Due to its history of language contact with French, modern Vietnamese contains numerous loanwords of French origin, many of which refer to a variety of culturally transmitted items (such as clothing, food, technology, tradeable objects more generally). The present study deals with the phonological aspects of such loans, considering tone, syllable structure and segmental structure. The analysis is based on a corpus of roughly 500 Vietnamese nouns of French origin that, according to native speakers’ judgments, are still in use. As for tonal structure, generalizations about tone assignment made in previous research are modified. The systematic analysis of repair strategies applying to French consonant clusters in onsets and codas shows that Vietnamese generally prefers deletion over epenthesis, unlike many other languages, with two additional repair processes being attested in specific contexts, as well.

We present a general experimental concept for jitter-free pump and probe experiments at free electron lasers. By generating pump and probe pulse from one and the same X-ray pulse using an optical split-and-delay unit, we obtain a temporal resolution that is limited only by the X-ray pulse lengths. In a two-color X-ray pump and X-ray probe experiment with sub 70 fs temporal resolution, we selectively probe the response of orbital and charge degree of freedom in the prototypical functional oxide magnetite after photoexcitation. We find electronic order to be quenched on a time scale of (30 ± 30) fs and hence most likely faster than what is to be expected for any lattice dynamics. Our experimental result hints to the formation of a short lived transient state with decoupled electronic and lattice degree of freedom in magnetite. The excitation and relaxation mechanism for X-ray pumping is discussed within a simple model leading to the conclusion that within the first 10 fs the original photoexcitation decays into low-energy electronic excitations comparable to what is achieved by optical pump pulse excitation. Our findings show on which time scales dynamical decoupling of degrees of freedom in functional oxides can be expected and how to probe this selectively with soft X-ray pulses. Results can be expected to provide crucial information for theories for ultrafast behavior of materials and help to develop concepts for novel switching devices.

Protein homeostasis (proteostasis) is crucial to the maintenance of neuronal integrity and function. As the contact sites between neurons, synapses rely heavily on precisely regulated protein-protein interactions to support synaptic transmission and plasticity processes. Autophagy is an effective degradative pathway that can digest cellular components and maintain cellular proteostasis. Perturbations of autophagy have been implicated in aging and neurodegeneration due to a failure to remove damaged proteins and defective organelles. Recent evidence has demonstrated that autophagosome formation is prominent at synaptic terminals and neuronal autophagy is regulated in a compartment-specific fashion. Moreover, synaptic components including synaptic proteins and vesicles, postsynaptic receptors and synaptic mitochondria are known to be degraded by autophagy, thereby contributing to the remodeling of synapses. Indeed, emerging studies indicate that modulation of autophagy may be required for different forms of synaptic plasticity and memory formation. In this review, I will discuss our current understanding of the important role of neuronal/synaptic autophagy in maintaining neuronal function by degrading synaptic components and try to propose a conceptual framework of how the degradation of synaptic components via autophagy might impact synaptic function and contribute to synaptic plasticity.

The search for neural correlates of operant and observational learning requires a combination of two (experimental) conditions that are very difficult to combine: stable recording from high order neurons and free movement of the animal in a rather natural environment. We developed a virtual environment (VE) that simulates a simplified 3D world for honeybees walking stationary on an air-supported spherical treadmill. We show that honeybees perceive the stimuli in the VE as meaningful by transferring learned information from free flight to the virtual world. In search for neural correlates of learning in the VE, mushroom body extrinsic neurons were recorded over days during learning. We found changes in the neural activity specific to the rewarded and unrewarded visual stimuli. Our results suggest an involvement of the mushroom body extrinsic neurons in operant learning in the honeybee (Apis mellifera).

