In this article, we introduce a new paradigm of control, called hands-off control, which can save energy and reduce CO2 emissions in control systems. A hands-off control is defined as a control that has a much shorter support than the horizon length. The maximum hands-off control is the minimum support (or sparsest) control among all admissible controls. With maximum hands-off control, actuators in the feedback control system can be stopped during time intervals over which the control values are zero. We show the maximum hands-off control is given by L1 optimal control, for which we also show numerical computation formulas.

microRNAs (miRNAs) are widespread regulators of gene expression, but little is known of their potential roles in congenital muscular dystrophy type 1A (MDC1A). MDC1A is a severe form of muscular dystrophy caused by mutations in the gene encoding laminin α2 chain. To gain insight into the pathophysiological roles of miRNAs associated with MDC1A pathology, laminin α2 chain-deficient mice were evaluated by quantitative PCR. We demonstrate that expression of muscle-specific miR-1, miR-133a, and miR-206 is deregulated in laminin α2 chain-deficient muscle. Furthermore, expression of miR-223 and miR-21, associated with immune cell infiltration and fibrosis, respectively, is altered. Finally, we show that plasma levels of muscle-specific miRNAs are markedly elevated in laminin α2 chain-deficient mice and partially normalized in response to proteasome inhibition therapy. Altogether, our data suggest important roles for miRNAs in MDC1A pathology and we propose plasma levels of muscle-specific miRNAs as promising biomarkers for the progression of MDC1A.

Ključne riječi: biomehanika, opterećenost, kralježnica, softverski paket SAŽETAK: Radno djelovanje zahtijeva stalno mijenjanje položaja da bi se udovoljilo potrebama raznih aktivnosti koje čovjek obavlja tijekom izvršavanja radnih zadataka. Ako se rad obavlja u radnom prostoru koji nije pravilno dizajniran, dolazi do zamora, smanjenja učinkovitosti rada i ugrožavanja zdravlja. Rad predstavlja analizu mogućnosti poboljšanja postojećeg radnog položaja kod ispitanika i proračuna istih vrijednosti sila i momenata na L4 i L5 pršljena kralježnice kao i naprezanja kod određene skupine mišića za radnika u poznatom radnom procesu u odnosu na dopuštena naprezanja. UDK 616.71-001:613.65 PRIMLJENO: 19.11.2013. PRIHVAĆENO: 24.3.2014. OPTEREĆENOST KRALJEŽNICE U FUNKCIJI POKRETA F. Veljović, F. Veljović* SIGURNOST 56 (2) 141 147 (2014)

In this review we summarize our experience gained from several recent ab initio studies aimed to investigate how the competition between short-ranged chemical and long-ranged dispersion interactions determines the bonding mechanism of a specific set of chemically functionalized π-conjugated organic molecules on non-magnetic and magnetic metal surfaces. A key point of this review is to provide a detailed analysis on the issue of how to tune the strength of the organic molecule-surface interaction, such that the nature of the molecular bonding exhibits the specific electronic features of the physisorption or chemisorption bonding mechanisms. In particular, we discuss in detail how the precise control of these bonding mechanisms can be used to design specific electronic and magnetic properties of hybrid organic-metallic interfaces. Furthermore, our first-principles simulations provide not only the basic insights needed to interpret surface-science experiments, but are also a key tool to design organic-substrate systems with tailored properties that can be integrated into future organic-based devices for molecular electronics and molecular spintronics applications.