Remotely sensed data can help to identify both suitable habitat for individual species, and environmental conditions that foster species richness, which is important when predicting how biodiversity ...will respond to global change. The question is how to summarize remotely sensed data so that they are most relevant for biodiversity analyses, and the Dynamic Habitat Indices are three metrics designed for this. Our goals here were to a) derive, for the first time, the Dynamic Habitat Indices (DHIs) globally, and b) use these to evaluate three hypotheses (available energy, environmental stress, and environmental stability) that attempt to explain global variation in species richness of amphibians, birds, and mammals. The three DHIs summarize three key measures of vegetative productivity: a) annual cumulative productivity, which we used to evaluate the available energy hypothesis that more energy is associate with higher species richness; b) minimum productivity throughout the year, which we used to evaluate the environmental stress hypothesis that higher minima cause higher species richness, and c) seasonality, expressed as the annual coefficient of variation in productivity, which we used to evaluate the environmental stability hypothesis that less intra-annual variability causes higher species richness. We calculated the DHIs globally at 1-km resolution from MODIS vegetation products (NDVI, EVI, LAI, fPAR, and GPP), based on the median of the good observations of all years from the entire MODIS record for each of the 23 or 46 possible dates (8- vs. 16-day composites) during the year, and calculated species richness for three taxa (amphibians, birds, and mammals) at 110-km resolution from species range maps from the IUCN Red List. We found marked global patterns of the DHIs, and strong support for all three hypotheses. The three DHIs for a given vegetation product were well correlated (Spearman rank correlations ranging from −0.6 (cumulative vs. variation DHIs) to −0.93 (variation vs. minimum DHI)). Similarly, DHI components derived from different MODIS vegetation products were well correlated (0.8–0.9), and correlations of the DHIs with temperature and precipitation were moderate and strong respectively. All three DHIs were well correlated with species richness, showing in ranked order positive correlations for cumulative DHI based on GPP (Spearman rank correlations of 0.75, 0.63, and 0.67 for amphibians, resident birds, and mammals respectively) and minimum DHI (0.73, 0.83, and 0.62), and negative for variation DHI (−0.69, −0.83, and −0.59). Multiple linear models of all three DHIs explained 67%, 65%, and 61% of the variability in species richness of amphibians, resident birds, and mammals, respectively. The DHIs, which are closely related to well-established ecological hypotheses of biodiversity, can predict species richness well, and are promising for application in biodiversity science and conservation.
•The Dynamic Habitat Indices (DHIs) capture three aspects of annual productivity.•We derived DHIs from all MODIS vegetation products globally at 1-km resolution.•Cumulative, minimum, and variation DHIs all correlate well with species richness.•Relationships between species richness and the DHIs support ecological theory.•Amphibians and birds are best explained by DHIs, mammals least.
Anecdotal evidence suggests that socioeconomic shocks strongly affect wildlife populations, but quantitative evidence is sparse. The collapse of socialism in Russia in 1991 caused a major ...socioeconomic shock, including a sharp increase in poverty. We analyzed population trends of 8 large mammals in Russia from 1981 to 2010 (i.e., before and after the collapse). We hypothesized that the collapse would first cause population declines, primarily due to overexploitation, and then population increases due to adaptation of wildlife to new environments following the collapse. The long‐term Database of the Russian Federal Agency of Game Mammal Monitoring, consisting of up to 50,000 transects that are monitored annually, provided an exceptional data set for investigating these population trends. Three species showed strong declines in population growth rates in the decade following the collapse, while grey wolf (Canis lupus) increased by more than 150%. After 2000 some trends reversed. For example, roe deer (Capreolus spp.) abundance in 2010 was the highest of any period in our study. Likely reasons for the population declines in the 1990s include poaching and the erosion of wildlife protection enforcement. The rapid increase of the grey wolf populations is likely due to the cessation of governmental population control. In general, the widespread declines in wildlife populations after the collapse of the Soviet Union highlight the magnitude of the effects that socioeconomic shocks can have on wildlife populations and the possible need for special conservation efforts during such times.
The absorption of multiple photons when there is no resonant intermediate state is a well-known nonlinear process in atomic vapours, dyes and semiconductors. The N-photon absorption (NPA) rate for ...donors in semiconductors scales proportionally from hydrogenic atoms in vacuum with the dielectric constant and inversely with the effective mass, factors that carry exponents 6N and 4N, respectively, suggesting that extremely large enhancements are possible. We observed 1PA, 2PA and 3PA in Si:P with a terahertz free-electron laser. The 2PA coefficient for 1s–2s at 4.25 THz was 400,000,000 GM (=4 × 10−42 cm4 s), many orders of magnitude larger than is available in other systems. Such high cross-sections allow us to enter a regime where the NPA cross-section exceeds that of 1PA—that is, when the intensity approaches the binding energy per Bohr radius squared divided by the uncertainty time (only 3.84 MW cm−2 in silicon)—and will enable new kinds of terahertz quantum control.
