Utnyttja belysningen effektivt

I norra Europa är ljuset helt otillräckligt för odling under vinterhalvåret och ibland även på sommaren. Artificiell belysning har därför blivit allt vanligare inte bara vid odling av småplantor och krukväxter utan även för året-runt-produktion av olika grönsaker i växthus. Utvecklingen har gått från glödlampor, neonrör och kvicksilverlampor via metallhalogen till högtrycksnatriumlampor (HPS) som är dominerande än idag alltsedan 1970-talet. Stigande energipriser och ökande krav på miljöhänsyn har gjort att det idag finns ett stort behov av att effektivisera användandet av belysning i växthus. Tekniken utvecklas stadigt, HPS-lamporna har undan för undan fått allt bättre effektivitet med införandet av 600 och 1000 W lampor samt elektroniska drivdon. Dessutom har helt nya lamptyper som t.ex. LED-lampor och plasmalampor kommit på marknaden. Det finns dock mycket man kan göra för att effektivisera sin användning av belysning utan att nödvändigtvis göra en dyr investering i att byta hela utrustningen

Citizens, bribery and the propensity to protest

It is widely assumed that the more one experiences corruption the more likely one is to want to protest about it. Yet empirical evidence illustrating this is thin on the ground. This paper fills that gap by focusing on the extent to which self-reported experience of bribery affects the willingness to engage in protests against corruption in Africa. We find that the more one experiences bribery the more one is likely to support anti-corruption protests. A further unexpected finding is that the personal experience of corruption also increases the willingness to rely on bribes to solve public administration problems

The International-Trade Network: Gravity Equations and Topological Properties

This paper begins to explore the determinants of the topological properties of the international - trade network (ITN). We fit bilateral-trade flows using a standard gravity equation to build a "residual" ITN where trade-link weights are depurated from geographical distance, size, border effects, trade agreements, and so on. We then compare the topological properties of the original and residual ITNs. We find that the residual ITN displays, unlike the original one, marked signatures of a complex system, and is characterized by a very different topological architecture. Whereas the original ITN is geographically clustered and organized around a few large-sized hubs, the residual ITN displays many small-sized but trade-oriented countries that, independently of their geographical position, either play the role of local hubs or attract large and rich countries in relatively complex trade-interaction patterns

Modelling production-consumption flows of goods in Europe: the trade model within Transtools3

The paper presents a new model for trade flows in Europe that is integrated with a logistics model for transport chain choice through Logsum variables. Logsums measures accessibility across an entire multi-modal logistical chain, and are calculated from a logistics model that has been estimated on disaggregated micro data and then used as an input variable in the trade model. Using Logsums in a trade model is new in applied large-scale freight models, where previous models have simply relied on the distance (e.g. crow-fly) between zones. This linkage of accessibility to the trade model makes it possible to evaluate how changes in policies on transport costs and changes in multi-modal networks will influence trade patterns. As an example the paper presents outcomes for a European-wide truck tolling scenario, which showcases to which extent trade is influenced by such a policy. The paper discusses how such a complex model can be estimated and considers the choice of mathematical formulation and the link between the trade model and logistics model. In the outcomes for the tolling scenario we decompose the total effects into effects from the trade model and effects from the logistics model

Relativistic nature of a magnetoelectric modulus of Cr_2O_3-crystals: a new 4-dimensional pseudoscalar and its measurement

Earlier, the magnetoelectric effect of chromium sesquioxide Cr_2O_3 has been determined experimentally as a function of temperature. One measures the electric field-induced magnetization on Cr_2O_3 crystals or the magnetic field-induced polarization. From the magnetoelectric moduli of Cr_2O_3 we extract a 4-dimensional relativistic invariant pseudoscalar $\widetilde{\alpha}$. It is temperature dependent and of the order of 10^{-4}/Z_0, with Z_0 as vacuum impedance. We show that the new pseudoscalar is odd under parity transformation and odd under time inversion. Moreover, $\widetilde{\alpha}$ is for Cr_2O_3 what Tellegen's gyrator is for two port theory, the axion field for axion electrodynamics, and the PEMC (perfect electromagnetic conductor) for electrical engineering.Comment: Revtex, 36 pages, 9 figures (submitted in low resolution, better quality figures are available from the authors

Alpha-fetoprotein-producing primary lung carcinoma: A case report

Alpha-fetoprotein (AFP)-producing lung adenocarcinoma is a rare type of lung cancer, with its characteristics not yet fully clarified. We recently encountered a case of this type of lung cancer. The patient was a 69-year-old man who consulted an internist with the chief complaint of epigastric pain. Chest X-ray and CT revealed a lobulated mass measuring 70 mm in diameter in the right lower lung field and a metastasis in the right hilar lymph nodes. Of the tumor markers, the serum AFP was elevated (4620 ng/ml), and the serum carcinoembryonic antigen and carbohydrate antigen 19-9 were also slightly elevated. Transbronchial lung biopsy revealed the diagnosis of lung cancer. Under thoracoscopic assistance, right lower lobectomy + mediastinal lymph node dissection was carried out. Immunostaining showed the tumor cells to be AFP-positive. The tumor was thus diagnosed as an AFP-producing lung adenocarcinoma. The patient followed an uneventful clinical course after the surgery, with serum AFP decreasing to the normal range by about 2 weeks after the surgery. As of this writing, no sign of tumor recurrence has been noted. This case is presented here with a review of the literature

Unexpected Role of α-Fetoprotein in Spermatogenesis

BACKGROUND: Heat shock severely affects sperm production (spermatogenesis) and results in a rapid loss of haploid germ cells, or in other words, sperm formation (spermiogenesis) is inhibited. However, the mechanisms behind the effects of heat shock on spermatogenesis are obscure. METHODOLOGY/PRINCIPAL FINDINGS: To identify the inhibitory factor of spermiogenesis, experimental cryptorchid (EC) mice were used in this study. Here we show that α-fetoprotein (AFP) is specifically expressed in the testes of EC mice by proteome analysis. AFP was also specifically localized spermatocytes by immunohistochemical analysis and was secreted into the circulation system of EC mice by immunoblot analysis. Since spermatogenesis of an advanced mammal cannot be reproduced with in vitro, we performed the microinjection of AFP into the seminiferous tubules of normal mice to determine whether AFP inhibits spermiogenesis in vivo. AFP was directly responsible for the block in spermiogenesis of normal mice. To investigate whether AFP inhibits cell differentiation in other models, using EC mice we performed a partial hepatectomy (PH) that triggers a rapid regenerative response in the remnant liver tissue. We also found that liver regeneration is inhibited in EC mice with PH. The result suggests that AFP released into the blood of EC mice regulates liver regeneration by inhibiting the cell division of hepatocytes. CONCLUSIONS/SIGNIFICANCE: AFP is a well-known cancer-specific marker, but AFP has no known function in healthy human beings. Our findings indicate that AFP expressed under EC conditions plays a role as a regulatory factor in spermatogenesis and in hepatic generation