Pollination Characteristics of Blowout Penstemon (\u3ci\u3ePenstemon haydenii\u3c/i\u3e S. Watson)

The pollination characteristics of blowout penstemon (Penstemon haydenii S. Wats.), the only officially endangered plant species in Nebraska, were investigated. Cross-pollination was determined to be the major method of pollination, but self-pollination also occurs. Insects increased cross-pollination. The natural habitat of blowout penstemon has greatly decreased during this century, resulting in only a few isolated populations. The opportunity for cross-pollination with other populations no longer exists. Without crosspollination, lowered genetic diversity of the species may result in less vigorous plants and declining populations. Introduction of new genetic material into declining populations may help to assure the continued existence of the species

Blowouts in the Nebraska Sandhills: The Habitat of \u3ci\u3ePenstemon haydenii\u3c/i\u3e

The Nebraska Sandhills is the largest area of sand dunes in the Western Hemisphere, occupying over 5 million ha in northcentral Nebraska. The rolling to steep dunes range in height from a few meters to over 60 m. Soils are poorly developed in wind deposited sand. The continental climate is characterized by 425 to 625 mm of annual precipitation, an average annual temperature of 10 C, and a frost-free period of 130-155 days. Upland vegetation is primarily tall grasses and midgrasses such as sand bluestem [Andropogon gerardii var. paucipilus (Nash) Fern.], prairie sandreed [CaLamovilfa Longifolia (Hook.) Scribn.], little bluestem [Schizachyrium scoparium (Michx.) Nash], and switchgrass (Panicum virgatum L.). Forbs are common. Wind erosion occurs when the protective cover of vegetation is destroyed. Blowouts are active sites of erosion. Blowouts are irregular or conical craters formed when the deep, loose sands are removed by swirling action of the prevailing northwesterly winds. Blowout penstemon (Penstemon haydenii S. Wats.) is only found on these sites of active wind erosion and is an early successional species. Important associated species in blowouts include blowout grass [Redfieldia flexuosa (Thurb.) Vasey] and lemon scurfpea (Psoralea Lanceolata Pursh). The number of blowouts has decreased with the control of fire and improved range management techniques. Loss of suitable habitat is one of the reasons for the decline of blowout penstemon. At the same time, there are many blowouts in the Sandhills that seem to offer suitable habitat where blowout penstemon is not found

Blowouts in the Nebraska Sandhills: The Habitat of \u3ci\u3ePenstemon haydenii\u3c/i\u3e

The Nebraska Sandhills is the largest area of sand dunes in the Western Hemisphere, occupying over 5 million ha in northcentral Nebraska. The rolling to steep dunes range in height from a few meters to over 60 m. Soils are poorly developed in wind deposited sand. The continental climate is characterized by 425 to 625 mm of annual precipitation, an average annual temperature of 10 C, and a frost-free period of 130-155 days. Upland vegetation is primarily tall grasses and midgrasses such as sand bluestem [Andropogon gerardii var. paucipilus (Nash) Fern.], prairie sandreed [CaLamovilfa Longifolia (Hook.) Scribn.], little bluestem [Schizachyrium scoparium (Michx.) Nash], and switchgrass (Panicum virgatum L.). Forbs are common. Wind erosion occurs when the protective cover of vegetation is destroyed. Blowouts are active sites of erosion. Blowouts are irregular or conical craters formed when the deep, loose sands are removed by swirling action of the prevailing northwesterly winds. Blowout penstemon (Penstemon haydenii S. Wats.) is only found on these sites of active wind erosion and is an early successional species. Important associated species in blowouts include blowout grass [Redfieldia flexuosa (Thurb.) Vasey] and lemon scurfpea (Psoralea Lanceolata Pursh). The number of blowouts has decreased with the control of fire and improved range management techniques. Loss of suitable habitat is one of the reasons for the decline of blowout penstemon. At the same time, there are many blowouts in the Sandhills that seem to offer suitable habitat where blowout penstemon is not found

Blowouts in the Nebraska Sandhills: The Habitat of \u3ci\u3ePenstemon haydenii\u3c/i\u3e

