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Laser-driven neutron sources could offer a promising alternative to those based on conventional accelerator technologies in delivering compact beams of high brightness and short duration. We examine this through particle-in-cell and Monte Carlo simulations that model, respectively, the laser acceleration of protons from thin-foil targets and their subsequent conversion into neutrons in secondary lead targets. Laser parameters relevant to the 0.5 PW LMJ-PETAL and 0.6–6 PW Apollon systems are considered. Owing to its high intensity, the 20-fs-duration 0.6 PW Apollon laser is expected to accelerate protons up to above 100 MeV, thereby unlocking efficient neutron generation via spallation reactions. As a result, despite a 30-fold lower pulse energy than the LMJ-PETAL laser, the 0.6 PW Apollon laser should perform comparably well both in terms of neutron yield and flux. Notably, we predict that very compact neutron pulses, of ∼10 ps duration and ∼100 μm spot size, can be released provided the lead convertor target is thin enough (∼100 μm). These sources are characterized by extreme fluxes, of the order of 1023 n cm−2 s−1, and even ten times higher when using the 6 PW Apollon laser. Such values surpass those currently achievable at large-scale accelerator-based neutron sources (∼1016 n cm−2 s−1), or reported from previous laser experiments using low-Z converters (∼1018 n cm−2 s−1). By showing that such laser systems can produce neutron pulses significantly brighter than existing sources, our findings open a path toward attractive novel applications, such as flash neutron radiography and laboratory studies of heavy-ion nucleosynthesis.

Polycrystalline of [(Na0.535K0.480)0.966Li0.058](Nb0.90Ta0.10)O3 samples were prepared using the high-temperature solid-state reaction technique. X-ray diffraction (XRD) analysis indicates the formation of a single-phase with orthorhombic structure. AC impedance plots were used as tool to analyze the electrical behavior of the sample as a function of frequency at different temperatures. The AC impedance studies revealed the presence of grain effect, from 425°C onwards. Complex impedance analysis indicated non-Debye type dielectric relaxation. The Nyquist plot showed the negative temperature coefficient of resistance (NTCR) characteristic of NKLNT. The AC conductivity results were used to correlate with the barrier hopping (CBH) model to evaluate the binding energy (Wm), the minimum hopping distance (Rmin), the density of states at Fermi level (N(Ef)), and the activation energy of the compound.

Background Previous research suggests that the Mediterranean diet (a diet high in fruits and vegetables, lean protein, legumes, whole grains, and olive oils) provides protective effects against colorectal cancer. However, there has been little research to determine how the Mediterranean diet could help prevent the recurrence of colorectal cancer following chemotherapy treatment. Objective This systematic review assesses the impact of the Mediterranean diet on the rate of recurrence following colorectal cancer treatment. Methods A systematic search on PubMed, UNE Library, and EMBASE was conducted to find all research studies assessing the Mediterranean diet and its effects on colorectal cancer and post-treatment effects. Article titles and abstracts were screened for relevance in addition to full article screening for eligibility and were quality rated based on ANDEAL criteria. Results Sixteen studies met the eligibility criteria and, as a result, were included. One study assessed lifestyle factors; three studies assessed the components of the Mediterranean diet and their effects on colorectal cancer; one study assessed the dietary inflammatory index and its impact on colorectal cancer; five studies assessed adherence to the Mediterranean diet; four studies assessed diet following cancer treatments; and two studies assessed long-term nutritional intervention on cancer recurrence. The results revealed that the Mediterranean diet has a positive impact on reducing the risk of colorectal cancer, with potential health benefits following treatment for colorectal cancer. Limitations in analyzing results include being a time-locked study, inability to access all articles on the topic, use of English-only articles, and limitation of search terms utilized. Conclusions While previous research reveals evidence that the Mediterranean diet reduces the risk of colorectal cancer, there is compelling data to suggest that adherence the Mediterranean diet, as a normal diet pattern following treatment for colorectal cancer, could reduce the rate of recurrence. Future research is needed to examine the effects of the Mediterranean diet following colorectal cancer treatment.

