1,836 research outputs found
Jahrestagung der Gesellschaft für Medizinische Ausbildung ; Ruhr-Universität Bochum ; 23.-25. September 2010 ; Tagungsband ; Viel verändert - viel erreicht? Bilanz und Zukunft der Studienreformen
No full textOntwerp basisdocument Tolueen
No full textBetreft de engelse editie van rapport nr. 758473005. Bij
dit rapport behoort een bijlage getiteld Appendix to integrated criteria
document toluene, effectsDit rapport bevat een systematisch overzicht en een kritische evaluatie van de belangrijkste gegevens over de prioritaire stof tolueen ten behoeve van het effectgericht milieubeleid.Abstract not availableDGM/SR /Cornet J
De duurzaamheid van de Nederlandse landbouw : 1950 – 2015 – 2040
No full textThe purpose of this thesis is: to provide a theoretical model with which the performance of agriculture (summarized in the concept of sustainability) can be assessed; to visualize the development of the sustainability of agriculture in the period from 1950 to 2015; giving an outline of an agricultural system that is sustainable, can provide food security and can meet the climate objectives. In this thesis sustainability is defined as producing goods and services with as little as possible energy, raw materials and land use and causing as less as possible negative effects on the environment. Sustainability has been calculated based on the following parameters: the energetic value of the output and input of agriculture; direct and indirect land use; direct and indirect labour. The energetic value of the output has been calculated based on the weights of the yield of the products and the energetic value of the agricultural products (the metabolic energy). The energetic value of the input has been calculated based on the quantities of the used energy and raw materials and their embodied energy. The direct land use is the quantity of agricultural land in the Netherlands. The indirect land use is the area of land needed for winning, producing and distributing the input. Direct labour concerns the workers on the farms in the Netherlands. Indirect labour is the labour needed for producing the input. Indirect land use and indirect labour can be deployed in the Netherlands or elsewhere. The non-nutritive greenhouse horticulture has not been taken into consideration here. After formulating the theoretical framework the research questions have been formulated plus the concepts used in this thesis and the methodology and way of working. The theoretical framework is conceptualized based on the production factors land, labour and capital. The performance of agriculture has been measured so far based on the productivity of labour, whereby a number of things are ignored. Measuring the performance based on sustainability, as defined in this thesis, meets these objections. Indicated is that the concepts EROEI (Energy Return On Energy Investment) and Net Energy are important to judge the future energy supply. The input is calculated based on the following 12 topics: the direct and indirect use of energy, the latter of which consists of mining, greenhouses, other buildings, tractors and machinery, cattle feeder, animal manure, fertilizer, pesticides, electronics, services and transport and infrastructure. For every kind of input also (as far as possible) the indirect land use and the indirect labour are calculated. Since 1950 agricultural production (output) in the Netherlands has increased. With less people and less farms the production in 2015 is higher than in 1950. The quantity of used input has increased faster than the production (output). The ratio between output and input decreases between 1950 and 2015. In the same period direct land use decreases and indirect land use increases. The same applies to labour: direct labour decreases and indirect labour increases. In 1950 direct land use and direct labour are larger than indirect land use and indirect labour; in 2015 it is the other way round. The maintenance of soil fertility is important for agriculture and for food quality. Food quality has declined in recent decades. This is because organic matter and nutrients are not reused in a cycle, but are lost due to the way in which residues are