Above-ground biomass and productivity in a rain forest of eastern South America

Abstract: The dynamics of tropical forest woody plants was studied at the Nouragues Field Station, central French Guiana. Stem density, basal area, above-ground biomass and above-ground net primary productivity, including the contribution of litterfall, were estimated from two large permanent census plots of 12 and 10 ha, established on contrasting soil types, and censused twice, first in 1992¿1994, then again in 2000¿2002. Mean stem density was 512 stems ha¿1 and basal area, 30m2 ha¿1. Stem mortality rate ranged between 1.51% and 2.06% y¿1. In both plots, stem density decreased over the study period. Using a correlation between wood density and wood hardness directly measured by a Pilodyn wood tester,we found that the mean wood densitywas 0.63 g cm¿3, 12% smaller than the mean of wood density estimated from the literature values for the species occurring in our plot. Above-ground biomass ranged from 356 to 398Mgha¿1 (oven-dry mass), and it increased over the census period. Leaf biomass was 6.47Mg ha¿1. Our total estimate of aboveground net primary productivity was 8.81 MgC ha¿1 y¿1 (in carbon units), not accounting for loss to herbivory, branchfalls, or biogenic volatile organic compounds, whichmay altogether account for an additional 1MgC ha¿1 y¿1. Coarse wood productivity (stem growth plus recruitment) contributed to 4.16 MgC ha¿1 y¿1. Litterfall contributed to 4.65MgC ha¿1 y¿1 with 3.16 MgC ha¿1 y¿1 due to leaves, 1.10 MgC ha¿1 y¿1 to twigs, and 0.39MgC ha¿1 y¿1 to fruits and flowers. The increase in above-ground biomass for both trees and lianas is consistentwith the hypothesis of a shift in the functioning of Amazonian rain forests driven by environmental changes, although alternative hypotheses such as a recovery from past disturbances cannot be ruled out at our site, as suggested by the observed decrease in stem density. Key Words: above-ground biomass, carbon, French Guiana, net primary productivity, tropical fores

Gasheer gemeenskappe en mededingende aansoeke vir prospekteerregte ingevolge die “Mineral and Petroleum Resources Development Act” 28 of 2002

Die verskillende bepalings van die “Mineral and Petroleum Resources Development Act” 28 of 2002 (“die wet”) omtrent die toekenning van gewone prospekteerregte of ’n preferente regte om te prospekeer word in hierdie bydrae bespreek. ’n Gewone prospekteerreg word deur die Minister, by aansoek aan ’n applikant, toegeken indien aan die vereistes van artikel 17 van die Wet voldoen word. Artikel 104(1) van die Wet daarenteen maak voorsiening vir die aansoek deur en toekenning van ’n preferente propekteerreg aan ’n tradisionele gemeenskap (soos omskryf in die wet) om op gemeenskapgrond te prospekteer. Hierdie bepalings het die grondslag gevorm van ’n ongeraporteerde beslissing van die Transvaalse Afdeling van die Hooggeregshof in Bengwenyama Minerals (Pty) Ltd v Genorah Resources (Pty) Ltd (39808/2007 (TPD) (18-11-2008) Die beslissing het gehandel het oor die bepaling van regsvoorkeur by mededingende prospekteeraansoeke wat na mekaar ten aansien van die Bengwenyama tradisionele gemeenskapsgrond ingedien is. ’n Poging is in die saak aangewend om ex post facto die een prospekteeraansoek in te klee as ’n aansoek vir ’n preferente prospekteerreg deur die tradisionele gemeneenskap. Daar word geargumeenteer dat die hof se beslissing rakende die verskil en verhouding tussen die twee soorte prospekteerregte en die toepassing van die “first come, first served principle” ingevolge artikel 9(1)(b) Wet juis was. Daar word voorts aangevoer dat die feite van die Bengwenyama Minerals beslissing die tekortkoming van die huidige artikel 104 van die Wet, om die belange van ’n tradisionele gemeenskap te beskerm, aantoon indien iemand anders aansoek doen vir ’n gewone propekteerreg. Daar word ook uitgewys dat die voorgestelde 2008 wysigings van die Wet ook nie ver genoeg strek om deelname in prospektering en benutting van mineraalbronne deur ’n tradisionele gemeenskap te verseker nie. Die slotsom word bereik dat die huidige wetgewing dringend gewysig behoort te word om die belange van tradisionele gemeenskappe te beskerm.http://www.dejure.up.ac.za/nf201

Expropriation of "unused old order rights" by the MPRDA : you have lost it! : Agri SA v Minister of Minerals and Energy (Centre for Applied Legal Studies as amicus curiae) [2011] 3 All SA 296 (GNP)

