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11.
Philip W. Atkinson Graham E. Austin Mark M. Rehfisch Helen Baker Peter Cranswick Mel Kershaw James Robinson Rowena H.W. Langston David A. Stroud Chris Van Turnhout Ilya M.D. Maclean 《Biological conservation》2006,130(4):549-559
To manage and conserve wildlife populations effectively it is necessary to use methods that identify the often non-linear trends in populations, have an inbuilt assessment of trend quality and can analyse count data from a range of spatial scales. We present a method of trend analysis using generalised additive models. These produce smoothed indices of abundance that can be used to assess population change from one or more sites or time periods, with any number of estimates of abundance per index period. We apply this method to count data collected under the Wetland Bird Survey, a national scheme that monitors waterbirds in the United Kingdom. To highlight declining populations, ‘alerts’ were raised if the population decline was equal to or greater than 50%. Significance was determined using bootstrapped confidence intervals for analyses that included many sites, or a novel Monte-Carlo method for single site analyses. The impact of missing data, species count variability and the number of months used to calculate the population change was greater at individual sites than for national datasets, which were relatively insensitive to changes in the above parameters. For single sites it is essential that three or more counts be made per index period if reliable estimates of population change are required. We propose that the method presented could be applied to a wide range of national or other monitoring schemes for a variety of taxa. 相似文献
12.
Setting wildlife conservation priorities and determining how to meet them is challenging, particularly when policy decisions made at large scales need to be informed by a diversity of local conditions. The persistence of species that range widely demands that they coexist with people both within and outside formally protected areas. It is often politically and financially infeasible for one central body, such as a government wildlife agency, to monitor an entire population. Therefore, conservation planners are increasingly turning to local knowledge to inform conservation decisions. Here, we show the scientific and conservation benefits of recruiting and training local community members to collect data on an endangered species, the Grevy’s zebra (Equus grevyi). We recruited 18 scouts from six community-held ranches in Samburu District, Kenya. The scouts record the location, group structure and habitat of all Grevy’s zebra herds seen in walking surveys. Kernel analyses of scout herd observations indicate areas heavily used by Grevy’s zebra, and the subset of these areas favored by females with young foals. The important areas identified by the scouts closely match those inferred from analyses of GPS radiocollar data. Further, scout data reveals extensive spatial and temporal overlap between livestock and Grevy’s zebra. This overlap suggests the potential for competition between Grevy’s zebra and domestic animals. We argue that scout programs such as ours can generate valuable insights for conservation planning. In addition, such programs have the potential to improve local attitudes toward wildlife conservation. 相似文献
13.
Roopchand DE Kuhn P Poulev A Oren A Lila MA Fridlender B Raskin I 《Journal of agricultural and food chemistry》2012,60(36):8860-8865
Defatted soybean flour (DSF) can efficiently sorb, concentrate, and stabilize polyphenols, but not sugars, from Concord grape juice, to yield grape polyphenol-enriched DSF. Sorption of grape polyphenols to DSF particles was dependent on the ratio of DSF and grape juice concentrate used, but not time of mixing or pH. Depending on ratios of starting materials, 1 g of grape polyphenol-enriched DSF contained 1.6-10.4 mg of anthocyanins, 7.5-93.1 mg of proanthocyanidins, and 20.5-144.5 mg of total polyphenols. LC-MS analysis of grape juice samples before and after addition and removal of DSF and eluate from grape polyphenol-enriched DSF confirmed that a broad range of grape compounds were sorbed to the DSF matrix. Finally, grape polyphenol-enriched DSF was able to significantly lower blood glucose levels in hyperglycemic C57BL/6J mice. The data indicate that grape polyphenol-enriched DSF can provide a high-protein, low-sugar ingredient for delivery of concentrated grape polyphenolics. 相似文献
14.
