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Very-high-energy (VHE), heavy ions are of particular interest for single event effects (SEEs) testing due to their combination of high linear energy transfer (LET) and high penetration within electronics components. The dosimetry of such beams poses an important challenge for facilities aiming to provide VHE ions for radiation effects testing. In this article, ion beam dosimetry using a silicon solid state detector is presented for uranium ions in the 100–1000 MeV per nucleon kinetic energy range. The study involves a combination of experimental measurements carried out at the SIS18 accelerator at Gesellschaft für Schwerionenforschung (GSI) and Monte Carlo (MC) simulation studies using FLUktuierende KAskade (FLUKA). Particular emphasis was put on the physical basis of interaction between both primary beam particles as well as secondary fragments, and the detector device. Our results demonstrate an excellent capability of understanding key beam properties and extracting the LET through comparison with simulation results. This benchmark study acts as a reference for developing and utilizing a heavy ion electronics testing infrastructure currently under development at Conseil Européen pour la Recherche Nucléaire (CERN).

Genetic testing has familial implications. Counsellors find themselves in (moral) conflict between medical confidentiality (towards the patient) and a potential right or even duty to warn at-risk relatives. Legal regulations vary between countries. English literature about German law is scarce. We reviewed the literature of relevant legal cases, focussing on German law, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. This article aims to familiarise counsellors with their responsibilities, compare the situation between countries and point out legally unresolved areas.According to the German Genetic Diagnostics Act (Gendiagnostikgesetz) in case of an ‘avoidable or treatable’ genetic disorder, geneticists ought to confine themselves to the obligated advice to the patient. Whether a breach of the duty of confidentiality can be justified in exceptional cases by ‘necessity as justification’ for actively informing relatives at risk remains legally unclear. In case of a ‘neither avoidable nor treatable’ genetic disease, geneticists should also refrain from actively informing relatives as the justifiable state of emergency does not permit to break the duty of confidentiality.

Food systems contribute considerably to greenhouse gas (GHG) emissions and influence land use. In Germany, many strategies have been proposed by policy-makers to reduce negative impacts and make the food system more sustainable. It is unclear how close the suggested policies, when bundled, will bring the food and land use system towards the targeted goals; and what stakeholders from non-policy-making organizations consider realistic changes in the German food system. We thus surveyed different stakeholder groups on their opinions about realistic changes in the food and land use system in Germany up to 2050, developed four stakeholder pathways, and used an accounting tool to determine the effect of each pathway on indicators such as land use, GHG emissions, and biodiversity conservation potential. The assessment showed that GHG emissions from agricultural activities and land use are reduced from 66 to − 2–22 TgCO2e by 2050, while the area where natural processes predominate increases from 19 to 27–32%, and the resilience of the food system is not negatively influenced. The change is caused mainly by a diet-change-induced reduction of livestock production and agricultural area transformation into areas with higher carbon sequestration rates. If followed, the common stakeholder pathway (based on all stakeholder responses) would thus lead towards a sustainable food and land use system, but only if the underlying assumption of a drastic diet change towards more plant-based products comes true. Stakeholders from the academic and public sectors were more likely to assume that such a change was realistic than stakeholders from the private sector.

Isolated ventral and dorsal rat spinal roots incubated in normal (2.5 mM) or high glucose (25 mM) concentrations or in high concentrations of other hexoses were exposed transiently to hypoxia (30 min) in a solution of low buffering power. Compound nerve action potentials, extracellular direct current potentials, and interstitial pH were continuously recorded before, during, and after hypoxia. Ventral roots incubated in 25 MM D-glucose showed resistance to hypoxia. Dorsal roots, on the other hand, revealed electrophysiological damage by hyperglycemic hypoxia as indicated by a lack of posthypoxic recovery. In both types of spinal roots, interstitial acidification was most pronounced during hyperglycemic hypoxia. The changes in the sensitivity to hypoxia induced by high concentrations Of D-glucose were imitated by high concentrations of D-mannose. In contrast, D-galactose, L-glucose, D-fructose, and L-fucose did not have such effects. Resistance to hypoxia, hypoxia-generated interstitial acidification, and hypoxia-induced electrophysiological damage were absent after pharmacological inhibition of nerve glycolysis with iodoacetate. These observations indicate 1) that enhanced anaerobic glycolysis produces resistance to hypoxia in hyperglycemic peripheral nerves and 2) that acidification may impair the function of peripheral axons when anaerobic glycolysis proceeds in a tissue with reduced buffering power. Diabetes 42:981-87, 1993, Resistance to ischemia and liability to ischemic lesions are characteristics of peripheral nerves in diabetic patients (1,2). However, the precise mechanisms underlying these alterations are not yet clear. Resistance to [...]

