Soil fertility and GIS raster models for tropical agroforestry planning in economically depressed and contaminated Caribbean areas (coffee and kidney bean plantations)     

Stervins Alexis  Luis G. García-Montero  Ana J. Hernández  Antonio García-Abril  Jesús Pastor 《Agroforestry Systems》2010,79(3):381-391

In the jaragua-bahoruco-enriquillo biosphere reserve, located on the southern border between the Dominican Republic and Haiti, there are depressed rural areas with soils with high content in Cadmium and other heavy metals which originate naturally in the geological substrate. Data from 80 soils and an inventory of 76 plantations (coffee and kidney bean were used) to design a GIS (geographic information systems) tool which integrated statistical multivariate methods, soil parameters including heavy metal content into models of land planning, agricultural development, forests and protection of the health of the area’s inhabitants and the natural environment. This GIS tool is based on raster models of an open source, which use combination and reclassification operations based on the maps, geostatistical methods (Kriging), statistical analyses external to the GIS, and cartography of limiting and excluding particular factors for crops (including heavy metal soil content). The GIS tool developed discriminates extreme situations in sustainable agroforestry planning in contaminated rural areas of the Caribbean, Central America and other tropical regions.  相似文献   

Epicormics in 13-year-old Quercus petraea: small effect of provenance and large influence of branches and growth unit limits     

Francis Colin  Alexis Ducousso  Florence Fontaine 《Annals of Forest Science》2010,67(3):312-312

? The provenance effect on epicormics is poorly documented and restricted to epicormic shoots. Our objective was to characterize the relationship between epicormics and provenance on 13-year-old Quercus petraea trees, taking into account their growth traits.

? On the growth units (GU) studied, epicormics were essentially isolated buds (95%) and they were mainly located at branch bases, secondarily on GU limits and marginally on lateral position. Provenance effect was very small on the number of epicormics and slightly larger on the number of branches and GU limits. On the contrary, the growth situation-independently from provenance-proved to have a larger effect on the 2 latter growth traits.

? Altogether, these results clearly show the predominant effect of morphological traits and thus of ontogeny. This opens important research perspectives: how growth conditions and genetics (at progeny and individual levels) influence height growth, setting and fate of axillary buds on the one hand and fate of epicormic buds inserted directly on the stem, or at branch bases on the other hand.

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Structure-Activity Relationships of the Bioactive Thiazinoquinone Marine Natural Products Thiaplidiaquinones A and B     

Jacquie L. Harper  Iman M. Khalil  Lisa Shaw  Marie-Lise Bourguet-Kondracki  Jo?lle Dubois  Alexis Valentin  David Barker  Brent R. Copp 《Marine drugs》2015,13(8):5102-5110

In an effort to more accurately define the mechanism of cell death and to establish structure-activity relationship requirements for the marine meroterpenoid alkaloids thiaplidiaquinones A and B, we have evaluated not only the natural products but also dioxothiazine regioisomers and two precursor quinones in a range of bioassays. While the natural products were found to be weak inducers of ROS in Jurkat cells, the dioxothiazine regioisomer of thiaplidiaquinone A and a synthetic precursor to thiaplidiaquinone B were found to be moderately potent inducers. Intriguingly, and in contrast to previous reports, the mechanism of Jurkat cell death (necrosis vs. apoptosis) was found to be dependent upon the positioning of one of the geranyl sidechains in the compounds with thiaplidiaquinone A and its dioxothiazine regioisomer causing death dominantly by necrosis, while thiaplidiaquinone B and its dioxothiazine isomer caused cell death via apoptosis. The dioxothiazine regioisomer of thiaplidiaquinone A exhibited more potent in vitro antiproliferative activity against human tumor cells, with NCI sub-panel selectivity towards melanoma cell lines. The non-natural dioxothiazine regioisomers were also more active in antiplasmodial and anti-farnesyltransferase assays than their natural product counterparts. The results highlight the important role that natural product total synthesis can play in not only helping understand the structural basis of biological activity of natural products, but also the discovery of new bioactive scaffolds.  相似文献   

Biological characteristics of the hydrological landscapes in the Bay of Biscay in spring 2009          下载免费PDF全文

Ainhoa Lezama‐Ochoa  Daniel Grados  Anne Lebourges‐Dhaussy  Xabier Irigoien  Alexis Chaigneau  Arnaud Bertrand 《Fisheries Oceanography》2015,24(1):26-41

In the present study we investigated the biogeography of macrozooplankton and fish biomass in the Bay of Biscay. In this region, we defined six different landscapes based on the hydrogeographical characteristics observed in spring 2009. We then related landscape's characteristics and environmental parameters such as light attenuation depth and chlorophyll‐a with macrozooplankton and fish acoustic biomass. Hydrodynamic structures together with coastal influences (river discharges, predation pressure and depth preference) and vertical thermohaline structure/mixing (feeding modes and ability to stay in preferred layers) appeared as the main factors determining the biological distribution. Besides, variance partitioning was used to assess the respective roles played by the hydrological environment, the geographical space and the biological environment alone, and their interactions. Results revealed that: (i) macrozooplankton and fish have a preference for different hydrogeographical landscapes; (ii) the association between hydrological conditions and geographical features, i.e. the spatial structure of the hydrological environment, plays a key role in the distribution of macrozooplankton; and (iii) prey–predator relationships have to be taken into account to provide a comprehensive characterization of habitat suitability.  相似文献   

Effects of DL-methionine-supplemented dietary soy protein concentrate on growth performance and intestinal enzyme activity of gilthead sea bream (Sparus aurata L.)     