Background: Transcranial laser stimulation is a novel method of noninvasive brain stimulation found safe and effective for improving prefrontal cortex neurocognitive functions in healthy young adults. This method is different from electric and magnetic stimulation because it causes the photonic oxidation of cytochrome-c-oxidase, the rate-limiting enzyme for oxygen consumption and the major intracellular acceptor of photons from near-infrared light. This photobiomodulation effect promotes mitochondrial respiration, cerebrovascular oxygenation and neurocognitive function. Pilot studies suggest that transcranial photobiomodulation may also induce beneficial effects in aging individuals. Objectives: Randomized, sham-controlled study to test photobiomodulation effects caused by laser stimulation on cytochrome-c-oxidase oxidation and hemoglobin oxygenation in the prefrontal cortex of 68 healthy younger and older adults, ages 18–85. Methods: Broadband near-infrared spectroscopy was used for the noninvasive quantification of bilateral cortical changes in oxidized cytochrome-c-oxidase and hemoglobin oxygenation before, during and after 1064-nm wavelength laser (IR-A laser, area: 13.6 cm2, power density: 250 mW/cm2) or sham stimulation of the right anterior prefrontal cortex (Brodmann Area 10). Results: As compared to sham control, there was a significant laser-induced increase in oxidized cytochrome-c-oxidase during laser stimulation, followed by a significant post-stimulation increase in oxygenated hemoglobin and a decrease in deoxygenated hemoglobin. Furthermore, there was a greater laser-induced effect on cytochrome-c-oxidase with increasing age, while laser-induced effects on cerebral hemodynamics decreased with increasing age. No adverse laser effects were found. Conclusion: The findings support the use of transcranial photobiomodulation for cerebral oxygenation and alleviation of age-related decline in mitochondrial respiration. They justify further research on its therapeutic potential in neurologic and psychiatric diseases.

Objectives: To analyze the impact of bilateral cochlear implantation (CI) on perceptual and linguistic development in hearing-impaired children with congenital Cytomegalovirus (CMV) infection., Patients and Method: A retrospective study was performed for the period 1991-2016 in a pediatric CI reference center. Closed Set Word (CSW) recognition scores, Categories of Auditory Performance (CAP) and linguistic level on the MT Lenormand scale (MTL) were compared between bilateral (Bi) and unilateral (Uni) groups 12, 24 and 36 months after first CI (CI-1)., Results: 84 patients with congenital CMV infection who underwent CI were included, in 2 groups: sequential or simultaneous bilateral CI (Bi) (N=20), and unilateral CI (Uni) (N=64). Twelve, 24 and 36 months after CI-1, CSW scores were 35.56%, 64.52% and 82.93% in Uni and 60.3%, 85% (P=0.0084*), and 100% (P=0.00085*) in Bi. CAP scores 12, 24 and 36 months after CI-1 were 2.57, 3.85 and 4.3 in Uni and 3.91 (P=0.0068*), 5.00 (p=0.029*) and 5.50 (P=0.051*) in Bi. MTL linguistic level scores at 12, 24 and 36 months were 0.72, 1.25 and 1.65 in Uni, and 1.72, 3 (P=0.033) and 3.11 (P=0.045) in Bi. These significantly better scores in Bi at 24 and 36 months after CI-1 were also found on analysis of subgroups with no associated neurologic disorder (P=0.046* and P=0.032*), no associated psychiatric pathology (P=0.0055* and P=0.0073*), and no other associated disorder (P=0.0018* and P=0.035*), and for all subgroups together (P=0.0036 and P=0.037)., Conclusion: Bilateral CI is a faster way than unilateral CI for patients with congenital CMV infection to achieve structured fluent oral language. 50% of the series showed cerebral abnormalities on MRI, without difference between groups. This was not in itself predictive of poor progression of oral communication, unless associated with major neurologic disorder. Some children made little or no use of their CI in the medium term., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)

Postmortem lignification of xylem tracheary elements (TEs) has been debated for decades. Here, we provide evidence in Zinnia elegans TE cell cultures, using pharmacological inhibitors and in intact Z. elegans plants using Fourier transform infrared microspectroscopy, that TE lignification occurs postmortem (i.e., after TE programmed cell death). In situ RT-PCR verified expression of the lignin monomer biosynthetic cinnamoyl CoA reductase and cinnamyl alcohol dehydrogenase in not only the lignifying TEs but also in the unlignified non-TE cells of Z. elegans TE cell cultures and in living, parenchymatic xylem cells that surround TEs in stems. These cells were also shown to have the capacity to synthesize and transport lignin monomers and reactive oxygen species to the cell walls of dead TEs. Differential gene expression analysis in Z. elegans TE cell cultures and concomitant functional analysis in Arabidopsis thaliana resulted in identification of several genes that were expressed in the non-TE cells and that affected lignin chemistry on the basis of pyrolysis-gas chromatography/mass spectrometry analysis. These data suggest that living, parenchymatic xylem cells contribute to TE lignification in a non-cell-autonomous manner, thus enabling the postmortem lignification of TEs.

