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Polysaccharides can be elite carriers for therapeutic molecules due to their versatility and low probability to trigger toxicity and immunogenic responses. Local and systemic therapies can be achieved through particle pulmonary delivery, a promising non-invasive alternative. Successful pulmonary delivery requires particles with appropriate flowability to reach alveoli and avoid premature clearance mechanisms. Polysaccharides can form micro-, nano-in-micro-, and large porous particles, aerogels, and hydrogels. Herein, the characteristics of polysaccharides used in drug formulations for pulmonary delivery are reviewed, providing insights into structure-function relationships. Charged polysaccharides can confer mucoadhesion, whereas the ability for specific sugar recognition may confer targeting capacity for alveolar macrophages. The method of particle preparation must be chosen considering the properties of the components and the delivery device to be utilized. The fate of polysaccharide-based carriers is dependent on enzyme-triggered hydrolytic and/or oxidative mechanisms, allowing their complete degradation and elimination through urine or reutilization of released monosaccharides.

Longan (Dimocarpus longan Lour.) is a seasonal tropical fruit used by Chinese medicine in both fresh and dried pulp forms. Their polysaccharides have been reported to have biological activity. However, their composition and immune activity have not yet been disclosed. To fulfil this aim, hot water-soluble polysaccharides of fresh and dried longan pulp were fractionated according to their molecular weight by ultrafiltration (10, 50, 100 kDa cut off). The main polysaccharides recovered were 1,6-linked glucans branched at O-3 (4–8%), O-2 (1%), O-2,4 (0.1%), and O-3,4 (0.1%). The drying process promotes the solubility of the polysaccharides. These glucans from fresh and dried longan pulp have immunomodulatory activity, shown by in vitro phagocytosis, NO, TNF-α, and IL-6 macrophages production assays. They showed also to inhibit the inflammatory response induced by LPS. The immunological activity of these glucans seems to have different responses dependent on their molecular weight, related to the immune regulatory pathways.

The diagnosis of cerebral vein thrombosis (CVT) can be difficult. Patients with suspected CVT, in whom venous sinuses are affected by intracranial tumours or after intracranial surgery constitutes a particular challenging setting. Magnetic resonance non-contrast thrombus imaging (MR-NCTI) is a new magnetic resonance imaging (MRI) technique that has previously been shown to be accurate in the diagnosis of a first CVT and difficult-to-diagnose venous thrombosis in other anatomical locations. In this case report, a patient with a medical history of craniotomy for parieto-occipital meningioma was suspected of an acute CVT, but had an inconclusive computed tomography (CT) and MRI venography. MR-NCTI showed no abnormalities diagnostic for (sub)acute CVT and thus cerebral sinus occlusion was most likely a chronic thrombus or a result of residual meningioma tissue. Anticoagulant treatment was discontinued and she was discharged from hospital in good health. This case shows that MR-NCTI may be a valuable additional imaging test in complex cases in whom CT and MRI venography could not exclude acute CVT.

Single-dose coffee capsule system is a technology used to prepare espresso coffee which offers consumers the possibility to choose among several blends. However, the characterization of espresso coffees extracted with these systems, namely regarding polysaccharides structures and melanoidin content, is scarce. In order to define a carbohydrate and melanoidin composition pattern for single-dose espresso coffee base blends, a range of 6 commercial espresso coffee blends was studied. In addition, a decaffeinated blend and a blend supplemented with plant natural extracts were also included. The base blends showed galactomannans as the predominant polysaccharides over arabinogalactans, on the contrary of the decaffeinated blend. The blend supplemented with natural plant extracts showed glucose-rich polysaccharides. The labelled intensity of coffee single-dose seems to be related with the unknown brown compounds of melanoidins, present in the high molecular weight material of the brews. A pattern could be obtained for single-dose espresso coffee base blends, presenting an average per cup of 1.21 g of total solids and 242 mg of soluble dietary fibre, constituted by 62 mg of galactomannans and 48 mg of arabinogalactans, and 123 mg of melanoidins. On average, 46% of espresso coffee low molecular weight compounds are adsorbed to the high molecular weight material, evidencing the importance of the adsorption/desorption phenomena for the properties of coffee dietary fibre.

