How persistent are the impacts of logging roads on Central African forest vegetation?

Logging roads can trigger tropical forest degradation by reducing the integrity of the ecosystem and providing access for encroachment. Therefore, road management is crucial in reconciling selective logging and biodiversity conservation. Most logging roads are abandoned after timber harvesting; however, little is known about their long-term impacts on forest vegetation and accessibility, especially in Central Africa. In 11 logging concessions in the Congo Basin, we field-sampled a chronosequence of roads that, judging from satellite images, had been abandoned between 1985 and 2015. We assessed recovery of timber resources, tree diversity and above-ground biomass in three zones: the road track, the road edge (where forest had been cleared during road construction) and the adjacent logged forest. The density of commercial timber species <15 cm d.b.h. was almost three times higher in the road track (321 individuals ha−1) and edge (267) than in the logged adjacent forest (97). Over time, tree species diversity converged to a comparable level between roads and adjacent forests, along with an increase in canopy closure. The average width of forest clearing for road construction was 20 m, covering a total 0·76% of the forest area inside concessions. After 15 years following abandonment, road tracks had recovered 24 Mg ha−1 of above-ground woody biomass, which was 6% of that in the adjacent forest, while road edges had accumulated 167 Mg ha−1 (42%). Ten years after abandonment, roads were no longer penetrable by poachers on motorcycles. An exotic herb species was fully replaced by dominant Marantaceae that have even higher abundance in the adjacent forest. • Synthesis and applications. Our evidence of vegetation recovery suggests that logging roads are mostly transient elements in the forest landscapes. However, given the slow recovery of biomass on abandoned road tracks, we advocate both reducing the width of forest clearing for road construction and reopening old logging roads for future harvests, rather than building new roads in intact forests. Road edges seem suitable for post-logging silviculture which needs to be assisted by removing dominant herbs during the early years after abandonment while the road track is still accessible. (Résumé d'auteur

Characterising and modelling groundwater discharge in anagricultural wetland on the French Atlantic coast

Interaction between a wetland and its surrounding aquifer was studied in the Rochefort agricultural marsh (150 km²). Groundwater discharge in the marsh was measured with a network of nested piezometers. Hydrological modelling of the wetland showed that a water volume of 770,000 m³ yr^–1 is discharging into the marsh, but that this water flux essentially takes place along the lateral borders of the wetland. However, this natural discharge volume represents only 20% of the artificial freshwater injected each year into the wetland to maintain the water level close to the soil surface. Understanding and quantifying the groundwater component in wetland hydrology is crucial for wetland management and conservation.</b></p> <p style='line-height: 20px;'><b>Keywords: </b>wetland, hydrology, groundwater, modelling, mars

West African equatorial ionospheric parameters climatology based on Ouagadougou ionosonde station data from June 1966 to February 1998

This study is the first which gives the climatology of West African equatorial ionosphere by using Ouagadougou station through three solar cycles. It has permitted to show the complete morphology of ionosphere parameters by analyzing yearly variation, solar cycle and geomagnetic activity, seasonal evolution and diurnal development. This work shows that almost all ionospheric parameters have 11-year solar cycle evolution. Seasonal variation shows that only &lt;I&gt;fo&lt;/I&gt;F2 exhibits annual, winter and semiannual anomaly. &lt;I&gt;fo&lt;/I&gt;F2 seasonal variation has permitted us to identify and characterize solar events effects on F2 layer in this area. In fact (1) during quiet geomagnetic condition &lt;I&gt;fo&lt;/I&gt;F2 presents winter and semiannual anomalies asymmetric peaks in March/April and October. (2) The absence of winter anomaly and the presence of equinoctial peaks are the most visible effects of fluctuating activity in &lt;I&gt;fo&lt;/I&gt;F2 seasonal time profiles. (3) Solar wind shock activity does not modify the profile of &lt;I&gt;fo&lt;/I&gt;F2 but increases ionization. (4) The absence of asymmetry peaks, the location of the peaks in March and October and the increase of ionization characterize recurrent storm activity. F1 layers shows increasing trend from cycle 20 to cycle 21. Moreover, E layer parameters seasonal variations exhibit complex structure. It seems impossible to detect fluctuating activity effect in E layer parameters seasonal variations but shock activity and wind stream activity act to decrease E layer ionization. It can be seen from Es layer parameters seasonal variations that wind stream activity effect is fairly independent of solar cycle. E and Es layers critical frequencies and virtual heights diurnal variations let us see the effects of the greenhouse gases in these layers

Efficiency of the lausanne clinical pathway for proximal femoral fractures.

