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l-carnitine is essential for mitochondrial β-oxidation and has been used as a lipid-lowering feed additive in humans and farmed animals. d-carnitine is an optical isomer of l-carnitine and dl-carnitine has been widely used in animal feeds. However, the functional differences between l- and d-carnitine are difficult to study because of the endogenous l-carnitine background. In the present study, we developed a low-carnitine Nile tilapia model by treating fish with a carnitine synthesis inhibitor, and used this model to investigate the functional differences between l- and d-carnitine in nutrient metabolism in fish. l- or d-carnitine (0·4 g/kg diet) was fed to the low-carnitine tilapia for 6 weeks. l-carnitine feeding increased the acyl-carnitine concentration from 3522 to 10 822 ng/g and alleviated the lipid deposition from 15·89 to 11·97 % in the liver of low-carnitine tilapia. However, as compared with l-carnitine group, d-carnitine feeding reduced the acyl-carnitine concentration from 10 822 to 5482 ng/g, and increased lipid deposition from 11·97 to 20·21 % and the mRNA expression of the genes involved in β-oxidation and detoxification in the liver. d-carnitine feeding also induced hepatic inflammation, oxidative stress and apoptosis. A metabolomic investigation further showed that d-carnitine feeding increased glycolysis, protein metabolism and activity of the tricarboxylic acid cycle and oxidative phosphorylation. Thus, l-carnitine can be physiologically utilised in fish, whereas d-carnitine is metabolised as a xenobiotic and induces lipotoxicity. d-carnitine-fed fish demonstrates increases in peroxisomal β-oxidation, glycolysis and amino acid degradation to maintain energy homeostasis. Therefore, d-carnitine is not recommended for use in farmed animals.
Although the streaked optical pyrometer (SOP) system has been widely adopted in shock temperature measurements, its reliability has always been of concern. Here, two calibrated Planckian radiators with different color temperatures were used to calibrate and verify the SOP system by comparing the two calibration standards using both multi-channel and single-channel methods. A high-color-temperature standard lamp and a multi-channel filter were specifically designed for the measurement system. To verify the reliability of the SOP system, the relative deviation between the measured data and the standard value of less than 5% was calibrated out, which demonstrates the reliability of the SOP system. Furthermore, a method to analyze the uncertainty and sensitivity of the SOP system is proposed. A series of laser-induced shock experiments were conducted at the ‘Shenguang-II’ laser facility to verify the reliability of the SOP system for temperature measurements at tens of thousands of kelvin. The measured temperature of the quartz in our experiments agreed fairly well with previous works, which serves as evidence for the reliability of the SOP system.
Altered gut microbial ecology contributes to the development of metabolic diseases including obesity. However, studies based on different populations have generated conflicting results due to diet, environment, methodologies, etc. The aim of our study was to explore the association between gut microbiota and Body Mass Index (BMI) in Chinese college students. 16S next-generation sequencing (NGS) was used to test the gut microbiota of 9 lean, 9 overweight/obesity, and 10 normal-weight male college students. The differences of gut microbiota distribution among three groups were compared, and the relationship between the richness, diversity, composition of gut microbiota and BMI were analyzed. The predominant phyla Bacteroidetes and Firmicutes were further confirmed by real-time PCR. Metagenomic biomarker discovery was conducted by Linear discriminant analysis (LDA) Effect Size (LEfSe). NGS revealed that gut microbiota composition was different among three groups, but there was no difference in the abundance ratio of Firmicutes/ Bacteroidetes. Several bacterial taxa were in linear relationship with BMI (positive relationship: uncultured bacterium (Bacteroides genus); negative relationship: Porphyromonadaceae, Acidaminococcaceae, Rikenellaceae, Desulfovibrionaceae, Blautia, Anaerotruncus, Parabacteroides, Alistipes). Moreover, gut microbiota diversity decreased with the increase of BMI. And LEfSe analyze indicated that Blautia, Anaerotruncus and its uncultured species were significantly enriched in the lean group (LDA score≥3), Parasuterella and its uncultured species were significantly enriched in the overweight/obese groups(LDA score≥3). In general, gut microbiota composition and microbial diversity were associated with BMI in Chinese male college students. Our results might enrich the understanding between gut microbiota and obesity.
