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In a compact multi-radiation imaging system, the substitution of traditional charge-coupled devices with a plastic scintillators array coupled with silicon photomultiplier detectors significantly enhances the radiation tolerance of the detection and imaging module, thereby reducing the system footprint. We present a detailed structure of a compact fast neutron/gamma-ray dual-modality imaging system based on a plastic scintillators array and evaluate its performance in imaging various samples. The detector array consists of nine 14.7 × 14.7 × 100 mm3 EJ-276 plastic scintillators coupled with corresponding silicon photomultiplier units, arranged in a 3 × 3 grid. The usage of EJ-276 plastic scintillators allows for discrimination between neutron and gamma signals through pulse shape discrimination techniques, enabling data separation between neutrons and gamma rays. In this paper, we present the experimental procedure and results of fast neutron-gamma imaging for objects containing aluminum and polyethylene materials. Fast neutrons and gammas are delivered by an Cf-252 source. The experimental results demonstrate that the system achieves dual-modality grayscale imaging and has resolution for sample thickness. Reconstructed image contrast allows qualitative differentiation of sample materials, especially detecting low-Z materials encapsulated by high-Z materials. [ABSTRACT FROM AUTHOR]

The competition between α -decay and spontaneous fission (SF) of Z = 112 isotopes are studied. The α -decay half-lives are estimated by the generalized liquid-drop model (GLDM) and several sets of analytic formulas. These formulas include the Royer formula, Viola–Seaborg semiempirical (VSS) formula and universal decay law (UDL). For the SF, its half-lives are calculated by using the Xu, Ren, Karpov and Santhosh formulas. It is shown that the predicted α -decay half-lives by different approaches are more or less identical. However, the SF half-lives are highly sensitive to models. To test the accuracies of different SF formulas, the half-lives of 56 even–even heavy nuclei are calculated by these formulas. By comparing with the experimental data, it is found that the Xu formula is the most accurate one to reproduce the experimental SF half-lives. This allows us to make a systematic prediction on the competition between α -decay and SF of even–even superheavy nuclei (SHN) with Z = 104 – 120 by using the Xu formula and the above mentioned models on α -decay. The calculations suggest that 258,260 104, 268 – 276 110, 270 – 280 112, 272 – 286 114, 274 – 294 116, 284 – 302 118 and 292 – 308 120 have smaller α -decay half-lives than those of SF. Thus these nuclei can be synthesized and identified via α -decay in the laboratory. In addition, it is observed that N = 162 , 178, 184 and 196 may be the submagic or magic numbers. Finally, an extensive study on the possible α -decay chains for Z = 120 isotopes is performed. It is predicted that six sequential α -decay chains can be observed from 292 – 296 120, four α -decay chains from 298 120, three α -decay chains from 300,302 120, two α -decay chains from 304,306 120, and only one α -decay chain from 308 120. These nuclei are the most likely candidates to be synthesized experimentally via α -decay in the near future. [ABSTRACT FROM AUTHOR]

0.94(Na 0.5 Bi 0.5 TiO 3 )-0.06BaTiO 3 ferroelectric thin films with and without the Pb 0.8 La 0.1 Ca 0.1 Ti 0.975 O 3 seed layer were deposited on platinum-buffered silicon substrates by using Sol–Gel process. The influence of Pb 0.8 La 0.1 Ca 0.1 Ti 0.975 O 3 seed layer and annealing temperatures on the microstructures, ferroelectric properties and energy-storage performances of the as-prepared films were investigated in details. The low annealing temperature and Pb 0.8 La 0.1 Ca 0.1 Ti 0.975 O 3 seed layer could improve the values of electric break-down field strength and P max - P r , which play a vital role for high recoverable energy-storage density. Owing to the high electric break-down field strength value of 3310 kV/cm, a large recoverable energy density of W =17.2 J/cm 3 and a high energy efficiency of η =74.3% were obtained for the 0.94(Na 0.5 Bi 0.5 TiO 3 )-0.06BaTiO 3 thin film with the Pb 0.8 La 0.1 Ca 0.1 Ti 0.975 O 3 seed layer, which was annealed at 450 °C. [ABSTRACT FROM AUTHOR]

The recombination dynamics of singlet and triplet oppositely charged polarons under the influence of electron–electron (e–e) interactions in coupled polymer chains are investigated using a multi-configurational time-dependent Hartree–Fock (MCTDHF) method. During recombination processes, singlet and triplet intrachain excitons are important products. By calculating the yields of the singlet and triplet intrachain excitons as a function of the on-site and long-range e–e interactions, it is found that the yields of the singlet and triplet intrachain excitons both decrease with increasing on-site e–e interactions. On the other hand, as the long-range e–e interactions increase, the yields of singlet intrachain excitons initially increase and then maintain a constant value, while the yields of the triplet intrachain excitons decrease. Our results show that the long-range e–e interaction is of fundamental importance and improves the luminescence efficiency in coupled polymer chains. Finally, the influence of the polymer chain length on the yields of singlet and triplet intrachain excitons is discussed. [ABSTRACT FROM AUTHOR]

This paper presents the inverse magnetocaloric effect associated with martensitic transformation in a polycrystalline Ni 50 Co 2 Mn 33 In 15 alloy. Through the structural measurements, it is found that the bulk sample have a well-developed preferred orientation. The isothermal entropy change ( Δ S T ) has been calculated by changes of volume fractions at certain temperature based on Clausius–Clapeyron equation for different magnetic fields. The maximum Δ S T of Ni 50 Co 2 Mn 33 In 15 reaches 21.5 J/kg K and keeps in the relative broad temperature range, leading to a great refrigerant capacity under a moderate magnetic field. This can be ascribed to the fact that present textured alloy shows a large shifts in the transition equilibrium temperature with magnetic field as well as a narrow transformation width. [ABSTRACT FROM AUTHOR]

A fast and automatic method for radiocarbon analysis of aerosol samples is presented. This type of analysis requires high number of sample measurements of low carbon masses, but accepts precisions lower than for carbon dating analysis. The method is based on online Trapping CO 2 and coupling an elemental analyzer with a MICADAS AMS by means of a gas interface. It gives similar results to a previously validated reference method for the same set of samples. This method is fast and automatic and typically provides uncertainties of 1.5–5% for representative aerosol samples. It proves to be robust and reliable and allows for overnight and unattended measurements. A constant and cross contamination correction is included, which indicates a constant contamination of 1.4 ± 0.2 μg C with 70 ± 7 pMC and a cross contamination of (0.2 ± 0.1)% from the previous sample. A Real-time online coupling version of the method was also investigated. It shows promising results for standard materials with slightly higher uncertainties than the Trapping online approach. [ABSTRACT FROM AUTHOR]

Low extracellular enzyme activity in desert soil can be recovered during the succession of re-vegetation, especially in soils forming under shrubs (microsite soil), which closely reflects desert restoration conditions. However, not much is known about the restoration of soil enzyme activity at these microsites. By using the space-for-time substitution method, soils on moving sand dunes that had been stabilized at different dates over a fifty year period at the southeastern fringe of the Tengger Desert were selected to investigate the enzyme activities in the surface soil crust and three other soil depths at microsites to demonstrate the evolution of enzymatic activity at different stages from bare soil to complex vegetation over a fifty year sequence. The results showed that organic C and total and available N, P, and enzyme activities (dehydrogenase, catalase, α- and β-glucosidase, protease, and phosphatase) were progressively enhanced in each microsite soil in the 50-year chronosequence and had effect down to 35 cm depth. Soil enzyme activities of the crust and the 0–5 cm soil layer were higher than in deeper soil layers. The observed increase over time of the values of the measured soil properties, such as organic C, total and available N, was much larger in the crust and the 0–5 cm soil layer in comparison to the deeper layers. The improvement of desert soil quality indicated that desertification can be mitigated to a certain extent under human controls. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effects of 2-methylbutyrate supplementation on rumen microflora, enzyme activities and methane production in Simmental steers consuming a diet consisting of 600 g/kg corn stover and 400 g/kg concentrate (dry matter [DM] basis). Eight ruminally cannulated Simmental steers were used in a replicated 4 × 4 Latin square design. The treatments were: control (without 2-methylbutyrate), low 2-methylbutyrate (LMB), medium 2-methylbutyrate (MMB) and high 2-methylbutyrate (HMB) with 0, 8.4, 16.8 and 25.2 g 2-methylbutyrate per steer and per day, respectively. Dry matter intake (averaged 9 kg/day) was restricted to a maximum of 0.9 of ad libitum intake. Whether direct counts, roll-tube technique or real-time PCR quantification were used, populations of total bacteria, cellulolytic bacteria and anaerobic fungi linearly increased (P<0.04) and were higher (P<0.05) for MMB and HMB than for control and LMB, whereas those of protozoa and total methanogens linearly reduced and were lower for MMB and HMB than for control and LMB. With increasing 2-methylbutyrate supplementation, real-time PCR quantification of populations of Ruminococcus albus , Ruminococcus flavefaciens , Bufyrivibrio fibrisolvens and Fibrobacter succinogenes linearly increased (P<0.05) and was higher for MMB and HMB than for control (P<0.05). Activities of CMCase, xylanase and β-glucosidase linearly increased (P<0.05) and were higher (P<0.05) for MMB and HMB than for control and LMB, whereas that of protease linearly reduced (P<0.05) and was lower for MMB and HMB than for control and LMB (P<0.05). Activities of α-amylase and α-glucosidase tended to be higher (P<0.08) for MMB and HMB than for control and LMB, but activity of urease tended to be lower for MMB and HMB than for control and LMB. Methane production linearly decreased (P<0.01) and was lower for MMB and HMB than for control (P<0.05) with increasing 2-methylbutyrate supplementation. Effective degradabilities of cellulose and hemicellulose of corn stover linearly increased (P<0.01) and were higher for MMB and HMB than for control (P<0.05), whereas that of crude protein in concentrate linearly decreased (P<0.01) and was lower for MMB and HMB than for control and LMB (P<0.05) with increasing 2-methylbutyrate supplementation. The present results indicate that supplementation of diet with 2-methylbutyrate altered ruminal microbial populations and improved ruminal enzyme activities in a dose-dependent manner in steers fed high-roughage diet. In the experimental conditions of this trial, the optimum daily dose of 2-methylbutyrate at 16.8 g per steer is suggested. [ABSTRACT FROM AUTHOR]

