Black Periodic and Black Bauer Methods for Tissue Polysaccharides

m-Aminophenol gives a more rapid and more complete blockage of the Schiff reaction of aldehydes produced in tissue by oxidation with periodic or chromic acid than does aniline. Moreover, the phenol thus attached to aldehyde sites in tissue can then be azo coupled with alkaline solutions of fresh or stabilized diazonium salts. When so used at pH 8, fast black K, C.I. 37190, shows glycogen, mucins, basement membranes, muscle stroma, fungus cell walls, etc. stained black, on a somewhat grayish pink to red background.     

Black algae

Many species of cyanophytes, especially those growing on tiles and walls exposed to air and sunlight, appear black due to the presence of pigments in the mucilaginous cell-walls. Such pigments may serve a protective role against adverse effects of ultraviolet light but, overlying the ordinary intracellular blue-green pigments, they make the algal clumps look black. Among the most familiar of such algae are species of Gloeocapsa, which by discolouring pale surfaces of public or private premises can constitute a nuisance responsible for a considerable loss of financial value.     

Occupancy Patterns of Breeding American Black Ducks

Occupancy patterns can assist with the determination of habitat limitation during breeding or wintering periods and can help guide population and habitat management efforts. American black ducks (Anas rubripes; black ducks) are thought to be limited by habitat and food availability during the winter, but breeding sites may also limit the size or growth potential of the population. The Canadian Wildlife Service conducts an annual breeding waterfowl survey that we used to explore the hypothesis that black duck carrying capacity is limited by wetlands available for breeding in Québec, Canada. We applied single-visit, multi-species occupancy models to the 1990–2015 population survey data to determine if there was evidence the black duck population was limited by breeding habitat. Using a dynamic (multi-season) occupancy modeling approach, we estimated latent occupancy (occupancy accounting for imperfect detection) of black ducks and then used latent occupancy estimates to derive occupancy, colonization, and extirpation rates. We jointly modeled the occupancy dynamics of black ducks and other duck species in wetlands where both species were present. Throughout the duration of the survey, 44% of wetlands were never observed to be occupied by black ducks. Occupancy models showed wetland size was positively associated with occupancy at the first time step (initial occupancy) and colonization. All 2-species models indicated initial black duck occupancy, persistence (continued occupancy), and colonization were positively associated with the presence of a second species. Colonization rate over the 26-year period ranged from 7% to 27% across all models. Extirpation rates were similar and were constant through time within each model. Low occupancy rates, combined with approximately equal colonization and extirpation rates, suggest there are available wetlands for breeding black ducks in their core breeding area. If breeding habitats are not saturated, this suggests migration or wintering areas may be more limiting to black duck population abundance. © 2019 The Wildlife Society.     

Contrasting Activity Patterns of Sympatric and Allopatric Black and Grizzly Bears

ABSTRACT The distribution of grizzly (Ursus arctos) and American black bears (U. americanus) overlaps in western North America. Few studies have detailed activity patterns where the species are sympatric and no studies contrasted patterns where populations are both sympatric and allopatric. We contrasted activity patterns for sympatric black and grizzly bears and for black bears allopatric to grizzly bears, how human influences altered patterns, and rates of grizzly-black bear predation. Activity patterns differed between black bear populations, with those sympatric to grizzly bears more day-active. Activity patterns of black bears allopatric with grizzly bears were similar to those of female grizzly bears; both were crepuscular and day-active. Male grizzly bears were crepuscular and night-active. Both species were more night-active and less day-active when ≤1 km from roads or developments. In our sympatric study area, 2 of 4 black bear mortalities were due to grizzly bear predation. Our results suggested patterns of activity that allowed for intra- and inter-species avoidance. National park management often results in convergence of locally high human densities in quality bear habitat. Our data provide additional understanding into how bears alter their activity patterns in response to other bears and humans and should help park managers minimize undesirable bear-human encounters when considering needs for temporal and spatial management of humans and human developments in bear habitats.     

