Search for: All records

Built infrastructure, such as seawalls and levees, has long been used to reduce shoreline erosion and protect coastal properties from flood impacts. In contrast, natural and nature-based features (NNBF), including marshes, mangroves, oyster reefs, coral reefs, and seagrasses, offer not only coastal protection but also a range of valuable ecosystem services. There is no clear understanding of the capacity of either natural habitats or NNBF integrated with traditional engineered infrastructure to withstand extreme events, nor are there well-defined breakpoints at which these habitats fail to provide coastal protection. Evaluating existing NNBF strategies using a standardized set of metrics can help to assess their effectiveness to better inform design criteria. This review identifies a selection of NNBF projects with long-term monitoring programs and synthesizes the monitoring data to provide a literature-based performance assessment. It also explores the integration of NNBF with existing gray infrastructure to enhance overall effectiveness. 

There is a large body of work studying what forms of computational hardness are needed to realize classical cryptography. In particular, one-way functions and pseudorandom generators can be built from each other, and thus require equivalent computational assumptions to be realized. Furthermore, the existence of either of these primitives implies that $\mathrm{P}\ne \mathrm{N}\mathrm{P}$, which gives a lower bound on the necessary hardness.One can also define versions of each of these primitives with quantum output: respectively one-way state generators and pseudorandom state generators. Unlike in the classical setting, it is not known whether either primitive can be built from the other. Although it has been shown that pseudorandom state generators for certain parameter regimes can be used to build one-way state generators, the implication has not been previously known in full generality. Furthermore, to the best of our knowledge, the existence of one-way state generators has no known implications in complexity theory.We show that pseudorandom states compressing $n$bits to $\log n+1$qubits can be used to build one-way state generators and pseudorandom states compressing $n$bits to $\omega (\log n)$qubits are one-way state generators. This is a nearly optimal result since pseudorandom states with fewer than $c\log n$-qubit output can be shown to exist unconditionally. We also show that any one-way state generator can be broken by a quantum algorithm with classical access to a $\mathrm{P}\mathrm{P}$oracle.An interesting implication of our results is that a $t\left(n\right)$-copy one-way state generator exists unconditionally, for every $t\left(n\right)=o(n/\log n)$. This contrasts nicely with the previously known fact that $O\left(n\right)$-copy one-way state generators require computational hardness. We also outline a new route towards a black-box separation between one-way state generators and quantum bit commitments. 

IntroductionBatrachochytrium salamandrivorans(Bsal) poses a major threat to global amphibian biodiversity. It is essential we understandBsaltransmission to develop better-informed management strategies. Infected carcasses are an important source of transmission for several human and wildlife disease systems; however, they have not been examined as sources forBsalexposure. Here, we evaluated whether infected newt carcasses could contribute toBsaltransmission dynamics. MethodsWe cohoused infected carcasses with susceptible newts in two cohousing chamber types (partitioned or non-partitioned) at three timepoints post-mortem ([0,24[, [24,48, [48,72] hrs). The partitioned chamber prevented newt-to-newt contact hence only allowed indirect, waterborne transmission of zoospores. We measured shedding rates of infected carcasses at each post-mortem timepoint and monitored infection status and mortality of susceptible newts which were exposed during cohousing events. ResultsOur results indicate carcasses are capable of transmittingBsalto susceptible newts up to at least 72 hrs post-mortem, even without live newts directly contacting carcasses. All susceptible newts in each chamber type and post-mortem period became infected and >90% experienced disease-induced mortality.Bsalgenomic copies/uL in skin swabs taken from infected carcasses were high, averaging 7.4x10⁵, 8.6x10⁵, and 2.0x10⁶at 24, 48, and 72 hrs post-mortem, respectively. Water samples collected from cohousing chambers averaged 2743Bsalgenomic copies/uL (approximately 1357 zoospores) and did not decline over 72 hrs. DiscussionOur results indicateBsalinfection can occur rapidly between infected carcasses and susceptible aquatic salamanders via indirect and direct transmission pathways, and carcasses may prolong outbreaks by increasing the duration that infected individuals remain infectious. Carcass removal may be a strategy to reduceBsaltransmission and the impacts of outbreaks. 