A series of Mn-doped BiFeO 3 (BFO) thin films were prepared on Pt/Ti/SiO 2 /Si(111) substrates using a chemical solution deposition method. The structural and optical properties of the Mn doped BFO thin films were studied by X-ray diffraction, Raman spectroscopy and ellipsometric spectroscopy. The X-ray diffraction analysis shows that the films have a single perovskite structure and that a phase transition appears with increasing of the Mn content. The Raman scattering spectra reveal that there are two additional peaks at around 480 and 620 cm − 1 for the Mn-doped BFO samples comparing to the undoped one, indicating the existence of orthorhombic phase. Ellipsometric spectroscopy measurements were carried out in the spectral range of 1–5 eV and the experimental data fitted based on the Tauc–Lorentz model using two oscillators. The optical constants (refractive index n and extinction coefficients k) of the Mn-doped BFO thin films were determined. Moreover, the band gap was found to decrease with increasing of the Mn content. [ABSTRACT FROM AUTHOR]

Epitaxial (Ba 0.39 Sr 0.61 ) 6 Ti 2 Nb 8 O 30 (BSTN) thin films have been prepared on MgO (001) substrates by pulsed laser deposition technique. Their structural qualities and surface morphology were studied by X-ray diffraction (XRD) and scanning electron microscopy. XRD indicates that single crystalline BSTN layers with (001) orientation perpendicular to the substrate plane were obtained. Optical studies by ellipsometric and optical transmittance spectra measurements were carried out. The optical constants (refractive index n and extinction coefficient k) of the BSTN film have been determined. [ABSTRACT FROM AUTHOR]

The non-stoichiometric Zr 0.9 Ti x V 2 ( x = 0, 0.2, 0.3, 0.4) alloys are designed to explore the effect of non-stoichiometry on phase constituent, microstructure and hydrogenation properties of Zr-based AB 2 Laves alloys. The alloys are prepared by non-consumable arc melting and annealed at 1273 K for 168 h in argon atmosphere to ensure the homogeneity. Phase structure investigation shows the α-Zr/β-Zr phase and V-BCC phase originating from the non-equilibrium solidification can be reduced after annealing, C15-type ZrV 2 becomes the dominant phase. Meanwhile, a small amount of Zr 3 V 3 O phase generates when x ≤ 0.2 and the β-Zr transforms to α-Zr when x > 0.2. High density annealing twins are observed in ZrV 2 matrix by TEM. Activation behavior, hydrogenation kinetics and PCT characteristics of annealed Zr 0.9 Ti x V 2 are investigated in the temperature range 673–823 K. With the decrease in B/A ratio or increase in Ti content, the initial hydrogen absorption speed decreases obviously, the plateaus of PCT curves become wide and flat, meanwhile the hydrogen absorption capacity and the stability of metal hydrides increases. Twin defects observed in these alloys play an important role in accelerating the hydrogenation kinetics. In addition, phase constituent after hydrogenation is analyzed. [ABSTRACT FROM AUTHOR]

The formation and evolution of photogenerated soliton pairs in trans -polyacetylene is simulated by using a nonadiabatic dynamical method. Electron–lattice interaction as well as electron correlation effects are both included by employing the Su–Schrieffer–Heeger+Pariser–Parr–Pople model. We adopt the multiconfigurational time-dependent Hartree–Fock formulas which allows for the distinguishing between charged and neutral soliton pairs. It is found that charged soliton pairs are created in the initial stage of the evolution after photoexcitation. Subsequently, the formed charged soliton pairs transform into neutral ones during the dynamical evolutions. The conversion time from charged to neutral state depends on the strength of Coulomb interactions. However, neutral soliton pairs are suppressed in the non-interacting limit, which is in good agreement with the previous estimates based on the Su–Schrieffer–Heeger model. We hope these results can provide further insight into some of the basic issues of interest in photogenerated processes in conducting polymers. • We have studied the formation and evolution of photogenerated soliton pairs • Charged soliton pairs are created in the initial stage after the photoexcitation. • Charged pairs transform into neutral ones if e–e correlations are considered. • Neutral pairs are suppressed in the non-interacting limit. • e–e interactions are the key ingredient in driving the formation of neutral pairs. [ABSTRACT FROM AUTHOR]

• Geometric characteristics of actual micro scratch are studied and measured. • Two principles to deal with fatigue damage problem caused by micro scratch is proposed. • area Δ is proposed to describe fatigue damage quantitatively for micro scratch. • Combined with area Δ and Paris law, fatigue life model based on micro scratch is established. Micro scratch with depth and width of micron expresses a significant influence on fatigue life. However, little literature is available on modelling the effect of micro scratch on the fatigue life of TC17 titanium alloy. In this paper, the geometric characteristics of micro scratch, especially depth and width, were obsevered and measured. Then, fatigue experiment was conducted to obtain the corresponding fatigue test data. Result shows the presence of micro scratches dramatically reduced the fatigue life from very high cycle fatigue (VHCF) to the high cycle fatigue (HCF) regime. According to the geometrical characteristics of micro scratch, two principles of no obvious influence of scratch direction and length on fatigue life was proposed based on Murakami theory. A new parameter area Δ is proposed to describe fatigue damage quantitatively caused by micro scratches, which is defined as the square root of triangle area of scratch section. An HCF life model of TC17 with the consideration of micro scratches is established by the combined application of area Δ and Paris formula. The validity of the model is confirmed by a good agreement between predicted and experimental results. [ABSTRACT FROM AUTHOR]

In view of poor oxidation resistance of Ti6Al4V, the composites coatings prepared by laser cladding were used to solve the above shortcoming with a mixture of NiCrBSi and 5 wt%- 30 wt% Si as the cladding material. The investigation into the evolution in microstructure, mechanical properties and oxidation resistance with the Si content was carried out in detail. The results indicated that the coating with a Si content of 5 wt% was mainly composed of Ti 2 Ni, TiNi, TiB 2 , TiB and TiC. A new phase of Ti 5 Si 3 was synthesized in the coatings with a Si content more than 10 wt%, and its content presented an upward tendency with the Si content coupled with the decrease in TiB 2 , TiB and TiNi. The microstructural change caused the slight increase (about 3.82%) in microhardness of the coatings, accompanied with which their fracture toughness was correspondingly reduced by about 23.90%. The increase in Si content significantly improved oxidation resistance of the coatings due to the reduction in oxidation weight gain. The oxidation weight gain of the coatings was reduced about 36.98% when the Si content was increased from 5 wt% to 30 wt%. A compacter oxidation layer could be formed on the coating's surface with a higher Si content due to the higher PBR (Pilling-Bedworth ratio)value for Ti 5 Si 3 subject to oxidation than those of the other phases, which played the essential role in the improvement in the coatings' oxidation resistance. The suitable addition of Si was confirmed as 20 wt%, in which the coating was endowed with excellent comprehensive mechanical properties and outstanding oxidation resistance. • A laser-clad coating with outstanding oxidation resistance was produced on Ti6Al4V. • The coating also exhibited good mechanical property (hardness and toughness). • Microstructural evolution with increasing Si content in cladding material was explored. • Changes in mechanical property resulting from microstructural evolution were studied. • The oxidation mechanism of the coatings with the Si content was revealed in details. [ABSTRACT FROM AUTHOR]

