Preliminary results from the mineral ecosystem management area (EMA) experimental block study: One-year post-treatment. Special report to the Apache-Sitgreaves National Forests, USDA Forest Service, Region 3.

Southwestern ponderosa pine (Pinus ponderosa) forest ecosystems have become uncharacteristically dense as a result of livestock grazing, logging, and fire exclusion, which has led to an increase in vulnerability to high-severity, landscape-scale crown fires. In 2002, the Ecological Restoration Institute (ERI) at Northern Arizona University (NAU) and the Apache-Sitgreaves (A-S) National Forests cooperatively implemented a replicated ecological restoration experiment to (1) determine site-specific reference conditions, (2) measure and evaluate contemporary (pre-treatment) forest structure variables, and (3) test responses to three treatments: control, full restoration, and burn only. The site is located in a ponderosa pine forest and spans an elevation gradient from the pinyon-juniper ecotone to the dry mixed conifer ecotone. Reconstructed total basal area (BA) averaged 40 ft²/acre and total tree density averaged 35 trees/acre across all treatments indicating that a relatively open forest structure existed at the Mineral site in 1880. By 2002, prior to treatment, total BA had increased by more than 300% to an average of 125 ft²/acre and total tree density increased by more than 1000% to an average of 376 trees/acre. In 2009, following treatment, the full restoration treatment reduced total BA by 53% from 135 ft²/acre to 64 ft²/acre and total tree density by 83% from 404 trees/acre to 67 trees/acre. In the burn only treatment, total BA increased by 3% from 120 ft²/acre to 123 ft²/acre and tree density was reduced by 18% from 339 trees/acre to 279 trees/acre between 2002 and 2009. In the control, little change in total BA and tree density occurred between 2002 and 2009. Post-treatment diameter distributions in the full restoration treatment closely matched the historical distribution. In contrast, the burn only treatment had only small reductions in the lower diameter classes. Following treatment, about 15% of the presettlement trees died or were cut in the full restoration treatment compared to 23% mortality of presettlement trees in the burn only treatment. Ten percent of presettlement trees died in the control during the same time without active treatment. One year after application, the full restoration treatment shifted forest structure and diameter distributions within the range of variability historically present at the Mineral site. In contrast, the burn only treatment did not shift forest structure and diameter distributions within the historical range of variability in the short term. The ERI will conduct a five-year remeasurement at the Mineral site in the summer of 2013 and will build upon the information provided in this report to evaluate five-year post-treatment responses on forest structure, regeneration, surface fuels, canopy cover, herbaceous understory, and potential fire behavior

A demonstration project to test ecological restoration of a pinyon-juniper ecosystem

To test an approach for restoring historical stand densities and increasing plant species diversity of a pinyon-juniper ecosystem, we implemented a demonstration project at two sites (CR and GP) on the Grand Canyon-Parashant National Monument in northern Arizona. Historical records indicated that livestock grazing was intensive on the sites beginning in the late 1800s and continuing through the mid 1900s. Repeat aerial photographs (1940 and 1992) indicated recent increases in stand density and encroachment of trees into formerly open areas. Age distributions indicated that the majority of pinyon trees at both sites were less than 100 years of age and juniper establishment appeared to peak in the late 1800s to early 1900s, although some junipers had establishment dates as early as 1700-1725. Pretreatment understory communities were sparse (50% pinyon mortality, which was positively related to tree size and age. The demonstration treatment consisted of thinning small trees (< 25 cm diameter at root collar (DRC)), lopping and scattering thinned trees, and seeding native understory species. Thinning and mortality reduced overstory density from 638 and 832 trees per hectare pretreatment (258 and 337 trees per acre) to 280 and 251 trees per hectare (113 and 102 per acre) posttreatment at CR and GP, respectively. Posttreatment densities were similar to those suggested for the late 1800s by dendrochronological stand reconstructions. Thinning small diameter pinyon increased residual quadratic mean diameter (QMD) at CR and the relative importance of juniper at both sites. Live canopy fuels were reduced by treatment at CR and by thinning plus beetle-related mortality at GP. Although thinning slash was lopped and scattered, woody surface fuels were not significantly different between treated and control units at either site, perhaps due to the small size of thinned trees and the large interspace areas into which slash was scattered. Treatment had no immediate effects on herbaceous cover or species richness, both of which may take more time to develop. Further monitoring will help to clearly evaluate the effectiveness of this treatment for satisfying restoration and conservation goals

