HOW DO WE DETERMINE PLANT QUALITY OF ORGANIC CROPS?

Plants are photoautotrophic organisms being able to synthesize all metabolites and macro-molecules on the basis of light, CO2, H2O and 14 inorganic elements taken up from the soil. As plants are confined to the environment in which they germinate, this means that the plant ionome, metabolome and proteome are heavily influenced by soil mineralogy, climate and not least agricultural management. Organic plant products within the European Union are produced according to a specific set of regulations, which e.g. implicate that organic plants are cultivated without pesticides and synthetically produced nitrogen (N) fertilizers. In addition, N fertilizers are often used in lower amounts relative to conventional agriculture. Over more than a decade it has been intensively studied whether these marked agronomical differences lead to systematic differences in the chemical composition of plant tissue and whether this has an impact on selected plant quality attributes. From a theoretical point of view the marked differences in fertilization strategies between organic and conventional agriculture will cause systematic differences in the chemical composition of plants. The differences are expected to be very large when comparing plants representing the extremes of organic and conventional agriculture. Thus, if synthetic fertilizers are used exclusively for conventional plant production and in high amounts relative to organic production based on animal manure, green manures, compost etc., the conventional plants are likely to differ from the organic ones. However, in most cases plants are not produced with such extreme fertilization strategies and differences are often masked by natural variation caused by e.g. geographical locations and growth season and thereby little difference in plant quality is usually observed. Despite the fact that systematic differences in chemical composition between organic and conventional plants are usually overridden by natural variation it was recently found that the type of N fertilizers is reflected in the isotope ratios of plants and that the isotopic fingerprints are unbiased by geographical locations and growth season. However, the fundamental differences in isotope ratios are supposedly irrelevant regarding plant quality, but have shown to be a strong signature for authentication of organic plants products. In this lecture we will further explain how the fertilization strategy can affect the underlying biochemical mechanisms controlling the chemical composition of plants and discuss how these are related to organic plant quality. Special attention will be given to N fertilizer forms and quantity, as fertilization generally appears to be the single-most parameter with the strongest impact on metabolism when comparing plants from organic and conventional agricultural systems

Is it really organic? Authenticity testing of organic plant products using elemental and isotopic fingerprinting

The commercial market for high-value plant products is steadily increasing. Consumers are willingly paying premium prices for plants that originate from specific geographical regions or are produced according to certain agricultural management practices. This has significantly enhanced the market shares of organically grown plant products but has simultaneously increased the risk of food adulteration and fraudulent activities. Consequently, sophisticated analytical principles are currently being developed to enable discrimination of organic and conventional plants and ensure compliance with the regulations of organic agriculture. Some of the most promising principles for organic authentication are based on atomic spectroscopy which encompasses several analytical techniques suitable for analysis of the elemental and isotopic composition of plants (1). Analytical discrimination of organic and conventional plant products relies on an expectation of systematic differences in agricultural management practices. Thus, it has been hypothesized that the prohibition of pesticides and synthetically produced fertilizers in organic agriculture is reflected in the chemical composition of plants. This hypothesis was recently tested in a Danish research project called OrgTrace, in which analytical methods for elemental and isotopic fingerprinting were developed and combined with multivariate statistics for authenticity testing of organic crops (2-4). The unique experimental design of OrgTrace included numerous plant species grown either organically or conventionally at several geographical locations differing in soil type, climate etc. Furthermore, year-to-year variation was assessed by inclusion of two growth years. Results from the OrgTrace project will be presented at the seminar. Recently, the international research project AuthenticFood was initiated. In AuthenticFood novel analytical procedures will be tested and combined to enable authentication of selected organic plant products before and after processing of these. The main research hypotheses and methodologies of AuthenticFood will be presented

Utilization of immobilized urease for waste water treatment

The feasibility of using immobilized urease for urea removal from waste water for space system applications is considered, specifically the elimination of the urea toxicity problem in a 30-day Orbiting Frog Otolith (OFO) flight experiment. Because urease catalyzes the hydrolysis of urea to ammonia and carbon dioxide, control of their concentrations within nontoxic limits was also determined. The results of this study led to the use of free urease in lieu of the immobilized urease for controlling urea concentrations. An ion exchange resin was used which reduced the NH3 level by 94% while reducing the sodium ion concentration only 10%

