Small Size Range Research Articles

Electrosprayed extracellular matrix nanoparticles induce a pro‐regenerative cell response

Decellularized extracellular matrix (ECM) is an effective tissue repair scaffold. Additionally, ECM has recently been shown to be protective to the lungs. However, current processing is inadequate for effective delivery of ECM to the lungs. Processing methods, such as milling, produce large variability in particle sizes. The size variation produced is ineffective at treating the lung because only a small range of sizes reach the distal regions of the alveoli. The aim of this work is to formulate decellularized ECM to reach the distal lung while retaining the pro-regenerative effects of ECM. We first digested the protein in acid and then electrosprayed the solution into nanoparticles. The average size of the nanoparticles was 225 (±67)nm, within size requirements to reach the alveoli. After characterizing the particles, we measured cytotoxicity of the nanoparticles. Adding 0.125mg/ml of nanoparticles to the media increased cellular proliferation in A549 alveolar epithelial cells and caused no cytotoxicity in BEAS-2B cells. We added the formed nanoparticles to macrophages derived from murine bone marrow-derived monocytes. The macrophages exposed to the formed nanoparticles expressed cell surface marker CD206 (mannose receptor C type 1), commonly attributed to a pro-regeneration phenotype. Electrosprayed ECM formed nanoparticles may improve bronchoalveolar deposition while maintaining the pro-regenerative benefits shown by other decellularized ECM materials.

Facets of phylodiversity: evolutionary diversification, divergence and survival as conservation targets.

Biodiversity is often described as having multiple facets, including species richness, functional diversity and phylogenetic diversity. In this paper, we argue that phylogenetic diversity itself has three distinct facets-lineage diversification, character divergence and survival time-that can be quantified using distinct branch length metrics on an evolutionary tree. Each dimension is related to different processes of macroevolution, has different spatial patterns and is tied to distinct goals for conserving biodiversity and protecting its future resilience and evolutionary potential. We compared the landscapes identified as top conservation priorities by each of these three metrics in a conservation gap analysis for California, a world biodiversity hotspot, using herbarium data on the biogeography and evolutionary relationships of more than 5000 native plant species. Our analysis incorporated a novel continuous metric of current land protection status, fine-scale data on landscape intactness and an optimization algorithm used to identify complementary priority sites containing concentrations of taxa that are evolutionarily unique, vulnerable due to small range size and/or poorly protected across their ranges. Top conservation priorities included pockets of coastal and northern California that ranked highly for all three phylodiversity dimensions and for species richness, as well as sites uniquely identified by each metric whose value may depend on whether properties such as genetic divergence, high net diversification or independent survival experience are most desirable in an Anthropocene flora.This article is part of the theme issue 'Biological collections for understanding biodiversity in the Anthropocene'.

Functional and geographic components of risk for climate sensitive vertebrates in the Pacific Northwest, USA

Rarity and life history traits inform multiple dimensions of intrinsic risk to climate and environmental change and can help systematically identify at-risk species. We quantified relative geographic rarity (area of occupancy), climate niche breadth, and life history traits for 114 freshwater fishes, amphibians, and reptiles in the U.S. Pacific Northwest. Our approach leveraged presence-only, publicly available data and traits-based inference to evaluate area of occupancy, climate sensitivity (i.e., climate niche breadth), and a Rarity and Climate Sensitivity (RCS) index of all species across multiple geographic extents, grain sizes, and data types. The RCS index was relatively stable across extents, grains, and data types, with climate sensitivity differentiating species with otherwise similar areas of occupancy. We also found that species with sensitivity-associated traits (e.g., long generation time, low fecundity) were not necessarily the same species identified as at-risk with geographical approaches (small range size, small climate niche breadth). Many multispecies assessments using coarse-scale data (e.g., entire range maps or convex-hull approaches) often focus on a single dimension of intrinsic risk; others rely on data-intensive models only applicable to a few well-studied species. What remains is a need for an approach that enables multispecies, multidimensional assessment efforts. This is particularly true at regional scales, where management needs require assessments that are intermediate to coarse- and fine-scale approaches. We demonstrate that by considering multiple dimensions of intrinsic risk to climate change (range size, climate sensitivity, and traits), site-specific locality data may offer a pathway for ensuring vulnerable, understudied species do not go overlooked in conservation.

