The mutualistic fungus Piriformospora indica colonizes Arabidopsis roots by inducing an endoplasmic reticulum stress-triggered caspase-dependent cell death

In Arabidopsis thaliana roots, the mutualistic fungus Piriformospora indica initially colonizes living cells, which die as the colonization proceeds. We aimed to clarify the molecular basis of this colonization-associated cell death. Our cytological analyses revealed endoplasmic reticulum (ER) swelling and vacuolar collapse in invaded cells, indicative of ER stress and cell death during root colonization. Consistent with this, P. indica–colonized plants were hypersensitive to the ER stress inducer tunicamycin. By clear contrast, ER stress sensors bZIP60 and bZIP28 as well as canonical markers for the ER stress response pathway, termed the unfolded protein response (UPR), were suppressed at the same time. Arabidopsis mutants compromised in caspase 1–like activity, mediated by cell death–regulating vacuolar processing enzymes (VPEs), showed reduced colonization and decreased cell death incidence. We propose a previously unreported microbial invasion strategy during which P. indica induces ER stress but inhibits the adaptive UPR. This disturbance results in a VPE/caspase 1–like-mediated cell death, which is required for the establishment of the symbiosis. Our results suggest the presence of an at least partially conserved ER stress–induced caspase-dependent cell death pathway in plants as has been reported for metazoans

Indigenous American Fishing Traditions at the First Spanish Capital of La Florida: Santa Elena (1566–1587 CE), South Carolina, USA

Abstract Few studies of post-Columbian animal economies in the Americas elaborate on the influence of traditional Indigenous knowledge on colonial economies. A vertebrate collection from Santa Elena (1566–87 CE, South Carolina, USA), the original Spanish capital of La Florida, offers the opportunity to examine that influence at the first European-sponsored capital north of Mexico. Santa Elena’s animal economy was the product of dynamic interactions among multiple actors, merging preexisting traditional Indigenous practices, particularly traditional fishing practices, with Eurasian animal husbandry to produce a new cultural form. A suite of wild vertebrates long used by Indigenous Americans living on the southeastern North Atlantic coast contributes 87% of Santa Elena’s noncommensal individuals and 63% of the noncommensal biomass. Examples of this strategy are found in vertebrate collections from subsequent Spanish and British settlements. This suggests the extent to which colonists at the Spanish-sponsored colony adopted some Indigenous animal-use practices, especially those related to fishing, and the speed with which this occurred. The new cultural form persisted into the nineteenth century and continues to characterize local cuisines

Flooding and Flow Path Selection on Alluvial Fans and Deltas

The surfaces of alluvial fans and river deltas (collectively fans) are often dissected by a small number of channels radiating from the fan apex. On long timescales, channels migrate via avulsion, the process of channel bed deposition and abandonment that often results in catastrophic flooding and loss of life on densely populated fans. We present results of an experimental fan that creates realistic channel patterns by avulsion. The avulsion cycle occurs with a period that is predictable from conservation of mass. Selection of a new flow path is inherently stochastic; however, once a network of 4–5 channels is established, flow oscillates among these channels indefinitely. We demonstrate that a directed random walk model with memory quantitatively reproduces these dynamics and limiting behavior, and is consistent with natural fans

Dispersive Optical Interface Based on Nanofiber-Trapped Atoms

We dispersively interface an ensemble of one thousand atoms trapped in the evanescent field surrounding a tapered optical nanofiber. This method relies on the azimuthally-asymmetric coupling of the ensemble with the evanescent field of an off-resonant probe beam, transmitted through the nanofiber. The resulting birefringence and dispersion are significant; we observe a phase shift per atom of $\sim$\,1\,mrad at a detuning of six times the natural linewidth, corresponding to an effective resonant optical density per atom of 0.027. Moreover, we utilize this strong dispersion to non-destructively determine the number of atoms.Comment: 4 pages, 4 figure

The facilitatory effect of duloxetine combined with pelvic floor muscle training on the excitability of urethral sphincter motor neurons

INTRODUCTION AND HYPOTHESIS: Aim of this study was to investigate the excitability of sphincter motor neurons under the influence of pelvic floor muscle training (PFMT) and duloxetine. Due to their mechanisms of action, there might be a synergistic effect of duloxetine and PFMT in regard to the facilitation of spinal reflexes controlling urethral sphincter contractions and hence continence. METHODS: In ten healthy female subjects, clitoral electric stimulation (CES) and transcranial magnetic stimulation (TMS) were used to determine individual motor thresholds for external urethral sphincter (EUS) contractions before and after PFMT, duloxetine, and PFMT + duloxetine. RESULTS: PFMT and duloxetine alone significantly decreased the motor thresholds for EUS contractions during CES and TMS. However, the combined treatment reduced the motor threshold for EUS contractions significantly stronger compared to PFMT or duloxetine alone. CONCLUSIONS: The results are suggestive for a synergistic facilitatory effect of PFMT and duloxetine on sphincter motor neuron activation

Poynting's theorem for planes waves at an interface: a scattering matrix approach

We apply the Poynting theorem to the scattering of monochromatic electromagnetic planes waves with normal incidence to the interface of two different media. We write this energy conservation theorem to introduce a natural definition of the scattering matrix S. For the dielectric-dielectric interface the balance equation lead us to the energy flux conservation which express one of the properties of S: it is a unitary matrix. For the dielectric-conductor interface the scattering matrix is no longer unitary due to the presence of losses at the conductor. However, the dissipative term appearing in the Poynting theorem can be interpreted as a single absorbing mode at the conductor such that a whole S, satisfying flux conservation and containing this absorbing mode, can be defined. This is a simplest version of a model introduced in the current literature to describe losses in more complex systems.Comment: 5 pages, 3 figures, submitted to Am. J. Phy