Native plants dominate understory vegetation following ponderosa pine forest restoration treatments

Dense ponderosa pine forests in the southwestern United States inhibit understory production and diversity and are susceptible to high-severity wildfire. Restoration treatments involving overstory thinning and prescribed burning are being implemented to increase understory productivity and diversity and to reduce the risk of severe wildfire. However, disturbances associated with treatments may favor invasion of nonnative species, and the severity of the disturbance may be related to the level of nonnative species establishment. We examined understory community composition, species richness, and plant cover responses to 3 stand-scale replicates of 4 different tree-thinning intensities. Restoration treatments altered the composition of the understory community regardless of thinning intensity. Understory richness and cover were highly variable among experimental blocks, but we observed strong trends of increasing richness and cover in the treated stands. Immediately following restoration treatments, nonnative species cover comprised 6% of the total cover where treatment-induced disturbances were the greatest. However, the initial increase in nonnative species did not persist and was reduced by half 6 years after treatment. Plant community composition was still in flux by the sixth year after treatment, indicating that continued monitoring is necessary for evaluating whether restoration targets are maintained over time

Ecosystem restoration: Final report for Assistance Agreement No. PAA 017002, Task Order No. AAW040001

The Restoration of Ecosystem Health in Southwest Forests project was initiated in 1995 to develop the scientific basis for ecological restoration of southwestern forests and woodlands at operational, landscape scales. The majority of the work has been focused in the Greater Mount Trumbull Ecosystem within the Grand Canyon/Parashant National Monument. This innovative collaboration between Department of Interior (BLM, NPS, BIA), state (Northern Arizona University, Game and Fish, State Forestry) has resulted in one of the foremost development and application sites for designing, implementing, monitoring, and evaluating restoration-based hazardous fuel reduction and ecological restoration sites in the Intermountain West. The work described in this report represents an expansion and enhancement of these collaborative partnerships. This report represents work completed in the four project areas: pinyon-juniper restoration, pinyon-juniper herbaceous revegetation, cheatgrass abatement and monitoring, and ponderosa pine restoration

Risk factors for human brucellosis in northern Tanzania

Little is known about the epidemiology of human brucellosis in sub-Saharan Africa. This hampers prevention and control efforts at the individual and population levels. To evaluate risk factors for brucellosis in northern Tanzania, we conducted a study of patients presenting with fever to two hospitals in Moshi, Tanzania. Serum taken at enrollment and at 4–6 week follow-up was tested by Brucella microagglutination test. Among participants with a clinically compatible illness, confirmed brucellosis cases were defined as having a ≥ 4-fold rise in agglutination titer between paired sera or a blood culture positive for Brucella spp., and probable brucellosis cases were defined as having a single reciprocal titer ≥ 160. Controls had reciprocal titers &lt; 20 in paired sera. We collected demographic and clinical information and administered a risk factor questionnaire. Of 562 participants in the analysis, 50 (8.9%) had confirmed or probable brucellosis. Multivariable analysis showed that risk factors for brucellosis included assisting goat or sheep births (Odds ratio [OR] 5.9, 95% confidence interval [CI] 1.4, 24.6) and having contact with cattle (OR 1.2, 95% CI 1.0, 1.4). Consuming boiled or pasteurized dairy products was protective against brucellosis (OR 0.12, 95% CI 0.02, 0.93). No participants received a clinical diagnosis of brucellosis from their healthcare providers. The under-recognition of brucellosis by healthcare workers could be addressed with clinician education and better access to brucellosis diagnostic tests. Interventions focused on protecting livestock keepers, especially those who assist goat or sheep births, are needed

Incidence of human brucellosis in the Kilimanjaro Region of Tanzania in the periods 2007-2008 and 2012-2014