The risk assessment quantities called lifetime attributable risk (LAR) and risk of exposure-induced cancer (REIC) are used to calculate the cumulative cancer incidence risks for astronauts, attributable to radiation exposure accumulated during long term lunar and Mars missions. These risk quantities are based on the most recently published epidemiological data on the Life Span Study (LSS) of Japanese A-bomb survivors, who were exposed to γ-rays and neutrons. In order to analyze the impact of a different neutron RBE on the risk quantities, a model for the neutron relative biological effectiveness (RBE) relative to gammas in the LSS is developed based on an older dataset with less follow-up time. Since both risk quantities are based on uncertain quantities, such as survival curves, and REIC includes deterministic radiation induced non-cancer mortality risks, modelled with data based on the general population, the risks for astronauts may not be optimally estimated. The suitability of these risk assessment measures for the use of cancer risk calculation for astronauts is discussed. The work presented here shows that the use of a higher neutron RBE than the value of 10, traditionally used in the LSS risk models, can reduce the risks up to almost 50%. Additionally, including an excess absolute risk (EAR) baseline scaling also increases the risks by between 0.4% and 8.1% for the space missions considered in this study. Using just an EAR model instead of an equally weighted EAR and excess relative risk (ERR) model can decrease the cumulative risks for the considered missions by between 0.4% and 4.1% if no EAR baseline scaling is applied. If EAR baseline scaling is included, the calculated risks with the EAR- and the mixed model, as well as the risks calculated with just the ERR model are almost identical and only small differences in the uncertainties are visible.

Recently, variants in DONSONhave been reported to cause different disorders of the microcephalic primordial dwarfism spectrum. Using whole-exome sequencing, we identified two novel, compound heterozygous DONSONvariants in a pair of siblings, one of whom was previously diagnosed with Fanconi anemia. This occurred because the present cases exhibited clinical findings in addition to those of the microcephalic primordial dwarfism disorder, including severe limb malformations. These findings suggest that the DONSONand Fanconi anemia proteins could have supplementary roles in developmental processes as they have in the maintenance of genomic integrity, resulting in related disease phenotypes.

A plethora of treatment options have been described for canine meningoencephalitis of unknown origin (MUO), yet a gold standard has not been established. The aim of this prospective pilot study was to document the effect of a newly designed 30 Gray (Gy) radiation therapy (RT) protocol plus corticosteroids as treatment for focal and multifocal MUO, to monitor clinical and imaging changes during the course of the disease with conventional magnetic resonance imaging (MRI) and proton MR Spectroscopy (H-1 MRS) and to detect the occurrence of radiation related side effects. Six dogs (3 with focal and 3 with multifocal lesions) were included in the study. The RT protocol used consisted of 30 Gy in 10 fractions. The neurological status of all six dogs improved during RT, with 3 of 6 cases returning to a normal condition. One dog was euthanized early during follow-up (<3 weeks after end of RT). Three month follow up MRI was normal in one dog and improved in 3 dogs and H-1 MRS normalized in 4. In the dog without improvement of the MRI lesions, the N-acetyl aspartate continued to decrease, while choline and creatine concentrations remained stable during that time. This dog was euthanized 18 month after the end of RT due to relapse. One dog was lost to follow up 12 month after completion of RT. The other 3 dogs are still alive at the time of writing. RT with 30 Gy in 10 fractions can provide an additional option for anti-inflammatory treatment of focal and multifocal MUO. The protocol used for treatment monitoring was feasible while no side effects of RT could be observed during the follow up period. Moreover, H-1 MRS could represent a new and non-invasive tool to control the progression of the disease during the treatment course.

