scholarly journals Sagebrush steppe recovery after fire varies by development phase of Juniperus occidentalis woodland

2014 ◽  
Vol 23 (1) ◽  
pp. 117 ◽  
Author(s):  
Jonathan D. Bates ◽  
Robert N. Sharp ◽  
Kirk W. Davies

Woodland ecosystems of the world have been changed by land use demands, altered fire regimes, invasive species and climate change. Reduced fire frequency is recognised as a main causative agent for Pinus–Juniperus L. (piñon–juniper) expansion in North American woodlands. Piñon–juniper control measures, including prescribed fire, are increasingly employed to restore sagebrush steppe communities. We compared vegetation recovery following prescribed fire on Phase 2 (mid-succession) and Phase 3 (late-succession) Juniperus occidentalis Hook. (western juniper) woodlands in Oregon. The herbaceous layer on Phase 2 sites was comprised of native perennial and annual vegetation before and after fire. On Phase 3 sites the herbaceous layer shifted from native species to dominance by invasive Bromus tectorum L. (cheatgrass). After fire, shrubs on Phase 2 sites were comprised of sprouting species and Ceanothus velutinus Dougl. (snowbrush). On Phase 3 woodland sites the shrub layer was dominated by C. velutinus. The results suggest that Phase 2 sites have a greater likelihood of recovery to native vegetation after fire and indicate that sites transitioning from Phase 2 to Phase 3 woodlands cross a recovery threshold where there is a greater potential for invasive weeds, rather than native vegetation, to dominate after fire.

2018 ◽  
Vol 86 (08) ◽  
pp. 456-457
Keyword(s):  
Phase 2 ◽  
Phase 3 ◽  

Die Blockade von Serotoninrezeptoren, insbesondere des Serotonin-Rezeptortyps 5-HT6, als Zusatztherapie in Kombination mit Cholinesterasehemmer, hat in experimentellen Versuchen sowie in einer Phase-2-Studie positive Effekte bei Demenz gezeigt. Im Rahmen eines Phase-3 Entwicklungsprogramms wurde nun die Effektivität des selektiven Serotoninrezeptor-Antagonisten Idalopirdin bei leichter bis mittelschwerer Alzheimer Demenz geprüft.


2013 ◽  
Vol 5 (1) ◽  
Author(s):  
Abdul Hasan Saragih

This classroom research was conducted on the autocad instructions to the first grade of mechinary class of SMK Negeri 1 Stabat aiming at : (1) improving the student’ archievementon autocad instructional to the student of mechinary architecture class of SMK Negeri 1 Stabat, (2) applying Quantum Learning Model to the students of mechinary class of SMK Negeri 1 Stabat, arising the positive response to autocad subject by applying Quantum Learning Model of the students of mechinary class of SMK Negeri 1 Stabat. The result shows that (1) by applying quantum learning model, the students’ achievement improves significantly. The improvement ofthe achievement of the 34 students is very satisfactory; on the first phase, 27 students passed (70.59%), 10 students failed (29.41%). On the second phase 27 students (79.41%) passed and 7 students (20.59%) failed. On the third phase 30 students (88.24%) passed and 4 students (11.76%) failed. The application of quantum learning model in SMK Negeri 1 Stabat proved satisfying. This was visible from the activeness of the students from phase 1 to 3. The activeness average of the students was 74.31% on phase 1,81.35% on phase 2, and 83.63% on phase 3. (3) The application of the quantum learning model on teaching autocad was very positively welcome by the students of mechinary class of SMK Negeri 1 Stabat. On phase 1 the improvement was 81.53% . It improved to 86.15% on phase 3. Therefore, The improvement ofstudent’ response can be categorized good.


