456 research outputs found

    Relationships between herbaceous diversity and biomass in two habitats in arid Mediterranean rangeland

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    Plant diversity patterns vary across the landscape. This study was conducted to answer the question: What is the pattern of species diversity (α and β) along an abstract productivity/cover gradient at two topographical positions (Wadi (a depression with overland flow) and hilltop) of a Mediterranean herbaceous plant community in Jordan? Results indicated that the less productive hilltop localities exhibited higher species richness than the more productive Wadi localities. Species richness exhibited a unimodal relationship with aboveground biomass within Wadis whereas a positive linear relationship was revealed for hilltops. Within Wadis, abundant species did not show a significant relationship with productivity while common and rare species showed a unimodal relationship. Within hilltops, abundant, common, and rare species showed a linear relationship with biomass. β-diversity, measured as species dissimilarity, showed significant negative relationship to biomass within hilltops, whereas a positive relationship was observed within Wadis. Wilson-Shmida index (βT) had a unimodal function with increased differences in productivity whereas Morisita-Horn index (Cmh) showed a reverse unimodal relationship. Examination of the species richness-biomass relationship among species groups (abundant, common, and rare) suggested that abundant species maybe more important on low productivity sites whereas common and rare species maybe more important on high productivity sites

    Changes in understory vegetation of a ponderosa pine forest in northern Arizona 30 years after a Wildfire

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    Wildland fires can cause shifts in understory species composition and production. Many studies have examined short-term changes in understory vegetation following a wildfire; however, very few long term studies are available. The objective of this study was to examine changes in understory (herb and shrub) species composition and production since the 1972 Rattle Burn wildfire on the Coconino National Forest near Flagstaff, Arizona. Understory species composition and production were originally sampled in 1972, 1974, and 1980 and were re-sampled during July and August of 2002 and 2003 on 30 plots in each of four sites: high severity burn, low severity burn, unburned site prescribed burned in 1977, and an unburned site. Repeated measures analysis was used to test for the effects of fire and time on species production. The effects of fire and time on species composition as well as species production were tested using Multi-Response Permutation Procedures (MRPP). A lingering effect of the Rattle Burn wildfire on the understory plant production and composition was revealed. Burned sites may have greater understory production as compared to unburned sites up to 30 years after a wildfire. However, species composition on burned sites is altered. A significant relationship between tree density and understory species composition and production was found for 1972, but no relationship was found for overstory parameters and understory species production and composition for 2003

    Loblolly Pine Growth Response to Mid-rotational Treatments in an Eastern Texas Plantation

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    The effects of mid-rotational treatments (herbicide, prescribed burn, combination of herbicide and burn, and fertilization) on growth of loblolly pine were evaluated. Five replicates were established in a split-plot experimental design with fertilizer treatments as the whole-plot factor and competition control treatments as the sub-plot factor. Growth response was measured (as change in diameter, total height, and volume) at 8 months and again 4 years after treatments were applied. Mid-rotational treatments failed to enhance diameter, height, and volume growth of loblolly pine. However, a small positive response of diameter growth to fertilization was detected. Height growth was not significantly affected by any treatment 8 months after application date, while it was slightly negatively affected by herbicide and the combination of herbicide and prescribed burning 4 years after application of treatments. In this study, no substantial positive growth response to mid-rotational treatments was detected. However, loblolly growth response may vary from site to site based on differences in soil type, soil condition, and competition level. In addition, associated factors such as seedling quality and planting method may greatly influence loblolly growth response to mid-rotational treatments

    Spatial Autocorrelation and Pseudoreplication in Fire Ecology

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    Fire ecologists face many challenges regarding the statistical analyses of their studies. Hurlbert (1984) brought the problem of pseudoreplication to the scientific community’s attention in the mid 1980’s. Now, there is a new issue in the form of spatial autocorrelation. Spatial autocorrelation, if present, violates the traditional statistical assumption of observational independence. What, if anything, can the fire ecology community do about this new problem? An understanding of spatial autocorrelation, and knowledge of available methods used to reduce the effect of spatial autocorrelation and pseudoreplication will greatly assist fire ecology researchers