Aminal attraction: The combination of indium(I) chloride and a chiral silver binol phosphate provides an excellent catalyst for asymmetric Hosomi–Sakurai reactions between N,O‐aminals and boronates (see scheme; PG=protecting group, pin=pinacolato). The substrate scope includes aromatic, heteroaromatic, and aliphatic N,O‐aminals as well as allyl and allenyl boronates.

We have recently uncovered a general indium(I)‐catalyzed method for allylations and propargylation of acetals and ketals with a water‐ and air‐stable allyl boronate. By using a more reactive allyl borane, we have successfully extended this methodology to the more challenging CC coupling with ethers. Herein, we report an improved methodology for the indium(I)‐catalyzed allylation of acetals and ethers, through combination of the allyl boronate with a commercially available “hard” Lewis acid, B‐methoxy‐9‐BBN (BBN=borabicyclo[3.3.1]nonane), as an effective co‐catalyst. Significantly, our work highlights for the first time the correlation between the Lewis acidity of “electrophilic” boron‐based compounds and their “nucleophilic” reactivity in Csp3–Csp3couplings, catalyzed by a “soft” low‐oxidation main group metal. In addition, we also report several applications of these methodologies to the selective synthesis of various carbohydrate derivatives.

The unprecedented use of a soluble organoindium species, indiumIII hexamethyldisilazide InIIIhmds3, for catalytic carboncarbon bond formations between ketones and boronates, is reported. Various functionalized tertiary homoallyl alcohols were generated easily in high yields. Remarkably, free hydroxy and primary amine functionalities proved to be tolerated. A rate acceleration and markedly improved diastereoselectivities were observed in the presence of methanol. Based on preliminary NMR experiments and the αselectivity with an αsubstituted boronate, we assume the in situgeneration of reactive allylindiumIII species through catalytic borontoindium transmetalation.

Tolerabel: Bei der ersten asymmetrischen Indium(I)‐Katalyse erwies sich ein System aus InI und einem chiralen Semicorrin‐Liganden (L*) als wirkungsvoller Katalysator für die enantioselektive Allylierung, Crotylierung und α‐Chlorallylierung von Hydrazonen. In den beiden zuletzt genannten Fällen verläuft die C‐C‐Verknüpfung hoch selektiv, ohne dass die reaktiven O‐H‐ bzw. C‐Cl‐Bindungen angegriffen werden. pin=Pinakol.

We have uncovered Pd0‐catalyzed intermolecular nonsymmetrical Suzuki–Miyaura‐type sp3–sp3C–C bond formations between allyl carbonates and nontoxic allyl, allenyl, or propargyl boronates. This report represents the first use of these types of boronic esters in this particular context. The present transformations proceeded with high selectivity under remarkably mild conditions, and various functional groups including an aldehyde function proved to be compatible. In addition, several boronates were found to display very unusual reactivity patterns; the higher reactivity of boron as apposed to silicon was clearly demonstrated as well. Finally, the inherent problem of β‐hydride elimination associated with intermediary allyl–Pd species was addressed by employing a commercially available Ni0catalyst.

