Dissolved and colloidal phosphorus fluxes in forest ecosystems—an almost blind spot in ecosystem research

Understanding and quantification of phosphorus (P) fluxes are key requirements for predictions of future forest ecosystems changes as well as for transferring lessons learned from natural ecosystems to croplands and plantations. This review summarizes and evaluates the recent knowledge on mechanisms, magnitude, and relevance by which dissolved and colloidal inorganic and organic P forms can be translocated within or exported from forest ecosystems. Attention is paid to hydrological pathways of P losses at the soil profile and landscape scales, and the subsequent influence of P on aquatic ecosystems. New (unpublished) data from the German Priority Program 1685 “Ecosystem Nutrition: Forest Strategies for limited Phosphorus Resources” were added to provide up‐to‐date flux‐based information. Nitrogen (N) additions increase the release of water‐transportable P forms. Most P found in percolates and pore waters belongs to the so‐called dissolved organic P (DOP) fractions, rich in orthophosphate‐monoesters and also containing some orthophosphate‐diesters. Total solution P concentrations range from ca. 1 to 400 µg P L^?1, with large variations among forest stands. Recent sophisticated analyses revealed that large portions of the DOP in forest stream water can comprise natural nanoparticles and fine colloids which under extreme conditions may account for 40–100% of the P losses. Their translocation within preferential flow passes may be rapid, mediated by storm events. The potential total P loss through leaching into subsoils and with streams was found to be less than 50 mg P m^?2 a^?1, suggesting effects on ecosystems at centennial to millennium scale. All current data are based on selected snapshots only. Quantitative measurements of P fluxes in temperate forest systems are nearly absent in the literature, probably due to main research focus on the C and N cycles. Therefore, we lack complete ecosystem‐based assessments of dissolved and colloidal P fluxes within and from temperate forest systems.     

Use of paramunization in raising pigs

The fundamentals of paramunization are briefly discussed to provide better understanding of paramunization of pigs. Veterinary practice and experimental studies demonstrate the usefulness, efficacy and harmlessness of paramunization of pigs. Mortality, morbidity as well as weight gain in piglets are used to evaluate the effect of the inducers PIND-AVI and/or PIND-ORF on piglets which have been treated shortly after birth. The therapeutic effect of paramunization has been studied in herds with enzootic pneumonia. Paramunization is especially suitable in stimulating the immune system, in treating immune deficiencies, in the prophylaxis of the stress syndrome (e.g. induced by transport, weaning, changing stalls, etc.) and in treating pluricausal, multifactorial infectious diseases such as enzootic pneumonia, rhinitis atrophicans, "crowding" disease. Paramunization of pigs is discussed, using PIND-ORF as an example of a biological inducer. Paramunization as a biological method to stimulate immunity provides a new concept of prophylaxis and therapy opposed to the uncontrolled use of chemicals in pig production.     

Trawl fishing impacts on the status of seabed fauna in diverse regions of the globe

Bottom trawl fishing is a controversial activity. It yields about a quarter of the world's wild seafood, but also has impacts on the marine environment. Recent advances have quantified and improved understanding of large‐scale impacts of trawling on the seabed. However, such information needs to be coupled with distributions of benthic invertebrates (benthos) to assess whether these populations are being sustained under current trawling regimes. This study collated data from 13 diverse regions of the globe spanning four continents. Within each region, we combined trawl intensity distributions and predicted abundance distributions of benthos groups with impact and recovery parameters for taxonomic classes in a risk assessment model to estimate benthos status. The exposure of 220 predicted benthos‐group distributions to trawling intensity (as swept area ratio) ranged between 0% and 210% (mean = 37%) of abundance. However, benthos status, an indicator of the depleted abundance under chronic trawling pressure as a proportion of untrawled state, ranged between 0.86 and 1 (mean = 0.99), with 78% of benthos groups > 0.95. Mean benthos status was lowest in regions of Europe and Africa, and for taxonomic classes Bivalvia and Gastropoda. Our results demonstrate that while spatial overlap studies can help infer general patterns of potential risk, actual risks cannot be evaluated without using an assessment model that incorporates trawl impact and recovery metrics. These quantitative outputs are essential for sustainability assessments, and together with reference points and thresholds, can help managers ensure use of the marine environment is sustainable under the ecosystem approach to management.     

Parvovirus infections in dogs and cats: problems of immunization

The general problems of immunization against parvoviroses are only understandable when knowing the basic principles of epidemiology, pathogenesis and immunology of those virus infections. The main difficulties with regard to vaccinations are 1. efficacy of homologous respectively heterologous vaccines, 2. indications for live resp. inactivated vaccines, 3. combination with other vaccines, 4. bridging of the "immunological gap" (refractory phase) of puppies, 5. mode of application and timing of vaccinations (schedule of vaccinations), 6. failure in vaccinated animals, 7. complications originating from vaccinations, 8. passive immunization.     