A Century of Hybridization: Decreasing Genetic Distance Between American Black Ducks and Mallards

American black ducks (Anas rubripes) and mallards (A. platyrhynchos) are morphologically and behaviorally similar species that were primarily allopatric prior to European colonization of North America. Subsequent sympatry has resulted in hybridization, and recent molecular analyses of mallards and black ducks failed to identify two distinct taxa, either due to horizontal gene flow, homoplasy, or shared ancestry. We analyzed microsatellite markers in modern and museum specimens to determine if the inter-relatedness of mallards and black ducks was an ancestral or recent character. Gst, a measure of genetic differentiation, decreased from 0.146 for mallards and black ducks living before 1940, to 0.008 for birds taken in 1998. This is a significant reduction in genetic differentiation, and represents a breakdown in species integrity most likely due to hybridization. Using modern specimens, we observed that despite a lower incidence of sympatry, northern black ducks are now no more distinct from mallards than their southern conspecifics.     

Evidence for Black Duck Winter Distribution Change

ABSTRACT The Mississippi Flyway midwinter population survey (MWS) indicates that American black ducks (Anas rubripes) have been rapidly declining for the last 10 years. We found a negative relationship between MWS and Ontario (Canada) midwinter counts for black ducks. Thus, as number of black ducks in the MWS decreased, Ontario midwinter counts increased. A shift in midwinter distribution of black ducks may be partly responsible for the decreasing trend in MWS counts. We recommend that midwinter black duck surveys be expanded to more sites in southern Canada and northeastern United States that currently are not sampled to better assess winter habitat use and improve the midwinter black-duck population index.     

Black fly larvae facilitate community recovery in a mountain stream

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Tanner Staging of Secondary Sexual Characteristics and Body Composition,Blood Pressure,and Insulin in Black Girls

Objective: To assess Tanner staging (breast and pubic hair development) and its relationship to measures of body composition, blood pressure, and fasting insulin and glucose in young black girls. Research Methods and Procedures: Subjects were 138 black girls, 8 to 12 years of age, recruited from elementary schools in low socioeconomic status neighborhoods. Exclusion criteria included the presence of any acute/chronic medical conditions. Pubertal stages were assessed by one of two pediatricians and analyzed individually, as well as with a composite index (prepubertal, pubertal/premenarcheal, or pubertal/menarcheal). Glucose and insulin were measured after a 12‐hour fast. Measures of body composition included height, weight, BMI, waist and hip circumferences, fat mass, fat‐free soft tissue, bone mineral density (DXA), and visceral adipose tissue (magnetic resonance imaging). Resting systolic and diastolic blood pressure were measured by Dinamap. Results: With age in the model, breast development explained significant proportions of the variance in height, weight, fat‐free soft tissue, bone mineral density, and insulin. Adding pubic hair development or menarche to those models did not significantly increase the proportion of variance that was explained by breast development. Furthermore, using a composite index of pubertal staging explained a smaller proportion of the variance compared with breast development alone. Discussion: Combined with age, breast development was a better predictor of body composition and fasting insulin than was pubic hair development or a composite index of pubertal staging.     

A Multiscale Assessment of Den Selection by Black Bears in Louisiana

ABSTRACT Understanding den selection for the federally threatened Louisiana black bear (Ursus americanus luteolus) will assist managers in effectively managing bear populations and the landscapes they inhabit. We assessed den selection of 72 female Louisiana black bears at multiple spatial scales in northern and central Louisiana, USA. We used 230 den-years to examine den type preference, microhabitat characteristics of dens, and effects of landscape characteristics on den selection. We also evaluated reuse of tree dens and their availability across several study areas. Bears selected tree dens more frequently (65%) than ground dens. Most (55%) ground dens were associated with standing or downed trees, and most tree dens were in baldcypress (Taxodium distichum; 86%) or surrounded by water (80%). Selection of ground dens was positively associated with landscape metrics related to presence of water, whereas selection of tree dens was positively associated with proximity to edge and greater proportions of swamp and areas containing water. Reuse of tree dens averaged 15% (range = 0–20%) across study areas and our estimates of tree-den availability indicated that tree dens were not a limiting resource for Louisiana black bears in the northern or central portions of Louisiana. Although Louisiana black bears demonstrated plasticity in den selection, we recommend managers use forest management practices that conserve appropriate tree dens and create ground-denning opportunities, because both would promote the recovery of Louisiana black bear populations.     

