926 resultados para Botanica : the illustrated A-Z of over 10,000 garden plants and how to cultivate them
Resumo:
L'indagine ha riguardato il profilo del vento nei primi 30 metri dello strato limite atmosferico stabile nell'ambito della teoria di similarità locale. Ad oggi, diversi esperimenti hanno confermato la validità della teoria per strati-limite su terreni livellati e superfici omogenee. Tali condizioni ideali sono però infrequenti nella realtà ed è perciò importante capire quali siano i limiti della similarità locale per strati-limite su terreni complessi e superfici disomogenee. Entrambe le condizioni sono presenti a Ny-Alesund (Svalbard, Norvegia) dove il Consiglio Nazionale delle Ricerche (CNR), nel 2009, ha installato una torre di 30 m, la Amudsen-Nobile Climate Change Tower (CCT), per lo studio dello strato-limite artico. Il lavoro di tesi ha riguardato misure di vento e turbolenza acquisite sulla CCT da maggio 2012 a maggio 2014. Il confronto tra le velocità del vento misurate dagli anemometri installati sulla CCT, ha rivelato criticità nel dato sonico manifestatesi con sovrastime sistematiche e maggiore erraticità rispetto alle misure provenienti dagli anemometri a elica. Un test condotto fra diversi metodi per il calcolo dei gradienti verticali della velocità del vento ha rivelato scarsa sensibilità dei risultati ottenuti al particolare metodo utilizzato. Lo studio ha riguardato i gradienti verticali adimensionali della velocità del vento nei primi 30-m dello strato limite stabile. Deviazioni significative tra i tra le osservazioni e i valori predetti dalla similarità locale sono state osservate in particolare per i livelli più distanti dal suolo e per valori crescenti del parametro di stabilità z/L (L, lunghezza di Obukhov locale). In particolare, si sono osservati gradienti adimensionali inferiori a quelli predetti dalle più usate relazioni di flusso-gradiente. Tali deviazioni, presenti perlopiù per z/L>0.1, sono state associate ad un effetto di accentuazione della turbolenza da parte delle irregolarità del terreno. Per condizioni meno stabili, z/L<0.1, scarti positivi tra i gradienti osservati e quelli attesi sono stati attribuiti alla formazione di strati limite interni in condizioni di vento dal mare verso la costa. Sono stati proposti diversi metodi per la stima dell'effetto della self-correlazione nella derivazione delle relazioni di flusso-gradiente, dovuta alla condivisione della variabile u*. La formula per il coefficiente lineare di self correlazione e le sue distribuzioni di probabilità empiriche sono state derivate e hanno permesso di stimare il livello di self-correlazione presente nel dataset considerato.
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OBJECTIVES: The present literature review conceptualises landscape as a health resource that promotes physical, mental, and social well-being. Different health-promoting landscape characteristics are discussed. METHODS: This article is based on a scoping study which represents a special kind of qualitative literature review. Over 120 studies have been reviewed in a five-step-procedure, resulting in a heuristic device. RESULTS: A set of meaningful pathways that link landscape and health have been identified. Landscapes have the potential to promote mental well-being through attention restoration, stress reduction, and the evocation of positive emotions; physical well-being through the promotion of physical activity in daily life as well as leisure time and through walkable environments; and social well-being through social integration, social engagement and participation, and through social support and security. CONCLUSION: This scoping study allows us to systematically describe the potential of landscape as a resource for physical, mental and social well-being. A heuristic framework is presented that can be applied in future studies, facilitating systematic and focused research approaches and informing practical public health interventions.
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Context: Endometriosis is characterized by the growth of ectopic endometrial tissue. Nerve fibers are frequently associated with ectopic lesions, and neurogenic inflammation may play a role in endometriosis. Objective: The purpose of this study was to determine the presence of tachykinin receptors in endometriotic lesions and the role of TNFα on their expression. Design: This study was an assessment of matching eutopic and ectopic endometrial tissue and peritoneal fluid from patients with endometriosis and an in vitro analysis of primary endometrial cells. Setting: The setting was a university hospital. Patients: Participants were premenopausal women undergoing laparoscopy. Interventions: Endometriotic lesions were removed surgically. Main Outcome Measures: Tachykinin mRNA (TACR1/2) and protein (neurokinin 1 receptor [NK1R]) expression in both eutopic and ectopic endometrial tissue from patients with endometriosis and the correlation to peritoneal fluid TNFα were measured. Primary endometrial epithelial and stromal cells were assessed in vitro to determine the induction of TACR1/2 and NK1R expression after TNFα treatment. Cell viability of endometrial stromal cells after substance P exposure was also assessed. Results: Expression of both TACR1 and TACR2 mRNA was significantly higher in the ectopic than in the eutopic tissue. Both TACR1 mRNA and NK1R protein expression was significantly correlated with peritoneal fluid TNFα, and in vitro studies confirmed that TNFα treatment induced both TACR1 mRNA and NK1R protein expression in endometrial stromal cells. In endometrial stromal cells, substance P treatment enhanced cell viability, which was inhibited by a specific NK1R antagonist. Conclusions: NK1R expression is induced in ectopic endometrial tissue by peritoneal TNFα. Induction of NK1R expression may permit endometriotic lesion maintenance via exposure to substance P.