The Nebraska Sandhills is the largest area of sand dunes in the Western Hemisphere, occupying over 5 million ha in northcentral Nebraska. The rolling to steep dunes range in height from a few meters to over 60 m. Soils are poorly developed in wind deposited sand. The continental climate is characterized by 425 to 625 mm of annual precipitation, an average annual temperature of 10 C, and a frost-free period of 130-155 days. Upland vegetation is primarily tall grasses and midgrasses such as sand bluestem [Andropogon gerardii var. paucipilus (Nash) Fern.], prairie sandreed [CaLamovilfa Longifolia (Hook.) Scribn.], little bluestem [Schizachyrium scoparium (Michx.) Nash], and switchgrass (Panicum virgatum L.). Forbs are common. Wind erosion occurs when the protective cover of vegetation is destroyed. Blowouts are active sites of erosion. Blowouts are irregular or conical craters formed when the deep, loose sands are removed by swirling action of the prevailing northwesterly winds. Blowout penstemon (Penstemon haydenii S. Wats.) is only found on these sites of active wind erosion and is an early successional species. Important associated species in blowouts include blowout grass [Redfieldia flexuosa (Thurb.) Vasey] and lemon scurfpea (Psoralea Lanceolata Pursh). The number of blowouts has decreased with the control of fire and improved range management techniques. Loss of suitable habitat is one of the reasons for the decline of blowout penstemon. At the same time, there are many blowouts in the Sandhills that seem to offer suitable habitat where blowout penstemon is not found

Propagation of Blowout Penstemon (\u3ci\u3ePenstemon haydenii\u3c/i\u3e S. Wats.)

Propagating and developing plants for successful transplanting will be important for the recovery of Nebraska\u27s only endangered plant species, blowout penstemon (Penstemon haydenii S. Wats.). Therefore, the effect of various cultural treatments on seedling growth was examined in a greenhouse study. Young blowout penstemon seedlings, fertilized with both nitrogen and phosphorus, exhibited significantly greater weekly growth rates than seedlings fertilized with one or no nutrient. After removal of the upper part of the shoot to the third pair of true leaves, only those seedlings fertilized with both nutrients exhibited a temporary increase in weekly growth rate and more axillary shoots

Propagation of Blowout Penstemon (\u3ci\u3ePenstemon haydenii\u3c/i\u3e S. Watson): Germination-enhancing Treatments

Development of germination-enhancing treatments will be essential for the recovery of Nebraska\u27s only officially endangered plant species, blowout penstemon (Pensiemon haydenii S, Watson), Effects of cold-moist stratification, mechanical or chemical scarification, and presence or absence of light in combination with alternating temperature regimes on seed germination of blowout penstemon was determined by laboratory studies. Stratified seeds exhibited greater mean germination percentages (21 %) than nonstratified seeds (8%). Effects of mechanical scarification on germination varied with trial. Seeds chemically scarified with concentrated sulfuric acid exhibited greater mean germination percentages (48%) than controls (12%); such scarification may substitute for the effective, but time-consuming, process of handscarification. Seeds were insensitive to light and alternating temperatures. Germination of freshly harvested seeds was not affected by storage of up to 15 weeks. Sulfuric acid and hand-scarification may be used to effectively enhance germination and, in tum, aid the recovery of this specie

Pollination Characteristics of Blowout Penstemon (\u3ci\u3ePenstemon haydenii\u3c/i\u3e S. Watson)

The pollination characteristics of blowout penstemon (Penstemon haydenii S. Wats.), the only officially endangered plant species in Nebraska, were investigated. Cross-pollination was determined to be the major method of pollination, but self-pollination also occurs. Insects increased cross-pollination. The natural habitat of blowout penstemon has greatly decreased during this century, resulting in only a few isolated populations. The opportunity for cross-pollination with other populations no longer exists. Without crosspollination, lowered genetic diversity of the species may result in less vigorous plants and declining populations. Introduction of new genetic material into declining populations may help to assure the continued existence of the species

