Beiträge zur Taxonomie der Gattung Sempervivum L. (Crasssulaceae) unter besonderer Berücksichtigung der in Kleinasien vorkommenden Sippen

Die Taxa der Gattung Sempervivum, die in der Türkei, Georgien, Armenien und im Iran vorkommen, werden in dieser Revision bearbeitet. Die Problematik um die systematische Stellung der Sektion Jovibarba zu Sempervivum s. str. wird diskutiert. Die Morphologie der Gattung wird ausführlich dargestellt, wobei besonderes Augenmerk auf das Indument gerichtet ist. Hinsichtlich der Gattungsgliederung wird das ökologische Artkonzept“ zu Grunde gelegt. Die Speziation (Artbildung) findet besondere Beachtung. Dabei wird herausgestellt, dass neben präzygotischen Isolations-Barrieren ökologische und saisonale Isolation die bestimmenden Faktoren der Artbildung in der Gattung sind. Neben allopatrischer und sympatrischer, dürfte auch die Hybridisierung an der Artbildung beteiligt sein. Die Chorologie der Gattung sowie der einzelnen Arten wird beschrieben und durch Verbreitungskarten illustriert. Die Abspaltung der Gattung innerhalb der Crassulaceae wird mit der alpidischen Faltung in Zusammenhang gebracht. Im Hinblick auf die Phylogeografie – speziell der türkischen Sippen - kann postuliert werden, dass die größte Artenvielfalt mit der pleistozänen Überformung des Reliefs durch das Inlandeis korreliert. Die Sippen der Türkei und der angrenzenden Gebiete zeigen vertikale Verbreitungsschwerpunkte oberhalb der 2000 m-Isohypse. Die disjunkte Verbreitung folgt den Höhenstufen,modifiziert durch die im Pleistozän und Pliozän erfolgten Prozesse. Vier Areale stellen die Verbreitungsschwerpunkte im Gebiet dar: Zentralanatolien, Mittel-Nordanatolien, Nordostanatolien und Inner-Ostanatolien. Artenreichstes Areal ist Nordostanatolien. Dieser Befund korreliert mit pleistozänen Prozessen und dem aktuellen Klima. In Mittel-Nordanatolien bewirkt die geringe Reliefenergie ein auf wenige Räume beschränkte, insulare Verbreitung. In Zentralanatolien liegt der Verbreitungsschwerpunkt auf die im Südosten gelegenen „Erciyas-Karacadağ Vulkanberg-Zone“. Inner-Ostanatolien wurde von pleistozänem und pliozänem Vulkanismus überformt. Ein Einwandern der Sippen nach diesen Ereignissen wird diskutiert und die geringe Artenvielfalt auf Gründereffekte zurückgeführt. Die in der Türkei und in den angrenzenden Räumen vorkommen Taxa werden beschrieben und illustriert und deren Verbreitung ausführlich diskutiert

Fire models and methods to map fuel types: The role of remote sensing.

Understanding fire is essential to improving forest management strategies. More specifically, an accurate knowledge of the spatial distribution of fuels is critical when analyzing, modelling and predicting fire behaviour. First, we review the main concepts and terminology associated with forest fuels and a number of fuel type classifications. Second, we summarize the main techniques employed to map fuel types starting with the most traditional approaches, such as field work, aerial photo interpretation or ecological modelling. We pay special attention to more contemporary techniques, which involve the use of remote sensing systems. In general, remote sensing systems are low-priced, can be regularly updated and are less time-consuming than traditional methods, but they are still facing important limitations. Recent work has shown that the integration of different sources of information andmethods in a complementary way helps to overcome most of these limitations. Further research is encouraged to develop novel and enhanced remote sensing techniques