The present study aimed to evaluate the effect of mandatory iodine fortification of bread on the iodine status of South Australian populations using newborn thyroid-stimulating hormone (TSH) concentration as a marker.
The study used an interrupted time-series design.
TSH data collected between 2005 and 2016 (n 211 033) were extracted from the routine newborn screening programme in South Australia for analysis. Iodine deficiency is indicated when more than 3 % of newborns have TSH > 5 mIU/l.
Newborns were classified into three groups: the pre-fortification group (those born before October 2009); the transition group (born between October 2009 and June 2010); and the post-fortification group (born after June 2010).
The percentage of newborns with TSH > 5 mIU/l was 5·1, 6·2 and 4·6 % in the pre-fortification, transition and post-fortification groups, respectively. Based on a segmented regression model, newborns in the post-fortification period had a 10 % lower risk of having TSH > 5 mIU/l than newborns in the pre-fortification group (incidence rate ratio (IRR) = 0·90; 95 % CI 0·87, 0·94), while newborns in the transitional period had a 22 % higher risk of having TSH > 5 mIU/l compared with newborns in the pre-fortification period (IRR = 1·22; 95 % CI 1·13, 1·31).
Using TSH as a marker, South Australia would be classified as mild iodine deficiency post-fortification in contrast to iodine sufficiency using median urinary iodine concentration as a population marker. Re-evaluation of the current TSH criteria to define iodine status in populations is warranted in this context.
This study compared the protective effect of sodium selenite (SS) and selenomethionine (SeMet) on heat stress (HS) invoked porcine IPEC-J2 cellular damage and integrate potential roles of corresponding selenoprotein. Cells were cultured at 37 oC until 80% conﬂuence, and then subjected to four different conditions for 24 h: at 37 oC (Control), 41.5 oC (HS), 41.5 oC supplied with 0.42 µmol Se/L SS (SS) or SeMet (SeMet). HS significantly decreased cell viability, up-regulated mRNA and protein levels of HSP70, and down-regulated mRNA and protein levels of tight junction-related proteins (CLDN-1 and ZO-1). HS induced cells injury was associated with the up-regulation (P < 0.05) of 6 inflammation-related genes and 14 selenoprotein encoding genes, and down-regulation (P < 0.05) of 2 inflammation-related genes and 5 selenoprotein encoding genes. Compared with the HS group, SS and SeMet supplementation resulted in an increase (P < 0.05) in cell viability, decreases (P < 0.05) mRNA expression of HSP70 and 6 inflammation-related genes, and rescue (P < 0.05) of mRNA and protein levels of CLDN-1 and ZO-1. SS and SeMet supplementation changes expressions of 19 selenoprotein encoding genes in cells affected by HS. Both Se supplementation significantly recovered the protein level of GPX1 and increased SELP in the IPEC-J2 cells under HS, respectively. In summary, Se supplementation alleviated the negative impact of HS on IPEC-J2 cells, and their cellular protective effect was associates with regulation expression of selenoproteins, SeMet exhibited a better protective effect.
To examine detail depth dose characteristics of ideal proton beams using the GATE Monte Carlo technique.
In this study, in order to improve simulation efficiency, we used pencil beam geometry instead of parallel broad-field geometry. Depth dose distributions for beam energies from 5 to 250 MeV in a water phantom were obtained. This study used parameters named Rpeak, R90, R80, R73, R50, full width at half maximum (FWHM), width of 80–20% distal fall-off (W(80–20)) and peak-to-entrance ratio to represent Bragg peak characteristics. The obtained energy–range relationships were fitted into third-order polynomial formulae. The present study also used the GATE Monte Carlo code to calculate the stopping power of proton pencil beams in a water cubic phantom and compared results with the National Institute of Standards and Technology (NIST) standard reference database.
The study results revealed deeper penetration, broader FWHM and distal fall-off and decreased peak-to-entrance dose ratio with increasing beam energy. Study results for monoenergetic proton beams showed that R73 can be a good indicator to characterise a range of incident beams. These also suggest FWHM is more sensitive than W(80–20) distal fall-off in finding initial energy spread. Furthermore, the difference between the obtained stopping power from simulation and NIST data almost in all energies was lower than 1%.