Ethnic Differences in Correlates of Obesity between Latin‐American and Black Women

Objective: To date, no studies have examined dietary intake, physical activity, and body image in a large sample of Latin‐American and black women recruited using the same methodology. The aim of this study was to examine three potential correlates of obesity (dietary intake, body image, and physical activity) in a large sample of Latin‐American and black women across the weight spectrum. Research Methods and Procedures: Participants were black (n = 271) and Latin‐American (n = 234) adult women who completed a 24‐hour dietary recall and physical activity and body image questionnaires. Results: After controlling for BMI, education, marital status, and number of children, black women consumed more kilocalories, dietary fat (grams), and percent calories from fat than Latin‐American women, who consumed more carbohydrates (grams) and dietary fiber (total and soluble). Black women engaged in more sedentary behavior than Latin‐American women. Although Latin‐American women weighed less than black women, they perceived their current body image as heavier and reported greater body image dissatisfaction than black women. Black women also reported a higher ideal body image than Latin‐American women. Discussion: The combined effect of a diet higher in calories and fat, increased sedentary behavior, and more accepting body image could account for higher rates of obesity among black women. Future studies should further explore cultural attitudes and beliefs related to weight that could provide information for the development of culturally competent obesity interventions.     

Volatile Flavor of Black Tea

The first effluent of essential oil of black tea in the gas chromatographic analysis is important for characterizing black tea flavor. The isolation and identification of main unknown components were conducted by means of gas chromatography, and also by infrared spectra and ultraviolet spectra. Ethylacetate, ethylalcohol and β-myrcene were identified as the increasing compounds during fermentation. cis-β-Ocimene and trans-β-ocimene were also identified only in completely manufactured black tea. These three terpenoid hydrocarbons are newly found constituents of essential oil of black tea and are supposed to contribute considerably to the black tea flavor.     

Association Between the 4 bp Proinsulin Gene Insertion Polymorphism (IVS‐69) and Body Composition in Black South African Women

The objective of the study was to examine the association between a functional 4 bp proinsulin gene insertion polymorphism (IVS‐69), fasting insulin concentrations, and body composition in black South African women. Body composition, body fat distribution, fasting glucose and insulin concentrations, and IVS‐69 genotype were measured in 115 normal‐weight (BMI <25 kg/m²) and 138 obese (BMI ≥30 kg/m²) premenopausal women. The frequency of the insertion allele was significantly higher in the class 2 obese (BMI ≥35kg/m²) compared with the normal‐weight group (P = 0.029). Obese subjects with the insertion allele had greater fat mass (42.3 ± 0.9 vs. 38.9 ± 0.9 kg, P = 0.034) and fat‐free soft tissue mass (47.4 ± 0.6 vs. 45.1 ± 0.6 kg, P = 0.014), and more abdominal subcutaneous adipose tissue (SAT, 595 ± 17 vs. 531 ± 17 cm², P = 0.025) but not visceral fat (P = 0.739), than obese homozygotes for the wild‐type allele. Only SAT was greater in normal‐weight subjects with the insertion allele (P = 0.048). There were no differences in fasting insulin or glucose levels between subjects with the insertion allele or homozygotes for the wild‐type allele in the normal‐weight or obese groups. In conclusion, the 4 bp proinsulin gene insertion allele is associated with extreme obesity, reflected by greater fat‐free soft tissue mass and fat mass, particularly SAT, in obese black South African women.     

Relation of Misperception of Healthy Weight to Obesity in Urban Black Men

This study examined the relation between misperception of healthy weight and obesity, as well as moderators of this relation, in a sample of middle‐aged black men. Survey data from 404 mostly immigrant, black males living in greater New York City were collected as part of a larger randomized controlled trial. Data included measures of health status, BMI, perceived healthy weight, and misperception of healthy weight. Misperception of healthy weight was more frequent among obese men (90.2%) than nonobese men (48.7%) (P < 0.001). Mean level of misperception was also significantly higher in obese men than nonobese men (P < 0.001). Health status moderated the relation between misperception of healthy weight and obesity: obese men who felt healthy or who had fewer comorbid conditions had greater misperception of healthy weight than obese men who felt unhealthy or had relatively more comorbid conditions (P < 0.01). Our findings demonstrate that misperception of healthy weight discriminates between obese and nonobese black men, and the magnitude of this relation is exacerbated in obese men who are relatively healthy. Future studies should determine the prevalence of misperception of healthy weight in more diverse populations and identify potential mediators of the relation between misperception of healthy weight and obesity.     

