Energy Efficient and Reliable Wireless Sensor Networks - An Extension to IEEE 802.15.4e

Collecting sensor data in industrial environments from up to some tenth of battery powered sensor nodes with sampling rates up to 100Hz requires energy aware protocols, which avoid collisions and long listening phases. The IEEE 802.15.4 standard focuses on energy aware wireless sensor networks (WSNs) and the Task Group 4e has published an amendment to fulfill up to 100 sensor value transmissions per second per sensor node (Low Latency Deterministic Network (LLDN) mode) to satisfy demands of factory automation. To improve the reliability of the data collection in the star topology of the LLDN mode, we propose a relay strategy, which can be performed within the LLDN schedule. Furthermore we propose an extension of the star topology to collect data from two-hop sensor nodes. The proposed Retransmission Mode enables power savings in the sensor node of more than 33%, while reducing the packet loss by up to 50%. To reach this performance, an optimum spatial distribution is necessary, which is discussed in detail

Noncovalent interactions of drugs with immune receptors may mediate drug-induced hypersensitivity reactions

Drug-induced hypersensitivity reactions are instructive examples of immune reactions against low molecular weight compounds. Classically, such reactions have been explained by the hapten concept, according to which the small antigen covalently modifies an endogenous protein; recent studies show strong associations of several HLA molecules with hypersensitivity. In recent years, however, evidence has become stronger that not all drugs need to bind covalently to the major histocompatibility complex (MHC)-peptide complex in order to trigger an immune response. Rather, some drugs may bind reversibly to the MHC or possibly to the T-cell receptor (TCR), eliciting immune reactions akin to the pharmacological activation of other receptors. While the exact mechanism is still a matter of debate, noncovalent drug presentation clearly leads to the activation of drug-specific T cells. In some patients with hypersensitivity, such a response may occur within hours of even the first exposure to the drug. Thus, the reaction to the drug may not be the result of a classical, primary response but rather be mediated by existing, preactivated T cells that display cross-reactivity for the drug and have additional (peptide) specificity as well. In this way, certain drugs may circumvent the checkpoints for immune activation imposed by the classical antigen processing and presentation mechanisms, which may help to explain the idiosyncratic nature of many drug hypersensitivity reaction

T cell receptor variable β20-1 harbors a nucleotide binding pocket in the CDR2β loop.

Novel aspects of T cells containing TCRVβ20-1 are numerous, ranging from pathogen specific reactivity to specific tissue homing, or possible T cell subsets. Recently, it was demonstrated that TCR itself could become reactive by binding to small molecules free of the pHLA interface. Our work here was to identify a natural ligand binding to an identified pocket on the CDR2β loop of these TCR. Using docking of suspected ligands, we were able to show Guanine and Adenine di- and tri-nucleotides readily bind to the identified site. Comparing these with small molecule sites found on other TCR types, we show this interaction is novel. With further molecular dynamic simulations, these sites are shown to be plausible by conducting simple computational based solubility tests as cross validation. Combined with simple proliferative responses, the identified nucleotides are also shown to have functional consequences by inducing T cell proliferation for CD4/Vβ20-1 + T cells, while failing to induce proliferation in other T cell isolates. Merging computational and simple cell assays, this work establishes a role of nucleotides in T cells found to contain this TCR sub-type

Compte rendu de:Robert M. Kerr 2010, " Some thoughts on the origins of the Libyco-Berber Alphabet. " Études berbères V. Actes du "Bayreuth - Frankfurt - Leidener Kolloquim zur Berberologie". Köln : 41 - 68.

International audienceCompte rendu de:Robert M. Kerr 2010, " Some thoughts on the origins of the Libyco-Berber Alphabet. " Études berbères V. Actes du "Bayreuth - Frankfurt - Leidener Kolloquim zur Berberologie". Köln : 41 - 68

Analyzing coarsened categorical data with or without probabilistic information

In some applications, only a coarsened version of a categorical outcome variable can be observed. Parametric inference based on the maximum likelihood approach is feasible in principle, but it cannot be covered computationally by standard software tools. In this article, we present two commands facilitating maximum likelihood estimation in this situation for a wide range of parametric models for categorical outcomes-in the cases both of a nominal and an ordinal scale. In particular, the case of probabilistic information about the possible values of the outcome variable is also covered. Two examples motivating this scenario are presented and analyzed

The role of drug, dose and the tolerance/intolerance of new drugs in multiple drug hypersensitivity syndrome (MDH).