SUMMARY
Visceral obesity and metabolic syndrome (MetSyn) represent a constellation of inflammation, insulin resistance, and hyperglycemia and are established risk factors for gastrointestinal cancer. ...However, their impact on the immune and inflammatory response after major upper gastrointestinal oncologic surgery is unknown. In 125 consecutive patients who underwent esophagectomy, C-reactive protein (CRP) and CRP:albumin levels were recorded preoperatively and on days 1, 3, 7, and 14 postoperatively. In a subset of 30 patients, circulating levels of IL-6, IL-8, IL-10, IL-12p70, IFN-γ, TNF-α, TGF-β, and cortisol were measured. Incidences of postoperative complications were prospectively recorded. In the study cohort, 51% of patients were viscerally obese, 40.7% had MetSyn, and 33.6% were hyperglycemic. Viscerally obese and MetSyn-positive patients demonstrated greater postoperative CRP levels and CRP:albumin levels on day 7 and day 14 compared with nonobese and MetSyn-negative patients (P < 0.05). Higher postoperative circulating levels of cortisol were observed in the viscerally obese and hyperglycemic patients compared to nonobese and normoglycemic patients. No association was observed between visceral obesity, MetSyn or hyperglycemia, and postoperative cytokine profile. Viscerally obese patients had an increased overall incidence of postoperative complications compared to nonobese patients (67.2% vs. 47.5%, P = 0.031) on univariate but not multivariate analysis (P = 0.078) and visceral obesity was not associated with an increased incidence of specific complications. Visceral obesity, MetSyn, and hyperglycemia are prevalent in patients undergoing major upper gastrointestinal resection and are associated with an exaggerated acute-phase inflammatory response postoperatively. Further research is warranted to determine whether this association is directly causal.
•We studied a loss of protected forest before and after the collapse of the USSR.•In our study area, the Western Caucasus, clear cut rate was notably low.•The biggest forest loss hotspot was ...associated with the 2014 Olympic Winter Games.
Economic and social transition periods can have strong negative effects for the environment and for wildlife. The collapse of the Soviet Union in 1991 provides a striking example of social turmoil and transition to a new society. It is unclear, however, how humans affected the environment in the course of the collapse, and if institutions designed to safeguard the environment continued to fulfill their intended role. Our goal was to assess the impact of the collapse of the Soviet Union on forest canopy removal rates in protected areas, and how these rates varied by protected area status and over time. We monitored forest canopy removal within and outside of protected areas using a 1985–2010 time series of Landsat satellite images from the Western Caucasus. On average, we found surprisingly low annual forest canopy removal rates of only 0.03%. The highest canopy removal inside of protected areas of all types occurred after 2000. Among the protected areas, we found the highest canopy removal rates within Sochi National Park, attributable to construction for the Olympic Games and in spite of the Park’s protected status. Overall, it is encouraging that forest canopy removal rates in protected areas in the Western Caucasus are far lower than in other Russian regions. Because many local endemic plant and animal species are found in the Caucasus region, clear cuts are prohibited, and this regulation appears to be effective. However, forest canopy removal within protected areas caused by major social and political events such as the Olympic Games is of concern.
One of the great successes of quantum physics is the description of the long-lived Rydberg states of atoms and ions. The Bohr model is equally applicable to donor impurity atoms in semiconductor ...physics, where the conduction band corresponds to the vacuum, and the loosely bound electron orbiting a singly charged core has a hydrogen-like spectrum according to the usual Bohr-Sommerfeld formula, shifted to the far-infrared because of the small effective mass and high dielectric constant. Manipulation of Rydberg states in free atoms and ions by single and multiphoton processes has been tremendously productive since the development of pulsed visible laser spectroscopy. The analogous manipulations have not been conducted for donor impurities in silicon. Here, we use the FELIX pulsed free electron laser to perform time-domain measurements of the Rydberg state dynamics in phosphorus- and arsenic-doped silicon and we have obtained lifetimes consistent with frequency domain linewidths for isotopically purified silicon. This implies that the dominant decoherence mechanism for excited Rydberg states is lifetime broadening, just as for atoms in ion traps. The experiments are important because they represent a step toward coherent control and manipulation of atomic-like quantum levels in the most common semiconductor and complement magnetic resonance experiments in the literature, which show extraordinarily long spin lattice relaxation times--key to many well known schemes for quantum computing qubits--for the same impurities. Our results, taken together with the magnetic resonance data and progress in precise placement of single impurities, suggest that doped silicon, the basis for modern microelectronics, is also a model ion trap.
Background and purpose
Intracranial haemorrhage in neurosarcoidosis (NS‐ICH) is rare, poorly understood and the diagnosis of NS may not be immediately apparent.
Methods
The clinical features of three ...new NS‐ICH cases are described including new neuropathological findings and collated with cases from a systematic literature review.