The main purpose of this investigation was to identify microstructure and cyclic deformation behavior of a 3D-printed Ti–6Al–4V alloy via selective electron beam melting (SEBM). Abundant orientated α-lamellae were present in the prior columnar β grains along the building direction. Four distinct high-angle α/α grain boundaries were detected as stipulated by the Burgers orientation relationship in the β→α phase transformation at a relatively slow cooling rate during SEBM, including the unique low-energy prismatic/basal (PB) grain boundaries with a misorientation angle of 90° in the 3D-printed Ti–6Al–4V alloy. The alloy exhibited superior strength and adequate ductility, along with a certain extent of strain-rate sensitivity. Cyclic stabilization largely sustained, while cyclic softening occurred at higher strain amplitudes. Although fatigue life could be described by Smith, Watson and Topper (SWT) model, it would be better predicted via a total strain energy-based model. Crack initiation occurred from near-surface defects of entrapped gas pores or residual unmelted zones, and crack propagation was characterized by typical fatigue striations. The results obtained would help promote the safe and reliable applications of 3D-printed titanium components. Image 1 • A superior strength along with sufficient ductility is achieved via 3D printing. • Abundant α lamellae are present and positioned in the prior columnar β grains. • Distinct α/α grain boundaries are detected in the β.→α phase transformation. • Cyclic stabilization retains despite cyclic softening at higher strain amplitudes. • Fatigue life can be well predicted via a total strain energy-based approach. [ABSTRACT FROM AUTHOR]

The manganese based lithium ion sieve H 1.6 Mn 1.6 O 4 is regarded as a promising adsorbent for recovering lithium from salt-lake brines. However, the poor recycle stability caused by the dissolution of manganese hinders its industrial application. In this work, the Co-doped H 1.6 Co x Mn 1.6-x O 4 ion sieve with enhanced cycling performance for Li + adsorption was prepared through hydrothermal synthesis. The results of XRD and SEM indicated that Co-doping did not affect the spinel crystal structure of Li 1.6 Mn 1.6 O 4 and a micro array structure was obtained. The cooperative effect of Co-doping and the micro array structure morphology on the Li + adsorption performance was investigated. Compared with H 1.6 Mn 1.6 O 4 (23.53 mg/g), the adsorption capacity of H 1.6 Co 0.16 Mn 1.44 O 4 reached 29.95 mg/g. Also, H 1.6 Co 0.16 Mn 1.44 O 4 showed excellent cycling performance that the Li + adsorption capacity maintained over 88% and the dissolution rate of manganese was below 2% after five cycles. The Co-doped H 1.6 Co x Mn 1.6-x O 4 ion sieves show the prospects to be employed for the Li + extraction from aqueous lithium resources. [ABSTRACT FROM AUTHOR]

To be effective, the concentration of antibiotic used must exceed the minimum inhibitory concentration (MIC) against infecting organisms at and in the surgical site. Few studies follow antibiotic levels for tissues that are manipulated during surgery. The aim of this work was to develop and validate a novel LC-MS method as well as an efficient extraction technique for the quantification of cefazolin in local tissues and whole blood. This method uses the same efficient extraction method across multiple tissue types affected by orthopedic surgery: blood, fat, synovium, and bone marrow. The ability to quantify cefazolin in these tissues will help identify surgical techniques and antibiotic dosing protocols that better protect patients from infection. The internal standard, 13C 2 ,15N-cefazolin, co-elutes with cefazolin, and was used in calibration curves and tissue extracts as well as for cefazolin recovery and matrix effects. The protocol was rigorously tested, including measurements of reproducibility and calibration curve quality. The recovery of the extraction method ranges from 94% to 113% across all sample types. There is little to no matrix effect on cefazolin signal (98–120%). The developed method was used to determine cefazolin concentrations in tissues of 10 patients undergoing a total knee replacement. Cefazolin blood concentrations were approximately 500 times higher than in adipose, synovium, and bone marrow tissues. This clinical data shows that although the minimum inhibitory concentration is largely surpassed in blood, the concentration of cefazolin in fat, synovium, and bone marrow could be insufficient during a knee replacement. This method of cefazolin quantification will help surgeons optimize antibiotic concentrations in the local tissues during knee replacement surgery and potentially reduce serious post-surgical infections. • Quantitation of cefazolin in exposed tissues during total knee replacement using LC-MS/MS. • One Extraction method for multiple tissues with recovery ranging from 94% to 113%. • Quantitation method with high accuracy and precision for multiple biological matrices. • Comparison of cefazolin levels in patient tissues recovered at different time points during total knee replacement surgery. [ABSTRACT FROM AUTHOR]

Inspired by the high performance of rotary and insect flapping wings capable of vertical take-off and landing and hovering (VTOLH), a novel flapping wing rotor (FWR) has been developed by combining the above two types of wing motions. The FWR offers an alternative configuration for micro air vehicles (MAV) of such high flight performance. Unlike the well-studied aerodynamics of rotary and insect-like flapping wing with prescribed wing motion, the aerodynamic lift and efficiency of the FWR associated with optimal kinematics of motion has not been studied in a systematic manner before. This investigation is therefore focused on the FWR optimal kinematic motion in terms of aerodynamic lift and efficiency. Aerodynamic analysis is conducted for a FWR model of aspect ratio 3.6 and wing span 200 mm in a range of kinematic parameters. The analysis is based on a quasi-steady aerodynamic model with empirical coefficients and validated by CFD results at Re ∼ 3500 . For comparison purpose, the analysis includes rotary and insect-like flapping wings in hovering status with the FWR at an equilibrium rotation speed when the thrust equals to drag. The results show that the rotary wing has the greatest power efficiency but the smallest lift coefficient. Whereas the FWR can produce the greatest aerodynamic lift with power efficiency between rotary and insect-like flapping wings. The results provide a quantified guidance for design option of the three types of high performance MAVs together with the optimal kinematics of motion according to flight performance requirement. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to analyze brain functional connectivity and its relationship to cognition in patients with mild traumatic brain injury (mTBI). Methods: Twenty-five patients with mTBI and 25 healthy control subjects were studied using resting-state functional MRI (rs-fMRI). Amplitudes of low-frequency fluctuations (ALFFs) and functional connectivity (FC) were calculated and correlated with cognition. Results: Compared with the normal control group, the mTBI patients showed a significant decrease in working memory index (WMI) and processing speed index (PSI), as well as significantly decreased ALFFs in the cingulate gyrus, the middle frontal gyrus and superior frontal gyrus. In contrast, the mTBI patients' ALFFs in the left middle occipital gyrus, the left precuneus, and lingual gyrus increased. Additionally, FC significantly decreased in the thalamus, caudate nucleus, and right hippocampus in the mTBI patients. Statistical analysis further showed a significant positive correlation between the ALFF in the cingulate gyrus and the WMI ( R = 0.423, P < 0.05) and a significant positive correlation between the FC in the left thalamus and left middle frontal gyrus and the WMI ( R = 0.381, P < 0.05). Conclusion: rs-fMRI can reveal the functional state of the brain in patients with mTBI. This finding differed from observations of the normal control group and was significantly associated with clinical cognitive dysfunction. Therefore, rs-fMRI offers an objective imaging modality for treatment planning and prognosis assessment in patients with mTBI. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effects of 2-methylbutyrate supplementation on growth performance and rumen development in pre- and post-weaned dairy calves. Fifty-six Chinese Holstein male calves with 15 days of age and 46.5 ± 0.37 kg of body weight (BW) were randomly assigned to one of four groups. The treatments were: control, low-2-methylbutyrate (LMB), moderate-2-methylbutyrate (MMB) and high-2-methylbutyrate (HMB) with 0, 3, 6 and 9 g 2-methylbutyrate per calf per day, respectively. Supplemental 2-methylbutyrate was hand- mixed into milk in pre-weaned calves and the concentrate portion of post-weaned calves. The study lasted 75 days, including a 15-day adaptation period and followed by a 60-day sampling period. Calves were weaned at 60 days of age. Six calves were chosen from each treatment at random and slaughtered at 30 and 90 days of age. Body weight, dry matter (DM) intake and stomach weight were measured, samples of ruminal tissues and blood were determined. DM intake increased linearly (P < 0.03) for post-weaned calves and overall DM intake with increasing 2-methylbutyrate supplementation and was higher for MMB and HMB than for LMB and control (P < 0.05). Average daily gain (ADG) increased linearly (P < 0.05) for pre-weaned calves, post-weaned calves and overall ADG with increasing 2-methylbutyrate supplementation, and was higher for MMB and HMB than for LMB and control (P < 0.05). Total stomach weight for pre- and post-weaned calves increased linearly (P < 0.05) and was higher for MMB and HMB than for LMB and control (P < 0.05). The ratio of rumen weight to total stomach weight tended to increase linearly (P = 0.055) for pre-weaned calves and increased linearly (P = 0.019) for post-weaned calves, whereas the ratio of abomasum weight to total stomach weight decreased linearly (P < 0.05) for pre-weaned calves and post-weaned calves with increasing 2-methylbutyrate supplementation. The ratio of total stomach weight to body weight for pre-weaned calves and post-weaned calves increased linearly (P < 0.05) and was higher for MMB and HMB than for LMB and control (P < 0.05). Both the length and width of rumen papillae, and the relative expression of mRNA for growth hormone receptor (GHR) and 3-hydroxy-3-methylglutaryl-CoA synthase 1 (HMGCS1) in rumen mucosa tended to increase linearly for pre-weaned calves, but increased linearly (P < 0.05) for post-weaned calves and was higher for MMB and HMB than for LMB and control (P < 0.05). Blood concentrations of BHBA increased linearly (P < 0.05) for post-weaned calves with increasing 2-methylbutyrate supplementation and was higher for MMB and HMB than for LMB and control (P < 0.05). Blood concentrations of GH and IGF-1 increased linearly (P < 0.05) for pre- and post-weaned calves with increasing 2-methylbutyrate supplementation and was higher for MMB and HMB than for LMB and control (P < 0.05). The present results indicated that 2-methylbutyrate accelerated growth of calves by improving rumen development and its ketogenesis. The 2-methylbutyrate stimulates the growth performance and rumen development of dairy calves in a dose-dependent manner. In the experimental conditions of this trial, the optimum 2-methylbutyrate dose was about 6.0 g 2-methylbutyrate per calf per day. [ABSTRACT FROM AUTHOR]