Elongated landscape features like forest edges, rivers, roads or boundaries of fields are particularly salient landmarks for navigating animals. Here, we ask how honeybees learn such structures and how they are used during their homing flights after being released at an unexpected location (catch-and-release paradigm). The experiments were performed in two landscapes that differed with respect to their overall structure: a rather feature-less landscape, and one rich in close and far distant landmarks. We tested three different forms of learning: learning during orientation flights, learning during training to a feeding site, and learning during homing flights after release at an unexpected site within the explored area. We found that bees use elongated ground structures, e.g., a field boundary separating two pastures close to the hive (Experiment 1), an irrigation channel (Experiment 2), a hedgerow along which the bees were trained (Experiment 3), a gravel road close to the hive and the feeder (Experiment 4), a path along an irrigation channel with its vegetation close to the feeder (Experiment 5) and a gravel road along which bees performed their homing flights (Experiment 6). Discrimination and generalization between the learned linear landmarks and similar ones in the test area depend on their object properties (irrigation channel, gravel road, hedgerow) and their compass orientation. We conclude that elongated ground structures are embedded into multiple landscape features indicating that memory of these linear structures is one component of bee navigation. Elongated structures interact and compete with other references. Object identification is an important part of this process. The objects are characterized not only by their appearance but also by their alignment in the compass. Their salience is highest if both components are close to what had been learned. High similarity in appearance can compensate for (partial) compass misalignment, and vice versa.

Brain collateral circulation is an essential compensatory mechanism in response to acute brain ischemia. To study the temporal evolution of brain macro and microcollateral recruitment and their reciprocal interactions in response to different ischemic conditions, we applied a combination of complementary techniques (T2 weighted magnetic resonance imaging [MRI], time of flight [TOF] angiography [MRA], cerebral blood flow [CBF] imaging and histology) in two different mouse models. Hypoperfusion was either induced by permanent bilateral common carotid artery stenosis (BCCAS) or 60 minute transient unilateral middle cerebral artery occlusion (MCAO). In both models, collateralization is a very dynamic phenomenon with a global effect affecting both hemispheres. Patency of ipsilateral posterior communicating artery (PcomA) represents the main variable survival mechanism and the main determinant of stroke lesion volume and recovery in MCAO whereas the promptness of external carotid artery retrograde flow recruitment together with PcomA patency, critically influence survival, brain ischemic lesion volume and retinopathy in BCCAS mice. Finally, different ischemic gradients shape microcollateral density and size.

Protein homeostasis (proteostasis) is crucial to the maintenance of neuronal integrity and function. As the contact sites between neurons, synapses rely heavily on precisely regulated protein-protein interactions to support synaptic transmission and plasticity processes. Autophagy is an effective degradative pathway that can digest cellular components and maintain cellular proteostasis. Perturbations of autophagy have been implicated in aging and neurodegeneration due to a failure to remove damaged proteins and defective organelles. Recent evidence has demonstrated that autophagosome formation is prominent at synaptic terminals and neuronal autophagy is regulated in a compartment-specific fashion. Moreover, synaptic components including synaptic proteins and vesicles, postsynaptic receptors and synaptic mitochondria are known to be degraded by autophagy, thereby contributing to the remodeling of synapses. Indeed, emerging studies indicate that modulation of autophagy may be required for different forms of synaptic plasticity and memory formation. In this review, I will discuss our current understanding of the important role of neuronal/synaptic autophagy in maintaining neuronal function by degrading synaptic components and try to propose a conceptual framework of how the degradation of synaptic components via autophagy might impact synaptic function and contribute to synaptic plasticity.

R2-like ligand-binding oxidases (R2lox) assemble a heterodinuclear Mn/Fe cofactor which performs reductive dioxygen (O2) activation, catalyzes formation of a tyrosine–valine ether cross-link in the protein scaffold, and binds a fatty acid in a putative substrate channel. We have previously shown that the N-terminal metal binding site 1 is unspecific for manganese or iron in the absence of O2, but prefers manganese in the presence of O2, whereas the C-terminal site 2 is specific for iron. Here, we analyze the effects of amino acid exchanges in the cofactor environment on cofactor assembly and metalation specificity using X-ray crystallography, X-ray absorption spectroscopy, and metal quantification. We find that exchange of either the cross-linking tyrosine or the valine, regardless of whether the mutation still allows cross-link formation or not, results in unspecific manganese or iron binding at site 1 both in the absence or presence of O2, while site 2 still prefers iron as in the wild-type. In contrast, a mutation that blocks binding of the fatty acid does not affect the metal specificity of either site under anoxic or aerobic conditions, and cross-link formation is still observed. All variants assemble a dinuclear trivalent metal cofactor in the aerobic resting state, independently of cross-link formation. These findings imply that the cross-link residues are required to achieve the preference for manganese in site 1 in the presence of O2. The metalation specificity, therefore, appears to be established during the redox reactions leading to cross-link formation.

