bluuebunny/crossref_metadata_2025 huggingface dataset:
Crystallizing highly-likely subspaces that contain an unknown quantum state of light
Authors: Teo Yong Siah , Mogilevtsev Dmitri , Mikhalychev Alexander , Řeháček Jaroslav , Hradil Zdeněk
Published: December 2016

In continuous-variable tomography, with finite data and limited computation resources, reconstruction of a quantum state of light is performed on a finite-dimensional subspace. In principle, the data themselves encode all information about the relevant subspace that physically contains the state. We provide a straightforward and numerically feasible procedure to uniquely determine the appropriate reconstruction subspace by extracting this information directly from the data for any given unknown quantum state of light and measurement scheme. This procedure makes use of the celebrated statistical principle of maximum likelihood, along with other validation tools, to grow an appropriate seed subspace into the optimal reconstruction subspace, much like the nucleation of a seed into a crystal. Apart from using the available measurement data, no other assumptions about the source or preconceived parametric model subspaces are invoked. This ensures that no spurious reconstruction artifacts are present in state reconstruction as a result of inappropriate choices of the reconstruction subspace. The procedure can be understood as the maximum-likelihood reconstruction for quantum subspaces, which is an analog to, and fully compatible with that for quantum states.
Post-Translational Incorporation of L-Phenylalanine into the C-Terminus of α-Tubulin as a Possible Cause of Neuronal Dysfunction
Authors: Ditamo Yanina , Dentesano Yanela M. , Purro Silvia A. , Arce Carlos A. , Bisig C. Gastón
Published: December 2016

α-Tubulin C-terminus undergoes post-translational, cyclic tyrosination/detyrosination, and L-Phenylalanine (Phe) can be incorporated in place of tyrosine. Using cultured mouse brain-derived cells and an antibody specific to Phe-tubulin, we showed that: (i) Phe incorporation into tubulin is reversible; (ii) such incorporation is not due to de novo synthesis; (iii) the proportion of modified tubulin is significant; (iv) Phe incorporation reduces cell proliferation without affecting cell viability; (v) the rate of neurite retraction declines as level of C-terminal Phe incorporation increases; (vi) this inhibitory effect of Phe on neurite retraction is blocked by the co-presence of tyrosine; (vii) microtubule dynamics is reduced when Phe-tubulin level in cells is high as a result of exogenous Phe addition and returns to normal values when Phe is removed; moreover, microtubule dynamics is also reduced when Phe-tubulin is expressed (plasmid transfection). It is known that Phe levels are greatly elevated in blood of phenylketonuria (PKU) patients. The molecular mechanism underlying the brain dysfunction characteristic of PKU is unknown. Beyond the differences between human and mouse cells, it is conceivable the possibility that Phe incorporation into tubulin is the first event (or among the initial events) in the molecular pathways leading to brain dysfunctions that characterize PKU.
Validation of plasma microRNAs as biomarkers for myotonic dystrophy type 1
Authors: Perfetti A. , Greco S. , Cardani R. , Fossati B. , Cuomo G. , Valaperta R. , Ambrogi F. , Cortese A. , Botta A. , Mignarri A. , Santoro M. , Gaetano C. , Costa E. , Dotti M. T. , Silvestri G. , Massa R. , Meola G. , Martelli F.
Published: December 2016

Non-invasive and simple to measure biomarkers are still an unmet need for myotonic dystrophy type 1 (DM1). Indeed, muscle biopsies can be extremely informative, but their invasive nature limits their application. Extracellular microRNAs are emerging humoral biomarkers and preliminary studies identified a group of miRNAs that are deregulated in the plasma or serum of small groups of DM1 patients. Here we adopted very stringent selection and normalization criteria to validate or disprove these miRNAs in 103 DM1 patients and 111 matched controls. We confirmed that 8 miRNAs out of 12 were significantly deregulated in DM1 patients: miR-1, miR-27b, miR-133a, miR-133b, miR-206, miR-140-3p, miR-454 and miR-574. The levels of these miRNAs, alone or in combination, discriminated DM1 from controls significantly, and correlated with both skeletal muscle strength and creatine kinase values. Interestingly, miR-133b levels were significantly higher in DM1 female patients. Finally, the identified miRNAs were also deregulated in the plasma of a small group (n = 30) of DM2 patients. In conclusion, this study proposes that miRNAs might be useful as DM1 humoral biomarkers.
Structural basis for broad neutralization of HIV-1 through the molecular recognition of 10E8 helical epitope at the membrane interface
Authors: Rujas Edurne , Caaveiro Jose M. M. , Partida-Hanon Angélica , Gulzar Naveed , Morante Koldo , Apellániz Beatriz , García-Porras Miguel , Bruix Marta , Tsumoto Kouhei , Scott Jamie K. , Jiménez M. Ángeles , Nieva José L.
Published: December 2016