Combining the Su–Schrieffer–Heeger and Pariser–Parr–Pople model (SSH+PPP), we have studied the influence of electron–electron interactions on the motion and dissociation of a polaron in the presence of an electric field, with emphasis on the long-range Coulomb interactions. The multiconfigurational time-dependent Hartree–Fock (MCTDHF) formalism was used to compute the electron–electron interactions. How the saturated velocity and the critical dissociation electric field of the polaron are related to the on-site Coulomb repulsion and long-range Coulomb interactions has been investigated. It was found that the on-site Coulomb interaction does not favor the motion of a polaron. There is a critical strength of the long-range Coulomb interaction for which the polaron takes on the most localized configuration. Comparing with the results obtained using the extended Hubbard model, we found that competition between the long-range Coulomb interactions and the on-site Coulomb interaction leads to a non-monotonic dependence of both the saturated velocity and the critical dissociation electric field on the long-range Coulomb interactions. [ABSTRACT FROM AUTHOR]

Abstract: In this work, a comprehensive model is established to predict the surface roughness achieved by single point diamond turning. In addition to the calculation of the roughness components in relation to the kinematics and minimum undeformed chip thickness, the newly developed model also takes the effects of plastic side flow and elastic recovery of materials as machined into account. Moreover, the ‘size effect’ has also been successfully integrated into the model, i.e. an inflection point appears in the trend line of predicted surface roughness as the ratio of maximal undeformed chip thickness to cutting edge radius (h Dmax/r n) is equal to one unit. Face turning experiments validate that the maximal prediction error is only 13.35%. As the ratio of h Dmax/r n is higher than one unit, both the prediction and experiments reveal that a conservation law exists in diamond turned surface roughness, owing to the competitive effects of kinematics, minimum undeformed chip thickness, plastic side flow and elastic recovery of materials on surface formation. Under the conservation law, the freedom control for an invariable surface roughness can be fulfilled in response to a quantitative ratio of h Dmax/r n, either through an accurate configuration of feed rate and depth of cut with fixed tool nose radius and cutting edge radius, or by a reasonable selection of tool nose radius and controlled cutting edge radius with designed feed rate and depth of cut. [Copyright &y& Elsevier]

Abstract: Third harmonic generation (THG) of high power laser is discussed in KDP crystals utilized in frequency conversion systems of large laser facilities. The far-field focal spot of the third harmonic wave is presented based on numerical simulation of the nonlinear coupled-wave equations, in which the walk-off and paraxial diffraction are taken into account and the electric field of the fundamental wave (1053nm, 1ω) pulse is phase and amplitude modulated in spatial domain. Impact of the modulation depth and frequency on the focal spot energy, the side lobes location and conversion efficiency are analyzed in detail. The results show that the side lobes location is equivalently determined by the modulation frequency of both phase modulation and amplitude modulation, while the energy-concentration is decreased mostly because of the 1ω modulation depth. Relatively, the phase modulation plays a more important role than the amplitude modulation in decreasing main lobe energy for different reasons. The phase modulation makes the energy flowing from the main lobe to side lobes, while amplitude modulation not only makes the energy flowing but also decreases tripling efficiency significantly. [Copyright &y& Elsevier]

The research on mechanical behavior and failure analysis of oxide/oxide CMC at ultra-high temperatures can broaden its application scope. The present work studied monotonic tension behavior of the oxide/oxide CMC at 800 °C∼1200 °C and two tensile rates (i.e. 5 mm/min and 0.5 mm/min). The uniaxial tensile test, fracture morphology characterization and finite element analysis were preformed to reveal the deformation and failure mechanisms of the oxide/oxide CMC at ultra-high temperature. The results show that the mechanical properties of the oxide/oxide CMC are sensitive to the temperatures and tensile rates. The stress-strain curves are almost linear at the high tensile rate and nonlinear at the low tensile rate. The ultimate tensile strength decreases significantly at low tensile rate and for temperatures higher than 1100 °C. The mechanical properties of the material are principally determined by oxide fiber/oxide matrix interface strength under low temperature and high-stress conditions, while by interlayer bonding strength under high temperature and low-stress conditions. [ABSTRACT FROM AUTHOR]

Medium manganese (Mn) steel has excellent strength and ductility and is widely used in the automobile industry and elsewhere; however, hydrogen embrittlement (HE) is considered as one of the most serious issues of its application. In this paper, in situ transmission electron microscopy was used to study the microstructural evolution and fracture micromechanisms of medium Mn steel under the influence of hydrogen and annealing. The results indicated that two specimens with different annealing processes showed transformation-induced plasticity and twinning-induced plasticity, albeit to a varying degree due to different microstructures with distinct mechanical properties. It was shown that hydrogen affected the fracture micromechanisms, which promoted the initiation of microcracks at the boundaries of martensite transformed from austenite. Moreover, the main cracks propagate in a zigzag fashion, following hydrogen charging, due to the hardness of the martensite. These findings provide directions for improving HE resistance through microstructural regulation of medium Mn steel. • In situ TEM tensile tests verify fracture mechanism of medium Mn steel. • Hydrogen promotes crack initiation at specific interface, e.g. martensite boundary. • Annealing greatly alters deformation mode, work hardening rate and the L u ¨ ders band. • The detailed fracture process of pre-hydrogen charged steel is in situ tracked. [ABSTRACT FROM AUTHOR]

The impact behavior of Fe-based amorphous coatings with various thicknesses fabricated by high-velocity-air-fuel thermal spraying was systematically investigated via 3D X-ray tomography. The results showed that the impact damage occurred principally by cracking in the coating, plastic deformation in the substrate, and delamination at the coating/substrate interface. It was found that the size of the interfacial delamination was a nonlinear function of the normalized coating thickness t c / a (i.e. the ratio of coating thickness (t c) to the contact radius (a)). Three thickness regions of distinctive damage modes were identified: thin coating region (t c / a ≤ 0.33), intermediate-thickness region (0.33 < t c / a ≤ 0.54), and thick coating region (t c / a > 0.54). For t c / a ≤ 0.33, no delamination appeared in the coating/substrate interface. With an increase from t c / a = 0.33 to t c / a = 0.54, the extent of interfacial delamination increased quickly and reached a maximum. Finally, when t c / a > 0.54, the extent of delamination decreased when t c / a increased. In addition, it was indicated that the residual stress was found to decrease with the coating thickness, reflecting that the residual stress was excluded as a predominant factor of impact damage. Furthermore, a good agreement with the Hertz impact theory and finite element modeling was identified in the case of interfacial damage: significant delamination was observed in the 600 μm coating when the maximum shear stress occurred close to the coating/substrate interface. This finding can be used to assist the design of coated components in load-bearing applications. Unlabelled Image • The impact behavior of HVAF-sprayed Fe-based amorphous coatings with various thicknesses was investigated via 3D-XRT. • The impact damage occurred by cracking in the coating, plastic deformation in the substrate and interfacial delamination. • For 200–400 μm coatings, when t c / a ≤ 0.33, the influence of the substrate on the impact behavior cannot be ignored. • Significant delamination was observed in the 600 μm coating when τ max occurred close to the coating/substrate interface. [ABSTRACT FROM AUTHOR]