    The impact of an educational course for swimming on free style swimming performance and life skills for deaf students

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    This study investigates the impact of an educational course for swimming on free style swimming performance and life skills for deaf students. Subjects were (10) male deaf students who were at-tended to swimming courses level (1) in the Faculty of Physical Education at the University of Jordan, with mean age of (M age = 20.4 SD =1.35). After completing the Life skills through swimming context scale (Bayyat et al., 2016) and practical pre-test of free style swimming skills performance, subjects executed both physical practice of the free style swimming skills performance during a pro-gram conceited of eighteen sessions, 3 sessions a week, for 6-weeks, 60 mints per session, and life skills development dialogues program which focused on certain life skills (Communications, team-work, self-confidence/self-Esteem, problem solving and decision-making/responsibility).After 6-weeks all subjects completed a post life skills questionnaire which measured the changes in their life skills level after learning the free style swimming skills performance, they also went through a post practical subjective performance evaluation post-test which measured their level of the free style swimming skills performance. Statistical analysis was processed by SPSS. The results showed significant differences between pre and post-test in life skills dimensions and significant differences between pre and post-test in free style swimming performance level for the subject of this study. In conclusions the educational course for swimming had a positive impact on free style swimming performance and on life skills for deaf students in the faculty of physical education at the University of Jordan

    Altered Composition of the Oral Microbiota in Depression Among Cigarette Smokers: A Pilot Study

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    Alterations in the oral microbiota composition may influence mental health. However, linkages between compositional changes in the oral microbiota and their role in mental health among cigarette smokers remain largely unknown. In this study, we used shotgun metagenomics data for the oral microbiome of 105 participants. The data showed Bacteroidota, Fusobacteriota, Firmicutes, Proteobacteria, and Actinobacteria to be the most abundant phyla; Streptococcus, Haemophilus D, and Veillonella are the most abundant genera. Then, we clustered our subjects into avoidance and activation groups based on the behavioral activation for depression scale (BADS). Interestingly, the avoidance group exhibited a higher oral microbiome richness and diversity (alpha diversity). Differential abundance testing between BADS avoidance and activation groups showed the phyla Bacteroidota (effect size 0.5047, q = 0.0037), Campylobacterota (effect size 0.4012, q = 0.0276), Firmicutes A (effect size 0.3646, q = 0.0128), Firmicutes I (effect size 0.3581, q = 0.0268), and Fusobacteriota (effect size 0.6055, q = 0.0018) to be significantly increased in the avoidance group, but Verrucomicrobiota (effect size−0.6544, q = 0.0401), was found to be significantly decreased in the avoidance risk group. Network analysis of the 50 genera displaying the highest variation between both groups identified Campylobacter B, Centipeda, and Veillonella as hub nodes in the avoidance group. In contrast, Haemophilus and Streptococcus were identified as hub nodes in the activation group. Next, we investigated functional profiles of the oral microbiota based on BADS avoidance and activation groups and found Lysine degradations pathway was significantly enriched between both groups (ANCOM-BC, q = 0.0692). Altogether, we provide evidence for the presence of depression-related changes in the oral microbiota of smokers and possible functional contribution. The identified differences provide new information to enrich our understanding of oral microbiota-brain axis interplay and their potential impact on mental health

    Measurement of the WZ production cross section in pp collisions at root s=7 and 8 TeV and search for anomalous triple gauge couplings at root s=8 TeV

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    Peer reviewe

    Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

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    Background: Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. // Methods: We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung's disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. // Findings: We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung's disease) from 264 hospitals (89 in high-income countries, 166 in middle-income countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in low-income countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. // Interpretation: Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between low-income, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

    Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

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    Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P &lt; 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

    Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

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    Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis
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