Patterns of native and alien plant diversity in response to disturbance were examined along an elevational gradient in blue oak savanna, chaparral, and coniferous forests. Total species richness, alien species richness, and alien cover declined with elevation, at scales from 1 to 1000 m 2 . We found no support for the hypothesis that community diversity inhibits alien invasion. At the 1-m 2 point scale, where we would expect competitive interactions between the largely herbaceous flora to be most intense, alien species richness as well as alien cover increased with increasing native species richness in all communities. This suggests that aliens are limited not by the number of native competitors, but by resources that affect establishment of both natives and aliens.Blue oak savannas were heavily dominated by alien species and consistently had more alien than native species at the 1-m 2 scale. All of these aliens are annuals, and it is widely thought that they have displaced native bunchgrasses. If true, this means that aliens have greatly increased species richness. Alternatively, there is a rich regional flora of native annual forbs that could have dominated these grasslands prior to displacement by alien grasses. On our sites, livestock grazing increased the number of alien species and alien cover only slightly over that of sites free of livestock grazing for more than a century, indicating some level of permanency to this invasion.In chaparral, both diversity and aliens increased markedly several years after fire. Invasive species are rare in undisturbed shrublands, and alien propagules fail to survive the natural crown fires in these ecosystems. Thus, aliens necessarily must colonize after fire and, as a consequence, time since fire is an important determinant of invasive presence. Blue oak savannas are an important propagule source for alien species because they maintain permanent populations of all alien species encountered in postfire chaparral, and because the vegetation mosaic in this region places them in proximity to chaparral. The speed at which alien propagules reach a burned site and the speed at which the shrublands return to their former closed-canopy condition determine alien invasion. Frequent burning of this vegetation alters the balance in favor of alien invasion.In the higher-elevation coniferous forests, species diversity was a function of fire severity and time since fire. High-intensity fires create gaps that decrease canopy coverage and increase light levels and nutrients for an ephemeral successional flora. Few species have persistent seed banks, so the time since fire is an important determinant of colonization success. There was a highly significant interaction between fire severity and time since fire for understory cover, species richness, and alien richness and cover. Understory was sparse in the first year after fire, particularly in low-severity burns, and increased substantially several years after fire, particularly on high-severity burns. Both fire severity and time since fire ...

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Background: The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) provides a standardized reporting system for salivary gland fine-needle aspiration (SGFNA). We review the clinical utility of the MSRSGC at a tertiary care cancer center by assessing the rates of malignancy (ROM) among different categories.Methods: A retrospective search was performed to retrieve all SGFNA cases performed at our institution between 1/1/07 and 12/31/18. The initial primary diagnoses were recorded and cases were then assigned to appropriate MSRSGC categories. ROM was then calculated for all categories.Results: A total of 976 cases were identified, and 373 with follow-up. The ROM was 19.7% (192/976) for all-comers and 51.3% (192/374) among cases with follow-up.Using MSRSGC, SGFNA showed a sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 65.6%, 87.4%, 100%, and 72.6%, respectively. ROM for MSRSGC categories I, II, III, IVa, IVb, V, and VI were 20.7%, 30.0%, 45.8%, 3.3%, 50.7%, 100%, and 100%, respectively. Utilizing MSRSGC resulted in a nondiagnostic rate of 14.4%. The nondiagnostic rate was lower when the procedure was performed by pathologists vs nonpathologists (12.9% vs 15.8%) but was comparable when rapid on site evaluation (ROSE) was performed (12.9% vs 11.6%).Conclusion: In our patient population, MSRSGC resulted in a perfect PPV and moderate NPV. Utilizing MSRSGC results in a higher nondiagnostic rate due to the inclusion of cases with benign elements or cyst contents only in this category. Performing ROSE is more important in attaining an adequate sample than the specialty of the person performing SGFNA. K E Y W O R D Sfine-needle aspiration, Milan system for reporting salivary gland cytopathology, salivary gland

Objectives: To discover the risk factors for developing hypoglycemia in newborns born to diabetic mothers and to characterize the rates of glucose concentrations in the first two days of life. Methods: Retrospective recordings of medical charts of 576 healthy term infants of diabetic mothers during an 18-month period. We determined the following pre-feeding glucose concentrations: ‘normoglycemia’ (≥47 mg/dl = 2.6 mmol/l), ‘mild hypoglycemia’ (40–46 mg/dl = 2.2– 2.5 mmol/l), ‘moderate hypoglycemia’ (30–39 mg/dl = 1.7–2.1 mmol/l) and ‘severe hypoglycemia’ (<30 mg/dl = 1.7 mmol/l). Results: Glucose concentrations below ‘normoglycemia’ and ‘severe hypoglycemia’ were observed in 280 (48.6%) and 23 (4%) of the infants, respectively. The main risk factors for developing glucose concentrations below ‘normoglycemia’ in the first day of life were large size for gestational age and maternal insulin-dependent diabetes mellitus. ‘Severe hypoglycemia’ was more common among infants born to mothers who needed insulin (either type A2 or insulin-dependent diabetes mellitus). Infants born to mothers with insulin-dependent diabetes mellitus were less mature, heavier, large for their gestational age and exhibited more ‘severe and moderate hypoglycemia’ in the first day of life as compared to infants born to diabetes type A1 and A2 mothers. In addition, infants who were large for gestational age tended to have more ‘moderate hypoglycemia’ when born to diabetes type A1 mothers compared to small and appropriate-for-gestational-age infants. Thirty infants (5%) still had hypoglycemia on the second day of life. This subgroup of infants did not differ with regard to maternal-type diabetes. Conclusions: Infants born to diabetic mothers tend to have a high rate of hypoglycemia on the first day of life when a relatively high cut-off point (≥47 mg/dl = 2.6 mmol/l) is used. Infants born large for gestational age as well as those born to mothers with juvenile diabetes mellitus are at higher risk and should be closely monitored.