Paratuberculosis is a major disease in cattle that severely affects animal welfare and causes huge economic losses worldwide. Development of alternative diagnostic methods is of urgent need to control the disease. Recent studies suggest that long non-coding RNAs (lncRNAs) play a crucial role in regulating immune function and may confer valuable information about the disease. However, their role has not yet been investigated in cattle with respect to infection towards Paratuberculosis. Therefore, we investigated the alteration in genomic expression profiles of mRNA and lncRNA in bovine macrophages in response to Paratuberculosis infection using RNA-Seq. We identified 397 potentially novel lncRNA candidates in macrophages of which 38 were differentially regulated by the infection. A total of 820 coding genes were also significantly altered by the infection. Co-expression analysis of lncRNAs and their neighbouring coding genes suggest regulatory functions of lncRNAs in pathways related to immune response. For example, this included protein coding genes such as TNIP3, TNFAIP3 and NF-κB2 that play a role in NF-κB2 signalling, a pathway associated with immune response. This study advances our understanding of lncRNA roles during Paratuberculosis infection.

We study the bulk-boundary correspondence for topological crystalline phases, where the crystalline symmetry is an order-two (anti)symmetry, unitary or antiunitary. We obtain a formulation of the bulk-boundary correspondence in terms of a subgroup sequence of the bulk classifying groups, which uniquely determines the topological classification of the boundary states. This formulation naturally includes higher-order topological phases as well as topologically nontrivial bulk systems without topologically protected boundary states. The complete bulk and boundary classification of higher-order topological phases with an additional order-two symmetry or antisymmetry is contained in this work.

Core-virus like particles (VLPs) assembly is a kinetically complex cascade of interactions between viral proteins, nanoparticle’s surface and an ionic environment. Despite many in silico simulations regarding this process, there is still a lack of experimental data. The main goal of this study was to investigate the capsid protein of hepatitis B virus (HBc) assembly into virus-like particles with superparamagnetic iron oxide nanoparticles (SPIONs) as a magnetic core in relation to their characteristics. The native form of HBc was obtained via agroinfection of Nicotiana benthamiana with pEAQ-HBc plasmid. SPIONs of diameter of 15 nm were synthesized and functionalized with two ligands, providing variety in ζ-potential and hydrodynamic diameter. The antigenic potential of the assembled core-VLPs was assessed with enzyme-linked immunosorbent assay (ELISA). Morphology of SPIONs and core-VLPs was evaluated via transmission electron microscopy (TEM). The most successful core-VLPs assembly was obtained for SPIONs functionalized with dihexadecyl phosphate (DHP) at SPIONs/HBc ratio of 0.2/0.05 mg/mL. ELISA results indicate significant decrease of antigenicity concomitant with core-VLPs assembly. In summary, this study provides an experimental assessment of the crucial parameters guiding SPION-HBc VLPs assembly and evaluates the antigenicity of the obtained structures.

To build a representation of what we see, the human brain recruits regions throughout the visual cortex in cascading sequence. Recently, an approach was proposed to evaluate the dynamics of visual perception in high spatiotemporal resolution at the scale of the whole brain. This method combined functional magnetic resonance imaging (fMRI) data with magnetoencephalography (MEG) data using representational similarity analysis and revealed a hierarchical progression from primary visual cortex through the dorsal and ventral streams. To assess the replicability of this method, we here present the results of a visual recognition neuro-imaging fusion experiment and compare them within and across experimental settings. We evaluated the reliability of this method by assessing the consistency of the results under similar test conditions, showing high agreement within participants. We then generalized these results to a separate group of individuals and visual input by comparing them to the fMRI-MEG fusion data of Cichy et al (2016), revealing a highly similar temporal progression recruiting both the dorsal and ventral streams. Together these results are a testament to the reproducibility of the fMRI-MEG fusion approach and allows for the interpretation of these spatiotemporal dynamic in a broader context.