Detail depth dose characteristics for monoenergetic proton beams within therapeutic energy ranges were reported. These results can serve as a good reference for clinical practitioners in their daily practice.
This study investigates the acoustic and articulatory properties of phonation contrast in Shanghainese, the most thoroughly studied Chinese Wu dialect. Although previous studies generally suggest that the non-modal phonation associated with the lower register in Shanghainese is relatively breathier, it is unclear whether it is ‘breathy voice’, ‘slack voice’ or ‘whispery voice’. This study aims to provide a better understanding of the phonetic realization of the non-modal phonation in Shanghainese. Simultaneous audio and electroglottographic recordings were made from 52 speakers born before 1980. Both acoustic and articulatory data confirmed that the non-modal phonation in Shanghainese is produced with relatively less glottal constriction and more aperiodic noise than the modal phonation. The novel finding of this study is that aperiodic noise plays a much more important role than spectral measures (i.e. indicators of glottal constriction) in the phonetic realization of the non-modal phonation. This property is distinct from the breathier voices in Gujarati, White Hmong and Southern Yi. These results suggest that the non-modal phonation in Shanghainese should be characterized as ‘whispery voice’, which is phonetically distinct from both ‘breathy voice’ and ‘slack voice’.
Many components in diet have regulated oxidative stress, inflammatory reaction and even balance estrogen levels. Because these factors are closely associated with depressive symptoms in postmenopausal women, it is considered that dietary factors are able to prevent and control depressive symptoms. On the other hand, dietary pattern that considers the correlations and synergies between foods and nutrients, is expected to have a greater impact on disease risk. The aim of this study is to evaluate whether dietary patterns are associated with depressive symptoms in Chinese postmenopausal women.
A cross-sectional study of 2051 postmenopausal women (mean age: 58.8±7.4 years) was conducted in Tianjin, China. Dietary consumption was assessed by a valid self-administered food frequency questionnaire. Principal component analysis was used to derive three major dietary patterns: “healthy”, “sweets” and “Traditional Tianjin” from 88 food items. Depressive symptoms were assessed using the Zung Self-Rating Depression Scale, and cut-off point of 48 indicating serious depressive symptoms. The associations between quartile of dietary patterns and depressive symptoms were assessed by using multiple logistic regression analysis.
The multivariable-adjusted odds ratios (95% confidence intervals) of having depressive symptoms for increasing quartile of dietary patterns were as follows: “healthy”, 1.00, 0.79(0.49–1.28), 0.62(0.37–1.04), and 0.57(0.33–0.97); “sweets”,1.00, 0.75(0.42–1.3), 1.08(0.64–1.81) and 1.66(1.03–2.71); “Traditional Tianjin”, 1.00, 1.02(0.58–1.79), 0.96 (0.54–1.71) and 2.53(1.58–4.16), respectively.
The present study demonstrated that a healthy dietary pattern was inversely associated with depressive symptoms. On the contrary, greater adherence to sweets and Traditional Tianjin dietary patterns were associated with a higher prevalence of depressive symptoms.
The association of chocolate consumption with risk of gestational diabetes has not been examined. We aimed to investigate the prospective association between chocolate consumption and risk of gestational diabetes in a large birth cohort in Japan. A total of 97,454 pregnant women with a median gestational age of 12 weeks were recruited from January 2011 to March 2014. Data on demographic information, disease history, socioeconomic status, lifestyle, and dietary habits were obtained at the study enrollment. Dietary intakes during the past 12 months before study enrollment were assessed through a semi-quantitative food frequency questionnaire. The logistic regression was used to obtain the odds ratio of gestational diabetes in relation to chocolate consumption. Among 84,948 women eligible for the analysis, 1904 cases of gestational diabetes (2.2%) were identified during the period of pregnancy. After control for potential confounding factors including age, smoking status, drinking status, education level, occupation, pre-pregnant body mass index, depression, previous history of macrosomia babies, parity, physical activity, and dietary factors, women in the highest quartile of chocolate consumption, compared with those in the lowest quartile, had a significantly lower risk of developing gestational diabetes (odds ratio ½ 0.78, 95% confidence interval: 0.67-0.90; P for trend ½ 0.002). Stratified analyses suggested that the association was not significantly modified by pre-pregnancy body mass index, age, parity, smoking status, or drinking status. The present prospective cohort study provided evidence that chocolate consumption was associated with a significant lower risk of gestational diabetes in Japanese women.