Local area wireless networks are like cellular systems: Stations associate to one out of several access points (APs), which connect to a wired backbone. Due to signal attenuation and transmission power limitations, radio connectivity is available only sufficiently close to an AP. In scenarios with a dense deployment of APs the wired backbone causes unprofitably high costs. A Wireless Mesh Network (WMN) serves to extend the coverage of APs by means of Mesh Points (MPs) that forward data between a station and an AP. This concept reduces deployment costs, but reduces also network capacity, owing to multiple transmissions of the same data packet on its multi-hop route. This paper analyzes how the capacity of cost-limited WMNs can be optimized. A layered model of a WMN specifying the typical characteristics of the network is used to calculate the upper capacity bound. Based on the heuristics developed, networks of more than 150 nodes (APs, MPs and stations) can be handled. We apply the method to investigate the combination of three measures for improving the WMN capacity: (i) concurrent scheduling of transmissions, (ii) application of directional antennas and (iii) variable number of MPs per AP. The capacity bounds for different combinations of the measures mentioned is computed and compared. Combined with a simple cost model, these results are useful to provide insight into the economical feasibility of WMNs for wireless Internet access.

The main part of the code presented in this work represents an implementation of the split-operator method [J.A. Fleck, J.R. Morris, M.D. Feit, Appl. Phys. 10 (1976) 129–160; R. Heather, Comput. Phys. Comm. 63 (1991) 446] for calculating the time-evolution of Dirac wave functions. It allows to study the dynamics of electronic Dirac wave packets under the influence of any number of laser pulses and its interaction with any number of charged ion potentials. The initial wave function can be either a free Gaussian wave packet or an arbitrary discretized spinor function that is loaded from a file provided by the user. The latter option includes Dirac bound state wave functions. The code itself contains the necessary tools for constructing such wave functions for a single-electron ion. With the help of self-adaptive numerical grids, we are able to study the electron dynamics for various problems in 2+1 dimensions at high spatial and temporal resolutions that are otherwise unachievable. Along with the position and momentum space probability density distributions, various physical observables, such as the expectation values of position and momentum, can be recorded in a time-dependent way. The electromagnetic spectrum that is emitted by the evolving particle can also be calculated with this code. Finally, for planning and comparison purposes, both the time-evolution and the emission spectrum can also be treated in an entirely classical relativistic way. Besides the implementation of the above-mentioned algorithms, the program also contains a large C++ class library to model the geometric algebra representation of spinors that we use for representing the Dirac wave function. This is why the code is called “Dirac++”. Program summary Program title: Dirac++ or (abbreviated) d++ Catalogue identifier: AEAS_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEAS_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 474 937 No. of bytes in distributed program, including test data, etc.: 4 128 347 Distribution format: tar.gz Programming language: C++ Computer: Any, but SMP systems are preferred Operating system: Linux and MacOS X are actively supported by the current version. Earlier versions were also tested successfully on IRIX and AIX Number of processors used: Generally unlimited, but best scaling with 2–4 processors for typical problems RAM: 160 Megabytes minimum for the examples given here Classification: 2.7 External routines: FFTW Library [3,4], Gnu Scientific Library [5], bzip2, bunzip2 Nature of problem: The relativistic time evolution of wave functions according to the Dirac equation is a challenging numerical task. Especially for an electron in the presence of high intensity laser beams and/or highly charged ions, this type of problem is of considerable interest to atomic physicists. Solution method: The code employs the split-operator method [1,2], combined with fast Fourier transforms (FFT) for calculating any occurring spatial derivatives, to solve the given problem. An autocorrelation spectral method [6] is provided to generate a bound state for use as the initial wave function of further dynamical studies. Restrictions: The code in its current form is restricted to problems in two spatial dimensions. Otherwise it is only limited by CPU time and memory that one can afford to spend on a particular problem. Unusual features: The code features dynamically adapting position and momentum space grids to keep execution time and memory requirements as small as possible. It employs an object-oriented approach, and it relies on a Clifford algebra class library to represent the mathematical objects of the Dirac formalism which we employ. Besides that it includes a feature (typically called “checkpointing”) which allows the resumption of an interrupted calculation. Additional comments: Along with the program's source code, we provide several sample configuration files, a pre-calculated bound state wave function, and template files for the analysis of the results with both MatLab and Igor Pro. Running time: Running time ranges from a few minutes for simple tests up to several days, even weeks for real-world physical problems that require very large grids or very small time steps. References: [1] J.A. Fleck, J.R. Morris, M.D. Feit, Time-dependent propagation of high energy laser beams through the atmosphere, Appl. Phys. 10 (1976) 129–160. [2] R. Heather, An asymptotic wavefunction splitting procedure for propagating spatially extended wavefunctions: Application to intense field photodissociation of H + 2 , Comput. Phys. Comm. 63 (1991) 446. [3] M. Frigo, S.G. Johnson, FFTW: An adaptive software architecture for the FFT, in: Proceedings of the IEEE International Conference on Acoustics, Speech and Signal Processing, vol. 3, IEEE, 1998, pp. 1381–1384. [4] M. Frigo, S.G. Johnson, The design and implementation of FFTW3, in: Proceedings of the IEEE, vol. 93, IEEE, 2005, pp. 216–231. URL: http://www.fftw.org/ . [5] M. Galassi, J. Davies, J. Theiler, B. Gough, G. Jungman, M. Booth, F. Rossi, GNU Scientific Library Reference Manual, second ed., Network Theory Limited, 2006. URL: http://www.gnu.org/software/gsl/ . [6] M.D. Feit, J.A. Fleck, A. Steiger, Solution of the Schrodinger equation by a spectral method, J. Comput. Phys. 47 (1982) 412–433.