processed now. It has been ascertained whether Dutch agriculture can feed its own population. Based on the Health Council directive 2015 the required amounts of food for the Dutch population have been calculated and on this base the required area of agricultural land. It appears that not enough food can be produced. The calculated quantities of animal products have been reduced to 50% and in that situation there would be enough food. The desirability reusing raw materials has been elaborated by examining whether all residual flows of organic material in agriculture makes a sufficient fertilization level of the agricultural land possible. That appears to be the case, but then there must come a (for a large part) new collection structure for all residual flows of organic materials. This allows the cycle to be closed and a further deterioration of soil fertility and food quality can be avoided. The social costs of agriculture has partly been calculated on the basis of greenhouse gas emissions in CO2-equivalents. These costs were compared with the social costs as calculated in a number of studies. The orders of magnitude are similar. The social costs of agriculture calculated here are 4.5 billion euros (based on the FAO price for CO2) and vary from 2 billion euros to 11.7 billion euros (based on the price for CO2 of CPB and PBL). The greenhouse gas emissions of agriculture in 2015 amounted to 39,064,800 tons of CO2 equivalents. Social costs are not only caused by the emissions in CO2-equivalents, but also by other factors. Based on FAO-studies a range is indicated of the total social costs from 5 to 20 billion euros. Price ratios between labour and energy and raw materials are now such that they opt for replacing labour by capital. This has been worked out in an example. Calculations based on energetic values do not (always) run parallel to those based on money. When making decisions this aspect is often underexposed. The export balance of food agriculture is approximately 13 billion euros. The net added value at factor costs has been fallen by 21% after inflation correction in the period from 1950 to 2015. In 2015 the calculated social costs of agriculture vary between lower and much higher than the net added value at factor costs, which then amounted to 6.9 billion euros. The question arises then whether the present agriculture is still a useful activity both in a social and economical way. In order to meet the climate targets, as formulated in the Paris agreement, these have been translated to Dutch agriculture. Subsequently, a number of starting points were determined for agriculture in the future, with as the guiding principle the year 2040 chosen. Based on a number of preconditions, as stated for the year 2040, a drastic reduction of the use of energy and raw materials should take place. This is only possible on a large scale if capital will be replaced by labour on a large scale. Also exports and imports must then be kept to a minimum. In order to visualize this development, a number of data on agriculture for the period 1950 to 2040 have been determined. The main conclusions of this research are: the sustainability of agriculture has declined sharply from 1950 to 2015 and should increase in the period from 2016 to 2050. This necessitates a large influx of labour into agriculture (reruralisation). In doing so the picture of agriculture in 2040 will deviate strongly from that in 2015 and in some respects look a bit like agriculture in 1950; direct land use has decreased by 495.000 ha (21%) in the period 1950 to 2015 and indirect land use has increased with 2,8 million ha; direct labour has decreased by more than 407.000 f.t.e. in the period 1950 to 2015 and indirect labour has increased with 102.000 f.t.e.; an increase in the energetic value of the input in GJ/ha of 619% in the period 1950 to 2015 results in a relatively small increase of the output in GJ/ha by 12%; all resources deployed in the period 1950 to 2015 to increase production bear no reasonable relation to the realized revenue increase present agriculture must quickly be transformed into a sustainable agriculture. In order to display the amounts of energy in this thesis the PJ (PetaJoule) unit is used when it concerns large quantities (national level) and the GJ (GigaJoule) unit is used when it comes to energy quantities at company level or per ton or per ha. Table 92 provides a survey of the most important results. Table 92 Output in weight and energy, input in energy, land use and labour 1950 1980 2010 2015 2040 population NL 10.200.280 14.091.000 16.486.000 16.900.726 17.000.000 number of farms 410.000 145.000 72.000 64.000 172.000 average farm size 5,7 ha 13,9 ha 25,9 ha 28,8 ha 10,5 ha direct land use 2.336.766 ha 2.016.171 ha 1.867.054 ha 1.841.362 ha 1.800.000 ha indirect land use 381.632 ha 3.413.584 ha 2.910.840 ha 3.178.688 ha 250.000 ha total land use 2.718.398 ha 5.429.755 ha 4.777.894 ha 5.020.050 ha 2.050.000 ha direct labour 520.422 f.t.e. 223.422 f.t.e. 122.998 f.t.e. 113.099 f.t.e. 583.500 f.t.e. indirect labour 85.932 f.t.e. 192.365 f.t.e. 170.770 f.t.e. 188.416 f.t.e. 100.000 f.t.e. total labour 606.354 f.t.e. 415.787 f.t.e. 293.768 f.t.e. 301.515 f.t.e. 683.500 f.t.e. output, input total output (weight) 16 mln. ton 33 mln. ton 38 mln. ton 39 mln. ton 10 mln. ton output (energy) 65 PJ 114 PJ 133 PJ 135 PJ 66 PJ input (energy) 54 PJ 215 PJ 271 PJ 305 PJ 30 PJ output/input 1,20 0,53 0,49 0,44 2,18 output, input per ha output in ton/ha 5,91 ton/ha 6,06 ton/ha 7,95 ton/ha 7,83 ton/ha 5,04 ton/ha output in GJ/ha 23,886 GJ/ha 21,028 GJ/ha 27,827GJ/ha 26,821 GJ/ha 31,969 GJ/ha input in GJ/ha 23,021 GJ/ha 106,530 GJ/ha 145,383GJ/ha 165,636GJ/ha 16,667 GJ/ha output/input 1,04 0,20 0,19 0,16 1,92 output/ton product 4,039 GJ/ton 3,472 GJ/ton 3,502 GJ/ton 3,432 GJ/ton 6,339 GJ/ton input/ton product 3,346 GJ/ton 6,531 GJ/ton 7,149 GJ/ton 7,760 GJ/ton 2,902 GJ/ton For a relatively small increase in yields per ha (50% in tons and 12% in GJ) in the period 1950 to 2015, the input per ha increased by 619% and 2.8 million ha of additional land was used elsewhere. For this increase in production land consolidation and land use projects have been carried out over an area of more than 1.3 million ha. The question can be asked whether the costs are not much higher than the benefits. Many costs could have been avoided if the switch to sustainable agriculture had been made earlier. The results for the year 2040 should be seen as an outline for a sustainable agricultural system. It is not possible to wait until price ratios between the production factors are such that the choice is made for the use of fewer raw materials and energy and more labour. We can’t wait so long, because an entire infrastructure needs to be changed. Additional policy measures must be used to accelerate the transition to a sustainable agriculture. The government must set a good example in its own actions and no longer make any investments that make the climate problem worse (such as roads and airports). Research must also be tuned to achieve a low input agriculture. By making specific the preconditions that are demanded from agriculture (and society as a whole) because of the climate problem, this thesis shows how agriculture has developed in the period 1950-2015 and how sustainable agriculture with a low input of energy and raw materials and a recovery of the cycle of organic and inorganic substances could be in 2040. With this thesis a contribution is delivered to the way of thinking about the necessary transition of our agriculture. This does not alter the fact that now soon starting a drastic conversion of agriculture is very urgent
Fitting the Cusp Catastrophe in R: A cusp Package Primer
No full textOf the seven elementary catastrophes in catastrophe theory, the âÂÂcuspâ model is the most widely applied. Most applications are however qualitative. Quantitative techniques for catastrophe modeling have been developed, but so far the limited availability of flexible software has hindered quantitative assessment. We present a package that implements and extends the method of Cobb (Cobb and Watson'80; Cobb, Koppstein, and Chen'83), and makes it easy to quantitatively fit and compare different cusp catastrophe models in a statistically principled way. After a short introduction to the cusp catastrophe, we demonstrate the package with two instructive examples.