In order to solve joint-angle drift problem of dual redundant manipulators at acceleration-level, an acceleration-level tri-criteria optimization motion planning (ALTC-OMP) scheme is proposed, which combines the minimum acceleration norm, repetitive motion planning, and infinity-norm acceleration minimization solutions via weighting factor. This scheme can resolve the joint-angle drift problem of dual redundant manipulators which will arise in single criteria or bi-criteria scheme. In addition, the proposed scheme considers joint-velocity joint-acceleration physical limits. The proposed scheme can not only guarantee joint-velocity and joint-acceleration within their physical limits, but also ensure that final joint-velocity and joint-acceleration are near to zero. This scheme is realized by dual redundant manipulators which consist of left and right manipulators. In order to ensure the coordinated operation of manipulators, two motion planning problems are reformulated as two general quadratic program (QP) problems and further unified into one standard QP problem, which is solved by a simplified linear-variational-inequalities-based primal-dual neural network at the acceleration-level. Computer-simulation results based on dual PUMA560 redundant manipulators further demonstrate the effectiveness and feasibility of the proposed ALTC-OMP scheme to resolve joint-angle drift problem arising in the dual redundant manipulators.
Severe phase coarsening and separation in Sn–Bi alloys have brought increasing reliability concern in microelectronic packages. In this study, a phase field model is developed to simulate the microstructural evolution and evaluate the change in macroscopic physical properties of the flip chip Cu/Sn58Bi/Cu joint under the conditions of isothermal aging, as well as the coupled loads of elastic stress and electric current stressing. Results show that large-sized Bi-rich phase particles grow up at the expense of small-sized ones. Under the coupled loads, Bi atoms migrate along the electron flow direction, consequently Bi-rich phase segregates to form a Bi-rich phase layer at the anode. The current crowding ratio in the solder decreases rapidly first and then fluctuates slightly with time. Current density and von Mises stress exhibit inhomogeneous distribution, and both of them are higher in the Sn-rich phase than in the Bi-rich phase. Electric current transfers through the Sn-rich phase and detours the Bi-rich phase. As time proceeds, the resistance of the solder joint increases, and the average von Mises stress of the solder joint decreases. The Bi-rich phase coarsens much faster under the coupled loads than under the conditions of isothermal aging.
This is a copy of the slides presented at the meeting but not formally written up for the volume.
We present a high-resolution transmission electron microscopy study, on the unit-cell scale, of the degree of tetragonality and the displacements of cations away from the centrosymmetry positions in an ultra-thin epitaxial PbZr0.2Ti0.8O3 film on a SrRuO3 electrode layer deposited on a SrTiO3 substrate. TEM results show that the lattice is highly tetragonal at the centre of the film with a c/a ratio of about 1.08, while it shows a reduced degree of tetragonality in the regions close to the interfaces. Most strikingly, we find that the maximum off-centre displacements for the central area of the film do not scale with the tetragonality in comparison with the bulk materials. The calculated switched polarization from the measured cationic displacement is 80 ìC/cm2 , and thus only half of the nominal bulk value. It is in very good agreement with electrical measurements of the switched polarization obtained via the PUND method. Furthermore, a systematic reduction of the atomic displacements is measured at the interfaces. This suggests that interface-induced suppression of the ferroelectric polarization plays a critical role in the size effect of nanoscale ferroelectrics. These issues will be discussed further in this presentation. This work was partially supported by the National Science Foundation (NSF) under Grants DMR-0132918, NSF-MRSEC DMR-0080008, and an NSF US-Europe program DMR-0244288. V.N also acknowledges the support of the Alexander von Humboldt Foundation for his stay in Germany and the financial support of an Australian Research Council Discovery Grant 0666231.