Purpose/Introduction: The number of hip fractures is rising, due to increases in life expectancy. In such cases, patients are at risk from post-operative complications and subsequently the average length of hospitalization may be extended. In 2011, we established a clinical pathway (CP), a specific model of care for patient-care management, to improve the clinical and economic outcomes of proximal femoral fracture management in elderly patients. The goal was to evaluate the CP using clinical, process, and financial indicators. METHODS: We included all surgical patients aged 65 and over, admitted to the emergency department with a fracture of the proximal femur following a fall. Assessment parameters included three performance indicators: clinical, process, and financial. The clinical indicators were the presence or absence of acute delirium on the third post-operative day, diagnosis of nosocomial pneumonia, and the number of patients fulfilling at least 75% of their nutritional requirements at the end of the hospitalization period. The process indicator was the time interval between arrival at the emergency department and surgery. The financial indicator was based on the number of days spent in hospital. RESULTS: From 2011 to 2013, 669 patients were included in the CP. We observed that the average length of stay in hospital decreased as soon as the CP was implemented and stabilized afterwards. The goal of 90% of patients undergoing surgery within 48 h of arrival in the emergency department was surpassed in 2013 (93.1%). Furthermore, we observed an improvement in the clinical indicators. CONCLUSION: The application of a CP allowed an improvement in the qualitative and quantitative efficiency of proximal femoral fracture management in elderly patients, in terms of clinical, process, and financial factors

Autonomy as a Central Category in the Concept of Health Promotion

Objectives: To describe the central concepts of health promotion in primary care in Brazil, through a review of case studies

Large area Al₂O₃–Au raspberry-like nanoclusters from iterative block-copolymer self-assembly

In the field of functional nanomaterials, core–satellite nanoclusters have recently elicited great interest due to their unique optoelectronic properties. However, core–satellite synthetic routes to date are hampered by delicate and multistep reaction conditions and no practical method has been reported for the ordering of these structures onto a surface monolayer. Herein we show a reproducible and simplified thin film process to fabricate bimetallic raspberry nanoclusters using block copolymer (BCP) lithography. The fabricated inorganic raspberry nanoclusters consisted of a ∼36 nm alumina core decorated with ∼15 nm Au satellites after infusing multilayer BCP nanopatterns. A series of cylindrical BCPs with different molecular weights allowed us to dial in specific nanodot periodicities (from 30 to 80 nm). Highly ordered BCP nanopatterns were then selectively infiltrated with alumina and Au species to develop multi-level bimetallic raspberry features. Microscopy and X-ray reflectivity analysis were used at each fabrication step to gain further mechanistic insights and understand the infiltration process. Furthermore, grazing-incidence small-angle X-ray scattering studies of infiltrated films confirmed the excellent order and vertical orientation over wafer scale areas of Al2O3/Au raspberry nanoclusters. We believe our work demonstrates a robust strategy towards designing hybrid nanoclusters since BCP blocks can be infiltrated with various low cost salt-based precursors. The highly controlled nanocluster strategy disclosed here could have wide ranging uses, in particular for metasurface and optical based sensor applications

Does ohmic heating influence the flow field in thin-layer electrodeposition?

In thin-layer electrodeposition the dissipated electrical energy leads to a substantial heating of the ion solution. We measured the resulting temperature field by means of an infrared camera. The properties of the temperature field correspond closely with the development of the concentration field. In particular we find, that the thermal gradients at the electrodes act like a weak additional driving force to the convection rolls driven by concentration gradients.Comment: minor changes: correct estimation of concentration at the anode, added Journal-re

Investigation of the prevalence of antibodies against neurotropic polyomaviruses BK, JC and SV40 in sera from patients affected by multiple sclerosis.

Viral agents seem to be linked to multiple sclerosis (MS). This association is based on evidence of (1) early exposure to viruses and MS onset; (2) increased prevalence of MS disease in specific geographic regions; (3) likelihood of developing MS being more prevalent in high-risk areas; (4) altered immune responses to different viruses. In this study, sera from patients affected by MS and controls, represented by sera from patients with other neurologic diseases, both inflammatory and non-inflammatory, and from healthy donors, were investigated for the presence of antibodies against neurotropic polyomaviruses BKV, JCV and SV40 in their sera. Our study has indicated that the prevalence of BKV antibodies in sera from MS patients is higher than that detected in normal individuals, while levels of antibodies against BKV and JCV are lower in MS patients compared to those of normal subjects