No abstract available.http://www.lexisnexis.co.z

Pancreatic fistulae after pancreatic resections for neuroendocrine tumours compared with resections for other lesions

AbstractBackgroundResection for pancreatic neuroendocrine tumours (PNET) is suggested to be associated with an increased risk of a post-operative pancreatic fistula (POPF). The aim of this study was to describe morbidity after resections for PNET, focusing on POPF. Outcomes were compared with resections for other lesions.MethodsPatients undergoing an elective pancreatic resection during a 12-year period were retrospectively analysed. Morbidity was defined according to the International Study Group of Pancreatic Surgery (ISGPS) definitions.ResultsEighty-eight out of 832 patients (10.6%) underwent a resection for PNET. Atypical pancreatic resections (enucleation and central pancreatectomy) and distal pancreatectomies were more frequently performed for PNET. The POPF rate was 22.7% in patients operated for PNET compared with 17.2% in other patients (P = 0.200). In univariate analysis, body mass index (BMI), pancreatic duct diameter, somatostatin analogue administration, type of resection and type of pathology were associated with a POPF. In multivariate analysis, BMI, a pancreatic duct diameter <3 mm and central pancreatectomy remained independent risk factors [odds ratio (OR) 1.93, 95% confidence interval (CI) 1.22–3.07 and OR 3.04, 95% CI 1.05–8.82, respectively].ConclusionsHigh rates of POPF were found in patients operated for PNET. However, this was mainly owing to the fact that atypical resections, known to be associated with a higher fistula rate, were performed more frequently in these patients

Maccsand (Pty) Ltd v City of Cape Town 2012 (4) SA 181 (CC)

The Maccsand series of cases started with an application by the City of Cape Town in the High Court for an order interdicting and restraining Maccsand (Pty) Ltd (hereafter Maccsand) from conducting mining activities until the authorisations in terms of the (Western Cape) Land Use Planning Ordinance 15 of 1985 had been granted. Maccsand and the Minister of Mineral Resources (hereafter the Minister) lodged an appeal in Maccsand (Pty) Ltd and Another v City of Cape Town, and Maccsand eventually approached the Constitutional Court in Maccsand (Pty) Ltd v City of Cape Town for relief.http://www.puk.ac.za/fakulteite/regte/per/index.htmlam201

Colloquium: Mechanical formalisms for tissue dynamics

The understanding of morphogenesis in living organisms has been renewed by tremendous progressin experimental techniques that provide access to cell-scale, quantitative information both on theshapes of cells within tissues and on the genes being expressed. This information suggests that ourunderstanding of the respective contributions of gene expression and mechanics, and of their crucialentanglement, will soon leap forward. Biomechanics increasingly benefits from models, which assistthe design and interpretation of experiments, point out the main ingredients and assumptions, andultimately lead to predictions. The newly accessible local information thus calls for a reflectionon how to select suitable classes of mechanical models. We review both mechanical ingredientssuggested by the current knowledge of tissue behaviour, and modelling methods that can helpgenerate a rheological diagram or a constitutive equation. We distinguish cell scale ("intra-cell")and tissue scale ("inter-cell") contributions. We recall the mathematical framework developpedfor continuum materials and explain how to transform a constitutive equation into a set of partialdifferential equations amenable to numerical resolution. We show that when plastic behaviour isrelevant, the dissipation function formalism appears appropriate to generate constitutive equations;its variational nature facilitates numerical implementation, and we discuss adaptations needed in thecase of large deformations. The present article gathers theoretical methods that can readily enhancethe significance of the data to be extracted from recent or future high throughput biomechanicalexperiments.Comment: 33 pages, 20 figures. This version (26 Sept. 2015) contains a few corrections to the published version, all in Appendix D.2 devoted to large deformation

Percutaneous Preoperative Biliary Drainage for Resectable Perihilar Cholangiocarcinoma: No Association with Survival and No Increase in Seeding Metastases