Fingerprint analysis of biological samples using ICP-MS and IR-MS

Atomic spectroscopy based analytical techniques can generate fingerprints encompassing the vast majority of elements found in the periodic table as well as ratios of their stable isotopes. These highly multivariate fingerprints have laid the foundation of many recent studies within environmental, geological, agricultural and food science. Inductively coupled plasma-optical emission spectroscopy (ICP-OES) and ICP-mass spectrometry (ICP-MS) still dominate multi-elemental analyses of biological samples while stable isotopes of the light mass elements H, C, N, O and S are measured by isotope ratio-mass spectrometry (IR-MS). However, it has recently been shown that rather unexplored analytical methods such as semi-quantitative ICP-MS and compound-specific isotope analysis (CSIA) can generate novel information suitable for evaluating the authenticity of plant based food products (1-3). Most plant based studies using atomic spectroscopy have focused on the essential nutrients: B, Mg, P, S, K, Ca, Mn, Fe, Ni, Cu, Zn, Mo and selected heavy metals such as Cd and Pb (4). However, plants contain traces of most of the periodic table, which can be measured by semi-quantitative ICP-MS (1-2). This represents a fast method for elemental fingerprinting in the mass range 7Li to 238U, but the accuracy suffers from the simplified calibration procedure that this technique is based on. The combination of semi-quantitative ICP-MS and multivariate statistics (chemometrics) efficiently minimize this problem and constitute a promising tool for authentication of plant products according to their geographical origin and production form (2). Stable isotope analysis complements elemental fingerprinting by targeting specific biological processes and their impact on the isotopic plant composition. This has recently proven valuable for authenticating organically grown plant products – especially when focusing on selected isotope pairs in plant derived compounds such as 18O/16O in NO3- using CSIA (3). Cases of novel atomic spectroscopy based food authentications will be presented at the conference

Patterns and determinants of inefficiency in state manufacturing

A study of whether states differ in terms of technical inefficiency in their manufacturing sectors.Regional economics ; Productivity ; Manufactures

Fifth annual conference on Alaskan placer mining

An abridged format of papers, presentations and addresses given during the 1983 conference held on March 30-31, 1983 compiled and edited by Bruce W. Campbell, Jim Madonna, and M. Susan Husted.Partial funding was provided by the Carl G. Parker Memorial Publishing Fund, University of Alaska, Fairbanks, and the Mining and Mineral Resources Research Institute, U.S. Department of the Interior, Bureau of Mines

Do States Free Ride in Antitrust Enforcement?

Recent research has documented a substantial role in antitrust enforcement by U.S. states. While many of the cases litigated involve small local firms, a non-trivial portion encompass multiplestate issues. Some previous literature has investigated whether states engage in free-riding behavior in environmental regulation, and whether governments free ride on private decisions in provision of public goods. In this paper, we analyze a sample of antitrust cases involving crossstate impacts (from the Multi-State Antitrust Database, provided by the National Association of Attorneys General) and explain the determinants of free-riding (which we define as participatingin a case, but not as a lead plaintiff). JEL classification:

Ustekinumab treatment and improvement of physical function and health‐related quality of life in patients with psoriatic arthritis

Objective: Examine ustekinumab effects on patient-reported outcomes (PROs) in PSUMMIT-1/PSUMMIT-2 patients with active psoriatic arthritis (PsA) who were methotrexate (MTX)-naïve, MTX-experienced, or anti-tumor necrosis factor (TNF)-experienced. Methods: Patients in the Phase 3, PSUMMIT 1 (n=615) and PSUMMIT 2 (n=312) studies randomly (1:1:1) received placebo, ustekinumab 45 mg, or ustekinumab 90 mg subcutaneous injections at wk0/wk4/wk16/wk28/wk40/wk52. PROs (Health Assessment Questionnaire-Disability Index [HAQ-DI]; Dermatology Life Quality index [DLQI]; 36-item short-form health survey physical and mental component summary [SF-36 PCS/MCS] scores; patient assessments of pain and disease activity; impact of disease on productivity) were assessed at wk0/wk24/wk52. In these post-hoc analyses, outcomes were compared between the ustekinumab and placebo groups for three mutually-exclusive antecedent-exposure populations from the combined studies: MTX/anti-TNF naïve (placebo, n=56; 45 mg, n=58; 90 mg, n=66), MTX-experienced, bio-naive (placebo, n=192; 45 mg, n=190; 90 mg, n=185), and anti-TNF experienced with or without MTX (placebo, n=62; 45 mg, n=60, 90 mg, n=58). Results: At wk24, mean improvements from baseline in HAQ-DI, DLQI, and SF-36 PCS scores were significantly greater in both ustekinumab groups versus placebo across antecedent-exposure groups. Greater proportions of ustekinumab- than placebo-treated patients (all p<0.05) had clinically meaningful improvements in HAQ-DI (≥0.3), DLQI (≥5), and SF-36 (≥5) scores at wk24, irrespective of drug exposure. Improvements in pain, disease activity, and impact of disease on productivity were similar, and benefits were maintained through wk52. Conclusions: Significant improvements in PROs with ustekinumab vs. placebo were observed in three antecedent-exposure populations of PsA patients, including those with prior MTX and anti-TNF use

The Effects of Active Labour Market Policies for Immigrants Receiving Social Assistance in Denmark

We estimate the effect of active labour market programmes on the exit rate to regular employment for non-western immigrants in Denmark who receive social assistance. We use the timing-of-events duration model and rich administrative data. We find large positive post-programme effects, and, surprisingly, even most in-programme effects are positive. The effects are largest for subsidized employment programmes, but effects are also large and significant for direct employment programmes and other programmes. The effects are larger if programmes begin after six months of unemployment. Implications of our estimates are illustrated by calculating effects on the duration to regular employment over a five-year period.programme evaluation, duration analysis, timing-of-events model