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Seventy male lambs over 10 weeks of age were castrated using Burdizzo, rubber rings, or surgery to assess the acute and long-term effects of castration. All castrations were performed under local anaesthesia. The surgically castrated lambs were additionally sedated with xylazine and the sedation reversed with tolazoline. The frequency of abnormal postures and immediate behavioural responses indicated that surgically castrated lambs were most distressed; the lambs castrated using Burdizzo and rubber rings were not dissimilar to those of the control group. Between 1.5 and 9h after castration, signs of pain and distress were at a lower level in lambs anaesthetised with bupivacaine compared with those treated with lidocaine. Due to the markedly faster wound healing, Burdizzo castration seemed to be preferable (fewer signs of long-term pain) when compared to the rubber ring technique. It was concluded that local anaesthesia with bupivacaine, followed by the Burdizzo method is the preferable technique for the castration of lambs older than 10 weeks of age.
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BACKGROUND: Treatment of patients with attention deficit hyperactivity disorder (ADHD) with homeopathy is difficult. The Swiss randomised, placebo controlled, cross-over trial in ADHD patients (Swiss ADHD trial) was designed with an open-label screening phase prior to the randomised controlled phase. During the screening phase, the response of each child to successive homeopathic medications was observed until the optimal medication was identified. Only children who reached a predefined level of improvement participated in the randomised, cross-over phase. Although the randomised phase revealed a significant beneficial effect of homeopathy, the cross-over caused a strong carryover effect diminishing the apparent difference between placebo and verum treatment. METHODS: This retrospective analysis explores the screening phase data with respect to the risk of failure to demonstrate a specific effect of a randomised controlled trial (RCT) with randomisation at the start of the treatment. RESULTS: During the screening phase, 84% (70/83) of the children responded to treatment and reached eligibility for the randomised trial after a median time of 5 months (range 1-18), with a median of 3 different medications (range 1-9). Thirteen children (16%) did not reach eligibility. Five months after treatment start, the difference in Conners Global Index (CGI) rating between responders and non-responders became highly significant (p = 0.0006). Improvement in CGI was much greater following the identification of the optimal medication than in the preceding suboptimal treatment period (p < 0.0001). CONCLUSIONS: Because of the necessity of identifying an optimal medication before response to treatment can be expected, randomisation at the start of treatment in an RCT of homeopathy in ADHD children has a high risk of failure to demonstrate a specific treatment effect, if the observation time is shorter than 12 months.
Resumo:
BACKGROUND Of the approximately 2.4 million American women with a history of breast cancer, 43% are aged ≥ 65 years and are at risk for developing subsequent malignancies. METHODS Women from 6 geographically diverse sites included 5-year breast cancer survivors (N = 1361) who were diagnosed between 1990 and 1994 at age ≥ 65 years with stage I or II disease and a comparison group of women without breast cancer (N = 1361). Women in the comparison group were age-matched and site-matched to breast cancer survivors on the date of breast cancer diagnosis. Follow-up began 5 years after the index date (survivor diagnosis date or comparison enrollment date) until death, disenrollment, or through 15 years after the index date. Data were collected from medical records and electronic sources (cancer registry, administrative, clinical, National Death Index). Analyses included descriptive statistics, crude incidence rates, and Cox proportional hazards regression models for estimating the risk of incident malignancy and were adjusted for death as a competing risk. RESULTS Survivors and women in the comparison group were similar: >82% were white, 55% had a Charlson Comorbidity Index of 0, and ≥ 73% had a body mass index ≤ 30 kg/m(2) . Of all 306 women (N = 160 in the survivor group, N = 146 in the comparison group) who developed a first incident malignancy during follow-up, the mean time to malignancy was similar (4.37 ± 2.81 years vs 4.03 ± 2.76 years, respectively; P = .28), whereas unadjusted incidence rates were slightly higher in survivors (1882 vs 1620 per 100,000 person years). The adjusted hazard of developing a first incident malignancy was slightly elevated in survivors in relation to women in the comparison group, but it was not statistically significant (hazard ratio, 1.17; 95% confidence interval, 0.94-1.47). CONCLUSIONS Older women who survived 5 years after an early stage breast cancer diagnosis were not at an elevated risk for developing subsequent incident malignancies up to 15 years after their breast cancer diagnosis.