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We report, to the best of our knowledge, the first use of KY(WO 4 ) 2 and KG(WO 4 ) acousto-optical Q-switches in 3-μm powerful lasers. Q-switches of two different designs (normal incidence with antireflection coatings, and Brewster-angle cut crystals) operate in lasers based on Er:YAG, Cr:Yb:Ho:YSGG, and Cr:Er:YSGG laser crystals. Gain and lifetime of laser crystals significantly influence the regime of Q-switched generation. Er:YAG and Cr:Yb:Ho:YSGG lasers deliver pulses with 10.8 mJ and 17.5 mJ energy, respectively. Pulses with energy of 29.6 mJ and duration of 75 ns in the TEM 00 mode are obtained in a Cr:Er:YSGG laser. The energy is scaled up to 85.7 mJ in the two-stage master oscillator power amplifier system. Powerful laser systems of this kind are in the region of interest for pumping other mid-IR laser media (e.g., Fe:ZnSe and Fe:CdSe), OPOs, CO 2 lasers, and amplifiers. Preliminary experiments on microstructuring of transparent materials by the laser-induced backside wet etching method demonstrate the potential of such lasers to build the foundation for dye-free tissue and cell engineering concepts.

As the prevalence of diabetes is increasing worldwide, research on some of the lesser-known effects, including impaired bone health, are gaining a lot of attention. The two most common forms of diabetes are type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). These two differ in their physiology, with T1DM stemming from an inability to produce insulin, and T2DM involving an insufficient response to the insulin that is produced. This review aims to highlight the most current information regarding diabetes as it relates to bone health. It looks at biochemical changes that characterize diabetic bone; notably increased adiposity, altered bone metabolism, and variations in bone mineral density (BMD). Then several hypotheses are analyzed, concerning how these changes may be detrimental to the highly orchestrated processes that are involved in bone formation and turnover, and ultimately result in the distinguishing features of diabetic bone. The review proceeds by explaining the effects of antidiabetes medications on bone health, then highlighting several ways that diabetes can play a part in other clinical treatment outcomes. With diabetes negatively affecting bone health and creating other clinical problems, and its treatment options potentiating these effects, physicians should consider the use of anti-osteoporotic drugs to supplement standard anti-diabetes medications in patients suffering with diabetic bone loss., Competing Interests: Conflict of interest statement: The authors declare that there is no conflict of interest.

Stem cell research has been a popular topic in the past few decades. This review aims to discuss factors that help regulate, induce, and enhance mesenchymal stem cell (MSC) differentiation into osteoblasts for bone regeneration. The factors analyzed include bone morphogenic protein (BMP), transforming growth factor β (TGF-β), stromal cell-derived factor 1 (SDF-1), insulin-like growth factor type 1 (IGF-1), histone demethylase JMJD3, cyclin dependent kinase 1 (CDK1), fucoidan, Runx2 transcription factor, and TAZ transcriptional coactivator. Methods promoting bone healing are also evaluated in this review that have shown promise in previous studies. Methods tested using animal models include low intensity pulsed ultrasound (LIPUS) with MSC, micro motion, AMD3100 injections, BMP delivery, MSC transplantation, tissue engineering utilizing scaffolds, anti-IL-20 monoclonal antibody, low dose photodynamic therapy, and bone marrow stromal cell transplants. Human clinical trial methods analyzed include osteoblast injections, bone marrow grafts, bone marrow and platelet rich plasma transplantation, tissue engineering using scaffolds, and recombinant human BMP-2. These methods have been shown to promote and accelerate new bone formation. These various methods for enhanced bone regeneration have the potential to be used, following further research, in clinical practice., (© 2017 Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.)