Nonlinear opto-vibronics in molecular systems

We analytically tackle opto-vibronic interactions in molecular systems driven by either classical or quantum light fields. In particular, we examine a simple model of molecules with two relevant electronic levels, characterized by potential landscapes with different positions of minima along the internuclear coordinate and of varying curvatures. Such systems exhibit an electron-vibron interaction, which can be comprised of linear and quadratic terms in the vibrational displacement. By employing a combination of conditional displacement and squeezing operators, we present analytical expressions based on a quantum Langevin equations approach, to describe the emission and absorption spectra of such nonlinear molecular systems. Furthermore, we examine the imprint of the quadratic interactions onto the transmission properties of a cavity-molecule system within the collective strong coupling regime of cavity quantum electrodynamics

Private Landowners’ Willingness to Enroll Their Properties in a Public Hunting Access Program in Northeast Missouri

State wildlife agencies have successfully used public hunting access fees to increase hunting opportunity and to provide a financial incentive to private landowners for maintaining habitat. Typical payments per hectare (ac) include $3.29 ($1.25) on average in Kansas, $2.47-$3.71($1-$1.50) for pheasant hunting in Colorado, $2.47-$12.36 ($1–$5) in North Dakota for pheasant hunting, and $4.45 ($1.80) on average in South Dakota. We studied the USDA Conservation Reserve Program (CRP) in 2004 in Adair, Knox, Macon, Monroe, Ralls, Randolph, Schuyler, and Scotland counties in northeast Missouri as part of a quail and songbird habitat restoration initiative. CRP is prominent in these counties with 83,040 ha (205,197 ac) enrolled. We conducted a mail-back survey of all CRP contract holders, totaling 3,283 landowners to study their willingness to enroll their properties in a hypothetical public- access hunting program. The survey was designed to provide information about landowner demographics, attitudes toward wildlife and hunting, and knowledge of wildlife habitat management aspects of the CRP. We used the Kansas Department of Wildlife and Parks Walk-In Hunting Access Program as an example for questions related to the concept of public-access hunting, and presented landowners with hypothetical annual lease payments for enrolling, using a discrete-choice modeling framework. Survey response rate was relatively high at 59.5%. The average respondent had 34.6 ha (85.5 ac) enrolled in CRP, and field size averaged 6.47 ha (16.0 ac), ranging from 0.04 to 84.9 ha (0.1–209.7 ac). Wildlife as a product of the CRP was ‘very’ or ‘somewhat important’ to 89% of respondents and, among a list of wildlife species and native plants, northern bobwhite (Colinus virginianus) was most popular with 80% of respondents checking ‘very’ or ‘somewhat important’ on the survey. The corresponding values were 53–66% for wild turkey (Meleagris gallopavo), deer, rabbit, pheasant, and songbirds. We asked if landowners would enroll any of their CRP land in a public-access hunting program (PAHP). We used 8 different versions of the survey, each with a different ‘offer’ level in the question to evaluate the potential costs of a PAHP program. The structure of the survey specified whether landowners would accept payment of $X/ac, where X was one value randomly selected from the set of$1, $2,$3, $4,$5, $7,$10, or $20. None of respondents chose ‘yes’ at a PAHP value of$0, 91.9% chose ‘no’, and 8.1% chose ‘don’t know’; respective values ($) and choices ($1-1.7%, 91.3%, and 6.9%; $2-3.0$3-4.0%, 84.9%, and 11.2%; $4-3.4$5- 4.7%, 83.4%, and 11.9%; $7-7.1$10-8.4%, 77.0%, and 14.7%; and $20-14.8$2/ac ($4.94/ha), ~ 3$10,500. About 1,012 ha (2,500 ac) would be designated for quail hunting of this hypothetical PAHP area, based on respondents’ answers to what type of hunting they would allow. We estimate that 5,261 ha (13,000 ac) would be enrolled with 2,489 ha (6,150 ac) open for quail hunting at an annual cost of about $90,000 if the payment level was raised to$7/ac ($17.30/ha). There is potential to improve the feasibility of CRP lands for bobwhite hunting in northeast Missouri by adding a public-access hunting incentive, but managers will be challenged to use this approach successfully. Landowners’ inclination to allow access for deer hunting, but not for quail hunting, reduces an agency’s justification for using quail hunting access as an approach to improve conservation of bobwhites, in addition to the relatively high cost

How to be causal: time, spacetime, and spectra

I explain a simple definition of causality in widespread use, and indicate how it links to the Kramers Kronig relations. The specification of causality in terms of temporal differential eqations then shows us the way to write down dynamical models so that their causal nature /in the sense used here/ should be obvious to all. To extend existing treatments of causality that work only in the frequency domain, I derive a reformulation of the long-standing Kramers Kronig relations applicable not only to just temporal causality, but also to spacetime "light-cone" causality based on signals carried by waves. I also apply this causal reasoning to Maxwell's equations, which is an instructive example since their casual properties are sometimes debated.Comment: v4 - add Appdx A, "discrete" picture (not in EJP); v5 - add Appdx B, cause classification/frames (not in EJP); v7 - unusual model case; v8 add reference