Macrophakia in three cats

This report describes three cases of bilateral macrophakia in 3-, 5-, and 9-year-old cats, respectively. All cats were presented because of visual deficits. Ophthalmic examination revealed macrophakia (the vitreous was replaced by the lens) and retinal changes (tapetal hyper-reflectivity, attenuation of retinal vessels, and retinal folds) in all cats. In addition, bilateral subconjunctival orbital fat prolapse in one cat and microphthalmos in another cat were present. To confirm the ophthalmologic diagnosis of macrophakia, gross pathology examination in one cat and ultrasound examination in another cat were performed.     

农产品质量安全突发事件应急检测

随着人们生活水平的提升,农产品质量安全成为当前人们关注的热点问题。从现实社会中来看,很多地区都存在着农产品质量安全问题,如突发事件的产生往往让人猝不及防,也容易对人们的身体健康状况带来不利影响。文章就针对我国农产品质量安全突发事件应急检测等进行研究,分析其突发事件产生的原因和事件特点,并提出相应的解决对策,希望能为农产品质量的提升提供借鉴。     

Innovation in the periphery: Compensation and exploitation strategies

Recent research has challenged the urban bias in economic geography and innovation studies, showing that highly innovative and competitive firms are also located in peripheral regions. So far, however, analyses has focused on how firms innovate despite their unfavourable location and little has been said about the innovation benefits of peripheral areas. Hence, this article identifies different compensation and exploitation strategies adopted by firms in order to overcome regional innovation constraints and to reap innovation benefits found in the periphery. Drawing on 20 in‐depth qualitative interviews with innovative firms situated in the Austrian periphery, our analysis reveals that innovation in peripheral regions is the outcome of a combination of compensation and exploitation practices. The uptake and composition of these strategies depend on the firm and regional characteristics, with firm size being the most influential factor.     

Multiple forms of xylose reductase in Candida intermedia: comparison of their functional properties using quantitative structure-activity relationships, steady-state kinetic analysis, and pH studies

The xylose-fermenting yeast Candida intermedia produces two isoforms of xylose reductase: one is NADPH-dependent (monospecific xylose reductase; msXR), and another is shown here to prefer NADH approximately 4-fold over NADPH (dual specific xylose reductase; dsXR). To compare the functional properties of the isozymes, a steady-state kinetic analysis for the reaction d-xylose + NAD(P)H + H(+) <--> xylitol + NAD(P)(+) was carried out and specificity constants (k(cat)/K(aldehyde)) were measured for the reduction of a series of aldehydes differing in side-chain size as well as hydrogen-bonding capabilities with the substrate binding pocket of the enzyme. dsXR binds NAD(P)(+) (K(iNAD+) = 70 microM; K(iNADP+) = 55 microM) weakly and NADH (K(i) = 8 microM) about as tightly as NADPH (K(i) = 14 microM). msXR shows uniform binding of NADPH and NADP(+) (K(iNADP+) approximately K(iNADPH) = 20 microM). A quantitative structure-activity relationship analysis was carried out by correlating logarithmic k(cat)/K(aldehyde) values for dsXR with corresponding logarithmic k(cat)/K(aldehyde) values for msXR. This correlation is linear with a slope of approximately 1 (r (2) = 0.912), indicating that no isozyme-related pattern of substrate specificity prevails and aldehyde-binding modes are identical in both XR forms. Binary complexes of dsXR-NADH and msXR-NADPH show the same macroscopic pK of approximately 9.0-9.5, above which the activity is lost in both enzymes. A lower pK of 7.4 is seen for dsXR-NADPH. Specificity for NADH and greater binding affinity for NAD(P)H than NAD(P)(+) are thus the main features of enzymic function that distinguish dsXR from msXR.     

How low can you go? Physical production mechanism of elephant infrasonic vocalizations

Elephants can communicate using sounds below the range of human hearing ("infrasounds" below 20 hertz). It is commonly speculated that these vocalizations are produced in the larynx, either by neurally controlled muscle twitching (as in cat purring) or by flow-induced self-sustained vibrations of the vocal folds (as in human speech and song). We used direct high-speed video observations of an excised elephant larynx to demonstrate flow-induced self-sustained vocal fold vibration in the absence of any neural signals, thus excluding the need for any "purring" mechanism. The observed physical principles of voice production apply to a wide variety of mammals, extending across a remarkably large range of fundamental frequencies and body sizes, spanning more than five orders of magnitude.