Black bear movements and habitat use during a critical period for moose calves

In sub-Arctic and north-temperate ecosystems, opportunistic carnivores, such as black bears (Ursus americanus) and brown bears (Ursus arctos), are active on the landscape for a shorter period annually than sympatric gray wolves (Canis lupus). Therefore, bear movement patterns and habitat use might be expected to be more deliberate and of greater consequence, in terms of energy acquisition, than those of predators not undergoing hibernation. Habitat choices concerning feeding, bedding, and denning grounds made by black bears therefore should reflect seasonal abundance and distribution of vegetation and key prey items as these are sites where bears remain and forage for prolonged periods of time. We recorded the movement patterns of 6 GPS-collared black bears from den emergence to onset of moose (Alces alces) parturition in 2003. Over approximately 3 weeks prior to parturition, results from average distance calculations suggest that black bears moved closer to probable moose calving-site habitat. Additionally, the seasonal habitat use by black bears surrounding dens reflected the same trend for areas where cow moose gave birth in spring 2003, with a propensity to use needleleaf forest more than any other habitat.     

Black soybean extract can attenuate thrombosis through inhibition of collagen-induced platelet activation

Many clinical trials have demonstrated the beneficial effects of soybean (Glycine max) on general cardiovascular health. Among a variety of soybeans, black soybean is known to display diverse biological activities superior to those of yellow and green soybeans, such as in antioxidant, anti-inflammatory and anticancer activities. However, few studies have been directed on the effect of black soybean on cardiovascular function. In this study, we aimed to investigate the effect of black soybean extract (BB) on platelet activation, a key contributor to thrombotic diseases. In freshly isolated human platelets, BB has shown potent inhibitory activity on collagen-induced platelet aggregation, while yellow soybean extract had marginal activity only. BB also attenuated serotonin secretion and P-selectin expression, which are important factors for the platelet–tissue interaction along with thromboxane A₂ formation. These in vitro results were further confirmed in an ex vivo platelet aggregation measurement and in vivo venous thrombosis model where oral administration of BB reduced collagen-induced platelet aggregation and FeCl₃-induced thrombus formation significantly. A potential active ingredient for antiplatelet effects of BB was isolated and identified to be adenosine through bioassay-directed fractionation and NMR and ESI-MS analyses. These results indicate that black soybean can be a novel dietary supplement for the prevention of cardiovascular risks and the improvement of blood circulation.     

A Sudan Black B Myelin Stain for Peripheral Nerves

Blocks of fresh issue were fixed 2 or more days in: cobalt sulfate (or nitrate), 1 gm; distilled water, 80 ml; 10% calcium chloride, 10 ml; and formalin, 10 ml. The fixed tissue was washed thoroughly in tap water, embedded in gelatin, frozen sections cut, and mounted on slides with gelatin adhesive. The sections were stained 15-30 min in a saturated, filtered solution of Sudan black B in 70% alcohol, differentiated in 50% alcohol under microscopic observation, and a cover glass applied with glycerol-gelatin. In thick (50-100 μ) sections, myelin stained green to gray-green and this allowed easy differentiation between nerves and other tissue elements.     

Free and Bound Gibberellin Activities and Ent-kaurene Synthesis during Induction of Cold Hardiness in Black Locust Seedlings

The role of gibberellin in the development of cold hardiness in black locust (Robinia pseudoacacia L.) seedlings was investigated. Free and bound gibberellin activities were followed during induction of cold hardiness using ethyl acetate partitioning and pH variation, with subsequent paper chromatographic fractionation and gibberellin bioassay. While total gibberellin activity decreased during the induction of cold hardiness in black locust seedlings, no convincing evidence was found to support conversion of free gibberellin to a bound form. However, bound gibberellin activity did appear to be more stable than did free gibberellin activity during the final stages of cold hardening at freezing temperatures. Gibberellin synthesis was followed using ¹⁴C-mevalonate conversion to ent-kaurene in a cell-free extract of the tissue. Ent-kaurene synthesis decreased during cold hardening with no detectable synthesis in fully hardened seedlings. However, since growth cessation precedes development of cold hardiness, decreased gibberellin synthesis and corresponding trends in free and bound fractions might have been expected, and a cause and effect relationship is difficult to establish. Even so, a decline in one step in gibberellin synthesis and a greater stability of bound than free gibberelin activity are associated with induction of cold hardiness in black locust seedlings.     

