion’, DSI): Its trailing border appears to lag behind by a precisely measurable distance, indicating a processing time of approximately 0.13 s to accomplish stereopsis [cf Morgan and Castet, 1995 Nature (London)378 380 – 383]. Other than in thigmaesthesia, there is no correction by antedating.

Why is this delay not perceived in normal stereopsis? If an object is moving before some background, the background usually maintains its position; it may be occluded, or not. Depth information thus might be extrapolated to the continuously uncovered regions of the patterned background. Depth reversal demands that the occluded region of the background must jump behind the moving, occluding object. As this object is perceived to retain its distance, the background, as it is getting uncovered, must jump back into the foreground, where it can be perceived only after renewed calculation of binocular depth. The dependence of DSI on eye movements, disparity, velocity, motion direction, surface texture, illuminance, spatial frequency, and fractal dimension of the objects involved is currently being investigated in model systems which allow us to determine processing times of human stereopsis under well-defined conditions.

A comprehensive immunotopographic map of human thymus

We have achieved a comprehensive immunotopographic mapping of human thymus by using a large battery of monoclonal antibodies and the methodological refinement of comparative serial tissue section immunohistochemistry, allowing analysis of multiple phenotypes in the same tissue site. Previous immunohistochemical studies of thymus have concentrated on the majority T-cell and epithelial cell populations. Besides demonstrating the complexity of T-cell antigenic expression (e.g., simultaneous cortical expression of Leu 2, Leu 3, CALLA, Tdt, and Leu 6), we delineate surprisingly complex B-cell zones (e.g., septal B-follicles with DRC+C3d+ dendritic cells and zonal maturation of B-cells). Whereas septal B-follicles were found in 25% of cases, medullary B-cells were universally present as a substantial minority component. This expanded immunotopographic knowledge of the complex T-, B-, epithelial, and reticulum cell neighborhoods suggests that the thymus is an organ capable of a broad repertoire of immunological responses, not limited to T-cell development.

The immunoarchitecture of cutaneous pseudolymphoma

The immunoarchitecture of five cutaneous pseudolymphomas was studied by staining serial sections for T- and B-cell and dendritic reticulum cell (DRC) antigens with monoclonal antibodies, and compared with that of reactive lymph nodes and cutaneous lymphoma. In four cases compartmentalization of B and T cells was observed, analogous to findings in reactive lymph nodes. In two of these cases the immunoarchitectural features were strikingly similar to those of reactive lymph nodes. Both had distinct follicles with germinal centers, and in one distinct mantle zone formation was seen. B cells in the follicles were polyclonal, with kappa chain predominance. The germinal centers showed the expected intercellular and/or dendritic pattern of immunoglobulin heavy chain, B2, and DRC-antigen expression. T cells admixed in the germinal centers were overwhelmingly of the T-helper type. The B-cell compartments in the other two cases showed some subtle immunologic evidence of aberrance, but the weight of evidence suggested reactive/aberrant rather than malignant processes. The T-cell compartments in all four cases showed a predominance of T-helper and a minority of T-suppressor/cytotoxic cells. All contrasted with the lymphomas, which showed B-cell monoclonality, markedly deranged T-subset proportions, or novel T-cell phenotypes. Although the main focus of this study was cases involving substantial populations of both B and T cells, preliminary observations were made in one case in which a predominance of T cells and prominent epidermotropism simulated mycosis fungoides. Quantitative ultrastructural analysis in this case suggested a reactive T-cell process. Leu-6-positive Langerhans cells were increased in the epidermis and dermis in all five cases, and in the dermis they were found almost exclusively in T-cell compartments. It is proposed that this distribution is the anatomic correlate to the known functional role of Langerhans cells in antigen processing/presentation and T-cell activation. In the cutaneous "lymph node equivalent," Langerhans cells are analogous to interdigitating reticulum cells of reactive lymph nodes in distribution and, probably, in function. The DRC found in the germinal centers in two cases were probably antigenically identical and functionally analogous to those in germinal centers of reactive lymph nodes. Immunologic phenotyping of serial cutaneous sections may aid in distinguishing reactive from neoplastic lymphoid lesions. Immunoarchitectural analysis promises to be a powerful tool for the study of lymphoproliferative disease.

The probable origin of an anemone cell tumor: metastatic transitional cell carcinoma producing HCG

A neoplasm of unknown origin in cervical and axillary lymph nodes was diagnosed as anemone cell tumor by ultrastructural examination. Three years after the initial diagnosis of anemone cell tumor, a high-grade transitional cell carcinoma of the bladder was discovered. The results of immunoperoxidase staining of the cervical lymph node, axillary lymph node, and bladder tumors for keratin, carcinoembryonic antigen, and human chorionic gonadotropin (HCG) strongly suggest that the anemone cell tumors in this case represent metastases of bladder carcinoma cells capable of producing HCG.