Summary: Background: Psychosocial concerns represent important outcomes in studies of treatments for acne and acne scarring. Also important, but largely overlooked, is the concept of appearance. Objectives: To design an acne‐specific patient‐reported outcome measure for acne and acne scarring. Methods: We used a mixed‐methods approach. Phase I involved 21 patient interviews that were audio‐recorded, transcribed and coded. Concepts were identified and developed into scales that were refined through 10 cognitive interviews and input from 16 clinical experts. Phase II involved data collection at hospital and community‐based dermatology clinics in Canada and the U.S.A. Eligible participants were aged 12 years and older with acne and/or acne scars on the face, chest and/or back. Rasch Measurement Theory (RMT) analyses were performed to examine psychometric properties. Results: Phase I led to the development of seven scales that measure appearance of facial skin, acne (face, chest and back) and acne scars, acne‐specific symptoms and appearance‐related distress. In phase II, 256 patients completed the ACNE‐Q. RMT analysis provided evidence that the items of each scale worked together conceptually and statistically. Most participants scored within the range of measurement for each scale (81·9–93·1%). Reliability was high, with person separation index values and Cronbach alpha values > 0·90 for the appearance scales, ≥ 0·87 for appearance‐related distress and ≥ 0·75 for symptoms. Worse scores on appearance scales correlated with worse symptom scores and more appearance‐related distress. Conclusions: The ACNE‐Q is a rigorously developed instrument that can be used to measure appearance and other patient‐centred concerns. What's already known about this topic? Acne is a common dermatological condition that can have an important impact on psychosocial function.Current patient‐reported outcome measures specific to acne focus mostly on measuring psychological and social impact. What does this study add? The ACNE‐Q provides a set of independently functioning scales that measure appearance of facial, back and chest acne, acne scarring and facial skin.Additional scales measure appearance‐related distress and acne symptoms. What are the clinical implications of this work? ACNE‐Q provides the dermatology community with a rigorously developed patient‐reported measure for acne that can be applied in clinical trials, research and patient care.The measurement of appearance by ACNE‐Q scales is more comprehensive than in other instruments providing important information on appearance of their acne and/or acne scars from the patient perspective. Respond to this article Linked Comment: Gabes. Br J Dermatol 2019; 181:1121–1122. Plain language summary available online [ABSTRACT FROM AUTHOR]

Biochar (BC) application could improve plant nitrogen (N) utilisation and potentially reduce N fertiliser requirements. However, the fate of N in crop–soil systems and the metabolic responses of crops under conditions of BC co‐applied with reduced N are not well understood.The urea‐15N isotope and pot experiments with three BC rates (0%, 5% and 15%; w/w) combined with three N fertiliser levels (100% N, 85% N and 55% N) were conducted for maize. The metabolome, 15N abundance and gene expression in plants were analysed using nuclear magnetic resonance, gas isotope mass spectrometry and quantitative real‐time reverse transcription PCR, respectively.The results showed that recovery of N by maize ranged from 27.4% to 23.6% and decreased as the N application rate decreased (from 100% to 55%) without BC addition, but ranged from 24.6% to 29.4% when BC was added at a rate of 5% and increased as the N application rate decreased. BC addition had major effects on global metabolic profiles and metabolic networks at the metabolomics level as well as on the expression of related genes (zmGS1and zmAS1) and the content of mineral N (NO3−, NO2− and NH4+) in maize seedlings; moreover, the interaction effects of the BC application rates and N fertiliser levels were evident (P ≤ 0.001).BC addition induced a decrease in the flux toward sugar hydrolysis and maintained homeostasis in the amino acid pool, which was perturbed by reduced N levels; after which the maize plants adapted to the reduced N condition, and the N recovery efficiency ultimately improved with reduced N loss. [ABSTRACT FROM AUTHOR]

Highlights • Supplementation of branched-chain VFA with or without rumen protected folic acid was evaluated. • Milk yield, true protein content and yield as well as feed efficiency increased with both supplements. • Ruminal fermentation characteristics, cellulolytic bacteria and enzyme activities were improved. • Serum GHRH, GH, IGF-1 and total protein increased with both supplements. • There was no interaction detected between branched-chain VFA and rumen protected folic acid. Abstract This study evaluated the effects of branched-chain volatile fatty acids (BCVFA) and rumen protected folic acid (RPFA) supplementation on lactation performance, ruminal fermentation, nutrient digestion and blood metabolites in dairy cows. Fifty-six multiparous Chinese Holstein cows (3.2 ± 1.1 of parity, 631 ± 16.4 kg of body weight [BW], 65 ± 2.6 days in milk [DIM] and 30.2 ± 2.1 kg of milk yield per day, mean ± SD) were blocked by lactation number, milk yield per day and DIM and were arranged into one of four groups in a randomized block design with a 2 × 2 factorial arrangement. Supplemental BCVFA (0 g/d [BCVFA-] or 80 g/d [BCVFA+]) and RPFA (0 mg/d [RPFA-] or 128 mg/d [RPFA+]) were hand-mixed into the top one-third of total mixed ration. Dietary concentrate to forage ratio was 50:50 based on a dry matter (DM) basis. Experimental periods comprised 105 days with 15 d of adaptation followed by 90 d of data collection. DM intake was increased with BCVFA supplementation, but was unaffected by RPFA. The BW changes were similar among treatments. Yields of milk, milk fat and lactose were increased, and milk true protein yield tended to increase with BCVFA or RPFA supplementation. Milk fat percentage was increased with BCVFA supplementation, but was unaffected by RPFA. Percentage of milk true protein was increased, lactose was unaltered and feed conversion ratio was decreased with BCVFA or RPFA supplementation. Ruminal pH and ammonia N concentration were decreased, but total volatile fatty acids concentration was increased with BCVFA or RPFA supplementation. Molar proportion of acetate was increased and propionate was decreased, resulting in an increased ratio of acetate to propionate with BCVFA supplementation. Acetate and propionate molar proportion and the ratio of acetate to propionate were not affected by RPFA. Digestibilities of DM, organic matter, crude protein, non-fiber carbohydrates, neutral detergent fibre and acid detergent fibre were increased with BCVFA or RPFA supplementation. Similarly, activities of caboxymethyl-cellulase, cellobiase, xylanase, pectinase, α-amylase and protease and abundance of R. albus, R. flavefaciens , F. succinogenes , B. fibrisolvens and P. ruminicola were increased. However, R. amylophilus abundance was not affected by BCVFA and increased with RPFA supplementation. Serum concentrations of glucose and non-esterified fatty acids (NEFA) were unaltered and total protein was increased with BCVFA or RPFA supplementation. Serum acetoacetate (ACAC) and BHBA were increased by BCVFA, but were decreased by RPFA. Supplementation of BCVFA or RPFA increased serum growth hormone releasing hormone, growth hormone and insulin-like growth factor-1. These results indicated that lactation performance, ruminal fermentation, nutrient digestion and hormone secretion improved due to the stimulated ruminal bacteria growth and enzyme activity with BCVFA or RPFA supplementation, but no BCVFA × RPFA interaction was detected during the trial. [ABSTRACT FROM AUTHOR]

Highlights • Ruminal fermentation was improved with coated folic acid (CFA) supplementation, but depressed by soybean oil (SO) supplementation. • Microbial cellulolytic enzyme activities and ruminal NDF degradability increased with supplementary CFA, but decreased with SO supplementation. • The growth of cellulolytic bacteria was promoted by supplementary CFA, but depressed by SO supplementation. • Urinary excretion of purine derivatives increased with CFA, but decreased with SO supplementation. • CFA + SO interacted: CFA reduced the negative effects of SO on ruminal fermentation. Abstract This study was conducted to evaluate the effects of dietary soybean oil (SO) and coated folic acid (CFA) supplementation on ruminal digestion kinetics, fermentation, microbial enzyme activity and bacterial abundance in Jinnan beef steers. Eight ruminally cannulated Jinnan beef steers, averaging 15 months of age and 415 ± 5.6 kg of body weight (BW; Mean ± S.E.), were used in a replicated 4 × 4 Latin square design by a 2 × 2 factorial arrangement. Two levels of CFA (0 mg [FA-] or 115 mg per kg dietary DM [FA + ]) were supplemented to the diets without or with SO supplementation (0 g [SO−] or 30 g per kg dietary dry matter [DM] [SO + ]). Steers were fed a total mixed ration with ensiled corn forage to concentrate ratio of 50:50 on a DM basis. The SO × CFA interaction was observed for ruminal pH, total VFA concentration, molar proportions of acetate and propionate, the ratio of acetate to propionate and ammonia N content. Ruminal pH increased with SO supplementation, but decreased with CFA supplementation. Ruminal total VFA concentration, acetate molar proportion and acetate to propionate ratio decreased with SO supplementation, but increased with CFA supplementation. Ruminal ammonia-N content decreased with SO or CFA supplementation. No SO × CFA interaction was observed for nutrient degradability and digestibility. Degradability of neutral detergent fibre (NDF) and digestibility of DM, organic matter, NDF and acid detergent fibre decreased with SO supplementation, but increased with CFA supplementation. Degradability and digestibility of crude protein was not affected by SO supplementation, but increased with CFA supplementation. Pectinase activity was unaltered, whereas, other microbial enzyme activity, bacterial abundance and total PD excretion were affected by SO × CFA interaction. Activities of carboxymethyl-cellulase, cellobiase and xylanase and abundance of R. albus, R. flavefaciens, F. succinogenes and B. fibrisolvens decreased with SO supplementation, but increased with CFA supplementation. Activities of pectinase, α-amylase and protease as well as total bacterial abundance were not affected by SO supplementation, but increased with CFA supplementation. Total protozoal abundance decreased with SO supplementation, but was not affected by CFA supplementation. Abundance of P. ruminicola and R. amylophilus increased with SO or CFA supplementation. Total PD excretion increased with CFA supplementation, but decreased with SO supplementation. The results suggested that ruminal fermentation, NDF degradability, protozoal abundance, cellulolytic bacterial abundance and enzyme activity decreased with dietary SO supplementation, but increased with CFA supplementation. The supplementation of CFA in the SO diet could relieve the negative effects of SO on ruminal fermentation. [ABSTRACT FROM AUTHOR]