Differential Effects of Abdominal Adipose Tissue Distribution on Insulin Sensitivity in Black and White South African Women

Black South African women are more insulin resistant than BMI‐matched white women. The objective of the study was to characterize the determinants of insulin sensitivity in black and white South African women matched for BMI. A total of 57 normal‐weight (BMI 18–25 kg/m²) and obese (BMI > 30 kg/m²) black and white premenopausal South African women underwent the following measurements: body composition (dual‐energy X‐ray absorptiometry), body fat distribution (computerized tomography (CT)), insulin sensitivity (S_I, frequently sampled intravenous glucose tolerance test), dietary intake (food frequency questionnaire), physical activity (Global Physical Activity Questionnaire), and socioeconomic status (SES, demographic questionnaire). Black women were less insulin sensitive (4.4 ± 0.8 vs. 9.5 ± 0.8 and 3.0 ± 0.8 vs. 6.0 ± 0.8 × 10^?5/min/(pmol/l), for normal‐weight and obese women, respectively, P < 0.001), but had less visceral adipose tissue (VAT) (P = 0.051), more abdominal superficial subcutaneous adipose tissue (SAT) (P = 0.003), lower SES (P < 0.001), and higher dietary fat intake (P = 0.001) than white women matched for BMI. S_I correlated with deep and superficial SAT in both black (R = ?0.594, P = 0.002 and R = 0.495, P = 0.012) and white women (R = ?0.554, P = 0.005 and R = ?0.546, P = 0.004), but with VAT in white women only (R = ?0.534, P = 0.005). In conclusion, body fat distribution is differentially associated with insulin sensitivity in black and white women. Therefore, the different abdominal fat depots may have varying metabolic consequences in women of different ethnic origins.     

Chemical Analysis of Melanin Pigments in Feather Germs of Japanese Quail Bh (Black at Hatch) Mutants

Bh (black at hatch) is a mutation of Japanese quails which causes darkening or lightening of the plumage in heterozygotes or homozygotes, respectively. We chemically analyzed melanin pigments in feather germs of Bh mutant embryos and in feathers of adult animals. Dark brown dorsal feathers of wild-type adult animals had white barrings, but heterozygous ones lacked clear barrings. The feathers of wild-type and heterozygote animals contained both eumelanins and pheomelanins, the latter being more pheomelanic. On the dorsal skin of 10-day old wild-type embryos, longitudinal stripes from black and yellow rows of feather germs developed; two or three longitudinal rows of black feather germs and then two or three rows of yellow feather germs next to the short central feather germs. Heterozygous embryos appeared black in plumage pigmentation, due to the presence of‘gray’feather germs in rows of dorsal feather germs that corresponded to yellow rows in wild-type embryos. Homozygous dorsal feather germs did not develop the black and yellow longitudinal stripes, but were brown. Chemical analysis showed that embryos of each genotype contained both eumelanins and pheomelanins in the feather germs; however, the eumelanin content in ho-mozygous feather germs was very low. These results suggest that the Bh mutation causes pheomelanic changes in feathers of quails.     

Determinants of insulin-resistant phenotypes in normal-weight and obese Black African women

Objective: Subsets of metabolically “healthy obese” and “at‐risk” normal‐weight individuals have been previously identified. The aim of this study was to explore the determinants of these phenotypes in black South African (SA) women. Methods and Procedures: From a total of 103 normal‐weight (BMI ≤ 25 kg/m²) and 122 obese (BMI ≥ 30 kg/m²) black SA women, body composition, fat distribution, blood pressure, fasting glucose levels, insulin resistance, and lipid profiles were measured. Questionnaires relating to family history, physical activity energy expenditure (PAEE), and socio‐demographic variables were administered. The subjects were classified as insulin sensitive or insulin resistant according to the homeostasis model assessment of insulin resistance (HOMA‐IR) (≥1.95 insulin resistant). Results: Our study showed that 22% of the normal‐weight women were insulin resistant and 38% of the obese women were insulin sensitive. Increased visceral adipose tissue (VAT) (P = 0.001) and decreased VAT/leg fat mass (P ≤ 0.001), independent of total body fatness, distinguished between the phenotypes. Moreover, the insulin‐sensitive women were of higher socioeconomic status, did more leisure and vigorous PAEE and were less likely to use injectable contraceptives. Using a regression model, body fat distribution, percent body fat, age, log leisure PAEE, and use of injected contraception accounted for 35% of the variance in HOMA‐IR in the normal‐weight women. In the obese women, 34% of the variance in HOMA‐IR was explained by the same variables, excluding PAEE. No differences in smoking status or family history of metabolic disease were found between the phenotypes. Discussion: Central fat distribution, total adiposity, socioeconomic status, leisure PAEE, and use of injectable contraceptives distinguished between insulin‐sensitive and insulin‐resistant black SA women.