Finding a path for REDD+ between ODA and the CDM

A new financing mechanism known as REDD+ (reducing emissions from deforestation and forest degradation, and conservation, sustainable management of forests and enhancement of forest carbon stocks) is being established to achieve large-scale reductions inGHGemissions from tropical forestry and land use. Can REDD+ successfully integrate an emphasis on sustainable development benefits (as with Official Development Assistance, ODA) with a focus on delivering emission reductions (as with the Clean Development Mechanism, CDM)? It is argued that there is a real risk that REDD+ will stay too close to ODA and fail to move beyond its ‘readiness’ phase. Moreover, as with the CDM, there could be an over-emphasis on results in terms of emission reductions, which would only make it attractive for a small set of activities in relatively few countries. In order to balance sustainable development with cost-effective emission reductions, REDD+ needs to involve the private sector in project implementation and financing, its rules for reference levels and crediting arrangements need to be flexible, and forest countries need to proactively direct activities

Avaliação do potencial da interferometria sar para o mapeamento altimétrico de áreas reflorestadas por eucalyptus sp

Este trabalho tem como objetivo avaliar a qualidade altimétrica dos modelos de elevação (MDE) gerados através da interferometria SAR Synthetic Aperture Radar nas bandas X e P, em diferentes polarizações em áreas florestadas. Este estudo foi realizado no município de Pindamonhangaba/SP, em uma área caracterizada por reflorestamento de Eucalyptus saligna de 6 anos de idade, cujo inventario florestal e levantamento topográfico foram realizados no mesmo período do aerolevantamento. Verificou-se que nesta área florestada o modelo de elevação da superfície do dossel empregando a interferometria na banda X, gerou produtos cartográficos de precisão inferior a esperada, com desvio padrão na ordem 2,7 metros. A utilização de um modelo de regressão, que combinou a coerência interferométrica e o MDE, compensou os erros de medida da altura da vegetação, melhorando a qualidade do produto cartográfico para desvio padrão da ordem de 1,4 metro atingindo a resolução altimétrica desejada. Os modelos de elevação do terreno na banda P, polarização HH, em áreas florestadas apresentaram similaridade com os dados do levantamento topográfico, com desvio padrão na ordem de 1,97 metro, devido à maior penetração do feixe do radar na floresta de Eucalyptus e conseqüentemente uma maior interação com o solo do que com as árvores. O modelo de elevação do solo na banda X em áreas de pasto apresentou um desvio padrão de 0,6 metro, cuja escala de mapeamento foi compatível com a resolução empregada, enquanto que os modelos de elevação na banda P apresentaram um valor de desvio padrão de 6 a 20 metros conforme a polarização, devido ao espalhamento especular, causando uma baixa relação sinal/ruído

Predicting survival after pulmonary metastasectomy for colorectal cancer: previous liver metastases matter

BACKGROUND: Few patients with lung metastases from colorectal cancer (CRC) are candidates for surgical therapy with a curative intent, and it is currently impossible to identify those who may benefit the most from thoracotomy. The aim of this study was to determine the impact of various parameters on survival after pulmonary metastasectomy for CRC. METHODS: We performed a retrospective analysis of 40 consecutive patients (median age 63.5 [range 33-82] years) who underwent resection of pulmonary metastases from CRC in our institution from 1996 to 2009. RESULTS: Median follow-up was 33 (range 4-139) months. Twenty-four (60%) patients did not have previous liver metastases before undergoing lung surgery. Median disease-free interval between primary colorectal tumor and development of lung metastases was 32.5 months. 3- and 5-year overall survival after thoracotomy was 70.1% and 43.4%, respectively. In multivariate analysis, the following parameters were correlated with tumor recurrence after thoracotomy; a history of previous liver metastases (HR = 3.8, 95%CI 1.4-9.8); and lung surgery other than wedge resection (HR = 3.0, 95%CI 1.1-7.8). Prior resection of liver metastases was also correlated with an increased risk of death (HR = 5.1, 95% CI 1.1-24.8, p = 0.04). Median survival after thoracotomy was 87 (range 34-139) months in the group of patients without liver metastases versus 40 (range 28-51) months in patients who had undergone prior hepatectomy (p = 0.09). CONCLUSION: The main parameter associated with poor outcome after lung resection of CRC metastases is a history of liver metastases

