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### The effect of feedback and information on children's pedometer step counts at school

This study examined whether feedback or feedback plus physical activity information could increase the number of pedometer steps taken during 1 school week. One hundred seventy-seven students (mean age 9.124 ± 1.11 years) in three elementary schools participated. Schools were randomly assigned to control (CON), feedback (FB), or feedback plus information (FB+I) groups. Children wore pedometers during school time for 5 consecutive weekdays. The total steps of the groups were recorded at the end of each school day, with students in the FB and FB+I groups free to view their step counts. In addition, the FB+I group received information and ideas about how they could increase their daily steps. The CON group received no step-count feedback or information. Students in the FB+I group achieved significantly more steps per minute (17.17 ± 4.87) than those in the FB (13.77 ± 4.06, p = 0.003) and CON (12.41 ± 3.12, p = 0.0001) groups. Information, as well as step-count feedback, increased elementary students’ school-based physical activity (number of steps) in the short term. A longer intervention period is necessary to assess the sustained impact of this type of approach

### A Counterexample to Cover's 2P Conjecture on Gaussian Feedback Capacity

We provide a counterexample to Cover's conjecture that the feedback capacity
$C_\textrm{FB}$ of an additive Gaussian noise channel under power constraint
$P$ be no greater than the nonfeedback capacity $C$ of the same channel under
power constraint $2P$, i.e., $C_\textrm{FB}(P) \le C(2P)$.Comment: 2 pages, submitted to IEEE Transactions on Information Theor

### Farmers’ management of functional biodiversity goes beyond pest management in organic European apple orchards

Supporting functional biodiversity (FB), which provides natural pest regulation, is an environmentally sound and promising approach to reduce pesticide use in perennial cultures such as apple, especially in organic farming. However, little is known about farmers’ practices and motivations to implement techniques that favor FB, especially whether or not they really expect anything from FB in terms of pest regulation. In fact, FB-supporting techniques (FB-techniques) are massively questioned by practitioners due to inadequate information about their effectiveness. An interview survey was performed in eight European countries(i) to describe farmers’ practices and identify promising FB-techniques: (ii) to better understand their perceptions of and values associated with FB; and (iii) to identify potential drivers of (non-)adoption. Fifty-five advisors and 125 orchard managers with various degrees of experience and convictions about FB were interviewed and a total of 24 different FB-techniques which can be assigned to three different categories (ecological infrastructures, farming practices and redesign techniques) were described. Some were well-established measures (e.g., hedges and bird houses), while others were more marginal and more recent (e.g., animal introduction and compost). On average, farmers combined more than four techniques that had been implemented over a period of 13 years, especially during their establishment or conversion period. In general, it was difficult for farmers to evaluate the effectiveness of individual FB-techniques on pest regulation. They considered FB-techniques as a whole, targeting multiple species, and valued multiple ecosystem services in addition to pest regulation. The techniques implemented and their associated values differed among farmers who adopted various approaches towards FB. Three different approaches were defined: passive, active and integrated. Their appraisal of FB is even more complex because it may change with time and experience. These findings provide empirical evidence that the practical implementation of promising techniques remains a challenge, considering the diversity of situations and evaluation criteria. Increased cooperation between researchers, farmers and advisors should more effectively target research, advisory support and communication to meet farmers’ needs and perceptions

### Empirical Bayes and Full Bayes for Signal Estimation

We consider signals that follow a parametric distribution where the parameter
values are unknown. To estimate such signals from noisy measurements in scalar
channels, we study the empirical performance of an empirical Bayes (EB)
approach and a full Bayes (FB) approach. We then apply EB and FB to solve
compressed sensing (CS) signal estimation problems by successively denoising a
scalar Gaussian channel within an approximate message passing (AMP) framework.
Our numerical results show that FB achieves better performance than EB in
scalar channel denoising problems when the signal dimension is small. In the CS
setting, the signal dimension must be large enough for AMP to work well; for
large signal dimensions, AMP has similar performance with FB and EB.Comment: This work was presented at the Information Theory and Application
workshop (ITA), San Diego, CA, Feb. 201

### Diffusive capture processes for information search

We show how effectively the diffusive capture processes (DCP) on complex
networks can be applied to information search in the networks. Numerical
simulations show that our method generates only 2% of traffic compared with the
most popular flooding-based query-packet-forwarding (FB) algorithm. We find
that the average searching time, , of the our model is more scalable than
another well known $n$-random walker model and comparable to the FB algorithm
both on real Gnutella network and scale-free networks with $\gamma =2.4$. We
also discuss the possible relationship between and $$, the second
moment of the degree distribution of the networks