Population density and annual and seasonal space use by feral cats in an exurban area

Feral cats (Felis catus) exhibit contrasting behavior in urban and rural areas. Urban cats form dense social groups with small home range sizes while feral cats occupying rural areas are typically solitary and inhabit larger home ranges. Because feral cat behavior is influenced by their surroundings and exurban areas possess components of both urban and rural areas, it is expected that feral cats in exurban areas will demonstrate an intermediate behavior pattern. Given that feral cat ecology is understudied in exurban areas, our objectives were to estimate feral cat density, quantify annual and seasonal home range areas, and characterize macrohabitat use among annual and seasonal home ranges of feral cats within the exurban city of Russellville, Arkansas during October 2012–December 2013. In our study, home ranges of male feral cats (29.17 ± 7.70 ha) were larger than female home ranges (12.26 ± 2.90 ha), but the size of core areas did not differ by sex. Feral cats in Russellville disproportionately used developed areas and pasture and hay fields more than other habitats within the exurban matrix. Feral cat density in Russellville was found to be relatively low (0.10 cats/ha) and although home ranges (19.76 ± 4.28 ha) were similar to rural feral cat populations, areas of core use (3.73 ± 0.95 ha) were similar to urban and suburban living cats. Therefore, this exurban feral cat population appears to share characteristics with both rural and urban feral cat populations.

Comparison of Repair Costs for Small and Mid-Sizes Farm Machinery in Malaysian Oil Palm Plantation

Farm machinery has been tremendously used to perform laborious tasks and speed-up the in-field operations in Malaysian oil palm plantation. In line with significant increase in farm machinery usage in Malaysian oil palm plantation, hence, repair costs of farm machinery should be well-managed. Failure to do so may result the plantations profits will be affected. This study aims to analyze and compare the current data of repair costs for small and mid-sizes farm machinery that are commonly used in Malaysian oil palm plantation. Besides, this study also aims to update and adapt the values of repair factors for cumulative repair and maintenance (Crm) costs model of farm machinery in Malaysian oil palm plantation. The relevant data were collected through a survey that was carried out at several oil palm plantations in Melaka and Negeri Sembilan states of Malaysia. The findings indicated the common sizes of farm machinery used Malaysian oil palm plantation were in range of small-size (28HP) to mid-size (75HP). It was found that annual average repair costs of mid-size farm machinery was 60.08% higher than the small-size one. Meanwhile, mean ages of mid-size farm machinery was also 80.7 % longer than the small-size one. The values of repairs factors 1 (RF1) and repairs factor 2 (RF2) for cumulative repair and maintenance costs model (Crm) of farm machinery in Malaysian oil palm plantation were 1.4061 and 1.6588, respectively. Conclusively, the findings of study can give a valuable contribution to the oil palm plantations management in developing their strategic planning concerning to the allocation of overall costs of farm machinery.

A novel method of preparing Ti powder for 3D printing

PurposeThe purpose of this paper is to propose a novel method to prepare pure Ti powder for 3D printing with tailorable particle size distribution.Design/methodology/approachThe main procedures of the present method consist of gas state reaction to synthesize TiH2 nanoparticles, agglomeration to obtain micronscale powder particles by spray drying, and densification of particle interior by heat treatment.FindingsThe prepared Ti powder has a specific bimodal particle size distribution in a range of small sizes, good sphericity and high flowability. Particularly, this new technique is capable of controlling powder purity and adjusting particle size.Originality/valueTo the best knowledge of the authors, the approach for preparing 3D printing metallic powders from nanoparticles has not been reported in the literature so far. This work provides a novel method that is particularly applicable to prepare 3D printing metallic powders which have small initial particle sizes and high reactivity in the air.

MLC positioning verification for small fields: a new investigation into automatic EPID-based verification methods.