Nutritional intake and reproductive allocation are strongly associated and dietary energy restriction (ER) or surpluses can affect reproductive capacity. The objective of this study was to investigate the effect of energy levels on sheep testicular development. Three-month old Hu sheep were assigned to four groups, and fed diets containing different levels of energy (Control, maintenance energy; ER1, 85% maintenance energy; ER2, 70% maintenance energy; ER3, 55% maintenance energy). Two months later, half the sheep in each group were euthanized, whereas the remaining sheep were euthanized after a further 3 months feeding on a compensatory energy diet. The testicular weight and reproductive hormone levels of the Hu sheep were investigated. Differences in the testes of ER3 and control group sheep were investigated at the transcriptional level using high-throughput sequencing. The results showed that the testicular weights had decreased in the energy-restricted rams compared with the controls, and that the testosterone concentration in ER3 group rams was significantly lower than that in other compared groups ( P  < 0.05). After the period of compensatory feeding, however, ER3 sheep testicular weight and testosterone concentrations were similar to those of the control group sheep. In addition, the RNA sequencing results revealed that 81 genes were upregulated and 180 genes were downregulated in the ER3 group compared with the control group. Moreover, based on the enriched steroidogenesis, meiosis and kinases pathways, a number of candidate genes potentially involved in the regulation of testicular development or reproduction of Hu sheep, including CYP11A1, ALDH3B1, FDFT1, WNT2, PGR and INSR , were screened. Quantitative real-time polymerase chain reaction analysis results correlated well with the sequencing data. Taken together, this study provides a first insight into the development of the testis with dietary energy restriction in sheep and shows that these changes are associated with alterations in transcriptomic. The sheep testis mRNA database were extended in this study will provides novel candidate regulators for future genetic and molecular studies on sheep testicular development associated with energy restriction, which will contribute to improving the reproductive performance of sheep. [ABSTRACT FROM AUTHOR]

Inspired by insect flapping wings, a novel flapping wing rotor (FWR) has been developed for micro aerial vehicle (MAV) application. The FWR combines flapping with rotary kinematics of motions to achieve high agility and efficiency of flight. To demonstrate the feasibility of FWR flight and its potential MAV application, an extensive and comprehensive study has been performed. The study includes design, analysis, manufacture, experimental and flight test of a flyable micro FWR model of only 2.6 g weight. By experiment, the FWR kinematic motion and aerodynamic lift were measured using high speed camera and load cells. Within a range of input power, the difference between the measured aerodynamic force and the analytical results by a quasi-steady model was found to be within 3.1%–15.7%. It is noted that the FWR aeroelastic effect plays a significant role to obtain an ideal large angle of attack especially in up-stroke and enhance the FWR performance. Further analysis of the unsteady aerodynamic characteristics has been carried out based on the detailed airflow field of the FWR in a flapping cycle by CFD method. A successful vertical take-off and short hovering flight of the micro FWR model has been achieved for the first time in the research field. The flight test demonstrates the FWR feasibility and its unique feature of flight dynamics and stability for the first time. These characteristics have also been simulated by using ADAMS software interfaced with the aerodynamic model. [ABSTRACT FROM AUTHOR]

Agricultural soils are strong sources of the potent greenhouse gas N 2 O but soil N 2 O emissions and its microbial mechanism in greenhouse field, especially ammonia-oxidizing microorganisms are unclear. We characterized a potential response in soil N 2 O production and its influencing factors, such as soil temperature, moisture, pH, and inorganic nitrogen to different irrigation methods named drip irrigation (DI), subsurface irrigation (SI) and furrow irrigation (FI) in a long-term irrigation field in greenhouse. The abundance and metabolic activity of ammonia oxidizing archaea (AOA) and bacteria (AOB) in greenhouse soils were also investigated using amoA gene as a molecular biomarker by quantitative PCR and 13 CO 2 -DNA-stable isotope probing (SIP) methods. Results showed that N 2 O flux peaks would obviously occur within 1–8 days after each irrigation. The soil N 2 O flux in FI treatment was significantly higher than that in DI and SI treatments ( P <  0.05). Correlation analysis between soil N 2 O flux and its influencing factors indicated that soil moisture and nitrate nitrogen were substantially affecting soil N 2 O emissions compared with soil temperature, pH and ammonium nitrogen. The copy numbers of AOA amoA gene in FI treatment were significantly higher than those in DI and SI treatments ( P <  0.05), while there is no significant difference of AOB amoA gene among the three treatments. Also, the copy numbers of AOA amoA gene were significantly higher than those of AOB amoA gene. The 13 CO 2 -DNA-SIP and phylogenetic tree results indicated only AOB dominantly involved in Nitrosospira genera was active during the nitrification process in the three irrigation methods. Our findings provided direct evidence that drip irrigation and subsurface irrigation could effectively reduce soil N 2 O emissions in greenhouse. AOA was dominant in abundance, while AOB played a key role in microbial community under the conditions of this experiment. Future characterization of the mechanisms for ammonia oxidation requires deeper studies in the greenhouse field. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of branched-chain volatile fatty acids (BCVFA) supplementation on growth performance, ruminal fermentation, nutrient digestibility, hepatic lipid content and gene expression of dairy calves. Forty-eight Chinese Holstein male calves (10 months of age; 345 ± 6.4 kg of body weight [BW]) were assigned randomly to four treatments with 0, 60, 120 and 180 mg BCVFA per kg BW per day for each calf. Supplemental BCVFA was hand-mixed into the top third of the daily ration and fed to calves for 100 days to the experimental treatments. Supplementation of BCVFA in calves ration increased ADG and feed conversion linearly. Dry matter (DM) intake was unaffected, but digestibilitiy of DM, organic matter, crude protein, ether extract, neutral detergent fibre and acid detergent fibre increased linearly with increasing levels of BCFVA supplementation. Similarly, Supplementation of BCVFA linearly decreased ruminal pH and ammonia-N but increased total VFAs. Molar proportion of acetate linearly increased, whereas propionate linearly decreased and the ratio of acetate to propionate increased linearly with increasing BCVFA in rations. Relative mRNA expressions of peroxisome-proliferator-activated receptor α and carnitine palmitoyl transferase-1 linearly increased with BCVFA levels. The results suggested that BCVFA supplementation improved ruminal fermentation, nutrient digestibility and growth of calves with promoted hepatic lipid oxidation. Due to the unsignificant difference between 120 and 180 mg groups for all parameters, the optimum supplementary dose of BCVFA was 120 mg per kg BW per day. [ABSTRACT FROM AUTHOR]

The dynamic collision of an on-chain same charged polaron pair with an off-chain counterion trapped in an impurity molecule, under the influence of an external electric field, has been investigated using a nonadiabatic evolution method. We demonstrate that the bipolaron, the exciton and the trion are the main products in such a reaction, and that the trion can be formed by both the direct recombination of a positive polaron pair with a counterion and the secondary recombination of the formed bipolaron with either a trapped polaron, a charged defect, or an impurity of the opposite sign, which is consistent with the experimental evidence qualitatively. Meanwhile, our results show that the strength of the applied electric field and the impurity potential play important roles in the polaron pair-impurity collision. These results are expected to be helpful to understand the electroluminescence and conductivity in conjugated polymers. [ABSTRACT FROM AUTHOR]

This experiment was to evaluate the effects of rumen-protected pantothenate (RPP) on ruminal fermentation, microbial enzyme activity, bacteria population and urinary excretion of purine derivatives in growing beef steers. Eight ruminally cannulated first-generation crossbred (Blonde d′Aquitaine × Simmental) beef steers, averaging 12 months of age and 363 ± 7 kg of body weight (BW), were allocated into a replicated 4 × 4 Latin square design. Four treatments were control, low-RPP (LRPP), medium-RPP (MRPP) and high-RPP (HRPP) with 0, 0.32, 0.48 and 0.64 g RPP per kg dietary DM, respectively. Steers were fed a total mixed ration and dietary concentrate to corn silage ratio was 50:50 based on a dry matter (DM) basis. The experiment included four periods and lasted for 96 days, each period contained 14 days of adaptation and 10 days of data collection. Ruminal pH decreased linearly with increasing RPP supplementation and was lower for MRPP than for control. Ruminal total VFA concentration increased linearly with increasing RPP supplementation and was higher for MRPP than for control. The acetate to propionate ratio increased linearly due to the unchanged acetate molar proportion and the tendency towards decreased propionate proportion. Ruminal DM and neutral detergent fibre degradability of corn silage increased quadratically, whereas DM and crude protein degradability of concentrate mix increased linearly with increasing RPP supplementation. Activities of carboxymethyl-cellulase, cellobiase, xylanase and α-amylase increased linearly and was higher for MRPP than for control. Populations of R. albus, R. flavefaciens, F. succinogenes, B. fibrisolvens, P. ruminicola and R. amylophilus increased linearly and quadratically with increasing RPP supplementation. Urinary excretion of purine derivatives increased linearly with increasing RPP supplementation and was higher for HRPP and MRPP than for LRPP and control. The results indicated that dietary supplementary RPP improved ruminal fermentation, in situ ruminal degradation and urinary excretion of purine derivatives by stimulating bacteria growth and microbial enzymes secretion. It is suggested that supplementary RPP regulated bacteria growth and microbial enzymes secretion in a dose-dependent manner. Under the current experimental condition, the appropriate dose of RPP was at 0.48 g per dietary DM for growing crossbred beef steer. [ABSTRACT FROM AUTHOR]

