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A solar-pumped laser (SPL) that converts sunlight directly into a coherent and intense laser beam generally requires a large concentrating lens and precise solar tracking, thereby limiting its potential utility. Here, we demonstrate a fully-planar SPL without a lens or solar tracking. A Nd3+-doped silica fiber is coiled into a cylindrical chamber filled with a sensitizer solution, which acts as a luminescent solar collector. The body of the chamber is highly reflective while the top window is a dichroic mirror that transmits incoming sunlight and traps the fluorescence emitted by the sensitizer. The laser-oscillation threshold was reached at a natural sunlight illumination of 60% on the top window. Calculations indicated that a solar-to-laser power-conversion efficiency could eventually reach 8%. Such an SPL has potential applications in long-term renewable-energy storage or decentralised power supplies for electric vehicles and Internet-of-Things devices. Solar-pumped laser systems are attractive for applications including hydrogen generation and space propulsion, but current technologies are cumbersome and rely on accurate tracking of the sun’s light. Here, lasing is achieved using a planar, luminescent solar collector removing the need for lenses or tracking.

Helically-structured mirrors producing circular Bragg reflection, used as laser mirrors for the twisted-mode operation of compact single frequency microchip lasers, offer better suppression of dual polarization oscillation than linear birefringent nanostruchrred mirrors.

We demonstrate a solar-powered laser (SPL) that does not rely on any concentrator optics or solar tracking system. We believe that the utility of such “unconcentrated” SPLs has considerably increased for energy conversion applications. The proposed SPL consists of a Nd3+-doped fiber as an active medium, a liquid sensitizer, and a housing in which the transmittance of the front window is tailored to work as a luminescent solar collector. The very simple structure of the proposed SPL can be mass-produced easily at a low cost. The lasing threshold is 0.07 W/cm2 (70% of natural sunlight) which is four orders of magnitude smaller than those of conventional SPLs, and the output power at the pumping intensity of 0.1 W/cm2 is 0.25 mW. The SPL exhibits several lasing peaks between 1095 and 1105 nm.

Exceptional points (EPs) in the polarization space were observed in reflection on helically structured thin films. These films have form anisotropy at the nanoscale introduced through dynamic control of crystalline growth geometry by changing the orientation of the substrate with respect to the impinging vapor. They are simpler alternatives to metasurfaces, because they can be produced at low cost using conventional thin-film deposition techniques. The EPs were experimentally confirmed by eigenstate swapping on a closed circuit surrounding them and were predicted by numerical calculations. Reflective surfaces operating at an EP could be used to make ultrasensitive sensors.

Multimode laser emission generally takes place in homogeneously broadened gain media placed inside a standing-wave resonator due to spatial hole burning. Solutions proposed to eliminate this phenomenon have so far involved the use of intracavity elements, such as an etalon, wave plates or saturable absorbers. We propose a monolithic solution, wherein birefringent layers of T i O 2 are deposited on both laser mirrors. This solution enables one to control the contrast of the interference pattern of the standing wave inside the resonator, and thus the strength of the spatial hole burning, by rotating one mirror around the optical axis. A monochromatic laser emission is demonstrated in a quasi-continuous-wave laser-diode-pumped Y b 3 + : Y A G laser experiment.

The concept of the twisted-mode laser operation, which suppresses spatial hole burning and produces single-mode operation in a standing-wave resonator, is revisited for the case of optically anisotropic laser mirrors presenting arbitrary birefringent and dichroic properties. Our analysis clarifies the relationship between the mirrors’ optical properties and the proximity of the polarization states of the counterpropagating waves, which determines the contrast of the standing-wave pattern inside the resonator. The intensity of the principal mode and the population of the upper laser level as a function of the pumping rate are then determined analytically, which enables estimates of the slope efficiency and threshold of multimode emission for a given contrast value of the standing wave. The inversion density is found to reach an upper bound as a function of the pumping rate for every value of the contrast except unity. The design rules for anisotropic mirrors to produce single-frequency operation are provided that are less strict than those to achieve pure twisted-mode operation.