Results
Cases: (i) A 41‐year‐old man with headaches, hypoandrogenism and encephalopathy developed a cerebellar haemorrhage. He had neuropathological confirmation of NS with biopsy‐proven angiocentric granulomata and venous disruption. He responded to immunosuppressive therapy. (ii) A 41‐year‐old man with no history of hypertension was found unconscious. A subsequently fatal pontine haemorrhage was diagnosed. Liver biopsy revealed sarcoid granulomas. (iii) A 36‐year‐old man with raised intracranial pressure headaches presented with a seizure and a frontal haemorrhage. Hilar lymph node biopsy confirmed sarcoidosis, and he was treated successfully. Systematic review: Twelve other published cases were identified and collated with our cases. Average age was 36 years and M:F = 2.3:1; 46% presented with neurological symptoms and 31% had CNS‐isolated disease. Immediate symptoms of ICH were acute/worsening headache or seizures (60%). ICH was supratentorial (62%), infratentorial (31%) or subarachnoid (7%). Forty percent had definite NS, 53% probable NS and 7% possible NS (Zajicek criteria). Antigranulomatous/immunosuppressive therapy regimens varied and 31% died.
Conclusions
This series expands our knowledge of the pathology of NS‐ICH, which may be of arterial or venous origin. One‐third have isolated NS. Clinicians should consider NS in young‐onset ICH because early aggressive antigranulomatous therapy may improve outcome.
Helicobacter pylori infection is the major cause of peptic ulceration and gastric adenocarcinoma. To address the hypothesis that the human acquired immune response to H. pylori influences ...pathogenesis, we characterised the gastric T helper (Th) and regulatory T cell (Treg) response of infected patients.
The human gastric CD4(+) T cell response of 28 donors who were infected with H. pylori and 44 who were not infected was analysed using flow cytometry. The T cell associated mucosal cytokine response was analysed by real-time polymerase chain reaction assay of samples from 38 infected and 22 uninfected donors. Recombinant interleukin 10 (IL10) was added to co-cultures of H. pylori and AGS cells and its suppressive effects upon inflammatory responses were measured.
We found that the H. pylori-specific response consists of both T helper 1 and 2 subsets with high levels of IL10-secreting Tregs. People with peptic ulcer disease had a 2.4-fold reduced CD4(+)CD25(hi)IL10(+) Treg response (p = 0.05) but increased Th1 and Th2 responses (Th1: 3.2-fold, p = 0.038; Th2: 6.1-fold, p = 0.029) compared to those without ulcers. In vitro studies showed that IL10 inhibited IL8 expression and activation of nuclear factor kappa B induced by H. pylori in gastric epithelial cells, and enhanced H. pylori growth in a bacterial-cell co-culture model.
Together our data suggest that H. pylori induces a regulatory T cell response, possibly contributing to its peaceful coexistence with the human host, and that ulcers occur when this regulatory response is inadequate.
Animals select habitat at multiple spatial scales, suggesting that biodiversity modeling, for example of species richness, should be based on environmental data gathered at multiple spatial scales, ...and especially multiple grain sizes. Different satellite sensors collect data at different spatial resolutions and therefore provide opportunities for multi-grain habitat measures. The dynamic habitat indices (DHIs), which are derived from satellite data, capture patterns of vegetative productivity and predict bird species richness well. However, the DHIs have only been analyzed at single resolutions (e.g., 1-km), and have not yet been derived from high-resolution satellite data (< 10 -m). Our goal was to predict bird species richness based on measures of vegetation productivity (DHIs, NDVI median and NDVI percentile 90th) across a range of spatial resolutions both from different sensors, and from resampled high-resolution imagery. We analyzed bird species richness within 215 forest, grassland and shrubland plots (56.25 ha) located at 26 terrestrial field sites of the National Ecology Observatory Network (NEON), in the continental US. To obtain our multi-resolution measures of vegetation productivity, we acquired data from Planetscope (3-m), RapidEye (5-m), Sentinel-2 (10-m), Landsat-8 (30-m) and MODIS (250-m) from 2017 to 2020, generated time series of NDVI, calculated the three DHIs (cumulative, minimum and variation), NDVI median and the 90th percentile NDVI and calculated 1st and 2nd order texture measures. We evaluated the performance of the derived measures to predict bird species richness of habitat specialist guilds based on (i) univariate models (ii) multivariate models with single-resolution measures and (iii) multivariate models with multi-resolution measures. Single-spatial resolution measures predicted bird species richness moderately well (R2 up to 0.51) and the best performing spatial resolution and measure differed among bird species guilds. High-spatial resolution (3–5 m) measures outperformed medium-resolution measures (10–250 m). Models for all guilds performed best when incorporating multiple resolutions, including for all species richness (R2 = 0.63) and for forest (R2 = 0.72), grassland (R2 = 0.53) and shrubland specialists (R2 = 0.46). In addition, models based on multi-resolution data from different sensors performed better than models based on resampled high-resolution data for any of the guilds. Our results highlight, first, the value of the DHIs derived from high-resolution satellite data to predict bird species richness and, second, that remotely-sensed vegetation productivity measures from multiple spatial resolutions offer great promise for quantifying biodiversity.
•Single-spatial resolution measures predicted bird richness moderately well.•Best-performing spatial resolution and measure differed among bird species guilds.•High-resolution measures performed better than medium-resolution measures.•Multi-grain habitat models performed best for all bird species guilds.•Models based on original data performed better than resampled data models.
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