Signals for Low Scale Gravity in the Process γγ→ZZ\gamma \gamma \to ZZ

We investigate the sensitivity of future photon-photon colliders to low scale gravity scenarios via the process $\gamma\gamma \to ZZ$ where the Kaluza-Klein boson exchange contributes only when the initial state photons have opposite helicity. We contrast this with the situation for the process $\gamma \gamma \to \gamma \gamma$ where the $t$ and $u$ channel also contribute. We include the one-loop Standard Model background whose interference with the graviton exchange determines the experimental reach in measuring any deviation from the Standard Model expectations and explore how polarization can be exploited to enhance the signal over background. We find that a 1 TeV linear collider has an experimental reach to mass scale of about 4 TeV in this channel.Comment: 20 pages, 8 figure

Conservation with local people: Medicinal plants as cultural keystone species in the Southern Alps

The concept of “cultural keystone species” (CKS) combines ecological and socioeconomic aspects and has a great potential for improving the overall success of conservation and restoration of ecosystems. In our study, we combined an ecological analysis of traditional medicinal plant species with an explorative analysis of the stakeholder landscape to understand the importance of plants for local communities. We investigate the feasibility of the CKS concept for traditional medicinal plants using the Southern Alps (Northern Italy) as a case study. Based on a comprehensive survey of traditional medicinal plants, we analyzed the habitats where they occur and their significance as CKS candidates. We applied the index of identified cultural influence (ICI). We identified some of the relevant stakeholders and their potential interest in traditional medicinal plants. From a total of 273 native medicinal species, we ranked the 10 most important CKS candidates. These comprised species with different ecology such as the herbs Achillea millefolium agg., Alchemilla xanthochlora, Arnica montana, Hypericum perforatum, Matricaria chamomilla, Peucedanum ostruthium, Urtica dioica, the shrub Juniperus communis, and the tree species Betula pendula. By merging their importance for the local communities with their occurrences in the habitats of South Tyrol, the concept of CKS can stimulate species and habitat conservation, and ecosystem restoration

Nonclassical phase-space trajectories for the damped harmonic quantum oscillator

The phase-space path-integral approach to the damped harmonic oscillator is analyzed beyond the Markovian approximation. It is found that pairs of nonclassical trajectories contribute to the path-integral representation of the Wigner propagating function. Due to the linearity of the problem, the sum coordinate of a pair still satisfies the classical equation of motion. Furthermore, it is shown that the broadening of the Wigner propagating function of the damped oscillator arises due to the time-nonlocal interaction mediated by the heat bath.Comment: 8 pages, 3 figures, accepted for publication in Chemical Physic

Floquet-Markov description of the parametrically driven, dissipative harmonic quantum oscillator

Using the parametrically driven harmonic oscillator as a working example, we study two different Markovian approaches to the quantum dynamics of a periodically driven system with dissipation. In the simpler approach, the driving enters the master equation for the reduced density operator only in the Hamiltonian term. An improved master equation is achieved by treating the entire driven system within the Floquet formalism and coupling it to the reservoir as a whole. The different ensuing evolution equations are compared in various representations, particularly as Fokker-Planck equations for the Wigner function. On all levels of approximation, these evolution equations retain the periodicity of the driving, so that their solutions have Floquet form and represent eigenfunctions of a non-unitary propagator over a single period of the driving. We discuss asymptotic states in the long-time limit as well as the conservative and the high-temperature limits. Numerical results obtained within the different Markov approximations are compared with the exact path-integral solution. The application of the improved Floquet-Markov scheme becomes increasingly important when considering stronger driving and lower temperatures.Comment: 29 pages, 7 figure

Lactacidemia in intrauterine growth restricted (IUGR) pregnancies : relationship to clinical severity, oxygenation and placental weight

The aim of the study was to evaluate the impact of clinical severity and placental weight upon fetal lactacidemia in intrauterine growth restricted (IUGR) pregnancies. Seventy pregnancies complicated by IUGR were compared with 70 normal (appropriate for gestational age, AGA) pregnancies at the time of elective cesarean section. IUGR pregnancies were divided according to clinical severity in three groups: Group 1 had normal fetal heart rate (FHR) and normal pulsatility index of the umbilical artery (PI); Group 2 had normal FHR and abnormal PI; and Group 3 had abnormal FHR and PI. No cases with severe lactacidemia had placental weights >or=250 g. Forty-four fetuses had placental weight or=250 g exhibited an F/P ratio significantly lower than that in AGA fetuses suggesting that IUGR may be due to a reduction of placental function per gram of tissue

De novo formation of an aggregation pheromone precursor by an isoprenyl diphosphate synthase-related terpene synthase in the harlequin bug.

Insects use a diverse array of specialized terpene metabolites as pheromones in intraspecific interactions. In contrast to plants and microbes, which employ enzymes called terpene synthases (TPSs) to synthesize terpene metabolites, limited information from few species is available about the enzymatic mechanisms underlying terpene pheromone biosynthesis in insects. Several stink bugs (Hemiptera: Pentatomidae), among them severe agricultural pests, release 15-carbon sesquiterpenes with a bisabolene skeleton as sex or aggregation pheromones. The harlequin bug, Murgantia histrionica, a specialist pest of crucifers, uses two stereoisomers of 10,11-epoxy-1-bisabolen-3-ol as a male-released aggregation pheromone called murgantiol. We show that MhTPS (MhIDS-1), an enzyme unrelated to plant and microbial TPSs but with similarity to trans-isoprenyl diphosphate synthases (IDS) of the core terpene biosynthetic pathway, catalyzes the formation of (1S,6S,7R)-1,10-bisaboladien-1-ol (sesquipiperitol) as a terpene intermediate in murgantiol biosynthesis. Sesquipiperitol, a so-far-unknown compound in animals, also occurs in plants, indicating convergent evolution in the biosynthesis of this sesquiterpene. RNAi-mediated knockdown of MhTPS mRNA confirmed the role of MhTPS in murgantiol biosynthesis. MhTPS expression is highly specific to tissues lining the cuticle of the abdominal sternites of mature males. Phylogenetic analysis suggests that MhTPS is derived from a trans-IDS progenitor and diverged from bona fide trans-IDS proteins including MhIDS-2, which functions as an (E,E)-farnesyl diphosphate (FPP) synthase. Structure-guided mutagenesis revealed several residues critical to MhTPS and MhFPPS activity. The emergence of an IDS-like protein with TPS activity in M. histrionica demonstrates that de novo terpene biosynthesis evolved in the Hemiptera in an adaptation for intraspecific communication

IMMUNOLOGICAL ASPECTS OF CROHN'S DISEASE: A REGULATORY FUNCTION OF TIM-3/GALECTIN-9 IN LYTH1.

Crohn's disease (CD) is a type of inflammatory bowel disease (IBD) and its etiology is multifactorial and involves a combination of genetic environmental factors. The interaction of these factors causes an imbalance of the microbiota, leading to the activation of several immunological and inflammatory mechanism. From an immunological point of view, there seems to be an involvement of the TIM-3/GALECTIN-9 pathway and of the autoregulation of lyTh1. These studies show that in patients with CD the autoregulation of lyth1 is lost due to a reduced concentration of galectin-9 and a reduced TIM-3 expression in LyTh1. This could be one of the reason for the state of perpetual activation of lyTh1, resulting in the chronic inflammation process