Background There is a growing interest in the effects of probiotics for the prevention and treatment of skin diseases due to their immunomodulatory and antiinflammatory properties. Objective To assess a mixture of five bacterial strains in the prevention of chronic skin inflammation in mice. Methods Hairless SKH-1 mice received daily oral treatment with the probiotic mixture at the dose of 1x109 Colony-Forming Unit (CFU)/day (or vehicle) for three weeks. Chronic skin inflammation was induced by repeated applications of 12-O-tetradecanoylphorbol-13- acetate (TPA; control mice received acetone). Macroscopic and microscopic evaluations of skin lesions were performed and serum levels of interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, IL-17, IL-22, IL-10 and IL-4 measured at the end of the study. Results Treatment with the probiotic mixture significantly limited the induced chronic skin inflammation at both the macroscopic and microscopic levels. This limitation was consistent with downregulated levels of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α, IL- 17 and IL-22) and up-regulated levels of the anti-inflammatory cytokines, IL-10 and IL-4. Conclusion The results suggest that the probiotic mixture tested could help in preserving skin integrity and homeostasis and that its use could be beneficial in dermatological conditions such as atopic dermatitis and psoriasis.

We present the design and experimental characterization of nanostructured laser mirrors aimed at suppressing spatial hole burning (SHB) of a standing wave resonator. The dielectric Bragg mirrors were made by GLancing Angle Physical Vapor Deposition. Two designs are presented. First, helically-nanostructured materials that produce circular Bragg resonance at the wavelength matching the helical period. Second, thick anisotropic coatings deposited on ordinary mirrors, which act as half-wave plates to produce twisted mode laser operation. Both designs enable single longitudinal mode laser operation by suppressing SHB.

Introduction: Clenbuterol has been used to alleviate chronic obstructive pulmonary disease and elicit an anabolic response in muscles. The aim of this study was to determine the influence of muscle mass variation on physical capacities in rats. Methods: The left hindlimbs of Wistar rats were immobilized for 20 days in plantarflexion with a splint and then remobilized for 16 days. The effect of a non-myotoxic dose of clenbuterol during the immobilization period was evaluated. Physical capacities were coordination, free locomotion, grip strength, and bilateral deficit. Results: Immobilization induced a loss of muscle mass, coordination, and strength without any effect on free locomotion. The positive anabolic effect of clenbuterol did not prevent a loss of physical capacities resulting from immobilization. Conclusions: Muscle mass correlated strongly with coordination and isometric strength in untreated rats. Anabolic effect, fiber phenotype modification, and perturbation in neuromuscular communication with clenbuterol improved muscle mass, but it altered physical capacities. Muscle Nerve 52: 1078–1087, 2015

A Monte Carlo ray-tracing simulation was developed for a transversely excited solar-pumped fiber laser without focusing optics. To make this possible, the fiber is immersed in a liquid sensitizer and sandwiched between highly reflective mirrors. The top reflector is dichroic to transmit solar radiation but reflect fluorescence to confine photons that match the absorption band of the active fiber. Simulation was used to evaluate the validity of the concept and optimize device performance. For comparison with the calculations, preliminary experiments were conducted by illuminating a 30 cm aperture, laser module with a solar simulator. The observed gains were in good agreement with the calculations for various conditions, such as sensitizer concentration and mirror reflectivity. Finally, we show that the predicted output power reaches 29 mW when the fiber length is optimized, and it will be enhanced to 150 mW with 0.21% solar-to-laser efficiency under the assumption of a reabsorption-free sensitizer.

The close connection between image formation in geometrical optics and beam transformation by a paraxial optical system is examined analytically using mathematical tools accessible to undergraduate students, such as the Fresnel diffraction integral and Fourier transforms, instead of the more complicated Wigner distribution or coherence functions frequently employed in the literature. It is shown that geometrical optics correctly predicts the plane where a beam is refocused and its magnification only for afocal optical systems or in the limit of point sources. We illustrate this theory by simulating the transformation of a flat-top beam by a pair of lenses.

A study on Laguerre-Gaussian (LG) modes selection in cw and pulsed Nd:YAG or Yb:YAG ceramic lasers pumped by diodes or an external laser source was carried out. Methods of scalar and vector LG modes selection from low to high orders, involving shaping of the pump profile, usage of intra-cavity lenses, uniaxial crystals and polarization selective mirrors, are considered. CCD camera images of beam profiles of hollow scalar LGpm modes (p -radial, m -azimuth indices) of record high-orders and Bessel-like multi-ring modes with highly directional propagation properties are presented. CW and pulsed ceramic lasers with radially or azimuthally polarized LG vector modes of low and high orders are also demonstrated. Applications of the developed laser schemes and LG beams are discussed. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The TLC-Ag dressings, a combination of technology lipido-colloid and silver salts, are used to promote healing in wounds with risks or signs of local infection, thanks to the antimicrobial properties of the silver salts. Nanocrystalline silver dressings containing nanocrystalline silver, also used to improve wound healing, present both antimicrobial and anti-inflammatory effects. The aim of this study was to investigate the anti-inflammatory effects of TLC-Ag dressings in a model of chronic skin inflammation induced by repeated application of 12-O-tetradecanoylphorbol-13-acetate to the skin of hairless mice, in comparison with TLC dressing, Silcryst nanocrystalline dressing, desonide cream 0.05%, a corticoid cream used as positive control, and gauze. Daily treatments of the mice began 7 days after the start of induction of chronic skin inflammation and lasted for 7 days. A macroscopic score was performed daily during the treatment period until the mice killing on day 15 and skin samples were taken for histopathological analysis. TLC-Ag reduced significantly the macroscopic score of chronic skin inflammation from day 10 in comparison with gauze and TLC dressing, similarly to Silcryst nanocrystalline dressing and desonide cream, which presented the best anti-inflammatory effects. No significant differences were observed between TLC dressing and gauze. TLC-Ag reduced significantly the microscopic score of chronic skin inflammation in comparison with TLC dressing and gauze, similarly to Silcryst nanocrystalline dressing but significantly less than desonide cream. These results demonstrate that TLC-Ag dressings present significant anti-inflammatory effects on chronic skin inflammation. They can improve wound healing, due to both the antimicrobial and anti-inflammatory properties.

The increasing prevalence and social burden of subclinical anxiety in the western world represents a significant psychosocial and financial cost. Consumers are favouring a more natural and nonpharmacological approach for alleviating the effects of everyday stress and anxiety. The gamma-aminobutyric acid (GABA) receptor is the primary mediator of central inhibitory neurotransmission, and GABA-receptor agonists are well known to convey anxiolytic effects. Using an in vitro screening approach to identify naturally occurring phytochemical GABA agonists, we discovered the plant secondary metabolite p-coumaric acid to have significant GABAergic activity, an effect that could be blocked by co-administration of the specific GABA-receptor antagonist, picrotoxin. Oral administration of p-coumaric acid to rodents induced a significant anxiolytic effect in vivo as measured using the elevated plus paradigm, in line with the effects of oral diazepam. Given that p-coumaric acid is reasonably well absorbed following oral consumption in man and is relatively nontoxic, it may be suitable for the formulation of a safe and effective anxiolytic functional food.

Chlorella sp. is a green microalgae containing nutrients, vitamins, minerals, and chlorophyll. In some communities, Chlorella sp. is a traditional medicinal plant used for the management of inflammation-related diseases. In a rat model, ROQUETTE Chlorella sp. (RCs) benefits were investigated on visceral pain and associated inflammatory parameters related to cystitis both induced by cyclophosphamide (CYP). RCs was orally administered every day from day 1-16 (250 and 500 mg/kg body weight). Six hours after an intraperitoneal injection of 200 mg/kg body weight of CYP, body temperature, general behavior, food intake, and body weight were recorded. Twenty-four hours after CYP injection, rats were tested in two behavioral tests, an open field and the aversive light stimulus avoidance conditioning test, to evaluate the influence of pain on general activity and learning ability of rats. After euthanasia, bladders were weighed, their thickness was scored, and the urinary hemoglobin was measured. RCs orally administered at the two dosages significantly reduced visceral pain and associated inflammatory parameters related to cystitis both induced by CYP injection, and improved rat behavior. To conclude, RCs demonstrated beneficial effects against visceral pain and cystitis.

Juglans regia L. (walnut) is a plant traditionally used for the treatment of diarrhea. We investigated the antidiarrheal effects of a hydroethanolic leaf extract (HLE) of J. regia against castor oil-induced diarrhea in rats after screening phenolic compounds in the extract. J. regia HLE (0.5, 1, and 2 g/kg by gavage) produced a dose-dependent delay in the onset of diarrhea compared to the vehicle. It also significantly reduced the number of diarrheal feces, fresh weight and water content of the feces, body weight loss and pain at the two highest doses. Loperamide was effective in inhibiting diarrhea and body weight loss but failed to reduce pain. Our findings show that J. regia HLE has a beneficial effect on diarrhea symptoms and associated pain suggesting that it could be an interesting alternative to standard anti-motility drugs. Flavonoids and hydroxycinnamic acids detected in the extract might explain the effects observed.