Acousto-optical characteristics of double potassium tungstates are analyzed and specific directions for light modulation are found. First, an important subgroup of elasto-optic coefficients of KYb(WO 4 ) 2 and KLu(WO 4 ) 2 crystals are calculated with use of experimental data. It is revealed that with proper choice of ultrasound direction the acousto-optical figure-of-merit approximately 2 times exceeds the maximum value detected in previous experiments. Another unique direction is determined, which permits modulation of randomly polarized light. The elasto-optic characteristics of KYb(WO 4 ) 2 and KLu(WO 4 ) 2 crystals are compared to those of previously investigated materials of the same crystal group: KY(WO 4 ) 2 , KGd(WO 4 ) 2 ., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The elastic and photo-elastic characteristics of four laser crystals KY(WO₄)₂, KGd(WO₄)₂, KYb(WO₄)₂, and KLu(WO₄)₂ are presented. The first pair was reported early, and the last two materials have been investigated for the first time. The full matrix of elastic constants of these monoclinic crystals has been determined. Also, acousto-optical figure of merit for all the basic geometries of isotropic diffraction has been measured. It is proved that potassium rare-earth tungstates has rather good acousto-optical properties and particularly can take place of fused silica in technical applications required high power laser radiation. All the results demonstrate good prospect of these optically bi-axial laser crystals for development of new effective acousto-optical devices., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Cigarette smoking causes acquired cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction and is associated with delayed mucociliary clearance and chronic bronchitis. Roflumilast is a clinically approved phosphodiesterase 4 inhibitor that improves lung function in patients with chronic bronchitis. We hypothesized that its therapeutic benefit was related in part to activation of CFTR. Primary human bronchial epithelial (HBE) cells, Calu-3, and T84 monolayers were exposed to whole cigarette smoke (WCS) or air with or without roflumilast treatment. CFTR-dependent ion transport was measured in modified Ussing chambers. Airway surface liquid (ASL) was determined by confocal microscopy. Intestinal fluid secretion of ligated murine intestine was monitored ex vivo. Roflumilast activated CFTR-dependent anion transport in normal HBE cells with a half maximal effective concentration of 2.9 nM. Roflumilast partially restored CFTR activity in WCS-exposed HBE cells (5.3 ± 1.1 μA/cm(2) vs. 1.2 ± 0.2 μA/cm(2) [control]; P < 0.05) and was additive with ivacaftor, a specific CFTR potentiator approved for the treatment of CF. Roflumilast improved the depleted ASL depth of HBE monolayers exposed to WCS (9.0 ± 3.1 μm vs. 5.6 ± 2.0 μm [control]; P < 0.05), achieving 79% of that observed in air controls. CFTR activation by roflumilast also induced CFTR-dependent fluid secretion in murine intestine, increasing the wet:dry ratio and the diameter of ligated murine segments. Roflumilast activates CFTR-mediated anion transport in airway and intestinal epithelia via a cyclic adenosine monophosphate-dependent pathway and partially reverses the deleterious effects of WCS, resulting in augmented ASL depth. Roflumilast may benefit patients with chronic obstructive pulmonary disease with chronic bronchitis by activating CFTR, which may also underlie noninfectious diarrhea caused by roflumilast.

Faced with sudden environmental changes, animals must either adapt to novel environments or go extinct. Thus, study of the mechanisms underlying rapid adaptation is crucial not only for the understanding of natural evolutionary processes but also for the understanding of human-induced evolutionary change, which is an increasingly important problem [1-8]. In the present study, we demonstrate that the frequency of completely plated threespine stickleback fish (Gasterosteus aculeatus) has increased in an urban freshwater lake (Lake Washington, Seattle, Washington) within the last 40 years. This is a dramatic example of "reverse evolution,"[9] because the general evolutionary trajectory is toward armor-plate reduction in freshwater sticklebacks [10]. On the basis of our genetic studies and simulations, we propose that the most likely cause of reverse evolution is increased selection for the completely plated morph, which we suggest could result from higher levels of trout predation after a sudden increase in water transparency during the early 1970s. Rapid evolution was facilitated by the existence of standing allelic variation in Ectodysplasin (Eda), the gene that underlies the major plate-morph locus [11]. The Lake Washington stickleback thus provides a novel example of reverse evolution, which is probably caused by a change in allele frequency at the major plate locus in response to a changing predation regime.