Fotini Kokou  George Rigos  Maroudio Kentouri  Maria Alexis 《Aquaculture International》2016,24(1):257-271

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Executive summary of the CATalyst Council's cat-friendly practice makeover study     

Tennyson B  Brunt J  Nahama A 《Journal of the American Veterinary Medical Association》2012,241(1):58-62

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Responses of small rodents to habitat restoration and management for the imperiled Florida Scrub-Jay     

Alexis A. Suazo  John E. Fauth  James D. Roth  Christopher L. Parkinson  I. Jack Stout   《Biological conservation》2009,142(10):2322-2328

Debate about the relative merits of single-species management versus more comprehensive approaches has intensified in recent years. In east-central Florida, USA, land managers use prescribed burns and mechanical cutting to manage and restore scrub habitat to benefit the imperiled Florida Scrub-Jay (Aphelocoma coerulescens). However, these land-management techniques may affect non-target taxa, especially the threatened southeastern beach mouse (Peromyscus polionotus niveiventris). We evaluated the collateral effects of single-species land management by trapping P. p. niveiventris and other small rodents in eighteen land-management compartments at Cape Canaveral Air Force Station, Florida during 2004–2005. Compartments were managed using either prescribed burns (N = 5), mechanical cutting (N = 6), checkerboarding (cut and uncut lanes alternating and overlapping, followed by a prescribed burn, N = 4) or left unburned and uncut for >50 year (N = 3). P. p. niveiventris was significantly more abundant in compartments managed with prescribed burns (mean ± SE: 4.2 ± 0.7 individuals/transect) than those managed with cutting alone (1.0 ± 0.3) or not managed for >50 y (0.2 ± 0.1 individuals/transect). In contrast, the cotton mouse (Peromyscus gossypinus) tended to be more abundant in compartments managed with mechanical cutting alone (2.6 ± 0.4 individuals/transect) compared to the other three management strategies (prescribed burns; 1.5 ± 0.4; checkerboarding, 1.1 ± 0.3; not managed, 1.6 ± 0.4 individuals/transect) but these differences were not statistically significant. Abundances of P. p. niveiventris and Florida Scrub-Jay breeding groups were positively correlated (r = 0.655), suggesting that both listed species benefit from similar management techniques. Thus, the mosaic of burned and cut patches used to improve habitat for the Florida Scrub-Jay also benefits an endemic, non-target species. Single-species management may benefit multiple species when restoration improves their shared habitat, which in this case is an endangered, fire-dependent ecosystem: Florida scrub.  相似文献   

Diet and pregnancy status in Australian women     

Hure A  Young A  Smith R  Collins C 《Public health nutrition》2009,12(6):853-861

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Reversible anesthesia in wild marine otters (Lontra felina) using ketamine and medetomidine.     

Claudio Soto-Azat  Francisca Boher  Gabriela Flores  Eileen Mora  Alexis Santiba?ez  Gonzalo Medina-Vogel 《Journal of zoo and wildlife medicine》2006,37(4):535-538

Nine marine otters (Lontra felina) were anesthetized 15 times with a combination of ketamine (5.3 +/- 0.9 [range: 4.5-8.0] mg/kg) and medetomidine (53 - 9 [range: 45-80] microg/kg) i.m. by hand syringe for the placement of radiotransmitters. Times to initial effect and induction period ranged from 1.1 to 5.0 min and 1.8 to 5.4 min, respectively. Minor complications did occur, including mild hypothermia in six otters and severe hypoxemia in one otter. After 34 and 63 min, anesthesia was antagonized with atipamezole (226 +/- 29 [range: 179-265] microg/kg) and all otters recovered within 3.3-26.8 min.  相似文献   

The stability of different silvicultural systems: a wind-tunnel investigation   总被引：2，自引：0，他引：2  

Gardiner  Barry; Marshall  Bryan; Achim  Alexis; Belcher  Rex; Wood  Colin 《Forestry》2005,78(5):471-484

We report on a wind-tunnel study with 1 : 75 scale model treesdesigned to examine the influence of canopy structure on theformation of turbulent gusts above forests. This was to testthe hypothesis that more irregular canopy structures produceless intense gusts because the change in wind speed with heightat canopy top is less severe. Measurements were made of windspeeds and turbulence within and above the model forests andof the wind loading on model trees in four different silviculturalsystems. The systems tested were even-aged, single-tree selection,shelterwood/group selection and strip felling. The measurementsshowed that the profiles of different mean wind and turbulencecharacteristics above the forests are remarkably similar whenvertical heights are normalized by the height of the tallesttree but differences do exist within the canopy. The wind loadingmeasurements indicated no difference between the systems interms of stability except possibly for the shelterwood/groupselection. In the shelterwood/group selection system the presenceof smaller sub-canopy trees appears to reduce the loading onthe main canopy trees either by providing support and increasingdamping or by absorption of energy from the canopy-penetratinggusts.  相似文献