The mechanism by which the HIV-1 MPER epitope is recognized by the potent neutralizing antibody 10E8 at membrane interfaces remains poorly understood. To solve this problem, we have optimized a 10E8 peptide epitope and analyzed the structure and binding activities of the antibody in membrane and membrane-like environments. The X-ray crystal structure of the Fab-peptide complex in detergents revealed for the first time that the epitope of 10E8 comprises a continuous helix spanning the gp41 MPER/transmembrane domain junction (MPER-N-TMD; Env residues 671–687). The MPER-N-TMD helix projects beyond the tip of the heavy-chain complementarity determining region 3 loop, indicating that the antibody sits parallel to the plane of the membrane in binding the native epitope. Biophysical, biochemical and mutational analyses demonstrated that strengthening the affinity of 10E8 for the TMD helix in a membrane environment, correlated with its neutralizing potency. Our research clarifies the molecular mechanisms underlying broad neutralization of HIV-1 by 10E8, and the structure of its natural epitope. The conclusions of our research will guide future vaccine-design strategies targeting MPER.
A indicator of visceral adipose dysfunction to evaluate metabolic health in adult Chinese
Authors: Xia Ming-Feng , Chen Ying , Lin Huan-Dong , Ma Hui , Li Xiao-Ming , Aleteng Qiqige , Li Qian , Wang Dan , Hu Yu , Pan Bai-shen , Li Xue-Jun , Li Xiao-Ying , Gao Xin
Published: December 2016

Visceral adipose dysfunction is a major cause of metabolic disorders. However, there is lack of a clinical index for prediction of visceral fat dysfunction in Asians. The present study aims to establish a visceral adiposity index for evaluation of metabolic health status in Chinese, the largest Asian ethnic group. 485 subjects were recruited from Lianqian Community, Xiamen and received abdominal computed tomography(CT) for visceral fat area. A Chinese visceral adiposity index (CVAI) was created using multivariate linear regression analyses, and was further validated in 6495 subjects recruited from Changfeng Community, Shanghai. CVAI was well associated with visceral obesity (r = 0.68, P < 0.001) and HOMA-IR (r = 0.60, P < 0.001). The AUROCs were 0.89(0.88–0.90), 0.72(0.71–0.73), 0.69(0.68–0.71) and 0.67(0.65–0.68) for determination of metabolic syndrome, hypertension, diabetes and prediabetes, respectively. CVAI was more valuable compared to BMI and waist circumference in evaluation of metabolic risks (all P < 0.001), even in subjects with metabolically unhealthy normal weight (MUNW) and metabolically healthy obese/overweight (MHO). This study demonstrates that CVAI is a reliable and applicable index for evaluation of visceral fat dysfunction in Chinese. It might be used to evaluate metabolic health status in Asians.
Erratum: Can native clonal moso bamboo encroach on adjacent natural forest without human intervention?
Authors: Bai Shangbin , Wang Yixiang , Conant Richard T. , Zhou Guomo , Xu Yong , Wang Nan , Fang Feiyan , Chen Juan
Published: December 2016

Scientific Reports 6: Article number: 31504; published online: 07 September 2016; updated: 01 December 2016
Fabrication of polypyrrole-coated magnetic particles for quinone extraction from fine atmospheric particulate matter
Authors: Jiao Zhe , Bai Yunhe , Zeng Yanyan , Lv Sihao , Fan Hongbo , Huang Weiqing
Published: December 2016

In this paper, a magnetic solid phase extraction method was developed for the analysis of five quinones (oxygenated polycyclic aromatic hydrocarbons) in fine atmospheric particulate matter (diameters within eight ranges and all below 10 μm).
Hydrogen-bond dynamics at the bio–water interface in hydrated proteins: a molecular-dynamics study
Authors: Nandi Prithwish K. , English Niall J. , Futera Zdenek , Benedetto Antonio
Published: December 2016

