Diluted Networks of Nonlinear Resistors and Fractal Dimensions of Percolation Clusters

We study random networks of nonlinear resistors, which obey a generalized Ohm's law, $V\sim I^r$. Our renormalized field theory, which thrives on an interpretation of the involved Feynman Diagrams as being resistor networks themselves, is presented in detail. By considering distinct values of the nonlinearity r, we calculate several fractal dimensions characterizing percolation clusters. For the dimension associated with the red bonds we show that $d_{\scriptsize red} = 1/\nu$ at least to order {\sl O} (\epsilon^4), with $\nu$ being the correlation length exponent, and $\epsilon = 6-d$, where d denotes the spatial dimension. This result agrees with a rigorous one by Coniglio. Our result for the chemical distance, d_{\scriptsize min} = 2 - \epsilon /6 - [ 937/588 + 45/49 (\ln 2 -9/10 \ln 3)] (\epsilon /6)^2 + {\sl O} (\epsilon^3) verifies a previous calculation by one of us. For the backbone dimension we find D_B = 2 + \epsilon /21 - 172 \epsilon^2 /9261 + 2 (- 74639 + 22680 \zeta (3))\epsilon^3 /4084101 + {\sl O} (\epsilon^4), where $\zeta (3) = 1.202057...$, in agreement to second order in $\epsilon$ with a two-loop calculation by Harris and Lubensky.Comment: 29 pages, 7 figure

Unified Methods in Collecting, Preserving, and Archiving Coral Bleaching and Restoration Specimens to Increase Sample Utility and Interdisciplinary Collaboration

Coral reefs are declining worldwide primarily because of bleaching and subsequent mortality resulting from thermal stress. Currently, extensive efforts to engage in more holistic research and restoration endeavors have considerably expanded the techniques applied to examine coral samples. Despite such advances, coral bleaching and restoration studies are often conducted within a specific disciplinary focus, where specimens are collected, preserved, and archived in ways that are not always conducive to further downstream analyses by specialists in other disciplines. This approach may prevent the full utilization of unexpended specimens, leading to siloed research, duplicative efforts, unnecessary loss of additional corals to research endeavors, and overall increased costs. A recent US National Science Foundation-sponsored workshop set out to consolidate our collective knowledge across the disciplines of Omics, Physiology, and Microscopy and Imaging regarding the methods used for coral sample collection, preservation, and archiving. Here, we highlight knowledge gaps and propose some simple steps for collecting, preserving, and archiving coral-bleaching specimens that can increase the impact of individual coral bleaching and restoration studies, as well as foster additional analyses and future discoveries through collaboration. Rapid freezing of samples in liquid nitrogen or placing at −80 °C to −20 °C is optimal for most Omics and Physiology studies with a few exceptions; however, freezing samples removes the potential for many Microscopy and Imaging-based analyses due to the alteration of tissue integrity during freezing. For Microscopy and Imaging, samples are best stored in aldehydes. The use of sterile gloves and receptacles during collection supports the downstream analysis of host-associated bacterial and viral communities which are particularly germane to disease and restoration efforts. Across all disciplines, the use of aseptic techniques during collection, preservation, and archiving maximizes the research potential of coral specimens and allows for the greatest number of possible downstream analyses

Economic Potential of Unmanned Aircraft in Agricultural and Rural Electric Cooperatives

The Association of Unmanned Vehicle Systems International (AUVSI) predicts that 80% of the U.S. unmanned aerial vehicle (UAV) market will be in agricultural and rural areas where cooperatives have a strong presence. Agricultural cooperatives could use UAVs in crop scouting to provide timely high-resolution imagery of crop conditions. Rural electric cooperatives (RECs) could use UAVs to detect line-loss, perform line inspections, and assess storm damage. Our research investigated the level of interest and awareness of these rural cooperatives towards UAVS and analyzed the feasibility of UAV adoption. Surveys were sent to Oklahoma grain and farm supply cooperatives and RECs. The survey investigated the knowledge of and interest in UAVs, and elicited information on crop scouting fees and costs, distribution line inspection costs and preventable line loss. The results indicated a low level of knowledge but a high level of interest in UAV technology. Modeling suggests that UAV applications could be feasible for both REC and agricultural cooperatives. Final regulations from the Federal Aviation Administration, particularly restrictions on line-of-sight operation and altitude appear to be a major impediment to UAV adoption. Our survey results suggest that REC applications would be particularly sensitive to the regulatory structure

In vivo T cell activation induces the formation of CD209(+) PDL-2(+) dendritic cells.

Two critical functions of dendritic cells (DC) are to activate and functionally polarize T cells. Activated T cells can, in turn, influence DC maturation, although their effect on de novo DC development is poorly understood. Here we report that activation of T cells in mice, with either an anti-CD3 antibody or super antigen, drives the rapid formation of CD209(+)CD11b(+)CD11c(+) MHC II(+) DC from monocytic precursors (Mo-DC). GM-CSF is produced by T cells following activation, but surprisingly, it is not required for the formation of CD209(+) Mo-DC. CD40L, however, is critical for the full induction of Mo-DC following T cell activation. T cell induced CD209(+) Mo-DC are comparable to conventional CD209(-) DC in their ability to stimulate T cell proliferation. However, in contrast to conventional CD209(-) DC, CD209(+) Mo-DC fail to effectively polarize T cells, as indicated by a paucity of T cell cytokine production. The inability of CD209(+) Mo-DC to polarize T cells is partly explained by increased expression of PDL-2, since blockade of this molecule restores some polarizing capacity to the Mo-DC. These findings expand the range of signals capable of driving Mo-DC differentiation in vivo beyond exogenous microbial factors to include endogenous factors produced following T cell activation

A Macrophage Colony-Stimulating-Factor-Producing gamma delta T Cell Subset Prevents Malarial Parasitemic Recurrence

Item does not contain fulltex

Allogeneic IgG combined with dendritic cell stimuli induce antitumour T-cell immunity.