This article presents a combined layer two and three control loop, which allows prediction of link breakage in wireless ad hoc networks. The method monitors the physical layer transmission mode on layer two and exploits the gained knowledge at layer three. The mechanism bases on link adaptation, which is used in IEEE 802.11a WLAN to select the transmission mode according to the link quality. The process of link adaptation contains information that is useful to predict link stability and link lifetime. After introducing the IEEE 802.11a Medium Access Control (MAC) and PHY layer, we present insight to the IEEE 802.11a link adaptation behaviour in multi-hop ad hoc networks. The link adaptation algorithm presented here is derived from Auto Rate Fallback (ARF) algorithm. We survey the performance gain of two newly developed route adaptation approaches exploding the prediction results. One approach is Early Route ReArrangement (ERRA) that starts a route reconstruction procedure before link breakage. Hence, an alternative route is available before connectivity is lost. Early Route Update (ERU) is a complementing approach that enhances this process, by communications among routing nodes surrounding the breaking link. The delay caused by route reconstruction can be significantly reduced if prediction and either of our new route discovery processes is used.

With current amendments, transmission rates of 100Mb/s and more become possible with IEEE 802.11 WLANs. On the one hand, this allows the end user to change from wired to wireless infrastructure in even more application scenarios; on the other hand interference sensitive modes reduce the maximum range between the mobile station and the access point (AP). To extend the transmission range transparently, relay APs form a mesh network and provide wireless connection over large areas. Besides path selection, a crucial capability of a wireless mesh network is the ability to share the available spectrum among the participants. In this work, we classify two inherently different MAC protocols according to this ability. The well-known IEEE 802.11 DCF takes the position of a typical CSMA/CA protocol, whereas the Mesh Network Alliance (MNA) represents a distributed, reservation-based approach. To assess their performance, we follow a dual approach: first we develop a method to compute the capacity bounds of the protocols in the considered scenarios. It helps to estimate the absolute gain of spectrum sharing in wireless mesh networks. Second, the WARP2 simulation engine is used to compare the distributed behaviour of both protocols. This results in a relative evaluation. A final conclusion is drawn by combining the simulation and the theoretical results. It underlines the significant possibilities of the MNA approach and shows future directions for capacity gains.

A new implementation of the split-operator method for calculating the time-evolution of Dirac wave functions is presented. With the help of self-adaptive numerical grids we are able to study the dynamics of an initially free electronic Dirac wave packet under the influence of an ultra-intense laser pulse and its scattering at a highly charged ion. Furthermore, we provide the necessary tools for constructing the Dirac ground state wave function of any single-electron ion and demonstrate them for hydrogenic oxygen. Bound Dirac dynamics in a super-strong laser field is finally investigated.

The word “autopsy” was derived from the Greek autopsia, meaning “to see with one's eyes.” Throughout most of history, autopsy findings were limited to what could be deduced from the evidence available to the naked eye. Today, x-ray and medical technology augment the pathologist's eyes, allowing more than just visual examination of bodies. Autopsy is the gold standard for ascertaining cause of death in American medicine, serving to confirm pathology, clinical diagnoses, and the appropriateness of pre-death treatments. Autopsy findings wind their way to practicing pharmacists via circuitous routes. Researchers and toxicologists use autopsy findings to monitor how drugs really work over the short and long terms. Regulators and legislators connect autopsy findings with police reports, medication error reports, and case reports to develop new labeling or implement stricter laws. Medical chemists use the same findings to seek new and better drugs. Language: en