Assessing climate forcings of the Earth system for the past millennium

[1] The effects of natural and anthropogenic forcings (solar activity, volcanism, atmospheric CO2 concentration, deforestation) on climate changes are estimated with the Earth system model of intermediate complexity, CLIMBER-2, for the past millennium. Simulated surface air temperatures for the Northern Hemisphere from the combined forcing correlate reasonably well with paleoclimatic data (r = 0.70). The largest negative anomalies occur when insolation minima coincide with volcanic eruptions. Anthropogenic forcings impose additional climate changes after 1850. The increasing warming from increasing CO2 concentrations is attenuated by the cooling effect from deforestation. Results from differently combined forcings suggest that the relatively cool climate in the second half of 19th century is largely attributable to cooling from deforestation

The influence of dust optical properties on the colour of simulated MSG-SEVIRI Desert Dust infrared imagery

Satellite imagery of atmospheric mineral dust is sensitive to the optical properties of the dust, governed by the mineral refractive indices, particle size, and particle shape. In infrared channels the imagery is also sensitive to the dust layer height and to the surface and atmospheric environment. Simulations of mineral dust in infrared "Desert Dust" imagery from the Spinning Enhanced Visible and InfraRed Imager (SEVIRI) have been performed, using the COSMO-MUSCAT (COSMO: COnsortium for Small-scale MOdelling; MUSCAT: MUltiScale Chemistry Aerosol Transport Model) dust transport model and the Radiative Transfer for TOVS (RTTOV) program, in order to investigate the sensitivity of the imagery to assumed dust properties. This paper introduces the technique and performs initial validation and comparisons with SEVIRI measurements over North Africa for daytime hours during 6 months covering June and July of 2011–2013. Using T-matrix scattering theory and assuming the dust particles to be spherical or spheroidal, wavelength- and size-dependent dust extinction values are calculated for a number of different dust refractive index databases, along with several values of the particle aspect ratio, denoting the particle shape. The consequences for the infrared extinction values of both the particle shape and the particle orientation are explored: this analysis shows that as the particle asphericity increases, the extinctions increase if the particles are aligned horizontally, and decrease if they are aligned vertically. Randomly oriented spheroidal particles have very similar infrared extinction properties as spherical particles, whereas the horizontally and vertically aligned particles can be considered to be the upper and lower bounds on the extinction values. Inputting these values into COSMO-MUSCAT-RTTOV, it is found that spherical particles do not appear to be sufficient to describe fully the resultant colour of the dust in the infrared imagery. Comparisons of SEVIRI and simulation colours indicate that of the dust types tested, the dust refractive index dataset produced by Volz (1973) shows the most similarity in the colour response to dust in the SEVIRI imagery, although the simulations have a smaller range of colour than do the observations. It is also found that the thermal imagery is most sensitive to intermediately sized particles (radii between 0.9 and 2.6µm): larger particles are present in too small a concentration in the simulations, as well as with insufficient contrast in extinction between wavelength channels, to have much ability to perturb the resultant colour in the SEVIRI dust imagery

The EarthCARE satellite: the next step forward in global measurements of clouds, aerosols, precipitation, and radiation

The collective representation within global models of aerosol, cloud, precipitation, and their radiative properties remains unsatisfactory. They constitute the largest source of uncertainty in predictions of climatic change and hamper the ability of numerical weather prediction models to forecast high-impact weather events. The joint European Space Agency (ESA)–Japan Aerospace Exploration Agency (JAXA) Earth Clouds, Aerosol and Radiation Explorer (EarthCARE) satellite mission, scheduled for launch in 2018, will help to resolve these weaknesses by providing global profiles of cloud, aerosol, precipitation, and associated radiative properties inferred from a combination of measurements made by its collocated active and passive sensors. EarthCARE will improve our understanding of cloud and aerosol processes by extending the invaluable dataset acquired by the A-Train satellites CloudSat, Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO), and Aqua. Specifically, EarthCARE’s cloud profiling radar, with 7 dB more sensitivity than CloudSat, will detect more thin clouds and its Doppler capability will provide novel information on convection, precipitating ice particle, and raindrop fall speeds. EarthCARE’s 355-nm high-spectral-resolution lidar will measure directly and accurately cloud and aerosol extinction and optical depth. Combining this with backscatter and polarization information should lead to an unprecedented ability to identify aerosol type. The multispectral imager will provide a context for, and the ability to construct, the cloud and aerosol distribution in 3D domains around the narrow 2D retrieved cross section. The consistency of the retrievals will be assessed to within a target of ±10 W m–2 on the (10 km)2 scale by comparing the multiview broadband radiometer observations to the top-of-atmosphere fluxes estimated by 3D radiative transfer models acting on retrieved 3D domains