A polarizing laser mirror made with glancing angle deposition of TiO2 could withstand a train of 2.7 ns pulses with peak power density of around 800 MW/cm2 and a polarization extinction ratio of 1000 when used as an output coupler of a passively Q-switched (Yb0.1Y0.9)3Al5O12 ceramic laser.

Probiotics have been shown to have preventive and therapeutic effects on diarrhea. Because effects tend to be strain specific, benefit of a strain or mixture has to be substantiated by experimental evidence. The aim of this study was to investigate the antidiarrheal and antinociceptive effects of a probiotic mixture (Lactibiane Imedia®, PiLeJe). Castor oil-induced diarrhea test was performed in Wistar rats following oral administration of probiotics (20 × 109, 30 × 109 or 40 × 109 CFU/kg), loperamide (5 mg/kg) or vehicle (water; 10 mL/kg). Time to initial evacuation, number of feces and diarrheal feces, fresh weight and water content of the feces and body weight loss were monitored. Behavioral parameters (eye closing, abnormal posture, activity, fur aspect) were used as pain indices. Probable mechanisms of action were evaluated by using the castor oil-induced enteropooling and charcoal meal transit tests. Probiotics significantly and dose-dependently delayed onset time to first feces and had a beneficial effect on all other parameters (p 90%) at the two highest doses tested (30 × 109 or 40 × 109 CFU/kg) without completely blocking defecation (65.7% at 30 × 109 CFU/kg). Behavioral parameters were improved with probiotics compared to vehicle, improvement that was not observed with loperamide. Probiotics significantly and dose-dependently decreased the volume of intestinal fluid (p

Over the last twenty years, diode pumping of solid-state lasers has opened new prospects for the mode control and formation of Laguerre-Gaussian (LG) beams, enabling a large variety of applications. Experiments on scalar and vector LG modes selection in Nd3+- and Yb3+-doped ceramics and crystal lasers carried out at the Institute for Laser Science, Tokyo are reviewed. Selection of LG modes from low to high orders using intra-cavity elements, polarization-selective mirrors, or shaping the pump beam profile, is considered. Illustrations of record-high-order LG hollow modes, multiring modes with highly directional propagation properties, characteristics of cw and pulsed lasers with radially or azimuthally polarized beams of high polarization purity are presented. General solutions of the wave equation for the axi-symmetric electric field, which describe LG beams of various profiles, are proposed for data analysis. In parallel, a short review on LG modes selection studies carried out at other laboratories is given.

Fluorene is one of the most abundant polycyclic aromatic hydrocarbons (PAHs) in the environment by reason of its high volatility. Demonstrated to be a neurotoxicant through inhalation, it was also identified as a contributive PAH to food contamination. Since no data are available on its oral neurotoxicity, the purpose of the present study was to assess the behavioral and physiological toxicity of repeated oral administration of fluorene to adult Wistar male rats. Animals were daily treated with fluorene at 1, 10 or 100 mg/kg/day for 28 consecutive days. Administration was intraperitoneal (i.p.) or oral (p.o.) to evaluate the influence of the route of exposure on fluorene toxicity. Following this period of treatment, animals in both groups were subjected to similar cognitive evaluations, namely anxiety (elevated-plus maze), locomotor activity (open-field) and learning and memory abilities (eight-arm maze and avoidance test of an aversive light stimulus), as well as physiological measurements. The behavioral testing occurred from the 28th to the 60th day of the experiment during which fluorene treatment continued uninterrupted. At the end of this period, the concentration levels of fluorene and of three of its monohydroxylated metabolites in blood and brain were determined using a GC MS/MS method. The results demonstrated a reduction in rat anxiety level at the lowest doses administered (1 and 10 mg/kg/ day) regardless of the treatment route, whereas locomotor activity and learning abilities remained unchanged. Moreover, a less significant weight gain was noticed in animals i.p.- and p.o.-treated with 100 mg/kg/day during the 28-day period of treatment, which, upon comparison with the three other groups, induced a body weight gap that was maintained throughout the experiment. Significant increases in relative liver weight were also observed in a dose-dependent manner in orally treated rats and only in animal treated i.p. with 100 mg/kg/day. According to the dose, higher concentration levels of fluorene and its monohydroxylated metabolites were measured in blood and brain compartments of i.p.treated rats compared to p.o.-treated animals. In conclusion, fluorene reduced the anxiety level of rats related to dose, treatment route, duration of exposure and blood concentration levels of metabolites.