Multileaf-collimator (MLC) defined small fields in radiotherapy are used in high dose, ultra-conformal techniques such as stereotactic radiotherapy and stereotactic radiosurgery. Proximity to critical structures and irreversible damage arising from inaccurate delivery mean that correct positioning of the MLC system is of the utmost importance. Some of the existing techniques for MLC positioning quality assurance make use of electronic portal imaging device (EPID) images. However, conventional collimation verification algorithms based on the full width at half maximum (FWHM) fail when applied to small field images acquired by an EPID due to overlapping aperture penumbrae, lateral electron disequilibrium and radiation source occlusion. The objective of this study was to investigate sub-pixel edge detection and other techniques with the aim of developing an automatic and autonomous EPID-based method suitable for MLC positional verification of small static fields with arbitrary shapes. Methods investigated included derivative interpolation, Laplacian of Gaussian (LoG) and an algorithm based on the partial area effect hypothesis. None of these methods were found to be suitable for MLC positioning verification in small field conditions. A method is proposed which uses a manufacturer-specific empirically modified FWHM algorithm which shows improvement over the conventional techniques in the small field size range. With a measured mean absolute difference from planned position for Varian linacs of 0.01 ± 0.26mm, compared with the erroneous FWHM value of 0.70 ± 0.51mm. For Elekta linacs the proposed algorithm returned 0.26 ± 0.25mm, in contrast to the FWHM result of 1.79 ± 1.07mm.

Size tunable biosynthesis and luminescence quenching of nanostructured hematite (α-Fe2O3) for catalytic degradation of organic pollutants

In the present study, an environmentally benign protocol has been proposed for surfactant-free and template-free aqueous biosynthesis of hematite nanoparticles without complicated heat treatment procedures. Nanostructured hematite of different sizes has been synthesized, exploiting the capping potential of polyphenolic tannin rich leaf broth of Psidium guajava plant, by optimizing the precursor concentration and quantity of broth. The synthesized nanostructures are characterized by XRD, SEM, TEM, HRTEM, EDX and FTIR techniques to confirm their phase purity, size distribution and chemical environment. In order to determine the proper annealing temperature, thermal analysis of the as synthesized product has been carried out. The absorption and reflection characteristics of the nanoparticles in the UV–vis-IR region confirm the existence of energy band gap of 2.1 eV in the samples. Magnetic characteristics of the samples have been investigated using Vibrating Sample Magnetometer to show weak ferromagnetism at room temperature, tendency of a superparamagnetic behavior at lower temperatures and size dependent coercivity and saturation magnetization. The relatively small difference between the irreversibility temperature and blocking temperature observed in FC and ZFC curves supports the fact that the nanoparticles are distributed in a small size range, which is in agreement with SEM and TEM result. The synthesized nanoparticles are found to show luminescent emission in the visible region at 575 nm on excitation by a wavelength of 384 nm. The capping of acidic tannin molecules could effectively quench the luminescence of the synthesized particles, thereby enhancing their catalytic efficiency. The biosynthesized nanoparticles could effectively catalyse degradation of the organic pollutants methyl red, methyl orange, eosin yellowish and methylene blue which recommends the possible application in the treatment of industrial waste water.

Oxypetalum marchesii (Apocynaceae, Asclepiadoideae), an Endemic New Species from Uruguay

Fil: Gonzalez, Andres. Museo Nacional de Historia Natural. Departamento de Botanica; Uruguay

Evaporation From Confined Porous Media Due to Controlled IR Heating From Above

We report an experimental study of evaporation due to controlled infrared (IR) heating from above from an initially saturated confined porous medium consisting of nearly ‘mono-disperse’ particles which has been rarely used earlier. We have used three diagnostic tools simultaneously, evaporation rate measurements using a precision weighing balance, surface temperature measurements using IR imaging, and fluorescein dye mixed with water to visualize the drying front and the evaporation sites. IR images show that the first stage, so-called constant rate period (CRP), was maintained due to films of water reaching the top surface from the saturated region below. Gradually reducing evaporation rate in stage 1 is shown to be related to ‘shrinking evaporating patches’ on the top surface, clearly revealed as lower-temperature regions in the IR images. End of CRP coincides with disappearance of the low-temperature patches. We give end of CRP in terms of the average depth (Lcap) of the liquid level from the top surface at that time. Lcap and duration of CRP are strong functions of the porous medium bead size, transition to stage 2 happening earlier for coarser spheres. The obtained Lcap values deviated from the predictions of Lehmann et al. (Phys Rev E 77(5):056309, 2008) which we show is due to a small range of pore sizes in the current experiments. For both water and highly volatile n-pentane, we show that Lcap normalized by a length scale derived from gravity-surface tension force balance goes like Bo0.20, for Bo varying from 2.0E − 04 to 1.0E − 01; Bo is the Bond number. Fluorescein dye imaging shows a different view of the evaporation stages. During CRP, highly concentrated deposits of the fluorescein dye particles, orange in colour, are seen in the top few bead layers. These orange deposits represent the sites on the beads surfaces where the evaporation has taken place. Even with external heating, evaporation from such a porous medium is limited to a finite depth from the evaporating end, similar to the observation by Lehmann et al. (2008) for isothermal evaporation in Hele-Shaw cell.