The search for natural anticancer agents and nanocarrier uses are a part of the current strategies to overcome the side effects caused by chemotherapeutics. Liposomal nanocapsules loaded with purified tarin, a potential immunomodulatory and antitumoral lectin found in taro corms, were produced. Liposomes were composed by 1,2-dioleoyl-sn-glycerol-3-phosphoethanolamine, cholesterylhemisuccinate, and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[folate(polyethylene glycol)-2000 prepared by thin-film hydration. Small unilamellar vesicles were achieved by sonication and extrusion. Scanning electron microscopy evidenced round-shaped nanocapsules presenting a smooth surface, 150 nm diameter and polydispersity index <0.2, estimated by dynamic light scattering. Tarin entrapment rates were over 80% and leakage of ~3% under 40 days of storage at 4 °C. Entrapped tarin exhibited an 83% release after 6 h at pH 4.6–7.4 and 36 °C. Both free and encapsulated tarin exhibited no in vitro toxicity against healthy mice bone marrow and L929 cells but stimulated the production of fibroblast-like and large round-shaped cells. Encapsulated tarin resulted in inhibition of human glioblastoma (U-87 MG) and breast adenocarcinoma (MDA-MB-231) proliferation, with an IC50 of 39.36 and 71.38 µg/mL, respectively. The effectiveness of encapsulated tarin was similar to conventional chemotherapy drugs, such as cisplatin and temozolide. Tarin liposomal nanocapsules exhibited superior pharmacological activity compared to free tarin as a potential chemotherapy adjuvant

The timing regimes of precipitation can exert profound impacts on grassland ecosystems. However, it is still unclear how the peak aboveground biomass (AGBpeak) of alpine grasslands responds to the temporal variability of growing season precipitation (GSP) on the northern Tibetan Plateau. Here, the temporal variability of precipitation was defined as the number and intensity of precipitation events as well as the time interval between consecutive precipitation events. We conducted annual field measurements of AGBpeak between 2009 and 2016 at four sites that were representative of alpine meadow, meadow-steppe, alpine steppe, and desert-steppe. Thus, an empirical model was established with the time series of the field-measured AGBpeak and the corresponding enhanced vegetation index (EVI) (R2 = 0.78), which was used to estimate grassland AGBpeak at the regional scale. The relative importance of the three indices of the temporal variability of precipitation, events, intensity, and time interval on grassland AGBpeak was quantified by principal component regression and shown in a red–green–blue (RGB) composition map. The standardized importance values were used to calculate the vegetation sensitivity index to the temporal variability of precipitation (VSIP). Our results showed that the standardized VSIP was larger than 60 for only 15% of alpine grassland pixels and that AGBpeak did not change significantly for more than 60% of alpine grassland pixels over the past decades, which was likely due to the nonsignificant changes in the temporal variability of precipitation in most pixels. However, a U-shaped relationship was found between VSIP and GSP across the four representative grassland types, indicating that the sensitivity of grassland AGBpeak to precipitation was dependent on the types of grassland communities. Moreover, we found that the temporal variability of precipitation explained more of the field-measured AGBpeak variance than did the total amount of precipitation alone at the site scale, which implies that the mechanisms underlying how the temporal variability of precipitation controls the AGBpeak of alpine grasslands should be better understood at the local scale. We hypothesize that alpine grassland plants promptly respond to the temporal variability of precipitation to keep community biomass production more stable over time, but this conclusion should be further tested. Finally, we call for a long-term experimental study that includes multiple natural and anthropogenic factors together, such as warming, nitrogen deposition, and grazing and fencing, to better understand the mechanisms of alpine grassland stability on the Tibetan Plateau. View Full-Text