Joint practice guidelines for radionuclide lymphoscintigraphy for sentinel node localization in oral/oropharyngeal squamous cell carcinoma

Involvement of the cervical lymph nodes is the most important prognostic factor for patients with oral/oropharyngeal squamous cell carcinoma (OSCC), and the decision whether to electively treat patients with clinically negative necks remains a controversial topic. Sentinel node biopsy (SNB) provides a minimally invasive method of determining the disease status of the cervical node basin, without the need for a formal neck dissection. This technique potentially improves the accuracy of histological nodal staging and avoids over-treating three-quarters of this patient population, minimizing associated morbidity. The technique has been validated for patients with OSCC, and larger-scale studies are in progress to determine its exact role in the management of this patient population. This article was designed to outline the current best practice guidelines for the provision of SNB in patients with early-stage OSCC, and to provide a framework for the currently evolving recommendations for its use. These guidelines were prepared by a multidisciplinary surgical/nuclear medicine/pathology expert panel under the joint auspices of the European Association of Nuclear Medicine (EANM) Oncology Committee and the Sentinel European Node Trial Committee

Contrasting resource allocation patterns in Sedum lanceolatum Torr.: Biomass versus energy estimates

Biomass determinations and microbomb calorimetry were used to assess resource allocation in Sedum lanceolatum Torr. between 2,257 and 3,726 m above sea level in the Front Range of the Rocky Mountains, Colorado, USA. In general, energy values did not differ within a tissue among sites, but did differ among tissue types. Flowers and leaves had the greatest energy content per gram ashfree dry weight. Total kilojoules per plant were homogeneous along the elevational gradient.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47753/1/442_2004_Article_BF00379785.pd

Communal roosting sites are potential ecological traps: experimental evidence in a Neotropical harvestman

Situations in which animals preferentially settle in low-quality habitat are referred to as ecological traps, and species that aggregate in response to conspecific cues, such as scentmarks, that persist after the animals leave the areamay be especially vulnerable. We tested this hypothesis on harvestmen (Prionostemma sp.) that roost communally in the rainforest understory. Based on evidence that these animals preferentially settle in sites marked with conspecific scent, we predicted that established aggregation sites would continue to attract new recruits even if the animals roosting there perished. To test this prediction, we simulated intense predation by repeatedly removing all individuals from 10 established roosts, and indeed, these sites continued to attract new harvestmen. A more likely reason for an established roost to become unsuitable is a loss of overstory canopy cover caused by treefalls. To investigate this scenario, without felling trees, we established 16 new communal roosts by translocating harvestmen into previously unused sites. Half the release sites were located in intact forest, and half were located in treefall gaps, but canopy cover had no significant effect on the recruitment rate. These results support the inference that communal roost sites are potential ecological traps for species that aggregate in response to conspecific scent

Spectral characterization of analog samples in anticipation of OSIRIS-REx's arrival at Bennu: A blind test study

We present spectral measurements of a suite of mineral mixtures and meteorites that are possible analogs for asteroid (101955) Bennu, the target asteroid for NASA's Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx) mission. The sample suite, which includes anhydrous and hydrated mineral mixtures and a suite of chondritic meteorites (CM, CI, CV, CR, and L5), was chosen to characterize the spectral effects due to varying amounts of aqueous alteration and minor amounts of organic material. Our results demonstrate the utility of mineral mixtures for understanding the mixing behavior of meteoritic materials and identifying spectrally dominant species across the visible to near-infrared (VNIR) and thermal infrared (TIR) spectral ranges. Our measurements demonstrate that, even with subtle signatures in the spectra of chondritic meteorites, we can identify diagnostic features related to the minerals comprising each of the samples. Also, the complementary nature of the two spectral ranges regarding their ability to detect different mixture and meteorite components can be used to characterize analog sample compositions better. However, we observe differences in the VNIR and TIR spectra between the mineral mixtures and the meteorites. These differences likely result from (1) differences in the types and physical disposition of constituents in the mixtures versus in meteorites, (2) missing phases observed in meteorites that we did not add to the mixtures, and (3) albedo differences among the samples. In addition to the initial characterization of the analog samples, we will use these spectral measurements to test phase detection and abundance determination algorithms in anticipation of mapping Bennu's surface properties and selecting a sampling site

CT radiation dose in children: a survey to establish age-based diagnostic reference levels in Switzerland

This work aimed at assessing the doses delivered in Switzerland to paediatric patients during computed tomography (CT) examinations of the brain, chest and abdomen, and at establishing diagnostic reference levels (DRLs) for various age groups. Forms were sent to the ten centres performing CT on children, addressing the demographics, the indication and the scanning parameters: number of series, kilovoltage, tube current, rotation time, reconstruction slice thickness and pitch, volume CT dose index (CTDI(vol)) and dose length product (DLP). Per age group, the proposed DRLs for brain, chest and abdomen are, respectively, in terms of CTDI(vol): 20, 30, 40, 60 mGy; 5, 8, 10, 12 mGy; 7, 9, 13, 16 mGy; and in terms of DLP: 270, 420, 560, 1,000 mGy cm; 110, 200, 220, 460 mGy cm; 130, 300, 380, 500 mGy cm. An optimisation process should be initiated to reduce the spread in dose recorded in this study. A major element of this process should be the use of DRLs