233 research outputs found
European sea bass show behavioural resilience to near-future ocean acidification
Ocean acidification (OA)—caused by rising concentrations of carbon dioxide (CO₂)—is thought to be a major threat to marine ecosystems and has been shown to induce behavioural alterations in fish. Here we show behavioural resilience to near-future OA in a commercially important and migratory marine finfish, the Sea bass (Dicentrarchus labrax). Sea bass were raised from eggs at 19°C in ambient or near-future OA (1000 µatm pCO₂) conditions and n = 270 fish were observed 59–68 days post-hatch using automated tracking from video. Fish reared under ambient conditions, OA conditions, and fish reared in ambient conditions but tested in OA water showed statistically similar movement patterns, and reacted to their environment and interacted with each other in comparable ways. Thus our findings indicate behavioural resilience to near-future OA in juvenile sea bass. Moreover, simulated agent-based models indicate that our analysis methods are sensitive to subtle changes in fish behaviour. It is now important to determine whether the absences of any differences persist under more ecologically relevant circumstances and in contexts which have a more direct bearing on individual fitness
Direct current measurements of the SPIDER beam: a comparison to existing beam diagnostics
For negative ion beam sources there are several methods of measuring the
accelerated beam current, most commonly electrical measurements at the power
supply and calorimetric measurements. On SPIDER, the ITER Heating Neutral Beam
full-scale beam source prototype, electrical measurements at the acceleration
grid power supply (AGPS) are complemented by polarizing the diagnostic
calorimeter STRIKE to provide an additional electrical measurement of the
accelerated current. This is in addition to the calorimetric measurements
provided by STRIKE. These diagnostics give differing measurements of the beam
current. Exploiting the reduced number of open apertures on SPIDER a new beam
diagnostic has been installed to measure the individual beamlet currents
directly. The so called Beamlet Current Monitor (BCM) has been used to measure
the current of five beamlets during the most recent SPIDER campaign. This work
compares the BCM current to the electrical measurements at the AGPS and STRIKE.
The average BCM current agrees well with the STRIKE electrical measurements,
indicating that the AGPS overestimates the beam current. The individual
beamlets are compared to the STRIKE calorimetric measurements, showing similar
current trends with the source parameters
Lsd1 ablation triggers metabolic reprogramming of brown adipose tissue
Previous work indicated that lysine-specific demethylase 1 (Lsd1) can positively regulate the oxidative and thermogenic capacities of white and beige adipocytes. Here we investigate the role of Lsd1 in brown adipose tissue (BAT) and find that BAT- selective Lsd1 ablation induces a shift from oxidative to glycolytic metabolism. This shift is associated with downregulation of BAT-specific and upregulation of white adipose tissue (WAT)-selective gene expression. This results in the accumulation of di- and triacylglycerides and culminates in a profound whitening of BAT in aged Lsd1- deficient mice. Further studies show that Lsd1 maintains BAT properties via a dual role. It activates BAT-selective gene expression in concert with the transcription factor Nrf1 and represses WAT-selective genes through recruitment of the CoREST complex. In conclusion, our data uncover Lsd1 as a key regulator of gene expression and metabolic function in BAT
Continuous pulse advances in the negative ion source NIO1
Consorzio RFX and INFN-LNL have designed, built and operated the compact
radiofrequency negative ion source NIO1 (Negative Ion Optimization phase 1)
with the aim of studying the production and acceleration of H- ions. In
particular, NIO1 was designed to keep plasma generation and beam extraction
continuously active for several hours. Since 2020 the production of negative
ions at the plasma grid (the first grid of the acceleration system) has been
enhanced by a Cs layer, deposited though active Cs evaporation in the source
volume. For the negative ion sources applied to fusion neutral beam injectors,
it is essential to keep the beam current and the fraction of co-extracted
electrons stable for at least 1 h, against the consequences of Cs sputtering
and redistribution operated by the plasma. The paper presents the latest
results of the NIO1 source, in terms of caesiation process and beam
performances during continuous (6{\div}7 h) plasma pulses. Due to the small
dimensions of the NIO1 source (20 x (diam.)10 cm), the Cs density in the volume
is high (10^15 \div 10^16 m^-3) and dominated by plasma-wall interaction. The
maximum beam current density and minimum fraction of co-extracted electrons
were respectively about 30 A/m^2 and 2. Similarly to what done in other
negative ion sources, the plasma grid temperature in NIO1 was raised for the
first time, up to 80 {\deg}C, although this led to a minimal improvement of the
beam current and to an increase of the co-extracted electron current.Comment: 11 pages, 7 figures. Contributed paper for the 8th International
symposium on Negative Ions, Beams and Sources - NIBS'22. Revision 1 of the
preprint under evaluation at Journal of Instrumentation (JINST
Oral dosing of rodents using a palatable tablet