The strengths and limitations of routine staging before treatment with abdominal CT in colorectal cancer

<p>Abstract</p> <p>Background</p> <p>Advanced colorectal cancer (CRC), either locally advanced, metastasized (mCRC) or both, is present in a relevant proportion of patients. The chances on curation of advanced CRC are continuously improving with modern multi-modality treatment options. For incurable CRC the focus lies on palliation of symptoms, which is not necessarily a resection of the primary tumor. Both situations motivate adequate staging before treatment in CRC. This prospective observational study evaluates the outcomes after the introduction of routine staging with abdominal CT before treatment.</p> <p>Methods</p> <p>In a prospective observational study of 612 consecutive patients (2007-2009), the ability of abdominal CT to find liver metastases (LM), peritoneal carcinomatosis (PC) and T4 stage in colon cancer (CC) was analysed.</p> <p>Results</p> <p>Advanced CRC was present in 58% of patients, mCRC in 31%. The ability to find LM was excellent (99%), cT4 stage CC good (86%) and PC poor (33%). In the group of surgical patients with emergency presentations, the incidences of both mCRC (51%) and locally advanced colon cancer (LACC) (69%) were higher than in the elective group (20% and 26% respectively). Staging tended to be omitted more often in the emergency group (35% versus 12% in elective surgery).</p> <p>Conclusions</p> <p>The strengths of staging with abdominal CT are to find LM and LACC, however it fails in diagnosing PC. On grounds of the incidence of advanced CRC, staging is warranted in patients with emergency presentations as well.</p

Predictors of early recurrence after resection of colorectal liver metastases

BACKGROUND: Early recurrence after resection of colorectal liver metastases (CLM) is common. Patients at risk of early recurrence may be candidates for enhanced preoperative staging and/or earlier postoperative imaging. The aim of this study was to determine if there are any risk factors that specifically predict early liver-only and systemic recurrence. METHODS: Retrospective analysis of prospective database of patients undergoing liver resection (LR) for CLM from 2004 to 2006 was undertaken. Early recurrence was defined as occurring within 18 months of LR. Patients were classified into three groups: early liver-only recurrence, early systemic recurrence and recurrence-free. Preoperative factors were compared between patients with and without early recurrence. RESULTS: Two hundred and forty-three consecutive patients underwent LR for CLM. Twenty-seven patients (11%) developed early liver-only recurrence. Dukes C stage and male sex were significantly associated with early liver-only recurrence (P < 0.05). Sixty-six patients (27%) developed early systemic recurrence. Tumour size ≥3.6 cm and tumour number (>2) were significantly associated with early systemic recurrence (P < 0.001). CONCLUSIONS: It is possible to stratify patients according to the risk of early liver-only or systemic recurrence after resection of CLM. High-risk patients may be candidates for preoperative MRI and/or computed tomography-positron emission tomography (CT-PET) scan and should receive intensive postoperative surveillance

Contemporary Management of Locally Advanced and Recurrent Rectal Cancer: Views from the PelvEx Collaborative

Pelvic exenteration is a complex operation performed for locally advanced and recurrent pelvic cancers. The goal of surgery is to achieve clear margins, therefore identifying adjacent or involved organs, bone, muscle, nerves and/or vascular structures that may need resection. While these extensive resections are potentially curative, they can be associated with substantial morbidity. Recently, there has been a move to centralize care to specialized units, as this facilitates better multi-disciplinary care input. Advancements in pelvic oncology and surgical innovation have redefined the boundaries of pelvic exenterative surgery. Combined with improved neoadjuvant therapies, advances in diagnostics, and better reconstructive techniques have provided quicker recovery and better quality of life outcomes, with improved survival This article provides highlights of the current management of advanced pelvic cancers in terms of surgical strategy and potential future developments