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Energy harvesting network (EHN) is a trending topic in wireless communications that enables wireless devices to harvest energy from ambient sources such as RF waves. However, EHN faces energy causality constraint that turns the energy harvester into sleep mode. This, in turn, delays the processing of next task until harvesting the required energy for processing. The objective of this research is to prolong the active mode of energy harvesters by employing a novel scheme of EHN that combines local computing and wireless distributed computing in one EHN. Accordingly, a novel EHN algorithm that employs partially observable Markov decision process (POMDP) is proposed in order to automate the decision of the energy harvester based on the channel variations and stored energy. Herein, the scheme of the proposed EHN is explained first. Then, the problem of the proposed EHN is formulated as POMDP. Furthermore, a policy is found in order to estimate the validity of the proposed EHN against the conventional EHN.

Purpose Interventional radiology (IR) has historically failed to fully capture the value of evaluation and management services in the inpatient setting. Understanding financial benefits of a formally incorporated billing discipline may yield meaningful insights for interventional practices. Materials and Methods A revenue modeling tool was created deploying standard financial modeling techniques, including sensitivity and scenario analyses. Sensitivity analysis calculates revenue fluctuation related to dynamic adjustment of discrete variables. In scenario analysis, possible future scenarios as well as revenue potential of different-size clinical practices are modeled. Results Assuming a hypothetical inpatient IR consultation service with a daily patient census of 35 patients and two new consults per day, the model estimates annual charges of $2.3 million and collected revenue of $390,000. Revenues are most sensitive to provider billing documentation rates and patient volume. A range of realistic scenarios—from cautious to optimistic—results in a range of annual charges of $1.8 million to $2.7 million and a collected revenue range of $241,000 to $601,000. Even a small practice with a daily patient census of 5 and 0.20 new consults per day may expect annual charges of $320,000 and collected revenue of $55,000. Conclusions A financial revenue modeling tool is a powerful adjunct in understanding economics of an inpatient IR consultation service. Sensitivity and scenario analyses demonstrate a wide range of revenue potential and uncover levers for financial optimization.

Road construction on sabkha terrain along the coastal regions of the Arabian Gulf and the Red Sea is often faced with different types of damage due to the low bearing capacity of sabkha deposits, especially when they are wetted. Such conditions necessitate the improvement of sabkha prior to any construction. The purpose of this investigation was to upgrade the load-carrying capacity of sabkha soil using geotextiles by varying the geotextile type, base thickness, moisture condition and the magnitude of the deviatoric stress. To achieve these objectives, a special mould was fabricated to accommodate the soil-fabric-aggregate (SFA) systems. The performance of SFA systems was evaluated by measuring the permanent deformation under the applied ‘dynamic’ load. Results of this study indicate that the selection of an appropriate geotextile type can bring about significant improvement in the load-carrying capacity of the water-sensitive sabkha soils, particularly under soaked conditions. The inclusion of a geotextile layer on top of the sabkha subgrade reduced the thickness of the graded base layer by 34%. In addition, the geotextile increased the stiffness of the sabkha subgrade and reduced the permanent deformation after a certain number of load reputations.

Studies on precocious puberty have primarily focused on children with typical patterns of growth and cognitive development. This study reviewed diagnostic data from the records of 15,719 patients with neurodevelopmental disabilities for diagnoses associated with premature sexual development/precocious puberty. Thirty-two individuals with premature sexual development were identified, with the earliest changes seen in one girl at 1 year 7 months of age. In this group, the mean age at onset was 7 years 2 months in boys and 5 years 11 months in girls. Central precocious puberty, which was the most common cause of onset of early pubertal changes, was present in 15 of the 32 children. The results of this study suggest that children with a neurodevelopmental disability are at increased risk of premature pubertal changes when compared to children without a neurodevelopmental disability. This study indicates the need for health-care providers to be vigilant in screening for early pubertal changes in children with neurodevelopmental disabilities.

The paper presents families of quadriphase sequences derived from maximal length sequences over {\bf Z}_4 having good correlation properties. These are: (i) families of quadriphase sequences of period (2^r-1) from maximal length sequences over {\bf Z}_4 ; each family consisting of (2^r+1) sequences, (ii) families of quadriphase sequences of period 2(2^r-1) from interleaved maximal length sequences over {\bf Z}_4 ; each family consisting of (2^{r-1}+1) sequences. Such sequences are of interest in quadriphase modulated code division multiple access communication systems, where it is desirable to have large sets of sequences that possess low value of \theta _\max } , the maximum magnitude of the periodic crosscorrelation and out of phase auto-correlation values. The sequences over {\bf Z}_4 are viewed as trace functions of appropriately chosen unit elements of Galois extension rings of {\bf Z}_4 . Quadriphase sequences are then obtained from {\bf Z}_4 sequences, by a quadriphase mapping, \Pi , from {\bf Z}_4 to 4^th roots of unity, given by, \Pi (x) = \omega ^x ; where x \in {\bf Z}_4 and \omega = \sqrt-1 . Periodic correlation properties (correlation values and their distribution) of the quadriphase sequences are obtained by using an Abelian association scheme on the elements of the corresponding Galois extension ring of {\bf Z}_4 . The majority of the families of sequences derived are optimal with respect to the Welch lower bound on \theta _\max ; the rest being suboptimal with \theta _\max bounded by \sqrt2L , where L is the period\newpage of the sequences. However nearly half of the sequences in these families are balanced.

Interpreting sets of cyclic and dyadic shifts as specific examples of transitive abelian permutation groups, it is shown that every such group defines a class of permutation-invariant systems, which have structural properties analogous to those of the so-called cyclic and dyadic convolution systems, and which are likely to have similar applications in the filtering of finite discrete data.

Isolated central nervous system (CNS) mucormycosis is a rare but life-threatening infection. We report a case of bilateral frontal lobe mucormycosis in a previously healthy woman. Intravenous drug use was the most likely route of infection. After treatment with surgical drainage and amphotericin B, she survived but suffered permanent neurologic deficits. We identified 29 previous reports of isolated CNS mucormycosis in the medical literature. Including our case, the patients averaged 32 years of age and most were male. Intravenous drug use appears to be the most important risk factor, present in 20 patients (67%). Treatment with amphotericin B was the only predictor of survival, reducing mortality from 92% to 41%. Isolated CNS mucormycosis should be considered in the differential diagnosis of brain abscesses, especially in intravenous drug users. Prompt initiation of therapy with amphotericin B may be life-saving.

Foamed asphalt technology has increasingly gained acceptance as an effective and economical soil improvement and stabilization technique, mainly because of its improved aggregate penetration, coating capabilities, and handling and compaction characteristics. This laboratory research program was carried out to investigate the feasible use of foamed asphalt technology in Saudi Arabia to improve the prevalent dune sands for possible use as a base or subbase material. Several variables were investigated to evaluate the relative improvement of dune sand as well as to permit the development of design procedures for the future use of foamed asphalt technology in the harsh climatic conditions of eastern Saudi Arabia. Statistical analysis of the results was employed to verify the effects of emulsified asphalt and foamed asphalt treatment, with and without the addition of Portland cement, on the strength characteristics of the treated mixes. The results displayed significant improvement in the performance of dune sand foamed asphalt mixes, as compared to that of the emulsified asphalt mixes.

The problem of maximizing SNR at the output of a cyclic convolution system is considered. It is shown that the required impulse response function of the system has an interpretation analogous to that of matched filter. Similarities and differences with the matched filter are discussed.