2017 ◽  
Vol 1 ◽  
pp. s49
Author(s):  
Linda Stein Gold ◽  
Sunil Dhawan ◽  
Jonathan Weiss ◽  
Zoe D Draelos ◽  
Herman Ellman

Abstract Not Available


2010 ◽  
Vol 9 (4) ◽  
pp. 214-219
Author(s):  
Robyn J. Barst

Drug development is the entire process of introducing a new drug to the market. It involves drug discovery, screening, preclinical testing, an Investigational New Drug (IND) application in the US or a Clinical Trial Application (CTA) in the EU, phase 1–3 clinical trials, a New Drug Application (NDA), Food and Drug Administration (FDA) review and approval, and postapproval studies required for continuing safety evaluation. Preclinical testing assesses safety and biologic activity, phase 1 determines safety and dosage, phase 2 evaluates efficacy and side effects, and phase 3 confirms efficacy and monitors adverse effects in a larger number of patients. Postapproval studies provide additional postmarketing data. On average, it takes 15 years from preclinical studies to regulatory approval by the FDA: about 3.5–6.5 years for preclinical, 1–1.5 years for phase 1, 2 years for phase 2, 3–3.5 years for phase 3, and 1.5–2.5 years for filing the NDA and completing the FDA review process. Of approximately 5000 compounds evaluated in preclinical studies, about 5 compounds enter clinical trials, and 1 compound is approved (Tufts Center for the Study of Drug Development, 2011). Most drug development programs include approximately 35–40 phase 1 studies, 15 phase 2 studies, and 3–5 pivotal trials with more than 5000 patients enrolled. Thus, to produce safe and effective drugs in a regulated environment is a highly complex process. Against this backdrop, what is the best way to develop drugs for pulmonary arterial hypertension (PAH), an orphan disease often rapidly fatal within several years of diagnosis and in which spontaneous regression does not occur?


Stroke ◽  
2020 ◽  
Vol 51 (11) ◽  
pp. 3440-3451
Author(s):  
Steven J. Warach ◽  
Adrienne N. Dula ◽  
Truman J. Milling

Tenecteplase is a fibrinolytic drug with higher fibrin specificity and longer half-life than the standard stroke thrombolytic, alteplase, permitting the convenience of single bolus administration. Tenecteplase, at 0.5 mg/kg, has regulatory approval to treat ST-segment–elevation myocardial infarction, for which it has equivalent 30-day mortality and fewer systemic hemorrhages. Investigated as a thrombolytic for ischemic stroke over the past 15 years, tenecteplase is currently being studied in several phase 3 trials. Based on a systematic literature search, we provide a qualitative synthesis of published stroke clinical trials of tenecteplase that (1) performed randomized comparisons with alteplase, (2) compared different doses of tenecteplase, or (3) provided unique quantitative meta-analyses. Four phase 2 and one phase 3 study performed randomized comparisons with alteplase. These and other phase 2 studies compared different tenecteplase doses and effects on early outcomes of recanalization, reperfusion, and substantial neurological improvement, as well as symptomatic intracranial hemorrhage and 3-month disability on the modified Rankin Scale. Although no single trial prospectively demonstrated superiority or noninferiority of tenecteplase on clinical outcome, meta-analyses of these trials (1585 patients randomized) point to tenecteplase superiority in recanalization of large vessel occlusions and noninferiority in disability-free 3-month outcome, without increases in symptomatic intracranial hemorrhage or mortality. Doses of 0.25 and 0.4 mg/kg have been tested, but no advantage of the higher dose has been suggested by the results. Current clinical practice guidelines for stroke include intravenous tenecteplase at either dose as a second-tier option, with the 0.25 mg/kg dose recommended for large vessel occlusions, based on a phase 2 trial that demonstrated superior recanalization and improved 3-month outcome relative to alteplase. Ongoing randomized phase 3 trials may better define the comparative risks and benefits of tenecteplase and alteplase for stroke thrombolysis and answer questions of tenecteplase efficacy in the >4.5-hour time window, in wake-up stroke, and in combination with endovascular thrombectomy.


2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 196-197
Author(s):  
Woo Jung Seok ◽  
Je min Ahn ◽  
Jing Hu ◽  
Dexin Dang ◽  
Yanjiao Li ◽  
...  