Rationale: Delivering orally bioavailable drugs to rodents is an important component to investigating that route of administration in novel treatments for humans. However, the traditional method of oral gavage requires training, is stressful, and can induce oesophageal damage in rodents. Objectives: To demonstrate a novel administrative technique – palatable gelatine tablets – as a stress-free route of oral delivery. Methods: 24 male Lister hooded rats were sacrificed for brain tissue analysis at varying time-points after jelly administration of 30 mg/kg of the wake-promoting drug modafinil. A second group of 22 female rats were tested on locomotor activity after 30 mg/kg modafinil, or after vehicle jellies, with the locomotor data compared to the brain tissue concentrations at the corresponding times. Results: Modafinil was present in the brain tissue at all time-points, reducing in concentration over time. The pattern of brain tissue modafinil concentration is comparable to previously reported results following oral gavage. Modafinil-treated rats were more active than control rats, with greater activity during the later time-periods – similar to that previously reported following intraperitoneal injection of 40 mg/kg modafinil. Conclusions: Palatable jelly tablets are an effective route of administration of thermally-stable orally-bioavailable compounds, eliminating the stress/discomfort and health risk of oral gavage and presenting as an alternative to previously reported palatable routes of administration where high protein and fat levels may adversely affect appetite for food reward, and uptake rate in the gastrointestinal tract.Publisher PDFPeer reviewe
The histone code reader Spin1 controls skeletal muscle development
While several studies correlated increased expression of the histone code reader Spin1 with tumor formation or growth, little is known about physiological functions of the protein. We generated Spin1(M5) mice with ablation of Spin1 in myoblast precursors using the Myf5-Cre deleter strain. Most Spin1(M5) mice die shortly after birth displaying severe sarcomere disorganization and necrosis. Surviving Spin1(M5) mice are growth-retarded and exhibit the most prominent defects in soleus, tibialis anterior, and diaphragm muscle. Transcriptome analyses of limb muscle at embryonic day (E) 15.5, E16.5, and at three weeks of age provided evidence for aberrant fetal myogenesis and identified deregulated skeletal muscle (SkM) functional networks. Determination of genome-wide chromatin occupancy in primary myoblast revealed direct Spin1 target genes and suggested that deregulated basic helix-loop-helix transcription factor networks account for developmental defects in Spin1(M5) fetuses. Furthermore, correlating histological and transcriptome analyses, we show that aberrant expression of titin-associated proteins, abnormal glycogen metabolism, and neuromuscular junction defects contribute to SkM pathology in Spin1(M5) mice. Together, we describe the first example of a histone code reader controlling SkM development in mice, which hints at Spin1 as a potential player in human SkM disease
MRI of Arterial Flow Reserve in Patients with Intermittent Claudication: Feasibility and Initial Experience
Objectives: The aim of this work was to develop a MRI method to determine arterial flow reserve in patients with intermittent claudication and to investigate whether this method can discriminate between patients and healthy control subjects. Methods: Ten consecutive patients with intermittent claudication and 10 healthy control subjects were included. All subjects underwent vector cardiography triggered quantitative 2D cine MR phase-contrast imaging to obtain flow waveforms of the popliteal artery at rest and during reactive hyperemia. Resting flow, maximum hyperemic flow and absolute flow reserve were determined and compared between the two groups by two independent MRI readers. Also, interreader reproducibility of flow measures was reported. Results: Resting flow was lower in patients compared to controls (4.961.6 and 11.163.2 mL/s in patients and controls, respectively (p,0.01)). Maximum hyperemic flow was 7.362.9 and 16.463.2 mL/s (p,0.01) and the absolute flow reserve was 2.461.6 and 5.361.3 mL/s (p,0.01), respectively in patients and controls. The interreader coefficient of variation was below 10 % for all measures in both patients and controls. Conclusions: Quantitative 2D MR cine phase-contrast imaging is a promising method to determine flow reserve measures in patients with peripheral arterial disease and can be helpful to discriminate patients with intermittent claudication fro
国际化十年:一家澳大利亚零售银行的经验之谈
上个世纪最后四十年见证了国际银行业务和跨国银行业务显著增长的历程。推动这一发展的力量包括全球化、解除管制以及信息技术的发展。在19世纪及20世纪初发生的第一次现代意义上的跨国银行业务发展浪潮中,那些来自殖民宗主国的银行领导了时代潮流。而在最近的这次跨国银行业务扩张中,美国的金融机构占据了领导地位,这是与第一次明显不同的。因此,许多学术文章都着重研究美国的银行,包括他们的动机、经营战略以及国际化经验。此外,与银行业国际化的第一阶段相比,此次银行业的国际化扩张更大程度地突出了批发和机构银行业务,而不是零售银行业务(除了少数例外)。这一特点在近年来对跨国银行经营的学术研究中也体现得十分明显[ 有关调查,见Bain,et al (2001)。]。译者单位:厦门大学经济学院国际经济与贸易系(361005
In Vivo Methods for the Assessment of Topical Drug Bioavailability
This paper reviews some current methods for the in vivo assessment of local cutaneous bioavailability in humans after topical drug application. After an introduction discussing the importance of local drug bioavailability assessment and the limitations of model-based predictions, the focus turns to the relevance of experimental studies. The available techniques are then reviewed in detail, with particular emphasis on the tape stripping and microdialysis methodologies. Other less developed techniques, including the skin biopsy, suction blister, follicle removal and confocal Raman spectroscopy techniques are also described
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