A combinatorial film of the LaCo 1-x Cr x O 3 system was fabricated using the LaCoO 3 and LaCrO 3 targets at the NIST Pulsed Laser Deposition (PLD) facility. As the ionic size of Cr 3+ is greater than that of Co 3+ , the unit cell volume of the series increases with increasing x. Using a custom screening tool, the Seebeck coefficient of LaCo 1-x Cr x O 3 approaches a measured maximum of 286 μV/K, near to the cobalt-rich end of the film library (with x ≈ 0.49). The resistivity value increases continuously with increasing x. The measured power factor, PF , of this series, which is related to the efficiency of energy conversion, also exhibits a maximum at the composition of x ≈ 0.49, which corresponds to the maximum value of the Seebeck coefficient. Our results illustrate the efficiency of applying the high-throughput combinatorial technique to study thermoelectric materials. [ABSTRACT FROM AUTHOR]

Photochemical smog, characterized by high concentrations of ozone (O 3 ) and fine particles (PM 2.5 ) in the atmosphere, has become one of the top environmental concerns in China. Volatile organic compounds (VOCs), one of the key precursors of O 3 and secondary organic aerosol (SOA) (an important component of PM 2.5 ), have a critical influence on atmospheric chemistry and subsequently affect regional and global climate. Thus, VOCs have been extensively studied in many cities and regions in China, especially in the North China Plain, the Yangtze River Delta and the Pearl River Delta regions where photochemical smog pollution has become increasingly worse over recent decades. This paper reviews the main studies conducted in China on the characteristics and sources of VOCs, their relationship with O 3 and SOA, and their removal technology. This paper also provides an integrated literature review on the formulation and implementation of effective control strategies of VOCs and photochemical smog, as well as suggestions for future directions of VOCs study in China. [ABSTRACT FROM AUTHOR]

This experiment was done to investigate the influences of supplementary rumen-protected folic acid (RPFA) on ruminal fermentation parameters, microbial enzyme activity, cellulolytic bacteria and urinary excretion of purine derivatives in growing beef steers. Eight ruminally fistulated Jinnan beef steers (398.4 ± 1.9 kg) were used in a repeated 4 × 4 Latin square experimental design. The treatments were: control (without RPFA), low RPFA (LRPFA), medium RPFA (MRPFA) and high RPFA (HRPFA) with 0, 0.6, 1.2 and 1.8 g RPFA per steer per day, respectively. The dietary corn silage to concentrate ratio was 50:50 (dry matter [DM] basis). The dry matter intake was confined to 95% of voluntary intake. Mean ruminal pH was quadratically reduced with altering RPFA supplementation, and was the lowest for MRPFA and HRPFA, highest for the control, and intermediate for the LRPFA. Ruminal total VFA concentration was quadratically increased with increasing RPFA supplementation and was higher in MRPFA than in control. The ratio of acetate to propionate was quadratically increased due to the increased acetate concentration and the unchanged propionate concentration. Ruminal degradabilities of DM and neutral detergent fibre of corn silage, and DM and crude protein of concentrate mix increased quadratically with increasing RPFA supplementation. Ruminal enzyme activity of cellobiase, xylanase, pectinase and α-amylase quadratically increased and was higher in MRPFA than in control. The populations of B. fibrisolvens , R. albus, R . flavefaciens and F. succinogenes quadratically increased with altering the supplementary PRFA. Urinary excretion of purine derivatives quadratically increased with altering RPFA supplementation and was higher in HRPFA and MRPFA than in LRPFA and control. The results indicated that dietary supplements of RPFA improved ruminal fermentation, in situ ruminal degradation and urinary excretion of purine derivatives. It was suggested that the RPFA regulated the activity of rumen microbe or enzymes in a concentration-dependent manner. Under this experimental condition, the appropriate dose of RPFA was at 1.2 g/d for steer. [ABSTRACT FROM AUTHOR]

• Complete set of transient thermal-hydraulic analysis models is developed based on Modelica language for the system of SCO2-cooled reactor coupled with Brayton cycle. • By comparing with the results of FROBA-SCO2, SACOS-SCO2, KAIST and TRA-SCR, the model developed in this paper is proved to be precise. • Reactivity insertion accident without protection of the SCO2-cooled reactor is simulated and analyzed. The thermal-hydraulic characteristics of the core and other components in MMR system are obtained. • According to the results and analysis, MMR system has certain inherent safety and the developed Modelica model can simulate the system for more detailed transient performances under different accidents. Supercritical carbon dioxide (SCO 2) direct cycle gas fast reactor system has attracted lots of attention from different institutions worldwide. Most of the research on SCO 2 -cooled reactors put emphasis on the design and optimization of core parameters, but few on detailed thermal-hydraulic analysis for SCO 2 -cooled reactors coupled with Brayton cycle. To supplement the lack of research in this area, a program based on Modelica language is established for transient simulations of SCO 2 -cooled reactor system. Then, the results of developed Modelica model are compared with code results obtained by GAMMA+, FROBA-SCO2 and SACOS-SCO2, which achieves good agreement. Based on the developed models and codes, thermal-hydraulic characteristics of SCO 2 -cooled reactor coupled with simple Brayton cycle under the conditions of reactivity insertion accident are studied. According to the validation and transient simulations for different reactivity insertion accidents, Modelica model developed in this paper shows great ability in getting more detailed transient performance of coupled SCO 2 -cooled reactor system under different working conditions. [ABSTRACT FROM AUTHOR]

A novel CuFeNiMn medium-entropy alloy without sigma-sensitive Cr and rare Co was firstly proposed. Cu-rich FCC phases was controlled to distribute dispersedly in FCC matrix. Significant strengthening effect was obtained when annealing at 800 °C for 1 h, which could be ascribed to the Cu-rich particles by dislocation by-pass mechanism. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effects of dietary supplements of rumen-protected folic acid (RPFA) on lactation performance, energy balance, reproductive performance and blood parameters of dairy cows. Ninety-six multiparous Holstein cows were assigned to four groups of 24 each according to their previous 305-days milk production. The treatments were: control, low RPFA (LRPFA), medium RPFA (MRPFA) and high RPFA (HRPFA) with 0–3 g RPFA/cow per day, respectively. Supplements of RPFA were top-dressed and manually mixed into the upper one third of the ration during the morning feeding from 3 weeks before the expected calving date to 15 weeks after parturition. Dry matter (DM) and net energy (NE) intakes, milk yield, milk protein content and production increased linearly ( P < 0.05) with increasing RPFA supplementation, whereas milk fat content and production only tended to be linearly increased. Cows supplemented with RPFA showed a similar pattern ( P < 0.05) of decreased loss of body weight (BW) and improved energy balance (expressed in MJ/cow/day) during the 105 days in milk (DIM) period. Concentrations of glucose in plasma, folate and methionine in serum increased linearly ( P < 0.05), whereas concentrations of non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHBA) and serum homocysteine linearly ( P < 0.01) decreased. Total conception rate and the percentage of cows pregnant at 150 DIM linearly increased ( P < 0.05), DIM at first breeding and breeding per conception tended to change linearly with increasing RPFA supplementation. These results indicated that supplementary RPFA in cow diets had positive effects on feed intake and milk production, increased concentrations of plasma glucose and serum folates, decreased plasma concentrations of NEFA and BHBA and serum concentration of homocysteine, and improved energy balance and reproductive performance. These data suggest that RPFA improves lactation, energy balance and reproductive performance in a dose-dependent manner. [ABSTRACT FROM AUTHOR]

Highlights: [•] Grain size of AZ91 alloy reduced from 500μm to 124μm by SiC inoculants. [•] Solution route is 400°C+16h for spheroidization without notable grain growth. [•] Pressurized solidification favors the flow and feeding capacity of residual liquid. [•] Relative density increases continuously with the increase of holding pressure. [•] Tensile strength reaches 167MPa for modified alloy with applied pressure. [ABSTRACT FROM AUTHOR]

The bismuth germanium oxide (BGO) electromagnetic calorimeter, which is characterized by a large detection energy range of 5 GeV–10 TeV for high-energy cosmic-ray electrons/positrons (CREs) and γ -rays, is the key sub-detector of the Dark Matter Particle Explorer (DAMPE). A careful and comprehensive calibration is essential for conducting accurate detector energy measurement. In this study, we present a method based on the ATmospheric Muon Neutrino Calculation 3-dimensional version (ATMNC3) software package, which achieves a stable and homogeneous inter-calibration in orbit for the DAMPE calorimeter. [ABSTRACT FROM AUTHOR]