Cortical and subcortical changes in patients with premenstrual syndrome

BackgroundPremenstrual syndrome (PMS) is characterized by a series of emotional, physical and behavioral symptoms. Although PMS is related to dysfunctions of the central nervous system, the neuropathological mechanism of PMS still has not been clearly established. The aim of this study is to evaluate potential differences in both cortical thickness and subcortical volumes in PMS patients compared to healthy controls (HCs). MethodsTwenty PMS patients and twenty HCs underwent a structural magnetic resonance imaging scan and clinical assessment. Cortical thickness and subcortical volumes were computed using the FreeSurfer image analysis suite. Relationships between cortical thickness/subcortical volumes and the daily rating of severity of problems (DRSP) score were then measured in patients. ResultsCompared to HCs, PMS patients exhibited reduced cortical thickness in the medial prefrontal cortex (MPFC), orbitofrontal cortex (OFC) and insula, and increased subcortical volumes of the amygdala, thalamus and pallidum. Furthermore, negative correlations were detected between the DRSP and cortical thickness in the anterior cingulate cortex and precuneus. LimitationsThe study is limited by a small sample size and narrow age range of participants. ConclusionsOur findings indicate that the abnormal morphological changes are mainly implicated in emotional regulation and visceral perception in PMS patients. We hope that our study may contribute to a better understanding of PMS.

Home range of raccoon dogs in an urban green area of Tokyo, Japan

The raccoon dog (Nyctereutes procyonoides viverrinus) has recently become common in urban environments in Japan. We predicted that, like other carnivores adapted to urban environments, raccoon dogs in urban areas should have smaller home ranges than those in rural areas. We investigated the size of home ranges of raccoon dogs in the Akasaka Imperial Grounds, a 51-ha green area in central Tokyo. Between August 2012 and August 2014, 7 adult males and 4 adult females were radiotracked. Mean (± SD) home range size of these 11 raccoon dogs (100% minimum convex polygon = 17.6 ± 13.0 ha; 95% fixed kernel = 8.3 ± 5.7 ha) was smaller than that of raccoon dogs in rural areas obtained in previous studies, and core areas (75% local convex hull) averaged 3.7 ± 4.1 (SD) ha. We detected no seasonal changes in home range size. These results were consistent with the notion that urban carnivores typically have small home ranges. The small home range size seems to be explained by abundance of food resources, restricted environment, and the high population density of raccoon dogs in the urban green area.

Assessing shortfalls and complementary conservation areas for national plant biodiversity in South Korea.

Protected areas (PAs) are often considered the most important biodiversity conservation areas in national plans, but PAs often do not represent national-scale biodiversity. We evaluate the current conservation status of plant biodiversity within current existing PAs, and identify potential additional PAs for South Korea. We modeled species ranges for 2,297 plant species using Multivariate Adaptive Regression Splines and compared the level of mean range representation in South Korea’s existing PAs, which comprise 5.7% of the country’s mainland area, with an equal-area alternative PA strategy selected with the reserve algorithm Marxan. We also used Marxan to model two additional conservation scenarios that add lands to approach the Aichi Biodiversity Target objectives (17% of the country). Existing PAs in South Korea contain an average of 6.3% of each plant species’ range, compared to 5.9% in the modeled equal-area alternative. However, existing PAs primarily represent a high percentage of the ranges for high-elevation and small range size species. The additional PAs scenario that adds lands to the existing PAs covers 14,587.55 km2, and would improve overall plant range representation to a mean of 16.8% of every species’ range. The other additional PAs scenario, which selects new PAs from all lands and covers 13,197.35 km2, would improve overall plant range representation to a mean of 13.5%. Even though the additional PAs that includes existing PAs represents higher percentages of species’ ranges, it is missing many biodiversity hotspots in non-mountainous areas and the additional PAs without locking in the existing PAs represent almost all species’ ranges evenly, including low-elevation ones with larger ranges. Some priority conservation areas we identified are expansions of, or near, existing PAs, especially in northeastern and southern South Korea. However, lowland coastal areas and areas surrounding the capital city, Seoul, are also critical for biodiversity conservation in South Korea.