Hydration water's dynamical-crossover lies not at the origin of the protein residues' larger-amplitude motions, but rather arises as a consequence thereof.
Is iron nitride or carbide highly active for oxygen reduction reaction in acidic medium?
Authors: Sun Tao , Jiang Yufei , Wu Qiang , Du Lingyu , Zhang Zhiqi , Yang Lijun , Wang Xizhang , Hu Zheng
Published: December 2016

The high ORR activities in acidic medium for the so-called Fe2N- and Fe3C-based catalysts actually originate from the trace of Fe–Nx/C moieties (x ≥ 4) rather than the Fe2N or Fe3C phases themselves.
Organic-free synthesis of {001} facet dominated BiOBr nanosheets for selective photoreduction of CO2 to CO
Authors: Wu Dan , Ye Liqun , Yip Ho Yin , Wong Po Keung
Published: December 2016

BiOBr nanosheets synthesized in the presence of nitric acid exhibited high selectivity for photocatalytically converting CO2 into CO.
Adsorption-intensified degradation of organic pollutants over bifunctional α-Fe@carbon nanofibres
Authors: Zhu Zhigao , Xu Ying , Qi Benyu , Zeng Gaofeng , Wu Ping , Liu Guojuan , Wang Wei , Cui Fuyi , Sun Yuhan
Published: December 2016

Uniform α-Fe encapsulated in activated carbon nanofibres exhibited excellent activity, high stability and easy magnetic separation for PMS activation.
Stimulus-responsive polymers
Authors: Roth Peter J. , Lowe Andrew B.
Published: December 2016

Peter J. Roth and Andrew B. Lowe introduce this themed issue for Polymer Chemistry on stimulus-responsive polymers.
Pd(ii)-Catalyzed oxidative dearomatization of indoles: substrate-controlled synthesis of indolines and indolones
Authors: Fang Xinxin , Gao Shang , Wu Zijun , Yao Hequan , Lin Aijun
Published: December 2016

A Pd(ii)-catalyzed oxidative dearomatization of indoles provides a straightforward access to diverse fused indolines and indolones bearing C2-oxygenated quaternary stereocenters.
Feature extraction from resolution perspective for gas chromatography-mass spectrometry datasets
Authors: Ma Pan , Zhang Zhimin , Zhou Xinyi , Yun Yonghuan , Liang Yizeng , Lu Hongmei
Published: December 2016

Automatic feature extraction from large-scale datasets is one of the major challenges when analyzing complex samples with gas chromatography-mass spectrometry (GC-MS).
Synergistic photovoltaic–thermoelectric effect in a nanostructured CdTe/Bi2Te3 heterojunction for hybrid energy harvesting
Authors: Luo Bingwei , Deng Yuan , Wang Yao , Gao Min , Zhu Wei , Hashim Hasan Talib , García-Cañadas Jorge
Published: December 2016

A synergistic photovoltaic and thermoelectric effect takes place in a single heterojunction solar cell that consists of a p-type CdTe nanorod array and n-type Bi2Te3 nanostructures.
Cadmium(ii) complexes with a 4-acyl pyrazolone derivative and co-ligands: crystal structures and antitumor activity
Authors: Luo Hua-Ying , Li Jin-Yu , Li Yue , Zhang Li , Li Jin-Yao , Jia Dian-Zeng , Xu Guan-Cheng
Published: December 2016

The antitumor activity of three mononuclear cadmium(ii) complexes and an apoptosis assay of complex 3 were investigated.
Synthesis of water-dispersible silicon-containing hydroxyapatite nanoparticles with adjustable degradation rates and their applications as pH-responsive drug carriers
Authors: Lin Kaili , Zhang Na , Yin Zhilan , Shen Yuhui , Zhang Weibin
Published: December 2016

An environmentally friendly method was developed to synthesize water-dispersible Si-HAp nanoparticles with adjustable degradation rates, high loading capacities for anticancer drugs, and sustained and pH-dependent drug release properties.
Solution-processed Cu2XSnS4 (X = Fe, Co, Ni) photo-electrochemical and thin film solar cells on vertically grown ZnO nanorod arrays
Authors: Ghosh Anima , Chaudhary Dhirendra K. , Biswas Amrita , Thangavel Rajalingam , Udayabhanu G.
Published: December 2016

