Turbulence and Cavity Recirculation in Air-Water Skimming Flows on a Stepped Spillway

Current expertise in air-water turbulent flows on stepped chutes is limited mostly to laboratory experiments at low to moderate Reynolds numbers on chutes with flat horizontal steps. In this study, highly turbulent air-water flows skimming down a large-size stepped chute were investigated with a 1V:2.5H slope. For some experiments, the cavity recirculation was controlled using triangular vanes, or longitudinal ribs, to enhance the interactions between the skimming flow and cavity recirculating region. New experiments were performed with seven configurations. The results demonstrated the strong influence of the vanes on the cavity recirculation patterns and on the air-water flow properties. An increase in flow resistance was observed consistently with maximum rate of energy dissipation achieved with vanes placed in a zigzag pattern

PROMISE:effect of protein supplementation on fat-free mass preservation after bariatric surgery, a randomized double-blind placebo-controlled trial

Introduction: Protein malnutrition after bariatric surgery is a severe complication and leads to significant morbidity. Previous studies have shown that protein intake and physical activity are the most important factors in the preservation of fat-free mass during weight loss. Low protein intake is very common in patients undergoing bariatric surgery despite dietary counseling. Protein powder supplements might help patients to achieve the protein intake recommendations after bariatric surgery and could therefore contribute to preserve fat-free mass. This double-blind randomized placebo-controlled intervention study aims to assess the effect of a daily consumed clear protein powder shake during the first 6 months after bariatric surgery on fat-free mass loss in the first 12 months after laparoscopic Roux-en-Y gastric bypass (LRYGB). Methods and analysis:Inclusion will take place at the outpatient clinic of the bariatric expertise center for obesity of the Maasstad Hospital. Patients will be randomly assigned to either the intervention or control group before surgery. The intervention group will receive a clear protein powder shake of 200 ml containing 20 g of whey protein dissolved in water which should be taken daily during the first 6 months after LRYGB on top of their normal postoperative diet. The control group will receive an isocaloric, clear, placebo shake containing maltodextrine. Postoperative rehabilitation and physiotherapeutical guidance will be standardized and similar in both groups. Also, both groups will receive the same dietary advice from specialized dieticians. The main study parameter is the percentage of fat-free mass loss 6 months after surgery, assessed by multi-frequency bioelectrical impedance analysis (MF-BIA). Ethics and dissemination: The protocol, version 2 (February 20, 2022) has been approved by the Medical Research Ethics Committees United (MEC-U) (NL 80414.100.22). The results of this study will be submitted to peer-reviewed journals. Trial registration: ClinicalTrials.gov NCT05570474. Registered on October 5, 2022.</p

Irf4 is a positional and functional candidate gene for the control of serum IgM levels in the mouse

Natural IgM are involved in numerous immunological functions but the genetic factors that control the homeostasis of its secretion and upholding remain unknown. Prompted by the finding that C57BL/6 mice had significantly lower serum levels of IgM when compared with BALB/c mice, we performed a genome-wide screen and found that the level of serum IgM was controlled by a QTL on chromosome 13 reaching the highest level of association at marker D13Mit266 (LOD score¼3.54). This locus was named IgMSC1 and covered a region encompassing the interferon-regulatory factor 4 gene (Irf4). The number of splenic mature B cells in C57BL/6 did not differ from BALB/c mice but we found that low serum levels of IgM in C57BL/6 mice correlated with lower frequency of IgM-secreting cells in the spleen and in the peritoneal cavity. These results suggested that C57BL/6 mice have lower efficiency in late B-cell maturation, a process that is highly impaired in Irf4 knockout mice. In fact, we also found reduced Irf4 gene expression in B cells of C57BL/6 mice. Thus, we propose Irf4 as a candidate for the IgMSC1 locus, which controls IgM homeostatic levels at the level of B-cell terminal differentiation

Nominal or Real? The Impact of Regional Price Levels on Satisfaction with Life

According to economic theory, real income, i.e., nominal income adjusted for purchasing power, should be the relevant source of life satisfaction. Previous work, however, has only studied the impact of inflation adjusted nominal income and not taken into account regional differences in purchasing power. Therefore, we use a novel data set to study how regional price levels affect satisfaction with life. The data set comprises about 7 million data points that are used to construct a price level for each of the 428 administrative districts in Germany. We estimate pooled OLS and ordered probit models that include a comprehensive set of individual level, time-varying and time-invariant control variables as well as control variables that capture district heterogeneity other than the price level. Our results show that higher price levels significantly reduce life satisfaction. Furthermore, we find that a higher price level tends to induce a larger loss in life satisfaction than a corresponding decrease in nominal income. A formal test of neutrality of money, however, does not reject neutrality of money. Our results provide an argument in favor of regional indexation of government transfer payments such as social welfare benefits

Toxic metal enrichment and boating intensity: sediment records of antifoulant copper in shallow lakes of eastern England

Tributyltin (TBT), an aqueous biocide derived from antifouling paint pollution, is known to have impacted coastal marine ecosystems, and has been reported in the sediment of the Norfolk and Suffolk Broads, a network of rivers and shallow lakes in eastern England. In the marine environment, the 1987 TBT ban has resulted in expanded use of alternative biocides, raising the question of whether these products too have impacted the Broads ecosystem and freshwaters in general. Here we examine the lake sediment record in the Norfolk and Suffolk Broads for contamination by copper (Cu) (as an active biocide agent) and zinc (Zn) (as a component of booster biocides), to assess their occurrence and potential for causing environmental harm in freshwater ecosystems. We find that, after the introduction of leisure boating, there is a statistically significant difference in Cu enrichment between heavily and lightly boated sites, while no such difference exists prior to this time. At the heavily boated sites the onset of Cu enrichment coincides with a period of rapid increase in leisure boating. Such enrichment is maintained to the present day, with some evidence of continued increase. We conclude that Cu-based antifouling has measurably contaminated lakes exposed to boating, at concentrations high enough to cause ecological harm. Similar findings can be expected at other boated freshwater ecosystems elsewhere in the world

Fermilab Main Injector Beam Position Monitor Upgrade

An upgrade of the Beam Position Monitor (BPM) signal processing and data acquisition system for the Fermilab Main Injector is described. The Main Injector is a fast cycling synchrotron that accelerates protons or antiprotons from 8 to 150 GeV. Each Main Injector cycle can have a totally different magnet ramp, RF frequency configuration, beam bunch structure, and injection/extraction pattern from the previous cycle. The new BPM system provides the capabilities and flexibility required by the dynamic and complex machine operations. The system offers measurement capability in the 2.5 MHz and 53 MHz channels to detect the range of bunch structures for protons and antiprotons in both wideband (turn-by-turn) and narrowband (closed-orbit) modes. The new BPM read-out system is based on the digital receiver concept and is highly configurable, allowing the signal processing of nearly all Main Injector beam conditions, including the detection of individual batches. An overview of the BPM system in the Main Injector operating environment, some technology details and first beam measurements are presented