Insight into the support effect on the particle size effect of Pt/C catalysts in dehydrogenation

The support effect and metal particle size effect, which are often intertwined, are two critical factors influencing the activity of a supported metal catalyst. To clarify each effect on the activity of carbon-supported Pt catalysts, a series of Pt/C catalysts were elaborately prepared by adopting two carbon materials with distinct microstructures—that is, carbon nanofibers (CNFs) vs carbon nanotubes (CNTs)—and by altering the Pt particle size from 1 to 9 nm on each support. The catalytic activity was assessed during the dehydrogenation of decalin to release hydrogen. Molecular dynamics simulations based on reactive force field and density functional theoretical calculations were employed in combination with catalyst characterization techniques. Significant differences in both the geometric structure and electronic properties of Pt clusters between two kinds of Pt/C catalysts have been found, especially in the Pt particle size range smaller than 2 nm. The edge planes of CNFs can interact much more strongly with Pt atoms than the basal planes of CNTs do, hence forming a more dispersive and simultaneously more active Pt-C boundary for reaction proceeding. The carbon support effect dominates the activity divergence in the smaller size range (<2 nm), while the Pt particle size effect prevails on the catalysts with medium Pt particles (2–4 nm). Both effects can fade out with continually increasing Pt particle size.

Traits indicating a conservative resource strategy are weakly related to narrow range size in a group of neotropical trees

Biological traits may co-determine differences in geographical range sizes among closely related species. In plants, trait values linked to a conservative resource-use strategy have been hypothesised to be associated with small range sizes. However, the empirical support is mixed and limited to extra-tropical species so far. Here, we analyse the relationship between range size and eight functional traits linked to the plant economics spectrum in congeneric pairs of neotropical tree species of Costa Rica with contrasting range sizes. In the lowland tropical rainforests of southern Costa Rica, we sampled 345 trees from 35 species in 14 genera and measured leaf thickness, leaf dry matter content, specific leaf area, wood specific gravity (WSG), leaf nitrogen (N), leaf phosphorus, leaf potassium and leaf N:P ratio. For each species, we estimated range size as the extent of occurrence using known localities of occurrence. We correlated range sizes with trait data scaled within-genus and with the principal components of the multivariate trait space. WSG was higher and leaf N was lower in species with small range sizes in univariate regression models, although these traits were only weakly related to range size. None of the other six traits was correlated with range size. Results were similar for a model using the principal components of the multivariate trait space, which explained 36% of the variation in species’ extent of occurrence. Again, the traits most strongly associated with the selected components were WSG and leaf N. Although high WSG and low leaf N can be interpreted as indicators of conservative resource-use, we could not detect strong relationships between the respective trait syndrome and range size in our sample of species. Traits related to conservative resource use may hence be involved in determining the range size of the species analysed, but other factors are apparently more important.

Inferring climatic controls of rice stem borers’ spatial distributions using maximum entropy modelling

AbstractAccurate assessment of pest potential distributions is needed to identify their establishment risks that play a key role in pest management in agricultural ecosystems. We used a correlative niche modelling method (Maxent) to predict and map the spatial distributions of two important rice stem borers, Chilo suppressalis and Sesamia cretica, in paddy fields of Iran. In total, 195 presence occurrence records (101 records for C. suppressalis and 94 records for S. cretica) were compiled. A set of environmental and topographic variables, with the highest effects on the species distributions and the lowest correlations among themselves, were used. The results showed that mainly the northern parts of Iran were the most suitable areas for C. suppressalis, and north, north‐east and south‐west of Iran as the most suitable areas for S. cretica. Both models performed well, with an area under the receiver operating characteristic curve (AUC) of 0.983 and 0.786 for C. suppressalis and S. cretica, respectively. The Maxent models showed higher accuracy for predicting the distribution of the specialist pest with the small range sizes compared to the generalist species. Assessing the importance of environmental variables, which were derived from the jackknife test, showed the precipitation as the variable with the highest contribution (66%) in explaining the spatial distribution of C. suppressalis compared to the other variables. The distribution of S. cretica was influenced by a set of variables derived from both the precipitation and temperature. The Maxent predictions were useful to map the geographical distributions of the risk for both rice stem borers that is needed to develop effective management strategies.