Background: Brucellosis causes substantial morbidity among humans and their livestock. There are few robust estimates of the incidence of brucellosis in sub-Saharan Africa. Using cases identified through sentinel hospital surveillance and health care utilization data, we estimated the incidence of brucellosis in Moshi Urban and Moshi Rural Districts, Kilimanjaro Region, Tanzania, for the periods 2007–2008 and 2012–2014. Methods: Cases were identified among febrile patients at two sentinel hospitals and were defined as having either a 4-fold increase in Brucella microscopic agglutination test titres between acute and convalescent serum or a blood culture positive for Brucella spp. Findings from a health care utilization survey were used to estimate multipliers to account for cases not seen at sentinel hospitals. Results: Of 585 patients enrolled in the period 2007–2008, 13 (2.2%) had brucellosis. Among 1095 patients enrolled in the period 2012–2014, 32 (2.9%) had brucellosis. We estimated an incidence (range based on sensitivity analysis) of brucellosis of 35 (range 32–93) cases per 100 000 persons annually in the period 2007–2008 and 33 (range 30–89) cases per 100 000 persons annually in the period 2012–2014. Conclusions: We found a moderate incidence of brucellosis in northern Tanzania, suggesting that the disease is endemic and an important human health problem in this area

High-resolution profiling of homing endonuclease binding and catalytic specificity using yeast surface display

Experimental analysis and manipulation of protein–DNA interactions pose unique biophysical challenges arising from the structural and chemical homogeneity of DNA polymers. We report the use of yeast surface display for analytical and selection-based applications for the interaction between a LAGLIDADG homing endonuclease and its DNA target. Quantitative flow cytometry using oligonucleotide substrates facilitated a complete profiling of specificity, both for DNA-binding and catalysis, with single base pair resolution. These analyses revealed a comprehensive segregation of binding specificity and affinity to one half of the pseudo-dimeric interaction, while the entire interface contributed specificity at the level of catalysis. A single round of targeted mutagenesis with tandem affinity and catalytic selection steps provided mechanistic insights to the origins of binding and catalytic specificity. These methods represent a dynamic new approach for interrogating specificity in protein–DNA interactions

Expanding LAGLIDADG endonuclease scaffold diversity by rapidly surveying evolutionary sequence space

LAGLIDADG homing endonucleases (LHEs) are a family of highly specific DNA endonucleases capable of recognizing target sequences ∼20 bp in length, thus drawing intense interest for their potential academic, biotechnological and clinical applications. Methods for rational design of LHEs to cleave desired target sites are presently limited by a small number of high-quality native LHEs to serve as scaffolds for protein engineering—many are unsatisfactory for gene targeting applications. One strategy to address such limitations is to identify close homologs of existing LHEs possessing superior biophysical or catalytic properties. To test this concept, we searched public sequence databases to identify putative LHE open reading frames homologous to the LHE I-AniI and used a DNA binding and cleavage assay using yeast surface display to rapidly survey a subset of the predicted proteins. These proteins exhibited a range of capacities for surface expression and also displayed locally altered binding and cleavage specificities with a range of in vivo cleavage activities. Of these enzymes, I-HjeMI demonstrated the greatest activity in vivo and was readily crystallizable, allowing a comparative structural analysis. Taken together, our results suggest that even highly homologous LHEs offer a readily accessible resource of related scaffolds that display diverse biochemical properties for biotechnological applications

A Reappraisal of Children’s ‘Potential’

What does it mean for a child to fulfil his or her potential? This article explores the contexts and implications of the much-used concept of potential in educational discourses. We claim that many of the popular, political and educational uses of the term in relation to childhood have a problematic blind spot: interpersonality, and the necessary coexistence for the concept to be receivable of all children’s ‘potentials’. Rather than advocating abandoning the term—a futile gesture given its emotive force—we argue that the concept of children’s potential must be profoundly rethought to be workable as a philosophical notion in education. In an era marked by the unspoken assumption that ‘unlimited potential’ is always a good thing, we argue that it might be necessary to think about the limitations of the notion of individual potential; namely, the moment when it comes into contact with other people’s projects. We propose a conceptualisation of potential as the negotiated, situated, ever-changing creation of a group of individuals, in a process marked by conflict, and which remains essentially difficult.This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s11217-016-9508-