Numerous studies have indicated that increased vulnerability to oxidative stress may be the main factor involved in functional declines during normal and pathological ageing, and that antioxidant agents, such as polyphenols, may improve or prevent these deficits. We examined whether 1-year administration of a cocoa polyphenolic extract (Acticoa powder), orally delivered at the dose of 24 mg/kg per d between 15 and 27 months of age, affects the onset of age-related cognitive deficits, urinary free dopamine levels and lifespan in old Wistar-Unilever rats. Acticoa powder improved cognitive performances in light extinction and water maze paradigms, increased lifespan and preserved high urinary free dopamine levels. These results suggest that Acticoa powder may be beneficial in retarding age-related brain impairments, including cognitive deficits in normal ageing and perhaps neurodegenerative diseases. Further studies are required to elucidate the mechanisms of cocoa polyphenols in neuroprotection and to explore their effects in man.

Plant extracts are useful in the management of benign prostatic hyperplasia (BPH). This study investigates whether ACTICOA (Barry Callebaut France, Louviers, France) powder (AP), a cocoa polyphenolic extract, could prevent prostate hyperplasia induced by testosterone propionate (TP) in rats. Male Wistar-Unilever rats were randomly divided in four groups of 12 rats: one negative control group receiving subcutaneous injections of corn oil and treated with vehicle and three groups injected subcutaneously with TP and treated with the vehicle (positive control) or AP at 24 (AP24) and 48 (AP48) mg/kg/day. Treatments were given orally and started 2 weeks before the induction of prostate hyperplasia. The influence of TP and AP on body weights and food and water consumption of rats was examined. On day 36, rats were sacrificed, and the prostates were removed, cleaned, and weighed. The prostate size ratio (prostate weight/rat body weight) was then calculated. TP significantly influenced the body weight gain of the rats and their food and water consumption, while AP at both doses tested reduced significantly these differences. TP significantly increased prostate size ratio (P < .001), and this induced increase was significantly inhibited in AP-treated rats in comparison with positive controls (P < .001) in a dose-dependent manner. We conclude that AP can prevent TP-induced prostate hyperplasia and therefore may be beneficial in the management of BPH.

We developed a model of orthotopic transplantation of bladder tumor cells in female Fischer rats using a new reproducible technique. After first performing the mechanical abrasion of a portion of the bladder urothelium with an Abrader© inserted transurethrally via a catheter, we administered a suspension of 5–40 × 106 viable AY-27 tumor cells in sterile phosphate-buffered saline to the bladder cavity. This rapidly led to a tumor growth incidence of approximately 100%. The induced bladder tumors grew expansively into the bladder cavity from the surface (mucosa) and gradually invaded the submucosa, muscles, serosa and surrounding tissue (high-stage invasive transitional cell carcinoma). Size and staging were related to the quantity of tumor cells instilled into the bladder cavity. This model matches the characteristics of human bladder tumor more closely than other bladder cancer models induced with tumor cells. Moreover, it presents many advantages: the method is reproducible, tumors grow rapidly, they are directly attached to the bladder surface and they are always located on the bladder wall, in line with the urethra. This proves especially helpful for evaluating chemotherapeutic agents by different means such as in vivo fluorescence spectroscopy, a noninvasive method used in photodynamic therapy, or other methods designed to detect and treat transitional cell carcinoma. © 2002 Wiley-Liss, Inc.

The human body is constantly exposed to the risk of traumatic lesions. ROQUETTE Schizochytrium sp. (SCs) is a marine microalgae containing large amounts of health-valuable nutrients, more particularly polyunsaturated fatty acids such as docosahexaenoic acid. SCs was investigated by oral administration (125, 250 and 500 mg/kg) and cutaneous application (2.5, 5.0 and 10.0%) to evaluate its impact in two dermatological disorder models in mice: skin inflammation and wound healing. For skin inflammation, it was administered during 14 days starting one week before the induction of chronic skin inflammation by repeated cutaneous application of 12-O-tetradecanoylphorbol 13-acetate (TPA). For wound healing the microalgae was administered after incisional wound healing of the skin until complete wound healing. Results indicated that oral and topical administrations of the two higher doses of SCs had significant effects on macroscopic score of skin inflammation. It had also efficient effect on healing process and duration of wound healing with a dose-response by oral administration and a maximal effect observed from the lowest to the highest dose by topical application. These findings suggest that administration of SCs by both oral and topical routes appeared to have beneficial effects on skin lesions.