To sustainably improve cleaning of high-touch surfaces (HTSs) in acute-care hospitals using a multimodal approach to education, reduction of barriers to cleaning, and culture change for environmental services workers.
The study was conducted in 2 academic acute-care hospitals, 2 community hospitals, and an academic pediatric and women’s hospital.
Frontline environmental services workers.
A 5-module educational program, using principles of adult learning theory, was developed and presented to environmental services workers. Audience response system (ARS), videos, demonstrations, role playing, and graphics were used to illustrate concepts of and the rationale for infection prevention strategies. Topics included hand hygiene, isolation precautions, personal protective equipment (PPE), cleaning protocols, and strategies to overcome barriers. Program evaluation included ARS questions, written evaluations, and objective assessments of occupied patient room cleaning. Changes in hospital-onset C. difficile infection (CDI) and methicillin-resistant S. aureus (MRSA) bacteremia were evaluated.
On average, 357 environmental service workers participated in each module. Most (93%) rated the presentations as ‘excellent’ or ‘very good’ and agreed that they were useful (95%), reported that they were more comfortable donning/doffing PPE (91%) and performing hand hygiene (96%) and better understood the importance of disinfecting HTSs (96%) after the program. The frequency of cleaning individual HTSs in occupied rooms increased from 26% to 62% (P < .001) following the intervention. Improvement was sustained 1-year post intervention (P < .001). A significant decrease in CDI was associated with the program.
A novel program that addressed environmental services workers’ knowledge gaps, challenges, and barriers was well received and appeared to result in learning, behavior change, and sustained improvements in cleaning.
Oxidative stress is closely related to metabolic disorders, which can lead to various diseases. Nuclear factor E2-related factor 2 (Nrf2) is a central regulator of oxidative stress. Sodium butyrate (NaB) has been shown to alleviate oxidative stress and insulin resistance, yet how Nrf2 is involved in the action of NaB remains unclear. In this study, rats were rendered obese by feeding a high-fat diet for 9 weeks. NaB (300 mg/kg), which was gavaged every 2 days for 7 weeks, significantly alleviated high-fat diet-induced oxidative stress and insulin resistance. Additionally, the insulin signaling pathway in the liver was activated by NaB, associated with significant activation of Nrf2, superoxide dismutase and glutathione. Furthermore, hepatic up-regulation of Nrf2 in NaB-treated rats was associated with reduced protein content of histone deacetylase 1 and increased histone H3 acetyl K9 (H3K9Ac) modification on the Nrf2 promoter. The actions of NaB were completely abolished when Nrf2 was knocked down in vitro. Taken together, NaB acts as a histone deacetylase inhibitor to up-regulate Nrf2 expression with enhanced H3K9Ac modification on its promoter. NaB-induced Nrf2 activation stimulates transcription of downstream antioxidant enzymes, thus contributing to the amelioration of high-fat diet-induced oxidative stress and insulin resistance.
Altered heart rate variability (HRV), an index of autonomic nervous system function, has been reported in generalized anxiety disorder (GAD), but the results have been mixed. Thus, the present study, using a large sample size and better methodology, aims to examine whether GAD is associated with impaired HRV, both at rest and in response to posture challenges.
In total, 1832 participants were recruited in this study, consisting of 682 patients with GAD (including 326 drug- and comorbidity-free GAD patients) and 1150 healthy controls. Short-term HRV was measured during the supine-standing-supine test (5-min per position). Propensity score matching (PSM), a relatively novel method, was used to control for potential confounders.
After PSM algorithm, drug- and comorbidity-free GAD patients had reductions in resting (baseline) high-frequency power (HF), an index for parasympathetic modulation, and increases in the low-frequency/HF ratio (LF/HF), an index for sympathovagal balance as compared to matched controls. Furthermore, the responses of HF and LF/HF to posture changes were all attenuated when compared with matched controls. Effect sizes, given by Cohen's d, for resting HF and HF reactivity were 0.42 and 0.36–0.42, respectively.
GAD is associated with altered sympathovagal balance, characterized by attenuation in both resting vagal modulation and vagal reactivity, with an almost medium effect size (Cohen's d ≈ 0.4), regardless of medication use or comorbidity status.