Mental compression of spatial sequences in human working memory using numerical and geometrical primitives

How does the human brain store sequences of spatial locations? The standard view is that each consecutive item occupies a distinct slot in working memory. Here, we formulate and test the alternative hypothesis that the human brain compresses the whole sequence using an abstract, language-like code that captures the numerical and geometrical regularities of the sequence at multiple nested levels. We exposed participants to spatial sequences of fixed length but variable regularity, and asked them to remember the sequence in order to detect deviants, while their brain activity was recorded using magneto-encephalography. Using multivariate decoders, each successive location could be decoded from brain signals, and upcoming locations were anticipated prior to their actual onset. Crucially, sequences with lower complexity, defined as the minimal description length provided by the formal language, and whose memory representation was therefore predicted to be more compressed, led to lower error rates and to increased anticipations. Furthermore, neural codes specific to the numerical and geometrical primitives of the postulated language could be detected, both in isolation and within the sequences. These results suggest that the human brain detects sequence regularities at multiple nested levels and uses them to compress long sequences in working memory.

Wideband Cognitive Radio based on Scheduled Sequential Compressed Spectrum Sensing

The cooperation for big data applications through the cognitive radio innovation requires wideband spectrum sensing. Conversely, it is expensive to employ long haul wideband detecting and is particularly troublesome within the sight of vulnerability. For example, more noise, obstruction, anomalies, as well as channel blurring. In this article, we project the planning of successive compacted range detecting which together endeavors compressive sensing (CS) and consecutive occasional identification procedures to accomplish increasingly exact and convenient wideband detecting. Rather than summoning CS to recreate the signal in every period, our projected plan executes in reverse assembled packed information consecutive likelihood proportion test (in reverse GCD-SPRT) utilizing compacted information tests in successive identification, while CS recuperation is just sought after when required. This technique altogether diminishes the compressed sensing recuperation overhead, and on different exploits successive location to increase the detecting excellence. Moreover, we project an inside and out detecting plan to quicken detecting basic leadership when an adjustment in channel position is suspicious, (b) a square scanty CS remaking calculation to abuse the square sparsityfeatures of wide range, and (c) a lot of plans to meld results from the recuperated range signs to additionally improve the general detecting exactness. Broad execution assessment results demonstrate that the projected plans can altogether outflank peer conspires below adequately low SNR properties.

Vertical transmission and successive location of symbiotic bacteria during embryo development and larva formation in Corticium candelabrum (Porifera: Demospongiae)

This study reports on the transfer of heterotrophic bacteria from parental tissue to oocytes in the Mediterranean bacteriosponge Corticium candelabrum (Homosclerophorida) and the description of the successive locations of the microsymbionts during embryo development through transmission and scanning electron microscopy. Eight different types of symbiotic bacteria are described morphologically. These eight bacteria morphotypes are found in both adult individuals and larvae. Symbiotic bacteria are transferred to oocytes, but not to spermatocytes. Bacteria are first located at the oocyte periphery below a thick collagen layer and then they migrate to the oocyte cytoplasm, forming spherical clusters. After cleavage, the bacteria can be found in the free space between blastomeres but mainly accumulate at the embryo periphery below the follicular cells that surround the embryo. Once the blastocoel is formed, the symbiotic bacteria move to this central cavity where they actively divide by bipartition, increasing their number considerably. Many examples of phagocytosed bacteria in the proximal zone of the larval cells are observed at this stage. Consequently, bacteria may represent a complementary source of energy for free larvae and settlers before they are able to capture food from the surrounding water.