Devices with ITO/ZnO/ZnS/CFTS/Au, ITO/ZnO/ZnS/CCTS/Au and ITO/ZnO/ZnS/CNTS/Au architectures exhibited PCE values of 2.73, 3.23 and 2.71% and displayed good electrocatalytic behaviors.
Correction: Titanium aminophosphates: synthesis, characterization, antimicrobial and cytotoxicity studies
Authors: Rajini Anumula , Adepu Ajay Kumar , Chirra Suman , Venkatathri Narayanan
Published: December 2016

Correction for ‘Titanium aminophosphates: synthesis, characterization, antimicrobial and cytotoxicity studies’ by Anumula Rajini et al., RSC Adv., 2015, 5, 87713–87722.
Protein structure refinement using a quantum mechanics-based chemical shielding predictor
Authors: Bratholm Lars A. , Jensen Jan H.
Published: December 2016

We show that a QM-based predictor of a protein backbone and CB chemical shifts is of comparable accuracy to empirical chemical shift predictors after chemical shift-based structural refinement that removes small structural errors (errors in chemical shifts shown in red).
Versatile routes for synthesis of diarylamines through acceptorless dehydrogenative aromatization catalysis over supported gold–palladium bimetallic nanoparticles
Authors: Taniguchi Kento , Jin Xiongjie , Yamaguchi Kazuya , Nozaki Kyoko , Mizuno Noritaka
Published: December 2016

In the presence of Au–Pd/TiO2, various kinds of symmetrically and unsymmetrically substituted diarylamines could effectively be synthesized starting from various combinations of substrates.
Formation mechanism of overlapping grain boundaries in graphene chemical vapor deposition growth
Authors: Dong Jichen , Wang Huan , Peng Hailin , Liu Zhongfan , Zhang Kaili , Ding Feng
Published: December 2016

The formation mechanisms of two different types of grain boundaries (GBs), the weakly bound overlapping GB and the covalent bound GB, during graphene domain coalescence are revealed by both theoretical modeling and experimental observations.
Click mediated high-performance anion exchange membranes with improved water uptake
Authors: Mondal Abhishek N. , He Yubin , Wu Liang , Khan Muhammad Imran , Emmanuel Kamana , Hossain Md. Masem , Ge Liang , Xu Tongwen
Published: December 2016

HLTEI and BPPO based novel high-performance comb-shaped AEMs were fabricated. The prepared membrane showed improved water uptake.
Bipolar nitrogen-doped graphene frameworks as high-performance cathodes for lithium ion batteries
Authors: Huang Yanshan , Wu Dongqing , Dianat Arezoo , Bobeth Manferd , Huang Tao , Mai Yiyong , Zhang Fan , Cuniberti Gianaurelio , Feng Xinliang
Published: December 2016

As cathode materials in lithium ion batteries, nitrogen-doped graphene frameworks (N-GFs) manifest excellent specific capacity and cycle stability, owing to the fast surface faradaic reactions of pyridinic N and pyridinic N-oxide with both p- and n-doped states.
Flexible, conductive, porous, fibrillar polymer–gold nanocomposites with enhanced electromagnetic interference shielding and mechanical properties
Authors: Li Jun , Liu Hu , Guo Jiang , Hu Zhen , Wang Zhijiang , Wang Bin , Liu Li , Huang Yudong , Guo Zhanhu
Published: December 2016

Flexible lightweight conductive nanocomposites prepared by self-assembly of gold nanoparticles on charged polymer nanofibers show enhanced EMI shielding effectiveness and mechanical properties.
Adaptive SU/MU‐MIMO scheduling schemes for LTE‐A downlink transmission
Authors: Guo Wei , Fan Jiancun , Li Geoffrey Ye , Yin Qinye , Zhu Xiaolong
Published: December 2016