### Phenomenology of non-standard Z couplings in exclusive semileptonic b -> s transitions

The rare decays $B\to K^{(*)}\ell^+\ell^-$, $B\to K^{(*)}\nu\bar\nu$ and
$B_s\to\mu^+\mu^-$ are analyzed in a generic scenario where New Physics effects
enter predominantly via $Z$ penguin contributions. We show that this
possibility is well motivated on theoretical grounds, as the $\bar sbZ$ vertex
is particularly susceptible to non-standard dynamics. In addition, such a
framework is also interesting phenomenologically since the $\bar sbZ$ coupling
is rather poorly constrained by present data. The characteristic features of
this scenario for the relevant decay rates and distributions are investigated.
We emphasize that both sign and magnitude of the forward-backward asymmetry of
the decay leptons in $\bar B\to \bar K^*\ell^+\ell^-$, ${\cal A}^{(\bar
B)}_{FB}$, carry sensitive information on New Physics. The observable ${\cal
A}^{(\bar B)}_{FB}+{\cal A}^{(B)}_{FB}$ is proposed as a useful probe of
non-standard CP violation in $\bar sbZ$ couplings.Comment: Minor modifications; version to appear in Phys. Rev.

### Electrolytic lesions within central complex neuropils of the cockroach brain affect negotiation of barriers

Animals must negotiate obstacles in their path in order to successfully function within natural environments. These actions require transitions from walking to other behaviors, many of which are more involved than simple reflexes. For these behaviors to be successful, insects must evaluate objects in their path and then use that information to change posture or re-direct leg movements. Some of this control may occur within a region of the brain known as the central complex (CC). We used discrete electrolytic lesions to examine the role of certain sub-regions of the CC in various obstacle negotiation behaviors. We found that cockroaches with lesions to the protocerebral bridge (PB) and ellipsoid body (EB) exhibit abnormalities in turning and dealing with shelf-like objects; whereas, individuals with lesions to the fan-shaped body (FB) and lateral accessory lobe (LAL), exhibit abnormalities of those behaviors as well as climbing over blocks and up walls to a horizontal plane. Abnormalities in block climbing include decreased success rate, changes in climbing strategy, and delayed response to the block. Increases in these abnormal behaviors were significant in individuals with lesions to the FB and LAL. Although turning abnormalities are present in individuals with lesions to the LAL, EB and the lateral region of the FB, there are some differences in how these deficits present. For instance, the turning deficits seen in individuals with lateral FB lesions only occurred when turning in the direction opposite to the side of the brain on which the lesion occurred. By contrast, individuals with lesions to the EB and LAL exhibited turning abnormalities in both directions. Lesions in the medial region of the FB did not result in directional turning deficits, but in abnormalities in block climbing

### Sequential Necessary and Sufficient Conditions for Capacity Achieving Distributions of Channels with Memory and Feedback

We derive sequential necessary and sufficient conditions for any channel
input conditional distribution ${\cal
P}_{0,n}\triangleq\{P_{X_t|X^{t-1},Y^{t-1}}:~t=0,\ldots,n\}$ to maximize the
finite-time horizon directed information defined by $C^{FB}_{X^n \rightarrow
Y^n} \triangleq \sup_{{\cal P}_{0,n}} I(X^n\rightarrow{Y^n}),~~~ I(X^n
\rightarrow Y^n) =\sum_{t=0}^n{I}(X^t;Y_t|Y^{t-1})$ for channel distributions
$\{P_{Y_t|Y^{t-1},X_t}:~t=0,\ldots,n\}$ and
$\{P_{Y_t|Y_{t-M}^{t-1},X_t}:~t=0,\ldots,n\}$, where
$Y^t\triangleq\{Y_0,\ldots,Y_t\}$ and $X^t\triangleq\{X_0,\ldots,X_t\}$ are the
channel input and output random processes, and $M$ is a finite nonnegative
integer.
\noi We apply the necessary and sufficient conditions to application examples
of time-varying channels with memory and we derive recursive closed form
expressions of the optimal distributions, which maximize the finite-time
horizon directed information. Further, we derive the feedback capacity from the
asymptotic properties of the optimal distributions by investigating the limit
$C_{X^\infty \rightarrow Y^\infty}^{FB} \triangleq \lim_{n \longrightarrow
\infty} \frac{1}{n+1} C_{X^n \rightarrow Y^n}^{FB}$ without any \'a priori
assumptions, such as, stationarity, ergodicity or irreducibility of the channel
distribution. The necessary and sufficient conditions can be easily extended to
a variety of channels with memory, beyond the ones considered in this paper.Comment: 57 pages, 9 figures, part of the paper was accepted for publication
in the proceedings of the IEEE International Symposium on Information Theory
(ISIT), Barcelona, Spain 10-15 July, 2016 (Date of submission of the
conference paper: 25/1/2016

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