The human body is constantly exposed to the risk of traumatic lesions. Chlorella is a green microalgae enriched with nutrients, vitamins, minerals and chlorophyll. In some communities, Chlorella is a traditional medicinal plant used for the management of inflammation-related diseases. ROQUETTE Chlorella sp. (RCs) was investigated by oral administration (125, 250 and 500 mg/kg) and cutaneous application (2.5, 5.0 and 10.0%) to evaluate its impact in two dermatological disorder models in mice: skin inflammation and wound healing. For skin inflammation, it was administered during 14 days starting one week before the induction of chronic skin inflammation by repeated cutaneous application of 12-Otetradecanoylphorbol 13-acetate (TPA). For wound healing the microalgae was administered by topical application after scarification of the skin until complete wound healing. Results indicated that oral and topical administrations of the two higher doses of RCs had significant effects on macroscopic score of skin inflammation with an efficient effect on microscopic score with cutaneous application. The microalgae had also efficient effect on healing process and duration of wound healing for both administration routes and particularly at the two highest doses of RCs. These findings suggest that administration of RCs by both oral and topical routes appeared to have beneficial effects on skin lesions.

International audience; Methyl donor deficiencies and chronic stress cause depression independently, but their interaction has never been thoroughly evaluated. In our study, methyl donor deficient diet and chronic stress condition consisted respectively of a B2, B9, B12, and choline-free diet and a chronic mild stress procedure. Rats were randomly assigned to six groups with three "diet" conditions (free-feeding, pair-fed and methyl donor deficient diet) and two "stress" conditions (no-stress and stress) and were evaluated in the open-field, the elevated plus-maze and the forced swimming test. After the behavioral evaluation, corticosterone and homocysteine plasma levels were measured and dopamine, DOPAC, serotonin, 5HIAA concentrations were evaluated in several brain areas. Rats given a methyl donor deficient diet for 11 weeks causing elevated plasma homocysteine levels were compared to pair-fed and free-feeding rats with or without unpredictable chronic mild stress. Regardless of stress environmental conditions, the methyl donor deficient diet decreased plasma corticosterone levels and caused disinhibition in the elevated plus-maze condition relative to both control groups. However, stress potentiated the effects of the deficient regimen on rearing in the open-field and climbing in the forced swim test. The dietary changes involved in behavior and plasma corticosterone could be caused by homocysteine-induced decreases in dopamine and 5-hydroxytryptamine metabolites in selective brain regions and it can be noted that regardless of stress-conditions, methyl donor deficient diet decreases DOPAC/dopamine and 5HIAA/serotonin ratios in striatum and hypothalamus and selectively 5HIAA/serotonin ratio in the sensorimotor cortex. Our experimental data is particularly relevant in the context of neuropsychiatric disorders frequently associated with folate deficiency and hyperhomocysteinemia.

We report an experimental investigation on the thermal effects in a Nd3+:Y3Al5O12 nanocrystalline-powder random laser with a one-mirror structure by quasi-continuous-wave laser diode pumping. Extremely low thermal conductivity in powder and significant temperature dependence of the narrow emission spectrum of Nd3+:Y3Al5O12 leads to a laser line redshift and gain reduction with a higher heat deposit. Mode drifting induced by the temperature dependence of the refractive index is also discussed.

Room-temperature cw laser oscillations at 1030 and 1075 nm wavelengths were demonstrated for the TEM00 mode with Yb3+:Y2O3 ceramics by LD-pumping. A maximum extraction efficiency of 72% at 1075 nm lasing wavelengths and of 45% at 1030 nm lasing wavelengths were observed.

A polarizing laser mirror was made of an alternating sequence of low and high refractive index layers of titanium oxide using glancing angle deposition (GLAD). Large refractive index contrast and large birefringence, reaching 0.5 and 0.1, respectively, could be obtained from one single raw material by changing the deposition conditions. The laser mirror could withstand a train of 2.7 ns, single-mode pulses at 680 Hz, λ=1030 nm, and peak power density of 670 MW/cm2 when used as an output coupler of a passively Q-switched (Yb0.1Y0.9)3Al5O12 ceramic laser. The polarization extinction ratio was found to be better than 30 dB both in continuous-wave and pulsed regimes. These results indicate that polarizing laser mirrors made from nanostructured thin films with GLAD, in addition to being simple to fabricate, can withstand high pulse energy density.

