-Luby Transform codes (LT) were originally designed for the Binary Erasure Channel (BEC) encountered owing to randomly dropped packets in the statistical multiplexing aided classic wireline-based Internet, where transmitted packets are not affected by the fading or noise of the propagation environment of the wireless Internet. For the sake of transmitting data over the BEC routinely encountered in statistical multiplexing aided wireless Internet -style scenarios, we applied the belief propagation algorithm for decoding LT codes and designed a novel version of LT codes, which we refer to as systematic LT codes. When using soft decoding of the proposed systematic LT code, the decoding process becomes capable of preventing the potentially avalanche-like inter-packet error propagation. For example, the systematic LT(1000,3000) code achieved a BER below 10 −5 at E b /N 0 = 3.5dB after six decoding iterations. An even lower E b /N 0 of 2.7dB was required, when using a longer systematic LT(10000,30000) code for transmission over the AWGN channel. In the combined BEC-AWGN channel the BER recorded at the output of the systematic LT(1000,3000) code was about 10 −5 at E b /N 0 = 4.5dB, when encounter an erasure probability of P e = 0.1.

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We present ez-Segway, a decentralized mechanism to consistently and quickly update the network state while preventing forwarding anomalies (loops and black-holes) and avoiding link congestion. In our design, the centralized SDN controller only pre-computes information needed by the switches during the update execution. This information is distributed to the switches, which use partial knowledge and direct message passing to efficiently realize the update. This separation of concerns has the key benefit of improving update performance as the communication and computation bottlenecks at the controller are removed. Our evaluations via network emulations and large-scale simulations demonstrate the efficiency of ez-Segway, which compared to a centralized approach, improves network update times by up to 45% and 57% at the median and the 99 th percentile, respectively. A deployment of a system prototype in a real OpenFlow switch and an implementation in P4 demonstrate the feasibility and low overhead of implementing simple network update functionality within switches.

Store-operated Ca2+ entry (SOCE) has recently been shown to be of physiological and pathological importance in the heart, particularly during cardiac hypertrophy. However, measuring changes in intracellular Ca2+ during SOCE is very difficult to study in adult primary cardiomyocytes. As a result there is a need for a stable and reliable in vitro model of SOCE which can be used to test cardiac drugs and investigate the role of SOCE in cardiac pathology. HL-1 cells are the only immortal cardiomyocyte cell line available that continuously divides and spontaneously contracts while maintaining phenotypic characteristics of the adult cardiomyocyte. To date the role of SOCE has not yet been investigated in the HL-1 cardiac cell line. We report for the first time that these cells express stromal interaction molecule 1 (STIM1) and the Ca2+ release-activated Ca2+ (CRAC) channel Orai1, which are essential components of the SOCE machinery. In addition, SOCE is tightly coupled to sarcoplasmic reticulum (SR)-Ca2+ release in HL-1 cells, and such response was not impaired in the presence of voltage dependent Ca2+ channels (L-type and T-type channels) or reverse mode Na+/ Ca2+ exchanger (NCX) inhibitors. We were able to abolish the SOCE response with known SOCE inhibitors (BTP-2 and SKF-96365) and by targeted knockdown of Orai1 with RNAi. In addition, knockdown of Orai1 resulted in lower baseline Ca2+ and an attenuated response to thapsigargin (TG) and caffeine, indicating that SOCE may play a role in Ca2+ homeostasis during unstressed conditions in cardiomyocytes. Currently, there is little knowledge about SOCE in cardiomyocytes, and the present results suggest that HL-1 cells will be of great utility in investigating the role of SOCE in the heart.