• Coated zinc sulfate (CZS) could be used as a Zn supplement in dairy cows. • Supplementing 20 or 30 mg Zn/kg DM as CZS in diets containing 31.2 mg Zn/kg DM stimulated lactation performance and rumen fermentation in cows. • Dietary Zn was required for rumen microbial growth and enzyme activity. This study was to evaluate impacts of zinc sulfate (ZS) and coated ZS (CZS) supplementation on milk performance, nutrient digestibility and rumen fermentation. Forty-five Holstein dairy cows were assigned in a randomized block design to one of five treatments: control, ZS supplementation (30 mg Zn/kg dry matter [DM] as ZS) or CZS supplementation (10, 20 and 30 mg Zn/kg DM as CZS for LCZS, MCZS and HCZS, respectively). The experiment lasted for 110 days with 20 days for adaptation and 90 days for data collection. When comparing Zn source at same supplemental level (30 mg Zn/kg DM), milk yield and total-tract digestibility of neutral detergent fibre (NDF) and acid detergent fibre (ADF) tended to be higher and ruminal activities of xylanase, cellobiase, pectinase and protease and serum alkaline phosphatase (ALP) were higher for HCZS than for ZS. Increasing CZS addition linearly increased DM intake and yields of milk, milk fat and milk protein but did not affect milk lactose yield, milk composition content and feed efficiency. Digestibility of DM, organic matter, crude protein, NDF and ADF, ruminal total volatile fatty acids content and acetate to propionate ratio linearly increased but ammonia N content linearly decreased with increasing CZS addition. Quadratic responses were observed for proportions of acetate and propionate. Activities of cellulase and protease and populations of total bacteria, fungi, protozoa, dominant cellulolytic and amylolytic (proteolytic) bacteria responded linearly and positively with increasing CZS addition. Increasing CZS addition linearly increased liver Zn and blood total protein, albumin, ALP and Zn. Results indicated that CZS could be used as a Zn supplement in cows, and supplementing 20 or 30 mg/kg DM of Zn from CZS stimulated performance, nutrients digestion and ruminal fermentation and improved Zn status in cows fed diets containing 31.2 mg Zn/kg DM. [ABSTRACT FROM AUTHOR]

• Guanidinoacetic acid (GAA) or betaine (BT) increased growth performance and rumen microbial populations in bulls. • Supplementing BT changed rumen fermentation pattern with greater acetate production. • Supplementing GAA at 0.6 g/kg DM did not affect blood concentrations of folate, homocysteine and methionine. • No additional effect on performance was found with both GAA and BT compared to GAA or BT alone. This study evaluated the influences of guanidinoacetic acid (GAA) and betaine (BT) on growth performance, nutrient digestion and ruminal fermentation in bulls. Forty-four Angus bulls were blocked by live body weight and then randomly divided into four groups in a 2 × 2 factorial design. Betaine of 0 or 0.6 g/kg dry matter (DM) was added to diets containing 0 or 0.6 g/kg DM GAA, respectively. The experiment included a 20 day period for adaptation and a 60 day period for data collection. Average daily gain and feed efficiency were increased by GAA or BT but no further increase was observed for supplementing BT and GAA together than for addition with BT or GAA alone. Supplementary GAA or BT did not influence DM intake but increased apparent digestibility of DM, organic matter (OM), crude protein (CP) and acid detergent fibre (ADF). Digestibility of neutral detergent fibre (NDF) was increased by GAA inclusion but was unaltered with BT provision. Ruminal pH reduced but total volatile fatty acids and ammonia nitrogen elevated with dietary inclusion of GAA or BT. Rumen short chain fatty acids percentages and fermentation pattern were not influenced by GAA. Dietary inclusion of BT increased molar proportions of acetate, valerate, isobutyrate and isovalerate as well as the ratio of acetate to propionate. Rumen populations of Ruminococcus flavefaciens and Fibrobacter succinogenes increased with addition of GAA or BT and the increase was greater when BT was added in diets with GAA compared to diets without GAA. Addition of GAA or BT increased activities of cellobiase, xylanase, α-amylase and protease and populations of total bacteria, cellulolytic bacteria and Ruminobacter amylophilus but did not affect Prevotella ruminicola. Addition of BT increased carboxymethyl-cellulase and pectinase activities and total fungi population. Blood creatine content was increased by GAA or BT and was greater for addition of GAA and BT together than for GAA or BT addition alone. Serum contents of glucose, folate, arginine and methionine were unchanged but total protein increased with GAA or BT provision. Blood homocysteine content was unaffected by GAA but decreased with BT supplementation. The data showed that GAA or BT addition improved growth performance and feed efficiency but supplementing GAA and BT together did not further increase the performance of bulls when compared with GAA or BT inclusion alone. [ABSTRACT FROM AUTHOR]

• Dietary addition of laccase did not affect dry matter intake but elevated average daily gain in Holstein bulls. • Apparent nutrient digestibility and neutral detergent fibre degradability of corn silage increased with laccase addition. • Dietary laccase addition increased total volatile fatty acids and altered fermentation mode to more propionate production. • Addition of laccase increased fiber degrading enzyme activity and copies of total bacteria, fungi and fibrolytic bacteria. This study investigated the impacts of dietary laccase addition on performance, nutrient digestion, rumen fermentation and microbiota in bulls. Eight Holstein bulls with rumen cannula were allocated in a repeated 4 × 4 Latin square experiment design into four groups: control, low-laccase (LL), medium-laccase (ML) and high-laccase (HL) with 0, 0.2, 0.4 and 0.6 g/kg dietary dry matter (DM) of laccase addition, respectively. Addition of laccase did not influence DM intake but higher average daily gain and lower feed conversion ratio were found for bulls in ML group. Apparent nutrients digestibility elevated linearly with increasing laccase supplementation. Digestibility of DM and organic matter in ML, crude protein (CP) in ML and HL as well as neutral detergent fibre (NDF) and acid detergent fibre in LL, ML and HL were higher. Increasing laccase addition quadratically decreased ruminal pH, quadratically increased total volatile fatty acids content and changed ruminal fermentation mode to more propionate formation. Ruminal ammonia-N concentration decreased linearly. Ruminal degradability of concentrate CP and corn silage DM were higher for bulls in ML, but degradability of corn silage NDF was higher for bulls in ML and HL groups. Activities of cellobiase, α-amylase and laccase were higher for bulls in ML group. Populations of total bacteria, methanogens, Fibrobacter succinogenes , Ruminococcus albus , Butyrivibrio fibrisolvens , Prevotella ruminicola and Ruminobacter amylophilus increased linearly, but fungi and R. flavefaciens increased quadratically. Urine excretion of total purine derivatives was higher for bulls receiving medium or high level of laccase supplementation. The results suggested that dietary laccase supplementation increased performance and nutrient digestibility, and the appropriate addition level of laccase was 0.4 g/kg DM in bulls. [ABSTRACT FROM AUTHOR]

• Addition of palm fat powder (PFP) and coated folic acid (CFA) increased milk yield and feed efficiency. • Improved energy balance was only observed for PFP addition. • Addition of CFA stimulated nutrient digestibility, ruminal microbial growth, and fermentation. This study investigated the effects of palm fat powder (PFP) and coated folic acid (CFA) supplementation on performance, energy balance, nutrient digestion, ruminal fermentation and blood metabolites in early lactation dairy cows. Thirty-two multiparous Holstein dairy cows were arranged into four treatments in a 2 × 2 factorial randomized block design. Supplemental PFP (0 g/d [PFP−] or 500 g/d [PFP+]) and CFA (0 mg/d [CFA−] or 135 mg/d of folic acid from CFA [CFA+]) were mixed into the top one-third of the daily ration from d 52 prepartum (based on expected calving date) to d 42 postpartum. Dry matter intake was unaltered but milk yield, milk fat content and feed efficiency increased with PFP or CFA supplementation. Milk protein content was not affected by PFP but increased with CFA supplementation. Body weight change was not affected by PFP or CFA supplementation. Energy balance increased with PFP supplementation but decreased with CFA supplementation. Apparent total-tract digestibility of dry matter, organic matter, crude protein, non-fiber carbohydrates, aNDF, ADF and gross energy, ruminal pH and total volatile fatty acids concentration were unchanged with PFP supplementation but increased with CFA supplementation. Ruminal acetate to propionate ratio was decreased by PFP but increased with CFA supplementation. Lower ammonia-N was observed for PFP or CFA supplementation. Activity of α-amylase and population of Butyrivibrio (B.) fibrisolvens and Ruminobacter (Rb.) amylophilu increased but total protozoa decreased with PFP supplementation. Supplementation of CFA increased activity of cellobiase, xylanase, pectinase, α-amylase and protease and population of total bacteria, fungi, protozoa, Ruminococcus (R.) albus , R. flavefaciens , Fibrobacter succinogenes , B. fibrisolvens , Prevotella ruminicola and Rb. amylophilus. Significant PFP × CFA interaction was not observed during the trial. The results indicated that dietary supplementation of PFP or/and CFA had the potential to improve performance of early lactation dairy cows. [ABSTRACT FROM AUTHOR]