Sunlight mediated rapid synthesis of small size range silver nanoparticles using Zingiber officinale rhizome extract and its antibacterial activity analysis

ABSTRACTHerein we report the green synthesis of silver nanoparticles (AgNPs) completed within a rapid time of 2 hrs using Zingiber officinale rhizome extract in presence of sunlight. Characterization of nanoparticles was carried out by UV-Vis spectroscopy, HR-TEM, XRD and FTIR. Under TEM analysis, the size of the biosynthesized AgNPs was found to be remarkably small with size range of 4 to 15 nm. The AgNPs also exhibited excellent antibacterial activity against Staphylococcus aureus and Escherichia coli. MIC and MBC was found to be 62.5 µg/mL and 500 µg/mL for S. aureus, 125 µg/mL and 250 µg/mL for E. coli respectively.

Evaluation of a Pulse Width Modulated Bypass Nozzle for the Development of a Variable Load Residential Oil Burner

Due to the need for energy conservation in buildings and the simultaneous benefit of cost savings, the development of a low firing rate load modulating residential oil burner is very desirable. One of the two main requirements of such a burner is the development of a burner nozzle that is able to maintain the particle size distribution of the fuel spray in the desirable (small) size range for efficient and stable combustion. The other being the ability to vary the air flow rate and air distribution around the fuel nozzle in the burner for optimal combustion at the current fuel firing rate. In this paper, which deals with the first requirement, we show that by using pulse width modulation in the bypass channel of a commercial off-the-shelf bypass nozzle, this objective can be met. Here we present results of spray patterns and particle size distribution for a range of fuel firing rates. The results show that a desirable fuel spray pattern can be maintained over a fuel firing rate turndown ratio (Maximum Fuel Flow Rate/Minimum Fuel Flow Rate) of 3.7. Thus here we successfully demonstrate the ability to electronically vary the fuel firing rate by more than a factor of 3 while simultaneously maintaining good atomization.

Site fidelity, diel and seasonal activities of yellow‐phase Japanese eels (Anguilla japonica) in a freshwater habitat as inferred from acoustic telemetry

AbstractJapanese eels (Anguilla japonica) perform large‐scale oceanic migrations between their spawning ground and growth habitats in continental waters during life history. However, between these migrations, they spend most of time in growth habitats such as rivers. To investigate the diel and seasonal activities, homing behaviour and home range of yellow‐phase Japanese eels in the lower reach of the Tone River, we tracked them throughout a year using a fine‐scale positioning system (VPS) based on acoustic telemetry. The tracked eels were generally nocturnal, but not exclusively. They were mainly mobile from spring to autumn, with little or no activity observed during winter. A transport‐release experiment showed that most eels returned to their original capture area within 13 days after release. The eels had very small home ranges (mean ± SD = 0.085 ± 0.068 km2), core areas (0.014 ± 0.014 km2) and linear home ranges (744 ± 268 m). They also tended to be distributed on one particular side of the river (right or left bank) and in one particular shore type (revetment or vegetation), rarely moving from one to the other. This study provides evidence for nocturnal, dormancy, homing behaviours, limited habitat use and small home range size in Japanese eels. The eels clearly showed strong fidelity to a “familiar” site, which contrasts with the long distances travelled during upstream and downstream migration phases in the river, and during spawning migrations in the ocean.

Anthropogenic landscapes support fewer rare bee species

The response of rare species to human land use is poorly known because rarity is difficult to study; however, it is also important because rare species compose most of biodiversity, and are disproportionately vulnerable. Regional bee pollinator faunas have not been assessed for rarity outside of Europe. Therefore, we do not know to what extent anthropogenic landscapes support rare North American bee biodiversity. We ask how richness and abundance of bee species respond to land use, within quartiles of species defined by their numerical, phenological, and geographical rarity. We conducted a field study to sample bee communities in forested, agricultural, and urban landscapes replicated across a large spatial extent of the northeastern United States. We used large independent data sets to classify observed bee species according to three forms of rarity: their numerical rarity (low regional frequency in a museum-based data set), phenological rarity (short flight season length) and geographical rarity (small range size). For all three forms of rarity, we found half as many rare bee species in agricultural landscapes compared to forest. We found half as many phenologically rare species in urban landscapes. Bees that had both shorter flight seasons and smaller range sizes were between one-third and one-half as rich in both types of anthropogenic landscapes, regardless of regional frequency. Although a minority of rare bee species were found in anthropogenic landscapes, our overall conclusion is that the native vegetation of our region, forest, is critical for supporting rare bee biodiversity.