Synchronous mode-locking of solid-state lasers by difference frequency generation.

This Letter introduces a novel, to the best of our knowledge, method for achieving mode-locking and synchronization of mode-locked output pulses from two lasers. The proposed technique leverages parametric gain from difference frequency generation. Specifically, a Nd:YAG laser is mode-locked by single-pass mode-locked pulses from a mode-locked Ti:sapphire laser using an intracavity nonlinear crystal. When the continuous-wave laser is not actively pumped, the system functions as a synchronously pumped optical parametric oscillator. This novel approach has the potential to enable new devices, especially for pump-probe applications or for generation of mode-locked pulses in spectral regions where conventional mode-locked devices are typically not available.

Safety and clinical activity of durvalumab combined with tremelimumab in recurrent/metastatic head and neck squamous cell carcinoma: a multicenter phase I study.

BACKGROUND: Programmed cell death protein 1 (PD-1) inhibitors prolong survival versus chemotherapy in recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC), which often expresses cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death-ligand 1 (PD-L1), providing a rationale for combined PD-(L)1 and CTLA-4 blockade. We report a phase I, open-label study of the PD-L1 inhibitor durvalumab plus the CTLA-4 inhibitor tremelimumab (NCT02262741). METHODS: In dose exploration, two cohorts of previously treated patients received durvalumab 10 mg/kg plus tremelimumab 3 mg/kg, or durvalumab 20 mg/kg plus tremelimumab 1 mg/kg, for up to 12 months. Dose expansion comprised two cohorts of previously untreated patients with R/M HNSCC having baseline PD-L1 tumor cell (TC) expression ≥25% and <25% and one cohort of immunotherapy-pretreated patients with any PD-L1 level. All received durvalumab 20 mg/kg plus tremelimumab 1 mg/kg, then durvalumab 10 mg/kg, for up to 12 months. The primary endpoint was safety. The secondary endpoints were objective response rate (ORR) by RECIST version 1.1, pharmacokinetics, pharmacodynamics, and immunogenicity. RESULTS: A total of 71 patients were treated. The median duration of exposure was 13.6 weeks for durvalumab and 13.1 weeks for tremelimumab. In dose exploration, no dose-limiting toxicities occurred. No maximum tolerated dose was identified. Treatment-related adverse events (TRAEs) occurred in 69.0% of patients; grade 3/4 and serious TRAEs occurred in 31.0% and 18.3%, respectively. TRAEs led to discontinuation in 9.9%. There were no treatment-related deaths. The ORR was 5.6% (95% confidence interval 1.6-13.8), including one complete response and three partial responses, all patients were in dose expansion with PD-L1 TC ≥25% and no prior immunotherapy exposure; three had ongoing responses ≥12 months. The median overall survival in the total population was 8.6 months. Soluble PD-L1 suppression was almost complete in all cohorts, suggesting target engagement. CD4+Ki67+ T cells were significantly elevated in all dose-expansion cohorts. CONCLUSIONS: Treatment was well tolerated. However, response rates were low despite target engagement, no drug-drug interactions, and no drug-neutralizing antibodies to durvalumab.

Bariatric surgeons' views on pre-operative factors associated with improved health-related quality of life following surgery.

Bariatric surgery is an effective treatment for severe obesity, affording significant improvements in weight loss and health-related quality of life. However, bariatric surgeons' views on whether certain pre-operative factors predict improvements in post-operative health-related quality of life, and if so, which ones, are largely unknown. This cross-sectional survey study examined the views of 58 bariatric surgeons from Australia and New Zealand. A total of 18 factors were selected for exploration based on their mention in the literature. Participants rated the extent to which they thought these pre-operative factors would improve post-operative health-related quality of life. Responses showed that bariatric surgeons held diverse perspectives and revealed a lack of consensus regarding "predictive" factors. Generally, respondents agreed that better than average health literacy, higher socioeconomic status, good physical and psychological health, and positive social support were predictors of improved health-related quality of life following surgery. However, poor eating behaviours, smoking, and the use of alcohol or other substances were deemed negative predictors. Interestingly, aside from higher socioeconomic status, good psychological health, and positive social support, none of the aforementioned views aligned with existing literature. This study offers an initial insight into bariatric surgeons' views on the influence of different pre-operative factors on post-operative health-related quality of life. The array of views identified suggests that there may be an opportunity for medical education, but the findings warrant caution due to the sample size. Replication with a larger survey may be useful, especially as predicted health-related quality of life outcomes could guide decisions regarding surgical (non)progression.

SCG variability and spectral energy distribution during normal breathing and breath hold at different lung volumes and airway pressures.