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Background and Purpose:: There is concern about the increase of radiation-induced malignancies with the application of modern radiation treatment techniques such as intensity-modulated radiotherapy (IMRT) and proton radiotherapy. Therefore, X-ray scatter and neutron radiation as well as the impact of the primary dose distribution on secondary cancer incidence are analyzed.Material and Methods:: The organ equivalent dose (OED) concept with a linear-exponential and a plateau dose-response curve was applied to dose distributions of 30 patients who received radiation therapy of prostate cancer. Three-dimensional conformal radiotherapy was used in eleven patients, another eleven patients received IMRT with 6-MV photons, and eight patients were treated with spot-scanned protons. The treatment plans were recalculated with 15-MV and 18-MV photons. Secondary cancer risk was estimated based on the OED for the different treatment techniques.Results:: A modest increase of 15% radiation-induced cancer results from IMRT using low energies (6 MV), compared to conventional four-field planning with 15-MV photons (plateau dose-response: 1%). The probability to develop a secondary cancer increases with IMRT of higher energies by 20% and 60% for 15 MV and 18 MV, respectively (plateau dose-response: 2% and 30%). The use of spot-scanned protons can reduce secondary cancer incidence as much as 50% (independent of dose-response).Conclusion:: By including the primary dose distribution into the analysis of radiation-induced cancer incidence, the resulting increase in risk for secondary cancer using modern treatment techniques such as IMRT is not as dramatic as expected from earlier studies. By using 6-MV photons, only a moderate risk increase is expected. Spot-scanned protons are the treatment of choice in regard to secondary cancer incidence.

AbstractWe investigated how the complexity of fetal heart rate fluctuations (fHRF) is related to the sleep states in sheep and human fetuses. The complexity as a function of time scale for fetal heart rate data for 7 sheep and 27 human fetuses was estimated in rapid eye movement (REM) and non-REM sleep by means of permutation entropy and the associated Kullback-Leibler entropy. We found that in humans, fHRF complexity is higher in non-REM than REM sleep, whereas in sheep this relationship is reversed. To show this relation, choice of the appropriate time scale is crucial. In sheep fetuses, we found differences in the complexity of fHRF between REM and non-REM sleep only for larger time scales (above 2.5 s), whereas in human fetuses the complexity was clearly different between REM and non-REM sleep over the whole range of time scales. This may be due to inherent time scales of complexity, which reflect species-specific functions of the autonomic nervous system. Such differences have to be considered when animal data are translated to the human situation.

It is often assumed that radiation-induced secondary cancer after proton therapy forms preferentially close to the distal fall-off of the spread-out Bragg peak because of an increased relative biological effectiveness (RBE) with regard to cancer induction of low-energy protons. In this study we analyze to what extent dose gradients distal to the Planning Target Volume (PTV) may, independently from the RBE, contribute to enhanced radiation carcinogenesis. The study is based on two dogs which, out of 30 dogs treated with proton therapy at the Paul Scherrer Institute (PSI), developed a secondary cancer. Both dogs were originally diagnosed and treated for a fibrosarcoma and developed an osteosarcoma 48 and almost 60 months, respectively, after radiotherapy. From the dose distributions of the initial radiotherapy for both dogs three-dimensional maps of secondary cancer complication probability (SCCP) were computed. The SCCP maps were analyzed in the regions where the dogs developed a secondary cancer. The SCCP maps showed an enhanced risk in the regions of the femur where the secondary cancers were detected, as compared to the SCCP of the total femur. Excess risk of radiation-induced cancer at the distal part of proton radiation fields can thus be explained using SCCP calculations on the basis of the physical dose distributions. Therefore, the occurrence of secondary cancer close to the distal dose gradients of proton therapy is not necessarily due to an increased RBE of low-energy protons. More extensive studies based on more patients will be necessary to further elucidate the factors influencing the development of secondary tumors.It is often assumed that radiation-induced secondary cancer after proton therapy forms preferentially close to the distal fall-off of the spread-out Bragg peak because of an increased relative biological effectiveness (RBE) with regard to cancer induction of low-energy protons. In this study we analyze to what extent dose gradients distal to the Planning Target Volume (PTV) may, independently from the RBE, contribute to enhanced radiation carcinogenesis. The study is based on two dogs which, out of 30 dogs treated with proton therapy at the Paul Scherrer Institute (PSI), developed a secondary cancer. Both dogs were originally diagnosed and treated for a fibrosarcoma and developed an osteosarcoma 48 and almost 60 months, respectively, after radiotherapy. From the dose distributions of the initial radiotherapy for both dogs three-dimensional maps of secondary cancer complication probability (SCCP) were computed. The SCCP maps were analyzed in the regions where the dogs developed a secondary cancer. The SCCP maps showed an enhanced risk in the regions of the femur where the secondary cancers were detected, as compared to the SCCP of the total femur. Excess risk of radiation-induced cancer at the distal part of proton radiation fields can thus be explained using SCCP calculations on the basis of the physical dose distributions. Therefore, the occurrence of secondary cancer close to the distal dose gradients of proton therapy is not necessarily due to an increased RBE of low-energy protons. More extensive studies based on more patients will be necessary to further elucidate the factors influencing the development of secondary tumors.