Abstract The objective of this study was to evaluate the effects of dietary supplementation of coated omega-3 fatty acid (n-3 CFA) by corn cob power silica on performance of weaning pigs. A total of 200 weaned pigs [(Landrace x Yorkshire) x Duroc, average initial body weight at 6.97 ± 1.22 kg] were randomly assigned to four experimental treatments in a 6-week experiment in 3 phases as follows: CON, basal diet; 2) 0.3CFA, CON + phase 1(0.3% n-3CFA), phase 2(0.2% n-3CFA), phase 3(0.1% n-3CFA); 3) 0.6CFA, CON + phase 1(0.6% n-3CFA), phase 2(0.4% n-3CFA), phase 3(0.2% n-3CFA); 4) 0.9CFA, CON + phase 1(0.9% n-3CFA), phase 2(0.6% n-3CFA), phase 3 (0.3% n-3CFA). Each treatment had 10 replicates with 5 pigs (three gilts and two barrows) per replicate. The data were analyzed using the GLM procedure of SAS as a randomized complete block design. Pen served as the experimental unit. Linear, quadratic and cubic polynomial contrasts were used to examine effect of dietary treatment with coated n-3FA in the basal diet. Variability in the data was expressed as the standard error of means and P< 0.05 was considered to statistically significant. Increasing the level of n-3CFA in the diet linearly increased ADG and G/F of pigs (Table 1). Increasing the level of n-3CFA showed a linear increment in the digestibility of DM (83.59, 84.38, 85.13, 85.89 %) whereas nitrogen digestibility (81.79, 82.38, 82.96, 83.64 %) showed a trend (linear effect, p=0.0594) at the end of experiment. The fecal lactobacillus count was increased (7.22, 7.27, 7.33, 7.35 log10cfu/g) with the increase in the supplemental level of n-3CFA (linear effect; p< 0.05). However, there were no differences in the concentration of serum haptoglobin, or fecal E. coli, Clostridium and Salmonella counts despite the increase in n-3CFA levels in the diet. Supplementation of the diet with coated n-3 fatty acids positively affected growth performance and digestibility of dry matter and nitrogen, and enhanced the count of lactobacillus in weaning pigs.


2021 ◽  
Author(s):  
Natalia F Versiani ◽  
Larissa L Bailey ◽  
Nielson Pasqualotto ◽  
Thiago F Rodrigues ◽  
Roberta M Paolino ◽  
...  

Abstract The drastic reduction of the Brazilian Cerrado has transformed this savanna hotspot into vast swaths of commodity-based agriculture fields, mainly soybean, sugarcane, and beef-production pasturelands. The resulting habitat loss and fragmentation are the principal factors underlying population decline of native species inhabiting the Cerrado, particularly those with a high demand for space, low population density, and specialized diet, such as the endangered giant anteater (Myrmecophaga tridactyla). Although the species has been studied in protected areas, we know much less about its ability to endure in disturbed landscapes. Here, we analyzed camera-trapping data to estimate a proxy of habitat use (ψ^; occupancy) and detection probabilities of the giant anteater, identifying environmental covariates influencing these parameters in landscapes with intensive agriculture and commercial forestry. We found this species using about half of the study area (model average ψ^ = 0.51, CI = 0.40–0.62), with two predictors strongly influencing habitat use: protected areas and unpaved roads. In turn, detection probability correlates positively with area of open Cerrado and negatively with area of settlements. The species is more likely to use unpaved roads inside protected areas (ψ^ = 0.90, CI = 0.47–0.75), compared to off road sites in the surrounding areas (ψ^ = 0.19, CI = 0.10–0.34). Our findings indicate that giant anteaters are dependent on nature reserves and native vegetation areas existing on private properties, whose protection is regulated by the Brazilian Native Vegetation Protection Law. Given the relative paucity of state-owned protected areas in the Brazilian Cerrado, increasing the adherence of rural owners to this law is, therefore, key for the conservation of the giant anteater. The intense use of unpaved roads might reflect travelling and/or foraging optimization, a behavioral response that, nevertheless, may compound this species’ susceptibility to suffer mortality from roadkill.


Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 759
Author(s):  
Vetriselvi Sampath ◽  
Dong Heon Baek ◽  
Sureshkumar Shanmugam ◽  
In Ho Kim

This experiment was performed to examine the hypothesis that blood plasma (BP) with yeast (Saccharomyces cerevisiae) supplement in the diet of weaning pigs could provoke the growth performance, nutrient digestibility, fecal microbial, and reduce harmful gas excretion. A total of one hundred and eighty healthy piglets were taken and assigned (complete random blocks) to three dietary treatments as: Phase 1: Treatment (TRT) 1-6% BP; TRT 2-3% BP + 3% yeast; TRT 3-6% yeast. Phase 2: TRT 1-3%; BP., TRT 2-1.5% BP + 1.5% yeast; TRT 3- 3% yeast. Phase 3: TRT 1- Control (CON) (Basal diet); TRT 2- CON; TRT 3- CON for six- weeks. Each treatment had twelve replicates and five (three gilts and two barrows) pigs per pen. Dietary inclusion of BP with yeast supplementation significantly increased the body weight of piglets during phase 2 (p = 0.003) and phase 3 (p = 0.032). In addition, TRT2 group piglets had a significant improvement in average daily gain at the end of each phase and overall (p = 0.047, 0.025, 0.018 and 0.012, respectively). At phase 3, TRT2 group piglets showed a significant improvement on nutrient digestibility of dry matter (p = 0.012) and nitrogen (p = 0.040). The fecal microbiota of TRT2 group piglets showed a tendency to increase the number of Lactobacillus counts at phase 1 (p = 0.07) and phase 2 (p = 0.06) as well as, a significant improvement at phase 3 (p = 0.021). In addition, TRT2 group piglets had trend to decrease NH3 (p = 0.074) and H2S (p = 0.069) during phase 2, and significantly reduced NH3 (p = 0.038) and H2S (p = 0.046) at phase 3. However, the fecal score of piglets remains unaffected during the entire trial. At the end of phase 1 piglets’ IgG (p = 0.008) was significantly increased with the inclusion of BP with yeast supplementation. Based on the positive effects on body weight, average daily gain, nutrient digestibility, Lactobacillus count, and reduced gas emission, we suggest that dietary supplement with BP and yeast in the diet of weaned piglet could serve as an excellent alternative to antibiotics growth promoters.


2011 ◽  
Vol 2011 ◽  
pp. 1-13 ◽  
Author(s):  
Danae Maniatis ◽  
Yadvinder Malhi ◽  
Laurent Saint André ◽  
Danilo Mollicone ◽  
Nicolas Barbier ◽  
...  

In the context of the adoption at the 16th Conference of the Parties in 2010 on the REDD+ mitigation mechanism, it is important to obtain reliable data on the spatiotemporal variation of forest carbon stocks and changes (called Emission Factor, EF). A re-occurring debate in estimating EF for REDD+ is the use of existing field measurement data. We provide an assessment of the use of commercial logging inventory data and ecological data to estimate a conservative EF (REDD+ phase 2) or to report on EF following IPCC Guidance and Guidelines (REDD+ phase 3). The data presented originate from five logging companies dispersed over Gabon, totalling 2,240 plots of 0.3 hectares.We distinguish three Forest Types (FTs) in the dataset based on floristic conditions. Estimated mean aboveground biomass (AGB) in the FTs ranges from 312 to 333 Mg ha−1. A 5% accuracy is reached with the number of plots put in place for the FTs and a low sampling uncertainty obtained (± 10 to 13 Mg ha−1). The data could be used to estimate a conservative EF in REDD+ phase 2 and only partially to report on EF following tier 2 requirements for a phase 3.


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