32 research outputs found
INVESTIGATING DISTRIBUTED LEADERSHIP PRACTICES OF ELEMENTARY PRINCIPALS IN A LARGE SCHOOL DISTRICT
Over the past few decades, the job of school leadership has become increasingly more demanding, creating a need to further understand how principals utilize leadership practices that support them on the job. The purpose of this study was to identify the extent to which principals report distributing leadership responsibilities and tasks in their schools, the ways in which they distribute these responsibilities and tasks, and the extent to which teacher leaders are afforded opportunities to assume leadership responsibilities and tasks in their schools. The study also explored the barriers and supporting factors that contribute to implementing distributed leadership practices at the school level.
This mixed-methods study utilized a web-based survey and semi-structured interviews to explore the following research questions: (1) To what extent do elementary principals report distributing leadership responsibilities and tasks to others in their schools? (2) What structures, processes, and tools do principals report using to distribute leadership in their schools? (3) To what extent do teacher leaders report assuming leadership responsibilities and tasks in their schools? (4) What do elementary principals perceive as the major barriers and supporting factors of implementing distributed leadership in their schools?
During the 20182019 school year, 111 elementary school principals and 115 teacher leaders or Instructional Lead Teachers (ILTs) participated in the study. The principals and teachers were at comprehensive model schools serving grades PreK5 and PreK6.
Findings from the study revealed principals distribute leadership to a variety of leaders in their buildings, specifically assistant principals and ILTs. Principals and teacher leaders both describe implementing organizational structures, processes, and tools to support distributed leadership in schools. Principals identified in both the survey and interview portion of the study reported that a lack of time to develop the capacity of teacher leaders, and to allow teacher leaders to practice leadership skills, was a major barrier to distributing leadership in schools. Data from principals showed that district level support was beneficial in helping principals engage in distributed leadership practices by providing professional development and other systemic initiatives that were implemented in their schools
Potable Water and Terrestrial Resources on Grand Bahama Post-Hurricane Dorian: Opportunities for Climate Resilience
The catastrophic impact of Hurricane Dorian in September 2019 was unprecedented for the island of Grand Bahama. Flooding in the western portion of the island damaged pine ecosystems, inundated the soil and groundwater with salt water, and disrupted potable water service throughout the island. More than two years post-Hurricane Dorian, the freshwater lenses that the island relies on for potable water are still inundated with salt water. This collaborative paper summarizes all efforts of researchers and practitioners to evaluate the freshwater lenses, as well as their associated ecosystems, that serve as the main source of drinking water for the island of Grand Bahama. Hydrogeologic and vegetation assessments were conducted on the two primary wellfields that provide 95% of the drinking water to the island, over the span of two and a half years from the immediate aftermath of Hurricane Dorian through present day. While salinity and total dissolved solid concentrations in groundwater have declined, present levels indicate that the full recovery of the freshwater lenses may take decades. Forest assessments indicate that in Wellfield 6, which was the primary source of potable water pre-Hurricane Dorian, the pine forests suffered significant damage with complete pine mortality and little regeneration of pine trees occurring, which could impact the underlying freshwater lens. Lessons learned from this event underscore the vulnerability of water resources in The Bahamas and the critical need for adaptation strategies to improve resilience to future extreme events and climate change
Potent and broad HIV-neutralizing antibodies in memory B cells and plasma.
CAPRISA, 2017.Abstract available in pdf
New genetic loci link adipose and insulin biology to body fat distribution.
Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms
Interleukin-21-Producing HIV-1-Specific CD8 T Cells Are Preferentially Seen in Elite Controllers ▿
A hallmark of human immunodeficiency virus type 1 (HIV-1) pathogenesis is the rapid loss of CD4 T cells leading to generalized immune dysfunction, including an exhausted CD8 T cell phenotype. Understanding the necessary factors that govern the functional quality and protective potential of antiviral T cell responses would facilitate rational vaccine design and improve therapeutic strategies to combat persistent infections. Mouse models of chronic viral infection demonstrate that interleukin-21 (IL-21), produced primarily by CD4 T cells, is required for the generation and maintenance of functionally competent CD8 T cells and viral containment. We reasoned that preserved IL-21 production during HIV-1 infection would be associated with enhanced CD8 T cell function, allowing improved viral control. Here we analyzed the ability of CD4 and CD8 T cells to produce several cytokines in addition to IL-21 ex vivo following stimulation with overlapping HIV-1 peptides. Both CD4 and CD8 T cells were able to produce IL-21 in response to HIV-1 infection, with the latter cell type more closely associated with viral control. Furthermore, IL-21-producing HIV-1-specific CD4 T cells (compared to those producing other cytokines) were the best indicator of functional CD8 T cells. Our results demonstrate that HIV-1-specific IL-21-producing CD8 T cells are induced following primary infection and enriched in elite controllers, suggesting a critical role for these cells in the maintenance of viremia control
Care of the dialysis patient: Primary provider involvement and resource utilization patterns - a cohort study
Abstract Background Efficient and safe delivery of care to dialysis patients is essential. Concerns have been raised regarding the ability of accountable care organizations to adequately serve this high-risk population. Little is known about primary care involvement in the care of dialysis patients. This study sought to describe the extent of primary care provider (PCP) involvement in the care of hemodialysis patients and the outcomes associated with that involvement. Methods In a retrospective cohort study, patients accessing a Midwestern dialysis network from 2001 to 2010 linked to United States Renal Database System and with >90 days follow up were identified (n = 2985). Outpatient visits were identified using Current Procedural Terminology (CPT)-4 codes, provider specialty, and grouped into quartiles-based on proportion of PCP visits per person-year (ppy). Top and bottom quartiles represented patients with high primary care (HPC) or low primary care (LPC), respectively. Patient characteristics and health care utilization were measured and compared across patient groups. Results Dialysis patients had an overall average of 4.5 PCP visits ppy, ranging from 0.6 in the LPC group to 6.9 in the HPC group. HPC patients were more likely female (43.4% vs. 35.3%), older (64.0 yrs. vs. 60.0 yrs), and with more comorbidities (Charlson 7.0 vs 6.0). HPC patients had higher utilization (hospitalizations 2.2 vs. 1.8 ppy; emergency department visits 1.6 vs 1.2 ppy) and worse survival (3.9 vs 4.3 yrs) and transplant rates (16.3 vs. 31.5). Conclusions PCPs are significantly involved in the care of hemodialysis patients. Patients with HPC are older, sicker, and utilize more resources than those managed primarily by nephrologists. After adjusting for confounders, there is no difference in outcomes between the groups. Further studies are needed to better understand whether there is causal impact of primary care involvement on patient survival
Tailoring Tfh profiles enhances antibody persistence to a clade C HIV-1 vaccine in rhesus macaques
CD4 T follicular helper cells (Tfh) are essential for establishing serological memory and have distinct helper attributes that impact both the quantity and quality of the antibody response. Insights into Tfh subsets that promote antibody persistence and functional capacity can critically inform vaccine design. Based on the Tfh profiles evoked by the live attenuated measles virus vaccine, renowned for its ability to establish durable humoral immunity, we investigated the potential of a Tfh1/17 recall response during the boost phase to enhance persistence of HIV-1 Envelope (Env) antibodies in rhesus macaques. Using a DNA-prime encoding gp160 antigen and Tfh polarizing cytokines (interferon protein-10 (IP-10) and interleukin-6 (IL-6)), followed by a gp140 protein boost formulated in a cationic liposome-based adjuvant (CAF01), we successfully generated germinal center (GC) Tfh1/17 cells. In contrast, a similar DNA-prime (including IP-10) followed by gp140 formulated with monophosphoryl lipid A (MPLA) +QS-21 adjuvant predominantly induced GC Tfh1 cells. While the generation of GC Tfh1/17 cells with CAF01 and GC Tfh1 cells with MPLA +QS-21 induced comparable peak Env antibodies, the latter group demonstrated significantly greater antibody concentrations at week 8 after final immunization which persisted up to 30 weeks (gp140 IgG ng/ml- MPLA; 5500; CAF01, 2155; p<0.05). Notably, interferon γ+Env-specific Tfh responses were consistently higher with gp140 in MPLA +QS-21 and positively correlated with Env antibody persistence. These findings suggest that vaccine platforms maximizing GC Tfh1 induction promote persistent Env antibodies, important for protective immunity against HIV