We investigate multi‐user (MU) multiple‐input multiple‐output (MIMO) scheduling under the practical constraints in long‐term evolution advanced (LTE‐A) downlink cellular networks. The authors first derive the received signal model in MU‐MIMO systems when there exist both inter‐stream interference (ISI) and inter‐user interference (IUI) at each user device. Based on this, they formulate the optimisation problem as joint user pairing, precoding matrix indicator (PMI) selection, and resource block (RB) allocation to maximise the total system throughput. The authors then develop a codebook grouping technique for user pairing and PMI selection in MU‐MIMO. With the help of codebook grouping, the authors propose some suboptimal and low‐complexity scheduling algorithms to improve system throughput. From system‐level simulation, the proposed algorithms can improve the network throughput significantly when exploiting only limited feedback designed for single‐user (SU) MIMO in the LTE‐A specification.
Switched control of repeated scalar non‐linear systems via sliding mode control technique
Authors: Liu Xinxin , Su Xiaojie , Song Yong‐Duan , Yang Rongni , Wang Lei
Published: December 2016

This study focuses on the hybrid switched controller design issue for a type of repeated scalar non‐linear systems with stochastic disturbance based on sliding mode control (SMC) approach. By constructing the diagonally dominant Lyapunov functional appropriately, sufficient conditions of mean‐square exponential stability are first proposed for the resulting non‐linear stochastic system, which possess a strictly dissipativity performance. The authors' attention is focused on constructing a desirable sliding mode surface and further analysing its sliding mode motion. Then, a hybrid switched controller is designed to ensure the accessibility of the pre‐specified switching sliding mode surface. Finally, the feasibility and effectiveness of the designed SMC technique are illustrated by the numerical example.
Double‐layer miniaturised‐element metasurface for RCS reduction
Authors: Long Mao , Jiang Wen , Gong Shuxi
Published: December 2016

A novel double‐layer miniaturised‐element metasurface is investigated to obtain the in‐band and out‐of‐band radar cross‐section reduction (RCSR) of a patch antenna. The modified traditional square‐rings, with centre edges bent inward into hollow crosses and eight resistors welt on each side, are adopted to form the first‐layer metasurface. It is for the out‐of‐band incident wave absorption. The second layer consists of four V‐shaped polygonal metallic patches and four resistors. Each resistor connects two adjacent V‐shaped patches together. The second layer is for in‐band (2.76–2.86 GHz) RCSR of the antenna. Simulated and measured results showed that the RCSR of the new antenna with proposed metasurface has been dramatically accomplished from 2.0 to 15.5 GHz. It is worth mentioning that the obtained RCSR at 2.8 GHz is as much as 14.6 dB and the maximum RCSR at 10 GHz is 30.1 dB. The monostatic radar cross section (RCS) of the proposed antenna is significantly reduced over a wide angular domain at the same time. Since the metasurface has little effects on the radiation performance of the antenna, this method can be used to achieve antenna RCSR at broadband and over wide angular range.
Printed quadrifilar helix antenna with enhanced bandwidth
Authors: Zhang Zhi‐Ya , Yang Long , Zuo Shao‐Li , Rehman Masood Ur , Fu Guang , Zhou Chuangzhu
Published: December 2016

A circular polarised printed quadrifilar helix antenna with enhanced bandwidth is proposed in this study. The helix antenna offers a very compact size and comprises of four arms with varying width, four open stubs, a feeding network and a metal ground plane. The different widths of the helix arms are employed to improve the impedance bandwidth while their varying pitches generate a cardioid radiation pattern. The antenna exhibits a voltage standing wave ratio ≤ 2 in the frequency range of 1.43–1.63 GHz offering impedance bandwidth of 12%. Good radiation characteristics with high gain, a wide 3 dB axial ratio beamwidth of 180° along with small size makes this antenna an excellent candidate for satellite communications and navigation systems.
G‐shaped band‐notched ultra‐wideband MIMO antenna system for mobile terminals
Authors: Toktas Abdurrahim
Published: December 2016

Low‐profile band‐notched G‐shaped ultra‐wideband (UWB) multiple input multiple output (MIMO) antenna design for mobile terminals has been presented. In this context, two UWB MIMO antenna systems have been designed: The first is with square elements and the second is with G‐shaped elements. An MIMO antenna with two symmetrical square elements each of 8 × 8 mm2 operating between 2.2 and 13.3 GHz was firstly designed for the UWB applications. Each square element was fed through a 50‐Ω microstrip transmission line (MTL). A thin strip line was designed at the end of MTL to provide impedance matching. Although the isolation level between the elements was satisfactory for efficient MIMO implementation, a T‐shaped strip on the ground was employed to further improve the isolation for low frequency. The frequency range of 4.4–6.2 GHz which is an important band of wireless local area network (WLAN) standard was then notched by forming a G‐shaped structure on the square element. The performance of G‐shaped antenna system was studied in terms of important antenna characteristics and MIMO parameters. The results demonstrate that the G‐shaped MIMO antenna has nearly omnidirectional patterns, stable gain and good diversity performance besides having low‐profile elements.
Expression of microRNA in male reproductive tissues and their role in male fertility
Authors: Pratt S. L. , Calcatera S. M.
Published: December 2016