Seismocardiographic (SCG) signals are chest wall vibrations induced by cardiac activity and are potentially useful for cardiac monitoring and diagnosis. SCG waveform is observed to vary with respiration, but the mechanism of these changes is poorly understood as alterations in autonomic tone, lung volume, heart location and intrathoracic pressure are all varying during the respiratory cycle. Understanding SCG variability and its sources may help reduce variability and increase SCG clinical utility. This study investigated SCG variability during breath holding (BH) at two different lung volumes (i.e., end inspiration and end expiration) and five airway pressures (i.e., 0, ± 2-4, and ± 15-20 cm H2O). Variability during normal breathing was also studied with and without grouping SCG beats into two clusters of similar waveform morphologies (performed using the K-medoid algorithm in an unsupervised machine learning fashion). The study included 15 healthy subjects (11 Females and 4 males, Age: 21 ± 2 y) where SCG, ECG, and spirometry were simultaneously acquired. SCG waveform variability was calculated at each experimental state (i.e., lung volume and airway pressure). Results showed that breath holding was more effective in reducing the intra-state variability of SCG than clustering normal breathing data. For the BH states, the intra-state variability increased as the airway pressure deviated from zero. The subaudible-to-audible energy ratio of the BH states increased as the airway pressure decreased below zero which may be related to the effect of the intrathoracic pressure on cardiac afterload and blood ejection. When combining the BH waveforms at end inspiration and end expiration states (at the same airway pressures) into one group, the intra-state variability increased, which suggests that the lung volume and associated change in heart location were a significant source of variability. The linear trend between airway pressure and waveform changes was found to be statistically significant for BH at end expiration. To confirm these findings, more studies are needed with a larger number of airway pressure levels and larger number of subjects.

Effects of dietary fish to rapeseed oil ratio on steatosis symptoms in Atlantic salmon (Salmo salar L) of different sizes.

Choline is recognized as an essential nutrient for Atlantic salmon at all developmental stages. However, its dietary requirement is not well defined. Choline plays a critical role in lipid transport, and the clearest deficiency sign is intestinal steatosis. The present work, aiming to find whether lipid source and fish size may affect steatosis symptoms, was one of a series of studies conducted to identify which production-related conditions may influence choline requirement. Six choline-deficient diets were formulated varying in ratios of rapeseed oil to fish oil and fed to Atlantic salmon of 1.5 and 4.5 kg. After eight weeks, somatic characteristics were observed, and the severity of intestinal steatosis was assessed by histological, biochemical, and molecular analyses. Fatty acid composition in pyloric intestine, mesenteric tissue, and liver samples was also quantified. The increasing rapeseed oil level increased lipid digestibility markedly, enhancing lipid supply to the fish. Moreover, small fish consumed more feed, and consequently had a higher lipid intake. In conclusion, the results showed that choline requirement depends on dietary lipid load, which depends on the fatty acid profile as well as the fish size.

Disminución de triglicéridos sin ayuno y reducción de mortalidad por cualquier causa: un estudio de randomización mendeliana / Low nonfasting triglycerides and reduced all-cause mortality: a mendelian randomization study

Antecedentes: El aumento de los triglicéridos plasmáticos sin ayuno, marcador del aumento de colesterol en lipoproteínas remanentes, es un importante factor de riesgo para enfermedad cardiovascular, pero se desconoce si la reducción en las concentraciones de triglicéridos, sobre una base genética, a lo largo de toda la vida en última instancia conduce a una menor mortalidad por cualquier causa. Pusimos a prueba esta hipótesis. Métodos: Estudiando individuos del Copenhagen City Heart Study en un diseño de randomización mendeliana, en primer lugar estudiamos si las menores concentraciones de triglicéridos sin ayuno se asociaron con una reducción de mortalidad por cualquier causa en un análisis observacional (n=13.957); segundo, si variantes genéticas en la enzima hidrolizante de triglicéridos lipoproteína lipasa, que resultan en reducción de los triglicéridos plasmáticos sin ayuno y del colesterol de remanentes, se asociaron con una reducción de mortalidad por cualquier causa (n=10.208). Resultados...

Background: Increased nonfasting plasma triglycerides marking increased amounts of cholesterol in remnant lipoproteins are important risk factors for cardiovascular disease, but whether lifelong reduced concentrations of triglycerides on a genetic basis ultimately lead to reduced all-cause mortality is unknown. We tested this hypothesis. Methods: Using individuals from the Copenhagen City Heart Study in a mendelian randomization design, we first tested whether low concentrations of nonfasting triglycerides were associated with reduced all-cause mortality in observational analyses (n = 13 957); second, whether genetic variants in the triglyceride-degrading enzyme lipoprotein lipase, resulting in reduced nonfasting triglycerides and remnant cholesterol, were associated with reduced all-cause mortality (n = 10 208). Results...