Welche Gründe benennen Studierende für die Wahl der Krankenhäuser für Ihre Einsätze im Praktischen Jahr? Eine quantitative Inhaltsanalyse
No full textAim: In the final (practical) year (PY), students have the opportunity to become familiar with their potential future place of work. At the same time, university hospitals and teaching hospitals compete to recruit the best junior staff from this pool. The aim of this study is to present students' selection criteria for the location of the final year in detail. Methods: On the formal evaluation of the final year at the Mannheim Medical Faculty, students were asked after each training period which reasons led to the selection of the location. Thirty-one subcategories were formed from the free-text responses, sorted according to their controllability and then grouped into 11 main categories. The Mannheim University Hospital introduced an expense allowance in November 2015. The data from the period before and after its introduction, the reasons given for choosing the location for the compulsory and elective subjects, and the reasons given for choosing a teaching hospital or university hospital were evaluated and compared separately.Results: A total of 1,164 questionnaires were evaluated from the period before the introduction of the expense allowance, and 1,120 questionnaires were evaluated from the period after the introduction. Overall, Proximity (19%), Financial incentives (18%) and Subject (18%) were the most frequently cited reasons. The Financial incentives subcategory was the most frequent in period 1 (32%), but lost relevance in period 2 (6%). In contrast, Recommendation gained in importance (from 8% to 15%). A comparison of the lead categories shows that teaching hospitals benefit more from their public image and university hospitals more from the subjects they offer.Conclusion: Students primarily choose the location for their final year for pragmatic reasons, such as Incentives and Living environment, but the Public image of the hospitals also plays a significant role. The frequency of the reasons given differs between compulsory and elective subjects, as well as between university hospitals and teaching hospitals. The results can help to improve the attractiveness of the location in a targeted manner and to present a specific image to the public.Ziel: Studierende haben im Praktischen Jahr (PJ) die Möglichkeit, ihren potentiellen späteren Arbeitsplatz kennenzulernen. Gleichzeitig konkurrieren Universitätsklinika und Lehrkrankenhäuser bei der Rekrutierung des passenden Nachwuchses aus diesem Pool. Ziel dieser Studie ist, die Auswahlkriterien der Studierenden für die Einsatzorte im PJ differenziert darzustellen. Methodik: Im Rahmen der regulären schriftlichen PJ-Evaluation an der Medizinischen Fakultät Mannheim wurden PJ-Studierende nach jedem Ausbildungsabschnitt gefragt, welche Gründe zur Wahl des Einsatzortes geführt haben. Aus den Freitextantworten wurden 31 Subkategorien gebildet, hinsichtlich ihrer Beeinflussbarkeit geordnet und zu elf Leitkategorien zusammengefasst. Am Universitätsklinikum Mannheim wurde im November 2015 die Zahlung einer Aufwandsentschädigung eingeführt. Die Daten aus der Zeitspanne vor und nach Einführung der Aufwandsentschädigungen, die genannten Gründe für die Wahl des Einsatzortes für die Pflicht- und Wahlfächer sowie für die Einsatzorte Lehrkrankenhaus und Universitätsklinikum wurden jeweils getrennt ausgewertet und verglichen.Ergebnisse: Aus der Zeitspanne vor Einführung der Aufwandsentschädigung wurden 1.164 Fragebögen und aus der Zeitspanne nach Einführung wurden 1.120 Fragebögen ausgewertet. Insgesamt wurden Nähe (19%), Finanzielle Anreize (18%) und Fach (18%) am häufigsten als Gründe genannt. Die Subkategorie Finanzielle Anreize war in Zeitspanne 1 am häufigsten (32%), verlor aber in Zeitspanne 2 (6%) an Relevanz. Hingegen konnten Empfehlungen an Bedeutung (von 8% auf 15%) gewinnen. Beim Vergleich der Leitkategorien ist ersichtlich, dass Lehrkrankenhäuser stärker von der Außendarstellung und Universitätskliniken stärker von dem jeweils angebotenen Fach profitieren.Schlussfolgerung: Studierende wählen den Einsatzort in erster Linie nach pragmatischen Gründen wie Anreize und Lebensumfeld aus, aber auch die Außendarstellung der Einsatzorte spielt eine erhebliche Rolle. Die Häufigkeit der angegebenen Gründe unterscheiden sich sowohl zwischen Pflicht- und Wahlfächern als auch zwischen Universitätsklinikum und Lehrkrankenhäusern. Die Ergebnisse können Kliniken dabei unterstützen, die Attraktivität des Einsatzortes gezielt zu verbessern und nach außen darzustellen
Comparison of termite assemblages along a landuse gradient on peat areas in Sarawak, Malaysia.