Minimal-invasive Chirurgie. Aspekte der chirurgischen Onkologie des Gastrointestinaltrakts [Minimal invasive surgery. Aspects of surgical oncology of the gastrointestinal tract]

The general potential and current position of minimally invasive surgery for the surgical treatment of malignant tumours of the gastrointestinal tract are discussed. A reliable validation of these procedures for tumour surgery is still impossible due to the lack of long-term results, the selective experience, and the ongoing process of learning and development. However, it seems clear that minimally invasive procedures will have an important position within surgical oncology. This is especially true with respect to improved staging of gastrointestinal tumours by laparoscopy and various palliative procedures that may be performed laparoscopically. Minimally invasive procedures may suffice for the treatment of certain, highly selected cases of preneoplastic and early cancerous lesions. The definitive acceptance of minimally invasive procedures in the future will require further clinical, preferably randomised trials, comparing the advantages of the minimally invasive access route to possible long-term disadvantages with regard to recurrence-free and overall survival

Construct validity testing of a laparoscopic surgery simulator (Lap Mentor((R))) : Evaluation of surgical skill with a virtual laparoscopic training simulator

BACKGROUND: Before surgical simulators can be implemented for assessment of surgical training, their construct validity should be assessed. METHODS: Nine novices (NOV), nine medical students (MS), and nine residents (RES) underwent a laparoscopic skills training on the virtual reality (VR) simulator Lap Mentor((R)). Assessment of laparoscopic skill was based on parameters measured by the computer system before and after training. RESULTS: Significant difference existed between RES and NOV at seven of nine tasks before training on the VR simulator. After the training in some tasks significant differences were observed between the experienced group (RES) and the nonexperienced groups (MS and NOV) or between medical groups (RES and MS) and nonmedical group (NOV). CONCLUSIONS: Performance parameters of the Lap-Mentor((R)) can be used to distinguish between subjects with varying laparoscopic experience

Neue Diagnoseverfahren beim Mammakarzinom : Bedeutung fuer die operative Therapie

Die zeitgemaeße Therapie des Mamma-karzinoms wird durch Bemuehungen um eine zunehmende Individualisierung der Vorgehensweisen bestimmt. Individuelle Konzepte erfordern allerdings eine exakte und moeglichst differenzierte Erfassung Therapie- und Prognoserelevanter Eigenschaften des jeweiligen individuellen Krankheitszustands. Hierzu gehoeren das biologische Verhalten des Primaertumors ebenso wie seine lokale (intramammaere) Ausbreitung und das Muster lymphatischer und haematogener Metastasierung. Nicht zuletzt aufgrund der stagnierenden Heilungsraten besteht ein nicht unerheblicher Handlungsdruck, in dieser Richtung Fortschritte zu erzielen. Neue Entwicklungen zur differenzierten Tumorausbreitungsdiagnostik in Brustdruese und Axilla mit dem Ziel, die chirurgische Behandlung ebenso wie die perioperative Zusatztherapie in ihrem Ausmaß angemessen zu steuern, sollen daher nachfolgend eroertert werden

The sensitivity of the colour of dust in MSG-SEVIRI Desert Dust infrared composite imagery to surface and atmospheric conditions