Background: Endoscopic biliary drainage (EBD) and percutaneous transhepatic biliary drainage (PTBD) are both used to resolve jaundice before surgery for perihilar cholangiocarcinoma (PHC). PTBD has been associated with seeding metastases. The aim of this study was to compare overall survival (OS) and the incidence of initial seeding metastases that potentially influence survival in patients with preoperative PTBD versus EBD. Methods: Between 1991 and 2012, a total of 278 patients underwent preoperative biliary drainage and resection of PHC at 2 institutions in the Netherlands and the United States. Of these, 33 patients were excluded for postoperative mortality. Among the 245 included patients, 88 patients who underwent preoperative PTBD (with or without previous EBD) were compared to 157 patients who underwent EBD only. Survival analysis was done with Kaplan–Meier and Cox regression with propensity score adjustment. Results: Unadjusted median OS was comparable between the PTBD group (35 months) and EBD-only group (41 months; P = 0.26). After adjustment for propensity score, OS between the PTBD group and EBD-only group was similar (hazard ratio, 1.05; 95 % confidence interval, 0.74–1.49; P = 0.80). Seeding metastases in the laparotomy scar occurred as initial recurrence in 7 patients, including 3 patients (3.4 %) in the PTBD group and 4 patients (2.7 %) in the EBD-only group (P = 0.71). No patient had an initial recurrence in percutaneous catheter tracts. Conclusions: The present study found no effect of PTBD on survival compared to patients with EBD and no increase in seeding metastases that developed as initial recurrence. These data suggest that PTBD can safely be used in preoperative management of PHC

Pituitary Adenylate Cyclase Activating Peptide (1-38) and its analog (Acetyl-[Ala15, Ala20] PACAP 38-polyamide) reverse methacholine airway hyperresponsiveness in rats

O objetivo deste estudo foi investigar funcionalmente e estruturalmente efeito broncodilatador do peptídeo ativador da adenilato ciclase pituitária (PACAP1-38) e da acetil-[Ala15, Ala20]PACAP 38-poliamida, potente análogo do PACAP-38, nos ratos desafiados pelo metacolina (MeCh). Ratos Wistar machos foram aleatoriamente divididos em cinco grupos. Grupos 1 e 2, inalando aerossóis de solução salina ou doses crescentes de MeCh (0,5, 1, 2,12, 4,25, 8,5, 17, 34 e 68 mg/L). Os outros grupos recebendo terbutalina (Terb) (250 µg/rato) (10-6M), PACAP-38 (50 µg/rato) (0.1 mM) ou análogo do PACAP-38 (50 µg/rato) associados a MeCh na dose de 4,25 mg/L. A resistência pulmonar total (RL) foi registrada antes e 2 min após a administração de Mech pelo equipamento pneumomultiteste. A administração MeCh induziu aumento significativo e dose dependente (pThe aim of this study was to investigate both functionally and structurally bronchodilator effects of Pituitary adenylate cyclase activating peptide (PACAP38) and acetyl-[Ala15, Ala20] PACAP38-polyamide, a potent PACAP38 analog, in rats challenged by methacholine (MeCh). Male Wistar rats were divided randomly into five groups. Groups 1 and 2 inhaled respectively aerosols of saline or increasing doses of MeCh (0.5, 1, 2.12, 4.25, 8.5, 17, 34 and 68mg/L). The other groups received terbutaline (Terb) (250 µg/rat) (10-6 M), PACAP38 (50 µg/rat) (0.1 mM) or PACAP38 analog (50 µg/rat) associated to MeCh from the dose of 4.25 mg/L. Total lung resistances (RL) were recorded before and 2 min after MeCh administration by pneumomultitest equipment. MeCh administration induced a significant and a dose-dependent increase (

The Clinical Variability of Maternally Inherited Diabetes and Deafness Is Associated with the Degree of Heteroplasmy in Blood Leukocytes

Context: Maternally inherited diabetes and deafness (MIDD) is a rare form of diabetes with a matrilineal transmission, sensorineural hearing loss, and macular pattern dystrophy due to an A to G transition at position 3243 of mitochondrial DNA (mtDNA) (m.3243A&gt;G). The phenotypic heterogeneity of MIDD may be the consequence of different levels of mutated mtDNA among mitochondria in a given tissue. Objective: The aim of the present study was thus to ascertain the correlation between the severity of the phenotype in patients with MIDD and the level of heteroplasmy in the blood leukocytes. Participants: The GEDIAM prospective multicenter register was initiated in 1995. Eighty-nine Europid patients from this register, with MIDD and the mtDNA 3243A&gt;G mutation, were included. Patients with MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes) or with mitochondrial diabetes related to other mutations or to deletions of mtDNA were excluded. Results: A significant negative correlation was found between levels of heteroplasmy and age of the patients at the time of sampling for molecular analysis, age at the diagnosis of diabetes, and body mass index. After adjustment for age at sampling for molecular study and gender, the correlation between heteroplasmy levels and age at the diagnosis of diabetes was no more significant. The two other correlations remained significant. A significant positive correlation between levels of heteroplasmy and HbA1c was also found and remained significant after adjustment for age at molecular sampling and gender. Conclusions: These results support the hypothesis that heteroplasmy levels are at least one of the determinants of the severity of the phenotype in MIDD. Heteroplasmy levels are at least one of the determinants of the severity of the phenotype of maternally inherited diabetes and deafness