Whereas cancers grow within host tissues and evade host immunity through immune-editing and immunosuppression, tumours are rarely transmissible between individuals. Much like transplanted allogeneic organs, allogeneic tumours are reliably rejected by host T cells, even when the tumour and host share the same major histocompatibility complex alleles, the most potent determinants of transplant rejection. How such tumour-eradicating immunity is initiated remains unknown, although elucidating this process could provide the basis for inducing similar responses against naturally arising tumours. Here we find that allogeneic tumour rejection is initiated in mice by naturally occurring tumour-binding IgG antibodies, which enable dendritic cells (DCs) to internalize tumour antigens and subsequently activate tumour-reactive T cells. We exploited this mechanism to treat autologous and autochthonous tumours successfully. Either systemic administration of DCs loaded with allogeneic-IgG-coated tumour cells or intratumoral injection of allogeneic IgG in combination with DC stimuli induced potent T-cell-mediated antitumour immune responses, resulting in tumour eradication in mouse models of melanoma, pancreas, lung and breast cancer. Moreover, this strategy led to eradication of distant tumours and metastases, as well as the injected primary tumours. To assess the clinical relevance of these findings, we studied antibodies and cells from patients with lung cancer. T cells from these patients responded vigorously to autologous tumour antigens after culture with allogeneic-IgG-loaded DCs, recapitulating our findings in mice. These results reveal that tumour-binding allogeneic IgG can induce powerful antitumour immunity that can be exploited for cancer immunotherapy

T cell activation mobilizes monocytes into LNs and promotes formation of CD209⁺ DC.

<p>A) Mice were injected in the footpad with 10µg anti-CD3 or an isotype control antibody. 18 hours later cells from the draining LNs were stained for the early T cell activation marker CD69. Cells shown were gated on DAPI^-, Thy1.2⁺ cells. N=2 per group. Both duplicates are shown. B) Mice were injected in the footpad with 10µg anti-CD3 or PBS. 18 hours later, bone marrow, cardiac blood or draining LNs were stained for DAPI^-, side scatter ^-/int, CD11b⁺, CD11c^-, Ly6c⁺ monocytes. Shown are mean cell percentage and SEM, N=2 mice per group. C) Mice were injected in the footpad with 10µg anti-CD3 or PBS. 18 hours later, draining LNs were evaluated for the frequency of CD11b⁺ CD11c⁺ DC or CD11b⁺ CD11c^- monocytes. Shown is one example representative of more than 5 individual experiments. D) Mice were injected in the footpad with 10µg anti-CD3, isotype control, anti-CD28 or PBS. The absolute number of CD209⁺, CD11b⁺, CD11c⁺, MHC II⁺, CD40⁺, Ly6c^-, DAPI^- DC from 3 draining LNs is shown. Shown are mean cell number and SEM, N=4, representative of more than 5 individual experiments. E) Shown is one example of CD209 staining compared to isotype control staining of LN CD11c⁺, CD11b⁺ DC 18 hours after anti-CD3 antibody injection. The results shown are representative of 2 independent experiments. F) Mice were injected in the footpad with the indicated amounts of anti-CD3 antibody. 18 hours later the absolute number of LN CD209⁺ DC was determined with flow cytometry. G) Mice were injected in the footpad with 10µg anti-CD3 or an isotype control. 18 hours later draining LNs were removed, fixed and frozen. The sections were then stained for the presence of CD209 and B220. The scale bar is 50µM. H) Mice were injected IV with 25µg TSST-1 or PBS. 16 hours later, both inguinal and brachial LNs were harvested and the absolute number of CD209⁺, CD11b⁺, CD11c⁺, MHC II⁺, CD40⁺, Ly6c^-, DAPI^- DC are shown as mean and SEM, N=4 mice per group.</p

Activated T cell driven CD209⁺ Mo-DC stimulate T cell proliferation, but do not induce T cell polarization.

<p>A) Mice were injected in the footpad with 10µg anti-CD3. 18 hours later, LN monocytes gated as Ly6c⁺, CD11c^-, side scatter^{lo/inT cells}, Mo-DC gated as Ly6c^-, CD11c⁺, CD209⁺, CD205^- cells and cDC gated as Ly6c^-, CD11c⁺, CD209^-, CD205⁺ cells were evaluated for expression of various surface proteins. Shown is a representative example from one mouse. B) The gating scheme for sorting CD209⁺ Mo-DC and CD209^- cDC is shown. C) DC sorted as in B) were plated on cover slip bottom chamber slides in medium and immediately imaged. The scale bar is 20µM. D) Cells sorted as in B) along with monocytes and B-cells were pulsed with 2.5µg/ml MHC class II restricted OVA peptide ISQ for 90 minutes at 37°C. They were then washed twice and plated at various ratios with OT-II CD4⁺ T cells from RAG KO mice. After 72 hours the cells were pulsed with H³-thymidine and harvested 18 hours later. Results of triplicate cultures are shown as mean and SEM, and are representative of 3 independent experiments. E) Cultures were set up as in D) except in some conditions 1µg/ml LPS was added during pulsing with peptide. After 72 hours, the cell-free supernatant was harvested and cytokines were measured by ELISA. Results are shown as mean and SEM, performed in triplicate from the 1 DC : 20 T cells condition, and are representative of 3 independent experiments. ND = not detected.</p