Ion channels are tightly involved in various aspects of cell physiology, including cell signaling, proliferation, motility, endo- and exo-cytosis. They may be involved in toxin production and release by marine dinoflagellates, as well as harmful algal bloom proliferation. So far, the patch-clamp technique, which is the most powerful method to study the activity of ion channels, has not been applied to dinoflagellate cells, due to their complex cellulose-containing cell coverings. In this paper, we describe a new approach to overcome this problem, based on the preparation of spheroplasts from armored bloom-forming dinoflagellate Prorocentrum minimum. We treated the cells of P. minimum with a cellulose synthesis inhibitor, 2,6-dichlorobenzonitrile (DCB), and found out that it could also induce ecdysis and arrest cell shape maintenance in these microalgae. Treatment with 100–250 µM DCB led to an acceptable 10% yield of P. minimum spheroplasts and was independent of the incubation time in the range of 1–5 days. We show that such spheroplasts are suitable for patch-clamping in the cell-attached mode and can form 1–10 GOhm patch contact with a glass micropipette, allowing recording of ion channel activity. The first single-channel recordings of dinoflagellate ion channels are presented. 相似文献
15.
Throughout the world, but particularly in tropical regions habitat loss and disturbance are considered detrimental to biodiversity. We examine the effects of disturbance by harvesting, burning and habitat fragmentation on six bird species associated with papyrus (Cyperus papyrus) swamps. The presence or absence of these species was verified in 93 wetlands in southern Uganda between June and August 2003. Disturbance was estimated directly by observation and indirectly from examining vegetation structure. Habitat fragmentation was quantified by delineating swamps on Landsat ETM images and applying ‘Fragstats’ to calculate relevant patch metrics. The occurrence of all six species was affected positively by increased swamp size, but birds were more likely to occur in small swamps at high altitude. The shape and proximity of swamps to neighbouring wetlands had little effect on occurrence. As altitude, habitat fragmentation and disturbance were correlated, determining avian responses to disturbance was problematic. However, the occurrence of all species was affected by disturbance, often showing unimodal responses, if disturbance was not considered in conjunction with habitat fragmentation. When the effects of habitat fragmentation and disturbance were analysed together, only the occurrences of papyrus yellow warbler and white-winged warbler were affected (positively) by disturbance. Results suggest that papyrus-dwelling passerines, except papyrus gonolek, are tolerant of low intensities of disturbance, a novel finding in the tropics. We recommend that policy-makers do not prohibit harvesting, thus generating good will and encouraging rural householders to comply with additional conservation policy. 相似文献
16.
An aqueous ethanol extract of Pyrola rotundifolia L. induced AMP-activated protein kinase (AMPK) phosphorylation in C2C12 myotubes. The bioassay-guided fractionation of the extract led to the isolation a 2-methyl-7-hydroxymethyl-1,4-naphthoquinone, or a 7′-hydroxy-chimaphilin, which showed concentration-dependent AMPK phosphorylation activity at 2.5–20 μg/ml. At a concentration of 10 μg/ml (50 μM), an approximately four-fold increase in the AMPKα(Thr172) phosphorylation level was observed. The stimulatory effect of naphthoquinone on AMPK activity was comparable to that of known compounds found in natural sources that activate the AMPK signaling pathway. 相似文献
17.
Fushman I Englund D Faraon A Stoltz N Petroff P Vuckovic J 《Science (New York, N.Y.)》2008,320(5877):769-772
Optical nonlinearities enable photon-photon interaction and lie at the heart of several proposals for quantum information processing, quantum nondemolition measurements of photons, and optical signal processing. To date, the largest nonlinearities have been realized with single atoms and atomic ensembles. We show that a single quantum dot coupled to a photonic crystal nanocavity can facilitate controlled phase and amplitude modulation between two modes of light at the single-photon level. At larger control powers, we observed phase shifts up to pi/4 and amplitude modulation up to 50%. This was accomplished by varying the photon number in the control beam at a wavelength that was the same as that of the signal, or at a wavelength that was detuned by several quantum dot linewidths from the signal. Our results present a step toward quantum logic devices and quantum nondemolition measurements on a chip. 相似文献
18.