ZnO nanorods were grown on microfibers of Polyethylene terephthalate (PET) fabric by seeding method to develop hierarchical roughness structure. XRD and XPS analysis show the presence of crystalline ZnO and chemical Zn species at the fiber surface at each stage of the process. Five series of samples with different seed concentrations have been realized, and their surface morphology and topography were characterized by AFM and SEM. Increasing seed concentrations lead to samples with superhydrophilic properties. Not only the water contact angle at fabric surface tends to zero but also the water capillary diffusion inside fabric is faster. Nanostructuration affects the structure inside the fabric, and further experiments with decane liquid have been made to get a better understanding of this effect. To study the superhydrophobicity, nanorods treated samples were modified with octadecyltrimethoxysilane (ODS) by two method; solution deposition and vapor deposition. The superhydrophobicity was characterized by measuring the water contact angle and water sliding angle with 5 μl water droplet. The samples modified with ODS by vapor deposition showed higher water contact angles and low water sliding angle than the ones modified with solution method. The lotus effect has been well correlated with the surface morphology of the nanorods structured fibers. The application of the Cassie-Baxter equation is discussed., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Among the various methods exploitable to determine the bioavailability of drugs, reversed-phase liquid chromatography (RPLC) appears to be suited to creation of patterns of prediction. In this context a new stationary phase was designed in this work to reproduce, in terms of chemical structure, as accurately as possible, the main elements of cellular membranes; which include phospholipids and cholesterol molecules. An efficient synthetic pathway was developed to prepare ligands that contain a phosphate head, a long alkyl chain chemically bonded to silica, and a cholesteric moiety, in order to mimic both hydrophilic and hydrophobic interactions, and "membrane-like" organization, respectively. The new stationary phase was characterized by Fourier-transform infra red (FTIR) and (1)H-(13)C, (1)H-(31)P, and (1)H-(29)Si cross-polarization magic-angle-spinning nuclear magnetic resonance (CP MAS NMR) spectroscopy. Its chromatographic behavior has been studied by classical classification tests for RPLC columns. Despite its low surface coverage, the material produced exhibits high shape selectivity, possibly due to the organization of the grafted moieties.

The properties of four cholesteric bonded stationary phases differing in the nature of the spacer and the end-capping were assessed using simple chromatographic tests based on the retention of nonpolar compounds and of planar or nonplanar probe solutes. All cholesteric columns showed a hydrophobicity close to that of conventional octadecyldimethylsilyl (ODS) materials. Non-end-capped cholesteric bonded phases showed greater selectivity than ODS ones and both end-capped cholesteric bonded phases exhibit behavior intermediate between that of the non-end-capped original material and that of the ODS bonded phase.

Nitric oxide (NO) is a diatomic gas that performs crucial functions in a wide array of physiological processes in animals. The past several years have revealed much about its roles in plants. It is well established that NO is synthesized from nitrite by nitrate reductase (NR) and via chemical pathways. There is increasing evidence for the occurrence of an alternative pathway in which NO production is catalysed from L-arginine by a so far non-identified enzyme. Contradictory results have been reported regarding the respective involvement of these enzymes in specific physiological conditions. Although much remains to be proved, we assume that these inconsistencies can be accounted for by the limited specificity of the pharmacological agents used to suppress NO synthesis but also by the reduced content of L-arginine as well as the inactivity of nitrate-permeable anion channels in nitrate reductase- and/or nitrate/nitrite-deficient plants. Another unresolved issue concerns the molecular mechanisms underlying NO effects in plants. Here, we provide evidence that the second messenger Ca2+, as well as protein kinases including MAPK and SnRK2, are very plausible mediators of the NO signals. These findings open new perspectives about NO-based signaling in plants.

Much attention has been paid to nitric oxide (NO) research since its discovery as a physiological mediator of plant defence responses. In recent years, newer roles have been attributed to NO, ranging from root development to stomatal closure. The molecular mechanisms underlying NO action in plants are just begun to emerge. The currently available data illustrate that NO can directly influence the activity of target proteins through nitrosylation and has the capacity to act as a Ca2+-mobilizing intracellular messenger. The interplay between NO and Ca2+ has important functional implications, expanding and enriching the possibilities for modulating transduction processes. Furthermore, protein kinases regulated through NO-dependent mechanisms are being discovered, offering fresh perspective on processes such as stress tolerance.

Seven patients with chronic dorsolumbar pain, stiffness and some restriction of spinal movements are described. Multiple lesions of the vertebral bodies were present. The lesions occurred at various levels and all had similar radiological characteristics, often returning to normal after several years. Vertebral changes of this type may be seen in patients with ankylosing spondylitis but for a variety of cogent reasons presented in this report our patients did not readily fall into this diagnostic group. The aetiology of these vertebral lesions is unknown but available evidence indicates that they should not be attributed to an infectious or neoplastic process.