Bulk laser damage thresholds of doped and undoped ceramic Y3Al5O12 (YAG) materials are reported. These materials were found to resist 100 J/cm2, 4-ns pulses at 1.064 µm wavelength. Single-crystal YAG materials of similar composition yielded similar damage thresholds. Hence, ceramic microstructure does not contribute to lower damage threshold. Beam-size dependence of damage threshold fluence was also studied by repeating the experiment using a lens with a longer focal length. The evolution of damage probability with laser fluence was found to strongly depend on the beam diameter; however, damage threshold was not found to vary significantly with beam diameter.

Aims To further explore the anti-inflammatory properties of d -Limonene. Main methods A rat model was used to compare evolution of TNBS (2,5,6-trinitrobenzene sulfonic acid)-induced colitis after oral feeding with d -Limonene compared to ibuprofen. Peripheral levels of TNF-α (Tumor Necrosis Factor alpha) were assessed in all animals. Cell cultures of fibroblasts and enterocytes were used to test the effect of d -Limonene respectively on TNFα-induced NF-κB (nuclear factor-kappa B) translocation and epithelial resistance. Finally, plasmatic inflammatory markers were examined in an observational study of diet supplementation with d -Limonene-containing orange peel extract (OPE) in humans. Key findings Administered per os at a dose of 10 mg/kg p.o., d -Limonene induced a significant reduction of intestinal inflammatory scores, comparable to that induced by ibuprofen. Moreover, d -Limonene-fed rats had significantly lowered serum concentrations of TNF-α compared to untreated TNBS-colitis rats. The anti-inflammatory effect of d -Limonene also involved inhibition of TNFα-induced NF-κB translocation in fibroblast cultures. The application of d -Limonene on colonic HT-29/B6 cell monolayers increased epithelial resistance. Finally, inflammatory markers, especially peripheral IL-6, markedly decreased upon OPE supplementation of elderly healthy subjects submitted or not to 56 days of dietary supplementation with OPE. Significance In conclusion, d -Limonene indeed demonstrates significant anti-inflammatory effects both in vivo and in vitro. Protective effects on the epithelial barrier and decreased cytokines are involved, suggesting a beneficial role of d -Limonene as diet supplement in reducing inflammation.

Cocoa intake enhances antioxidant defenses quickly and over a short period after ingestion. Epidemiological studies indicate that cocoa has a cardioprotective effect by improving endothelial function and decreasing platelet aggregation and blood pressure. Clinical evidence suggests that cocoa can be a new and interesting food for regulating mood and brain disorders. Cocoa flavonoids have in vitro anti-inflammatory effects, and preclinical studies show this potential. The immunomodulatory power of cocoa, demonstrated preclinically, may be beneficial in reducing certain states of autoimmunity and hypersensitivity. Although in vitro studies have shown that cocoa flavonoids exert antitumoral effects, further studies are needed.

In a recent clinical study, we demonstrated in the general population that Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 (PF) taken in combination for 30 days decreased the global scores of hospital anxiety and depression scale (HADs), and the global severity index of the Hopkins symptoms checklist (HSCL-90), due to the decrease of the sub-scores of somatization, depression and anger-hostility spheres. Therefore, oral intake of PF showed beneficial effects on anxiety and depression related behaviors in human volunteers. From there, it is interesting to focus on the role of this probiotic formulation in the subjects with the lowest urinary free cortisol levels at baseline.This addendum presents a secondary analyse of the effects of PF in a sub-population of 25 subjects with urinary free cortisol (UFC) levels less than 50 ng/ml at baseline, on psychological distress based on the percentage of change of the perceived stress scale (PSs), the HADs and the HSCL-90 scores between baseline and f...

In a previous clinical study, a probiotic formulation (PF) consisting ofLactobacillus helveticusR0052 andBifidobacterium longumR0175 (PF) decreased stress-induced gastrointestinal discomfort. Emerging evidence of a role for gut microbiota on central nervous system functions therefore suggests that oral intake of probiotics may have beneficial consequences on mood and psychological distress. The aim of the present study was to investigate the anxiolytic-like activity of PF in rats, and its possible effects on anxiety, depression, stress and coping strategies in healthy human volunteers. In the preclinical study, rats were daily administered PF for 2 weeks and subsequently tested in the conditioned defensive burying test, a screening model for anti-anxiety agents. In the clinical trial, volunteers participated in a double-blind, placebo-controlled, randomised parallel group study with PF administered for 30 d and assessed with the Hopkins Symptom Checklist (HSCL-90), the Hospital Anxiety and Depression Scale (HADS), the Perceived Stress Scale, the Coping Checklist (CCL) and 24 h urinary free cortisol (UFC). Daily subchronic administration of PF significantly reduced anxiety-like behaviour in rats (P P P P P P P P P L. helveticusR0052 andB. longumR0175 taken in combination display anxiolytic-like activity in rats and beneficial psychological effects in healthy human volunteers.