Establishment and Survival of the Endangered Blowout Penstemon

Blowout penstemon (Penstemon haydenii S. Wats.) is the rarest plant endemic to the Great Plains and is the only officially endangered plant species in Nebraska. The endangered species recovery plan calls for an increase in viable populations from five to ten and an increase in plant numbers from about 6,000 to 15,000. Research conducted on survival of greenhouse grown seedlings transplanted at three sites in the Nebraska Sandhills showed that transplanting seedlings was feasible. Greatest survival was obtained when blowout penstemon seedlings were transplanted into blowout grass [Redfieldia flexuosa (Thurb.) Vasey] communities in blowout depressions. Plants were not long lived, but they produced seed for continuation of the species. Their relatively short life span may be directly related to the temporary aspect of suitable habitat in blowouts

Developmental Trajectories of Pediatric Obsessive–Compulsive Symptoms

Children who experience obsessive–compulsive symptoms (OCS) may be at risk for developing Obsessive–Compulsive Disorder (OCD). The current study aimed to investigate developmental trajectories of OCS, as well as possible predictors, within a community-based sample of children. Children (N = 1147) from the longitudinal NICHD Study of Early Child Care and Youth Development (SECCYD) were assessed for OCS, via the Child Behavioral Checklist – Obsessive–Compulsive Scale (OCS-8), eight times between Pre-Kindergarten (54 months; Pre-K) and High School (15 years of age; HS.) Participants were recruited within the United States and included only maternal caregivers. Preliminary analyses indicated that approximately 3% of the sample was above the diagnostic cutoff score on the OCS-8 at the High School time-point. Latent growth models tested symptom trajectories. Findings demonstrated three groups of OCS trajectories. Most children fell within a low symptomatology group (the No Peak group) with low OCS across all time points. Two additional OCS trajectories were also demonstrated: Pre-K Peak (high to low OCS across time) and HS Peak (low to high OCS across time). Both higher attention problems and greater depression/anxiety symptoms at the Pre-K time point predicted children’s membership in the Pre-K Peak or HS Peak groups compared to the No Peak group. Membership within the HS Peak group predicted a high likelihood of children’s OCS being above previously established cutoff scores for an OCD diagnosis at age 15 years. Membership within either the Pre-K Peak or No Peak groups predicted a low likelihood. This study provides new evidence for the existence of different developmental trajectories for youth with OCS. From a clinical perspective, these results may have important implications when considering the identification and early intervention of childhood OCS and OCD within the community

CureGN Study Rationale, Design, and Methods: Establishing a Large Prospective Observational Study of Glomerular Disease

Glomerular diseases, including minimal change disease, focal segmental glomerulosclerosis, membranous nephropathy, and immunoglobulin A (IgA) nephropathy, share clinical presentations, yet result from multiple biological mechanisms. Challenges to identifying underlying mechanisms, biomarkers, and new therapies include the rarity of each diagnosis and slow progression, often requiring decades to measure the effectiveness of interventions to prevent end-stage kidney disease (ESKD) or death. Multicenter prospective cohort study. Cure Glomerulonephropathy (CureGN) will enroll 2,400 children and adults with minimal change disease, focal segmental glomerulosclerosis, membranous nephropathy, or IgA nephropathy (including IgA vasculitis) and a first diagnostic kidney biopsy within 5 years. Patients with ESKD and those with secondary causes of glomerular disease are excluded. Clinical data, including medical history, medications, family history, and patient-reported outcomes, are obtained, along with a digital archive of kidney biopsy images and blood and urine specimens at study visits aligned with clinical care 1 to 4 times per year. Patients are followed up for changes in estimated glomerular filtration rate, disease activity, ESKD, and death and for nonrenal complications of disease and treatment, including infection, malignancy, cardiovascular, and thromboembolic events. The study design supports multiple longitudinal analyses leveraging the diverse data domains of CureGN and its ancillary program. At 2,400 patients and an average of 2 years’ initial follow-up, CureGN has 80% power to detect an HR of 1.4 to 1.9 for proteinuria remission and a mean difference of 2.1 to 3.0mL/min/1.73m2 in estimated glomerular filtration rate per year. Current follow-up can only detect large differences in ESKD and death outcomes. Study infrastructure will support a broad range of scientific approaches to identify mechanistically distinct subgroups, identify accurate biomarkers of disease activity and progression, delineate disease-specific treatment targets, and inform future therapeutic trials. CureGN is expected to be among the largest prospective studies of children and adults with glomerular disease, with a broad goal to lessen disease burden and improve outcomes