The highly selective preparation of various types of allenic and homopropargylic hydrazides through regiospecific allenylation and propargylation of the corresponding N-acylhydrazones is reported. These carbon-carbon bond-forming reactions employing in situ prepared propargyl- and allenyltrichlorosilanes proceed smoothly in N,N-dimethylformamide (DMF) without any metal catalysis (neutral Lewis base activation of nucleophiles). The use of Hünig's base as an additive is beneficial in terms of chemical yields.

A commercial electron beam treatment planning system on the basis of a Monte Carlo algorithm (Varian Eclipse, eMC V7.2.35) was evaluated. Measured dose distributions were used for comparison with dose distributions predicted by eMC calculations. Tests were carried out for various applicators and field sizes, irregular shaped cut outs and an inhomogeneity phantom for energies between 6 MeV and 22 MeV. Monitor units were calculated for all applicator/energy combinations and field sizes down to 3 cm diameter and source-to-surface distances of 100 cm and 110 cm. A mass-density-to-Hounsfield-Units calibration was performed to compare dose distributions calculated with a default and an individual calibration. The relationship between calculation parameters of the eMC and the resulting dose distribution was studied in detail. Finally, the algorithm was also applied to a clinical case (boost treatment of the breast) to reveal possible problems in the implementation.

In adjuvant treatment for breast cancer there is no tool available with which to measure the efficacy of the therapy. In contrast, in neoadjuvant therapy reduction in tumour size is used as an indicator of the sensitivity of tumour cells to the agents applied. If circulating epithelial (tumour) cells can be shown to react to therapy in the same way as the primary tumour, then this response may be exploited to monitor the effect of therapy in the adjuvant setting. We used MAINTRAC®analysis to monitor the reduction in circulating epithelial cells during the first three to four cycles of neoadjuvant therapy in 30 breast cancer patients. MAINTRAC®analysis revealed a patient-specific response. Comparison of this response with the decline in size of the primary tumour showed that the reduction in number of circulating epithelial cells accurately predicted final tumour reduction at surgery if the entire neoadjuvant regimen consisted of chemotherapy. However, the response of the circulating tumour cells was unable to predict the response to additional antibody therapy. The response of circulating epithelial cells faithfully reflects the response of the whole tumour to adjuvant therapy, indicating that these cells may be considered part of the tumour and can be used for therapy monitoring.

Abstract: Estimates of secondary cancer risk after radiotherapy are becoming more important for comparative treatment planning. Modern treatment planning systems provide accurate three-dimensional (3D) dose distributions for each individual patient. The dose distributions can be converted into organ equivalent doses to describe radiation-induced cancer after radiotherapy (OEDrad-ther) in the irradiated organs. The OEDrad-ther concept assumes that any two dose distributions in an organ are equivalent if they cause the same radiation-induced cancer risk. In this work, this concept is applied to dose–response relationships, which are leveling off at high dose. The organ-dependent operational parameter of this dose–response relationship was estimated by analyzing secondary cancer incidence data of patients with Hodgkin’s disease. The dose distributions of a typical radiotherapy treatment plan for treating Hodgkin’s disease was reconstructed. Dose distributions were calculated in individual organs from which cancer incidence data were available. The model parameter was obtained by comparing dose and cancer incidence rates for the individual organs.