A Novel Zero Discharge Intensive Seawater Recirculating System for the Culture of Marine Fish 总被引：2，自引：0，他引：2
Ilya Gelfand Yoram Barak Ziv Even-Chen Eddie Cytryn Jaap Van Rijn Michael D. Krom Amir Neori 《Journal of the World Aquaculture Society》2003,34(3):344-358
Results are presented of a zero‐discharge marine recirculating system used for the culture of gilthead seabream Sparus aurata. Operation of the system without any discharge of water and sludge was enabled by recirculation of effluent water through two separate treatment loops, an aerobic trickling filter and a predominantly anoxic sedimentation basin, followed by a fluidized bed reactor. The fish basin was stocked for the first 6 mo with red tilapia Oreochromis niloticus × O. aureus at an initial density of 16 kg/m3. During this period salinity was raised from 0 to 20 parts per thousand. Then, gilthead seabream, stocked at an initial density of 21 kg/m3, replaced tilapia at day 167 and were cultured for an additional 225 d. Non steady‐state inorganic nitrogen transformations occurred as a result of these salinity changes. After day 210, the system operated at all times with those water quality parameters considered critical for successful operation of mariculture systems, within acceptable limits. Thus ammonia, nitrite, and nitrate concentrations did not exceed 1.0‐mg total ammonia‐N/ L, 0.5‐mg NO2:‐N/L and 50‐mg NO3‐N/L, respectively. Sulfide levels in the fish basin were below detection limits and oxygen > 6 mg/L after the oxygen generator was added at day 315. Ammonia, produced in the fish basin and to a lesser extent in the sedimentation basin, was converted to nitrate in the aerobic trickling filter. Nitrate removal took place in the sedimentation basin and to a lesser extent in the fluidized bed reactor. Sludge, remaining in the sedimentation basin at the end of the experimental period, accounted for 9.2% of the total feed dry matter addition to the system. The system was disease‐free for the entire year and fish at harvest were of good quality. Water consumption for production of 1 kg of tilapia was 93 L and 214 L for production of 1 kg of gilthead seabream. Additional growth performance data of gilthead seabream cultured in a similar but larger system are presented. During 164 d of operation of the latter system, maximum stocking densities reached 50 kgl M3 and fish biomass production was 27.7 kg/m3. Relatively poor fish survival and growth resulted from occasional technical failures of this pilot system. 相似文献
19.
Gad?G.?Yousef Mary?H.?Grace Jorge?L.?Guerrero?Medina Scott?Neff Ivette?Guzman Allan?F.?Brown Ilya?Raskin Mary?Ann?LilaEmail author 《Plant foods for human nutrition (Dordrecht, Netherlands)》2014,69(4):317-324
Co-delivery of edible proteins with health-protective fruit (muscadine grape) and vegetable (kale) phytoactive compounds was accomplished in a biofortified ingredient for use in convenient, portable food formulations. Polyphenolics were concentrated (10–42 mg/g range) in dry muscadine-protein matrices. Kale-fortified protein matrices also captured polyphenolics (8 mg/g), carotenoids (69 μg/g) and glucosinolates (7 μmol/g). Neither total phenolics nor glucosinolates were significantly diminished even after long term (6 months) storage at 4, 20, or 37 °C, whereas carotenoids degraded over time, particularly at higher temperatures. Dry biofortified phytoactive-protein ingredients allowed delivery of immunoprotective compounds from fruits and vegetables in a stable, lightweight matrix. 相似文献
20.
Andi Flory Lisa McLennan Betsy Peet Marissa Kroll Deirdre Stuart Devon Brown Kathy Stuebner Brenda Phillips Brenda L. Coomber J. Paul Woods Mairin Miller Chelsea D. Tripp Amber Wolf-Ringwall Kristina M. Kruglyak Angela L. McCleary-Wheeler Ashley Phelps-Dunn Lilian K. Wong Chelsea D. Warren Gina Brandstetter Michelle C. Rosentel Lauren R. DiMarzio Allison L. O'Kell Todd A. Cohen Daniel S. Grosu Jason Chibuk Dana W. Y. Tsui Ilya Chorny Jill M. Rafalko 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2023,37(1):258-267