Summary The anthropogenic spread of disease from captive to wild amphibian populations (referred to as spillover) is linked to global amphibian declines. Disinfecting procedures and protocols exist to mitigate pathogen transmission to and within natural areas, but understanding of visitor attitudes and behaviour regarding their adoption is limited. We surveyed visitors in two natural areas in a global amphibian biodiversity hotspot to assess their attitudes regarding pathogen spread in such areas and analysed the factors influencing their behavioural intentions to take specific actions to prevent pathogen spillover. Visitors’ willingness to take action was influenced by their attitudes, behavioural control and trust in wildlife/land managers, whereas socio-demographic characteristics were less influential. These findings help us to understand visitor behaviour with respect to amphibian biosecurity in natural areas and inform enhanced biosecurity measures and strategic messaging to reduce pathogen spillover. 

Introduction One of the most important emerging infectious diseases of amphibians is caused by the fungal pathogen Batrachochytrium salamandrivorans (Bsal) . Bsal was recently discovered and is of global concern due to its potential to cause high mortality in amphibians, especially salamander species. To date, little has been reported on the pathophysiological effects of Bsal ; however, studies of a similar fungus, B. dendrobatidis (Bd) , have shown that electrolyte losses and immunosuppression likely play a key role in morbidity and mortality associated with this disease. The goal of this study was to investigate pathophysiological effects and immune responses associated with Bsal chytridiomycosis using 49 rough-skinned newts ( Taricha granulosa ) as the model species. Methods Taricha granulosa were exposed to a 1 × 10 7 per 10 mL dose of Bsal zoospores and allowed to reach various stages of disease progression before being humanely euthanized. At the time of euthanasia, blood was collected for biochemical and hematological analyses as well as protein electrophoresis. Ten standardized body sections were histologically examined, and Bsal -induced skin lesions were counted and graded on a scale of 1–5 based on severity. Results Results indicated that electrolyte imbalances and dehydration induced by damage to the epidermis likely play a major role in the pathogenesis of Bsal chytridiomycosis in this species. Additionally, Bsal -infected, clinically diseased T. granulosa exhibited a systemic inflammatory response identified through alterations in complete blood counts and protein electrophoretograms. Discussion Overall, these results provide foundational information on the pathogenesis of this disease and highlight the differences and similarities between Bsal and Bd chytridiomycosis. 

The emerging fungal amphibian pathogen, Batrachochytrium salamandrivorans (Bsal), is currently spreading across Europe and given its estimated invasion potential, has the capacity to decimate salamander populations worldwide. Fungicides are a promising in situ management strategy for Bsal due to their ability to treat the environment and infected individuals. However, antifungal drugs or pesticides could adversely affect the environment and non-target hosts, thus identifying safe, effective candidate fungicides for in situ treatment is needed. Here, we estimated the inhibitory fungicidal efficacy of five plant-derived fungicides (thymol, curcumin, allicin, 6-gingerol, and Pond Pimafix®) and one chemical fungicide (Virkon® Aquatic) against Bsal zoospores in vitro. We used a broth microdilution method in 48-well plates to test the efficacy of six concentrations per fungicide on Bsal zoospore viability. Following plate incubation, we performed cell viability assays and agar plate growth trials to estimate the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of each fungicide. All six fungicides exhibited inhibitory and fungicidal effects against Bsal growth, with estimated MIC concentrations ranging from 60 to 0.156 μg/mL for the different compounds. Allicin showed the greatest efficacy (i.e., lowest MIC and MFC) against Bsal zoospores followed by curcumin, Pond Pimafix®, thymol, 6-gingerol, and Virkon® Aquatic, respectively. Our results provide evidence that plant-derived fungicides are effective at inhibiting and killing Bsal zoospores in vitro and may be useful for in situ treatment. Additional studies are needed to estimate the efficacy of these fungicides at inactivating Bsal in the environment and treating Bsal-infected amphibians.