Die vorliegende Studie rekonstruiert mit Hilfe bislang nicht ausgewerteter Archivalien die Entstehungsgeschichte der ungedruckt gebliebenen Textsammlung Jahrbuch für realistische Dichtung(1887), für die Hermann Conradi und Otto Erich Hartleben als Herausgeber zeichnen sollten. Dieses Projekt stellt eine direkte Fortsetzung der berühmten Lyrikanthologie Moderne Dichter-Charaktere(1885) dar, in der sich die junge Generation naturalistischer Autoren erstmals weitgehend geschlossen zu Wort meldete. Anhand der hier vorgelegten Materialien läßt sich nicht nur der Entwicklungsverlauf der naturalistischen Bewegung genauer als bisher nachzeichnen, auch die scharfe Konkurrenzsituation der Schriftsteller innerhalb des sich herausbildenden Gruppenzusammenhangs tritt nun sehr viel klarer hervor.

Insoluble polystyrene grafted compounds of the type (PH)(1−t){P(CH2)nSnBupCl3−p}t, (PH)(1−t){P(CH2)nSnBuO}tand (PH)(1−t)[{P(CH2)nSnBuCl}2O]t/2, in which (PH) is a cross‐linked polystyrene; n=4, 6, and 11; p=0 and 1; and tthe degree of functionalisation, were synthesised from Amberlite XE‐305, a polystyrene cross‐linked with divinylbenzene. The compounds were characterised by using elemental analysis, and IR, Raman, solid‐state 117Sn NMR, and 1H and 119Sn high‐resolution MAS NMR spectroscopy. The influence of the spacer length and the tin functionality on the catalytic activity of these compounds, as well as their recycling ability, was assessed in the transesterification reaction of ethyl acetate with various alcohols. These studies showed significant differences in the activity of the catalysts interpreted in terms of changes in the mobility of the catalytic centres. Some of the supported catalysts could be recycled at least seven times without noticeable loss of activity. The residual tin content in the reaction products was found to be as low as 3 ppm.

Estimates of secondary cancer risk after radiotherapy are becoming more important for comparative treatment planning. There is great uncertainty concerning the dose-response relationship for radiation-induced carcinogenesis at doses higher than 4 Gy. The purpose of this report is to determine a simple dose-response relationship for secondary cancer incidence after radiotherapy treatment which can be used for comparative treatment planning. In this report a simple one-parameter model to estimate the complication probability of secondary cancer was fitted to literature data on secondary cancer incidence after radiotherapy. The results showed a linear dose-response relationship in the low-dose part and an exponentially decreasing one after a maximum at around 10 Gy. The observed dose-response relationship and the literature data used to fit the dose-response indicate that cell death effects are important for the explanation of secondary cancer incidence. Even using a dose and dose-rate effectiveness factor (DDREF) of two (instead of one), a cancer incidence maximum is observed at around 10 Gy, with decreasing incidence at higher doses.

Vor dem Hintergrund der notwendigen Revision der Kriterien zur Vergabe des Gütezeichens „Blauer Engel“ für Laserdrucker, Kopierer und Multifunktionsgeräte mussten auch die Prüfmethoden angepasst werden, da die alten Verfahren nicht mehr die heutigen Anforderungen an Emissionsmessungen erfüllen. In diesem Zusammenhang wurde auch das unterschiedliche Emissionsverhalten von Hardcopy-Geräten auf Grund der verschiedenen und nicht miteinander vergleichbaren Prüfverfahren heftig diskutiert. Aus diesen Gründen wurde ein neues Prüfverfahren entwickelt, mit dem eine verlässliche und reproduzierbare Prüfung der Emissionsraten von Staub, Ozon und flüchtigen organischen Verbindungen auf der Basis des ECMA (European Computer Manufacturer Association) Standards 328 möglich ist. Dazu wurden neun verschiedene Geräte unter verschiedenen Bedingungen untersucht. Als ein Ergebnis dieser Studie wurden neue Kriterien zur Vergabe des „Blauen Engels“ für Kopierer, Drucker und Multifunktionsgeräte festgelegt.

The purpose of this investigation is to measure the impact of Ti-alloy-prostheses on the neutron dose during proton and photon radiotherapy. Such unwanted neutron dose to the patient should be kept as low as possible (ALARA principle), as such additional dose can create secondary malignancies. For this purpose we performed neutron dose measurements using etch track detectors under the same conditions on a proton and a photon beam line used for radiotherapy. We found no influence of the prostheses material on the neutron dose both for proton and photon treatment.