A new animal model of travelers' diarrhea has been developed by infecting rats orally with a strain of enterotoxigenic Escherichia coli in order to assess the efficacy of three probiotic formulations for the prevention of travelers' diarrhea. Five groups of six rats were given daily (by oral gavage) either a placebo (negative and positive control groups), the suspension of bacterial probiotics called FF1, the yeast probiotic Saccharomyces boulardii, or a combination of both, called Protecflor(TM). After 14 days of treatment, all groups except the negative control one were infected by oral administration of E. coli. Body temperature, body weight, food and water consumption, stools consistency, behavior, and cytokines secretion were disturbed following E. coli infection. Probiotics-treated groups generally displayed less-pronounced symptoms, the combination of probiotics Protecflor(TM) being the most effective.

The effects of Acticoa powder on prostate carcinogenesis were investigated using the N-methylnitrosourea and testosterone propionate prostate tumor model. Sixty male Wistar-Unilever rats were randomly divided in four groups of 15 rats: one control group not induced but treated with vehicle (not induced+vehicle) and three chemo-induced groups. Two weeks before prostate tumor induction and then throughout the experiment, chemo-induced rats were orally treated with Acticoa powder at 24 (chemo-induced+Acticoa powder24) or 48 (chemo-induced+Acticoa powder48) mg/kg or with vehicle (chemo-induced+vehicle), daily from Monday to Friday. Survival, body weight, food and water consumption were recorded throughout the experiment. Six rats per group were randomly killed 9 months after the prostate tumor induction for histopathological analysis of prostates. A reduction in the incidence of prostate tumors was observed for the chemo-induced+Acticoa powder48-treated group in comparison with the chemo-induced+vehicle-treated group and no tumors were observed in the chemo-induced+Acticoa powder24-treated group as in the not induced+vehicle-treated group after 9 months. The nine remaining rats per group were maintained in a long-term survival study. The life span of the chemo-induced+Acticoa powder24-treated group was significantly increased in comparison with the chemo-induced+Acticoa powder48 and the chemo-induced+vehicle-treated groups, close to the one of the not induced+vehicle-treated group. A significant reduction in the incidence of prostate tumors was also observed for the chemo-induced+Acticoa powder24 and chemo-induced+Acticoa powder48-treated groups in comparison with the chemo-induced+vehicle-treated group. In conclusion, Acticoa powder at 24 mg/kg protected rats from prostate carcinogenesis when chronically given before the initiation and promotion phases of induction.

The photoconductivity of high Yb-concentration YAG and Y2O3 samples has been measured, confirming the occurrence of up-conversion in these materials. High intensity pumping reveals a very broad emission spectrum that exhibits avalanche behaviour.

Neodymium-doped silica glass fiber is pumped by a Xe arc lamp as a simulated solar light. The fiber is immersed in rhodamine 6G solution to enhance the photon flux at the 588 nm absorption band of the Nd3+. The chamber that contains the active fiber and dye solution is made of a pair of reflectors. The bottom reflector is highly reflective over the entire visible spectrum, while the top reflector is a short-pass dichroic mirror whose cutoff wavelength is set at 580 nm. As a result, the dye fluorescence of the absorption band is confined by the multiple reflections, like a “greenhouse effect”. The expected confinement factor as a function of the angular-dependent reflectivity of the reflectors is discussed. The highest gain observed is 1.0 ×10-2 m-1 when the lamp light intensity is 2.7 W/cm2.

Reversible jump of thermal emission accompanied with jump of photocurrent is observed in highly doped Yb3+:Y2O3 and Lu2O3 bulk ceramics pumped at 940nm wavelength. In contrast, when these materials are heated with a CO2 laser at 10.6μm wavelength, only a gradual increase of thermal emission and photoconductivity are observed up to the melting point. These results are interpreted as a ytterbium mediated, photoassisted avalanche of thermal emission.

We present a device that can modulate the orbital angular momentum (AOM) of a laser beam The proposed design can be scaled up to several GHz using existing commercial devices, while the output power can also be scaled to values determined by state-of-the-art high-power lasers. This device will find applications in laser processing and for the characterization of metamaterials.