BACKGROUND Multiple drug hypersensitivity syndrome (MDH) is used to describe persons with a drug hypersensitivity reaction (DHR) to at least two chemically unrelated drugs, confirmed by skin test or in vitro assay. METHODS Medical records of 25 patients with MDH, tested and confirmed at our allergy division were retrospectively evaluated in terms of clinical course, involved drugs, daily drug dose, latency periods, test results of skin test and cellular assays and tolerated drugs in subsequent pharmacological treatments. RESULTS MDH almost exclusively appeared as a delayed, often severe DHR and started in 14/25 with a drug reaction with eosinophilia and systemic symptoms (DRESS). Penicillins (13/25, 52.0%) and cephalosporins (6/25, 24.0%), typical high dose drugs, were most often identified as elicitors of MDH, especially at the first DHR, followed by aromatic antiepileptics (7/25, 28.0%), vancomycin (4/25, 16.0%) and antibiotic sulfonamides (4/25, 16.0%). Cephalosporins, clindamycine and radio contrast media (RCM) were mainly involved in subsequent DHR. The median daily drug dose of all drug trigger was 1875.0 mg (662.5; 2100.0) at the first DHR and 600.0 mg (300.0; 1300.0) at subsequent DHR, p=0.0420. CONCLUSION High dose drugs, especially betalactam antibiotics, RCM and clindamycin are common elicitors of subsequent DHR in patients with MDH. Macrolides, quinolones, doxycycline, non-aromatic antiepileptics and paracetamol were often tolerated. As the same drugs elicited both flare-up reactions and real DHR, drug induced flare-up reactions may be precursors of a possible second DHR and MDH. The administration of highly dosed drugs should be avoided in patients at risk for MDH

Age-at-death estimation in archaeological samples: Differences in population means resulting from different aging methods can be predicted from the mean ages of method-specific reference samples

Age mimicry is a well-known phenomenon in the application of osteological age-estimation methods. Age mimicry refers to the fact that predicting age-at-death from a specific trait (age indicator) based on the relation observed in a specific reference sample implies that age estimates to some degree reflect the age structure of the reference sample. In particular, the estimated population mean in a target population in which an age-estimation method is applied is shifted towards the mean in the method-specific reference sample. Consequently, differences in population means between different age-estimation methods in the same target population may be due to differences in mean age of the reference samples used to develop the age-estimation methods. We aim at quantifying the expected magnitude for such differences. Fifteen different traditional age-estimation methods were applied to a sample of 675 adult individuals from the early medieval cemetery of Mannheim-Seckenheim. The relation of the observed estimated population age means and the mean age in the reference samples was analyzed by linear regression. We find that up to 80% of the variation in the estimated population age means can be explained by the variation of the mean age in the reference samples. Furthermore, differences in the magnitude of 3 to 4 years in the mean age between two reference samples can imply a 1-year difference in estimated target population age means. Because large differences in mean age between reference samples used to develop different age-estimation methods are common, some care is needed in interpreting differences between individual age estimates or population mean age estimates in cases where different age-estimation techniques are used

Sequential appearance of four clinical delayed drug hypersensitivity in the same patient

This patient had a two-month history of four clinical manifestations of drug hypersensitivity reactions (DHR): maculo papular eruption, Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS), acute generalized exanthematous pustulosis (AGEP) and toxic epidermal necrolysis (TEN). The eliciting drugs were rifampicin, possibly gabapentin, levofloxacin, meropenam and/or colistin. Thus, the patient might develop a multiple drug hypersensitivity syndrome. The TEN-like lesion appeared after stopping drugs for two days. A different manifestation of DHR in dependence of drug use suggests that the distinct manifestations of DHRs are due to the stimulation of T cells with distinct functions. The simultaneous appearance of AGEP and DRESS symptoms might be due to the simultaneous stimulation of two (or more) different T cell subsets, which are functionally dominant. Lastly, the appearance and further propagation of symptoms after therapy-stop is a common but somewhat neglected problem in DHR, which raises questions regarding the cause of persisting T cell activation

A world allergy organization international survey on diagnostic procedures and therapies in drug allergy/hypersensitivity.

RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are.OBJECTIVE: To study the diagnostic and treatment modalities used in drug allergy/hypersensitivity among members of the World Allergy Organization (WAO). METHODS: A questionnaire comprising 39 questions was circulated electronically to member societies, associate member societies, and regional and affiliate organizations of WAO between June 29, 2009, and August 9, 2009. RESULTS: Eighty-two responses were received. Skin testing was used by 74.7%, with only 71.4% having access to penicillin skin test reagents. In vitro-specific IgE tests were used by 67.4%, and basophil activation test was used by 54.4%. Lymphocyte transformation tests were used by 36.8% and patch tests by 54.7%. Drug provocation tests were used by 68.4%, the most common indication being to exclude hypersensitivity where history/symptoms were not suggestive of drug hypersensitivity/allergy (76.9%). Rapid desensitization for chemotherapy, antibiotics, or biologic agents was used by 69.6%. Systemic corticosteroid was used in the treatment of Stevens-Johnson syndrome by 72.3%, and high-dose intravenous immunoglobulins in toxic epidermal necrolysis by 50.8%. Human leukocyte antigen screening before prescription of abacavir was used by 92.9% and before prescription of carbamazepine by 21.4%. CONCLUSIONS: Results of this survey form a useful framework for developing educational and training needs and for improving access to drug allergy diagnostic and treatment modalities across WAO member societies