No full textVAESSEN T, VERWER C, DEMIES M, KALIANG H & VAN DER MEER PJ. 2011. Comparison of termite assemblages along a landuse gradient on peat areas in Sarawak, Malaysia. In this study we assessed the species density and relative abundance of termites in peat land in Sarawak, Malaysia. Termites were sampled in near-natural peat swamp forest, logged-over peat swamp forest, young oil palm plantation and a cleared and burned site. Species density and relative abundance were calculated for each site. Both species density and relative abundance differed significantly between sites. Near-natural peat swamp forest had the highest termite density, followed by logged-over peat swamp forest, young oil palm plantation and the cleared site. In contrast, the relative abundance of termites was highest in the young oil palm plantation due to the omnipresent genus Schedorhinotermes. Most of the species found in the cleared site and young oil palm plantation did not occur at the other sites. We conclude that ongoing forest degradation and conversion in tropical peat land result in shifting termite assemblages and declining species density. Species that originally occur at low densities in peat swamp forests are typically lost as a result of peat swamp forest conversion
Simplivariate Models: Ideas and First Examples
No full textOne of the new expanding areas in functional genomics is metabolomics: measuring the metabolome of an organism. Data being generated in metabolomics studies are very diverse in nature depending on the design underlying the experiment. Traditionally, variation in measurements is conceptually broken down in systematic variation and noise where the latter contains, e.g. technical variation. There is increasing evidence that this distinction does not hold (or is too simple) for metabolomics data. A more useful distinction is in terms of informative and non-informative variation where informative relates to the problem being studied. In most common methods for analyzing metabolomics (or any other high-dimensional x-omics) data this distinction is ignored thereby severely hampering the results of the analysis. This leads to poorly interpretable models and may even obscure the relevant biological information. We developed a framework from first data analysis principles by explicitly formulating the problem of analyzing metabolomics data in terms of informative and non-informative parts. This framework allows for flexible interactions with the biologists involved in formulating prior knowledge of underlying structures. The basic idea is that the informative parts of the complex metabolomics data are approximated by simple components with a biological meaning, e.g. in terms of metabolic pathways or their regulation. Hence, we termed the framework ‘simplivariate models’ which constitutes a new way of looking at metabolomics data. The framework is given in its full generality and exemplified with two methods, IDR analysis and plaid modeling, that fit into the framework. Using this strategy of ‘divide and conquer’, we show that meaningful simplivariate models can be obtained using a real-life microbial metabolomics data set. For instance, one of the simple components contained all the measured intermediates of the Krebs cycle of E. coli. Moreover, these simplivariate models were able to uncover regulatory mechanisms present in the phenylalanine biosynthesis route of E. col
Seasonal diet changes in elephant and impala in mopane woodland
No full textElephant and impala as intermediate feeders, having a mixed diet of grass and browse, respond to seasonal fluctuations of forage quality by changing their diet composition. We tested the hypotheses that (1) the decrease in forage quality is accompanied by a change in diet from more monocots in the wet season to more dicots in the dry season and that that change is more pronounced and faster in impala than in elephant; (2) mopane (Colophospermum mopane), the most abundant dicot species, is the most important species in the elephant diet in mopane woodland, whereas impala feed relatively less on mopane due to the high condensed tannin concentration; and (3) impala on nutrient-rich soils have a diet consisting of more grass and change later to diet of more browse than impala on nutrient-poor soils. The phosphorus content and in vitro digestibility of monocots decreased and the NDF content increased significantly towards the end of the wet season, whereas in dicots no significant trend could be detected. We argue that this decreasing monocot quality caused elephant and impala to consume more dicots in the dry season. Elephant changed their diet gradually over a 16-week period from 70% to 25% monocots, whereas impala changed diets rapidly (2-4 weeks) from 95% to 70% monocots. For both elephants and impala, there was a positive correlation between percentage of monocots and dicots in the diet and the in vitro digestibility of these forage items. Mopane was the most important dicot species in the elephant diet and its contribution to the diet increased significantly in the dry season, whereas impala selected other dicot species. On nutrient-rich gabbroic soils, impala ate significantly more monocots than impala from nutrient-poor granitic soils, which was related to the higher in vitro digestibility of the monocots on gabbroic soil. Digestibility of food items appears to be an important determinant of diet change from the wet to the dry season in impala and elephants
Abstract P1-13-10: Adjuvant treatment of HER2+ breast cancer: Should trastuzumab be given sequentially or concurrently with chemotherapy?