The synthesis of C-4-alkylated pyrrolidin-3-one 5 was achieved by regio- and diastereoselective alkylation of chiral hydrazone 8 with electrophile 7 followed by selective deprotection. Highly functionalised compound 5 is the first key intermediate in our approach towards a new asymmetric total synthesis of (-)-quinocarcin (1) and related structural analogues 2 and 3.

To analyse the physiologic development of fetal cardiac time intervals throughout gestation using fetal magnetocardiography (FMCG). FMCG data of 163 uncomplicated pregnancies (19th and 42nd gestational week) were analysed. Mean value, standard deviation, minimum and maximum of the duration of the P-wave, the QRS-complex, the PR and the QT-interval were plotted against gestational age. QRS-complex, P wave and QT-interval showed a significant lengthening between the 20th and 42nd gestational week. The mean of the QRS complex raised from 36±4.7 ms (week 21–24) up to 48±5.2 ms (37th week), (p=0.0001). The mean of the P-wave was between 47±5.9 ms (week 21–24) and 53±9.5 ms (37th week), (p=0.05) and the mean of the QT-interval was 198±18 ms (week 21–24) and increased up to 244±23.9 ms (37th week), (p=0.009). The PR-interval did not show a correlation with gestational age. FMCG provides sufficient information about all parts of the fetal cardiac conduction system from the 19th gestational week on. It offers the possibility to analyse the shape and the duration of the PQRST-complex. Copyright © 2002 John Wiley & Sons, Ltd.

Objective To assess the maturation of auditory evoked cortical responses in the human fetus using fetal magnetoencephalography.

Magnetoencephalography (MEG) using auditory evoked cortical fields (AEF) is an absolutely non-invasive method of passive measurement which utilizes magnetic fields caused by specific cortical activity. By applying the exceptionally sensitive SQUID technology to record these fields of dipolar configuration produced by the fetal brain, MEG as an investigational tool could provide new insights into the development of the human brain in utero. The major constraint to this application is a very low signal-to-noise ratio (SNR) that has to be attributed to a variety of factors including the magnetic signals generated by the fetal and maternal hearts which inevitably obscure a straightforward signal analysis. By applying a new algorithm of specific heart artefact reduction based on the relative regularity of the heart signals, we were able to increase the chance of extracting a fetal AEF from the raw data by the means of averaging techniques and principle component analysis. Results from 27 pregnant, healthy women (third trimester of their uncomplicated pregnancy) indicate an improved detection rate and the reproducibility of the fetal MEG. We evaluate and discuss a-priori criteria for signal analyses which will enable us to systematically analyze additional limiting factors, to further enhance the efficiency of this method and to promote the assessment of its possible clinical value in the future.

International agreements are likely to stimulate greenhouse gas mitigation efforts. Agriculture can participate either as a source of emission reductions or as a sink for gas emission storage. Emission trading markets are likely to emerge where agriculture could sell emission offsets. Several agricultural opportunities are available at a cost of $10–25 per ton carbon dioxide. Abatement costs for non-agricultural industries have been estimated to be as much as $200–250 per ton carbon dioxide. In the longer run, agricultures role may diminish because many agricultural strategies offer only one-time gains and non-agricultural emitters may lower costs through technical change.

Chlorinated trans stilbenes bind with high affinity to the cytosolic Ah receptor from Wistar rat liver. The EC50 values for competition with [3H]-2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) cover a range from 10-400 nM, but with no apparent relationship between molecular structure and binding activity. These compounds induce monooxygenase enzyme activity in rat hepatoma H-4-II E cells in culture only weakly, again with no apparent dependence on molecular structure, and the weakest enzyme inducers act as antagonists for the induction of these enzymes by TCDD. In vivo administration of 3,3',4,4'-tetrachloro-tans-stilbene in the rat leads to decreased Ah receptor levels.