Infrared “Desert Dust” composite imagery taken by the Spinning Enhanced Visible and InfraRed Imager (SEVIRI), onboard the Meteosat Second Generation (MSG) series of satellites above the equatorial East Atlantic, has been widely used for more than a decade to identify and track the presence of dust storms from and over the Sahara Desert, the Middle East, and southern Africa. Dust is characterised by distinctive pink colours in the Desert Dust false-colour imagery; however, the precise colour is influenced by numerous environmental properties, such as the surface thermal emissivity and skin temperature, the atmospheric water vapour content, the quantity and height of dust in the atmosphere, and the infrared optical properties of the dust itself. For this paper, simulations of SEVIRI infrared measurements and imagery have been performed using a modelling system, which combines dust concentrations simulated by the aerosol transport model COSMO-MUSCAT (COSMO: COnsortium for Small-scale MOdelling; MUSCAT: MUltiScale Chemistry Aerosol Transport Model) with radiative transfer simulations from the RTTOV (Radiative Transfer for TOVS) model. Investigating the sensitivity of the synthetic infrared imagery to the environmental properties over a 6-month summertime period from 2011 to 2013, it is confirmed that water vapour is a major control on the apparent colour of dust, obscuring its presence when the moisture content is high. Of the three SEVIRI channels used in the imagery (8.7, 10.8, and 12.0 µm), the channel at 10.8 µm has the highest atmospheric transmittance and is therefore the most sensitive to the surface skin temperature. A direct consequence of this sensitivity is that the background desert surface exhibits a strong diurnal cycle in colour, with light blue colours possible during the day and purple hues prevalent at night. In dusty scenes, the clearest pink colours arise from high-altitude dust in dry atmospheres. Elevated dust influences the dust colour primarily by reducing the contrast in atmospheric transmittance above the dust layer between the SEVIRI channels at 10.8 and 12.0 µm, thereby boosting red and pink colours in the imagery. Hence, the higher the dust altitude, the higher the threshold column moisture needed for dust to be obscured in the imagery: for a sample of dust simulated to have an aerosol optical depth (AOD) at 550 nm of 2–3 at an altitude of 3–4 km, the characteristic colour of the dust may only be impaired when the total column water vapour is particularly moist (⪆39 mm). Meanwhile, dust close to the surface (altitude <1 km) is only likely to be apparent when the atmosphere is particularly dry and when the surface is particularly hot, requiring column moisture ⪅13 mm and skin temperatures ⪆314 K, and is highly unlikely to be apparent when the skin temperature is ⪅300 K. Such low-altitude dust will regularly be almost invisible within the imagery, since it will usually be beneath much of the atmospheric water vapour column. It is clear that the interpretation of satellite-derived dust imagery is greatly aided by knowledge of the background environment

Lymphatic mapping and sentinel lymph node biopsy in epidermoid carcinoma of the anal canal

AIM: Although 15-25% of patients with anal cancer present with superficial inguinal lymph node metastases but the routine application of groin irradiation is controversial because of serious side effects. Inguinal sentinel lymph node biopsy (SLNB) can be used to select patients appropriately for inguinal radiation. The study evaluates the efficiency and clinical impact of SLNB. METHODS: Forty patients with anal cancer underwent 1ml Tc(99m)-Nanocolloid injection in four sites around the tumour. Patients with inguinal radio colloid enrichment were selected for sentinel lymph node biopsy (SLNB). Lymph node status was examined by haematoxylin and eosin (H&E) as well as immunohistochemistry-staining. All SLN-positive patients were scheduled for inguinal radiation; SLN-negative patients with T1 and early T2 tumours were not scheduled for inguinal radiation. RESULTS: SLN were detected in 36/40 patients. Three common patterns of lymphatic drainage were observed: mesenterial, iliacal and inguinal. Twenty patients with inguinal SLN underwent SLN-biopsy. 6/20 patients were SLN-positive. In 10/20 patients SLNB altered the therapy plan - four patients with T1-tumours and positive SLN had additional groin irradiation, whereas 6 patients with small T2-tumors and tumour-free inguinal SLN did not undergo inguinal irradiation. CONCLUSIONS: Inguinal sentinel node biopsy in anal cancer is efficient and could assist in the decision for inguinal radiation. The validity and safety of the proposed therapeutic algorithm has to be proven by a larger, prospective study

Prediction of gastric cancer lymph node status by sentinel lymph node biopsy and the Maruyama computer model

Aims The extent of lymph node dissection in gastric cancer remains controversial. The Maruyama computer model and the sentinel lymph node biopsy (SLNB) are compared for their value to predict the nodal status and lead to stage-adapted surgery. Methods Thirty four patients with stage I–IV gastric cancer underwent both staging procedures. For SLNB, 15 patients underwent endoscopic, peri-tumoural injection of 99mTc-colloid, and 19 patients were injected of Patent blue V®. All ‘hot’ or blue sentinel lymph nodes (SLNs) were separately excised and histopathologically assessed. If the SLN was negative after routine staining by H&E, it was processed completely and reanalysed after immunohistochemistry. Results At least, one SLN was detected by means of SLNB in 33/34 of the patients. The sensitivity to identify a positive nodal status was 22/33 and the specificity/positive predictive value was 10/10 and 22/22. Additional micrometastases or isolated tumour cells in the SLN led to ‘upstaging’ of 5/15, initially classified as nodal negative by H&E-staining. Using the Maruyama computer model, a sensitivity of 22/23 for the correct prediction of the lymph node involvement was associated with a specificity of 2/10 and a positive predictive value of 22/30. Conclusions The clinical impact of the Maruyama computer model is limited due to low specificity and a low positive predictive value, rendering the method less useful as an indicator for individualised surgery