No full textAbstract
Background
Human Epidermal growth factor Receptor 2 positive (HER2+) breast cancers have a high risk of recurrence in the absence of systemic treatment. The monoclonal antibody trastuzumab in combination with chemotherapy has significantly improved survival. Randomized trials have given trastuzumab both concurrently and sequentially with chemotherapy. To date, only one study reported a comparison between concurrent and sequential trastuzumab, with a numerically but not statistically significant benefit for concurrent use.
Our aim is to evaluate whether there is a difference in survival between patients who received trastuzumab sequentially to chemotherapy compared to concurrently with chemotherapy using data from the population-based, Netherlands Cancer Registry (NCR).
Methods
All women diagnosed in the Netherlands with a HER2+, TanyNanyM0 breast tumor between 2005 and 2007 who received both chemotherapy and trastuzumab were identified from the NCR.
Kaplan Meier survival estimates and Cox regression were used to compare recurrence free survival (RFS) and overall survival (OS) by trastuzumab sequence. Hazard ratios (HR) were adjusted for grade, pathological T-stage, pathological N-stage, estrogen receptor (ER), progesterone receptor, radiotherapy, hormonal therapy and ovarian ablation.
Results
A total of 1,849 patients were identified, with a mean follow-up of 7.8 years. Of these, 1,260 received concurrent trastuzumab and 589 sequential trastuzumab. Most tumors were grade 3, node positive and ER+. During follow-up 358 RFS events occurred, 231 in the concurrently treated patients compared to 127 in sequentially treated patients. Regarding OS, 290 deaths were observed, 188 deaths in concurrently treated patients compared to 102 deaths in sequentially treated patients, respectively.
OS and RFS were similar among sequentially versus concurrently treated patients (adjusted HR 1.11; 95% CI 0.87-1.42; P=0.420 and adjusted HR 1.15; 95% CI 0.92-1.44; P=0.209, respectively).
Conclusion
We observed no significant difference in OS and RFS between patients who received sequential trastuzumab compared to patients treated concurrently. Based on our results no recommendation can be made favoring either of the two treatment sequences for the adjuvant treatment of HER2+ breast cancer patients.
Citation Format: Dackus GMHE, Jóźwiak K, Van der Wall E, Van Diest PJ, Hauptmann M, Siesling S, Sonke GS, Linn SC. Adjuvant treatment of HER2+ breast cancer: Should trastuzumab be given sequentially or concurrently with chemotherapy? [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-13-10.</jats:p
Drugs in sport — testing results from the South African Laboratory 1995 - 2002
No full textObjective. To summarise the results of the past 8 years obtained at the South African Doping Control Laboratory and to compare the results with international statistics.
Method. Screening procedures were performed on 14 017 urine samples collected from competitors in 54 different sporting codes during the period 1995 - 2002. Samples were analysed using gas chromatography and gas chromatography/mass spectrometry for the presence of prohibited substances, which are listed by the International Olympic Committee (IOC).
Results. The results obtained were compared with those of the IOC-accredited laboratories. Prohibited substances were detected in 300 samples (2.14%), of which 45.6% contained anabolic agents and 34.6% stimulants. The positive samples from the IOC laboratories contained 58.7% anabolic agents and 20.8% stimulants. Testosterone and nandrolone were the anabolic agents most frequently detected in positive samples, both in South Africa and internationally. The ephedrines as a group accounted for most stimulants detected in positive samples.
Conclusion. It is of concern that the percentage of positive samples (2.14%) obtained in our laboratory is higher than the 1.70% in IOC laboratories. It is therefore necessary that doping control to curb the use of prohibited substances should continue and expand.
South African Journal of Sports Medicine Vol.16(1) 2004: 29-3
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