MicroRNA (miRNA) are small non-coding RNA, approximately 22 nucleotides in length, that regulate gene expression through their ability to bind to mRNA. The role of miRNA in cellular and tissue development is well documented and their importance in male reproductive tissue development is actively being evaluated. They are present in spermatogonia, Sertoli and Leydig cells within the testis and are present in mature spermatozoa, indicating roles in normal testicular development, function and spermatogenesis. Their presence in spermatozoa has led to postulations about the roles of male miRNA during early embryonic development after fertilisation, including chromatin restructuring and possible epigenetic effects on embryo development. MiRNAs are also present in body fluids, such as blood serum, milk, ovarian follicular fluid and seminal fluid. Circulating miRNAs are stable, and aberrant expression of cellular or extracellular miRNA has been associated with multiple pathophysiological conditions, the most studied being numerous forms of cancer. Considering that miRNAs are present in spermatozoa and in seminal fluid, their stability and the relatively non-invasive procedures required to obtain these samples make miRNAs excellent candidates for use as biomarkers of male reproduction and fertility. Biomarkers, such as miRNAs, identifying fertile males would be of financial interest to the animal production industry.
133 COMPARISON OF ENDOMETRIAL TRANSCRIPTOME CHANGES BETWEEN IPSI- AND CONTRALATERAL HORNS DURING DIESTROUS AND ITS RELATIONSHIP WITH THE ABILITY TO SUPPORT CONCEPTUS ELONGATION IN CATTLE
Authors: Sánchez J. M. , Passaro C. , Forde N. , Browne J. A. , Fernández B. , Mathew D. J. , Kelly A. K. , Butler S. T. , Behura S. , Spencer T. E. , Lonergan P.
Published: December 2016

Data from embryo transfer studies indicate that transfer to the uterine horn contralateral to the ovary containing the corpus luteum (CL) reduces pregnancy rate. The aim of this study was to compare the ipsi- v. contralateral horns in terms of (1) endometrial gene expression and (2) the ability to support conceptus growth to Day 14. In Experiment 1, endometrial samples from the ipsi- and contralateral horns were collected from synchronized nonpregnant heifers slaughtered on Day 5, 7, 13 or 16 post-oestrus (n = 5 per time point) and snap frozen for subsequent analysis. In Experiment 2, fresh Day 7 in vitro-produced blastocysts were transferred to the uterine horn(s) ipsilateral (Group I, n = 9 recipients) or contralateral to the CL (Group C, n = 8) or to both horns (i.e. bilateral, Group B, n = 9) of synchronized recipients (10 embryos transferred per horn per recipient). All recipients were slaughtered on Day 14. Reproductive tracts were recovered and each horn was flushed independently. The number and dimensions (length and width) of recovered conceptuses were recorded independently for each horn. Embryo data were analysed using PROC MIXED in SAS (SAS Institute Inc., Cary, NC, USA). The model had treatment as a fixed effect and heifer within treatment as a random effect. Experiment 1, RNA-Seq analysis of endometrium, detected 217, 54, 14, and 18 differentially expressed genes (>2-fold change, false discovery rate P < 0.05) between ipsi- and contralateral horns on Day 5, 7, 13, and 16 of the oestrous cycle, respectively. In Experiment 2, no differences were observed in the recovery rate of conceptuses on Day 14 from the 3 groups [53.3% (48/90), 48.7% (39/80), and 45% (81/180)], for the I, C, and B transfer groups, respectively. Conceptus length from the ipsi- (2.24 ± 0.35 mm) and contralateral (2.91 ± 0.38 mm) horns was not different (P > 0.05). Thus, significant differences in endometrial gene expression exist between the uterine horns ipsi- and contralateral to the CL in cattle, but those differences do not affect conceptus elongation on Day 14.
Research was supported by Science Foundation Ireland (13/IA/1983) and the Irish Department of Agriculture, Food and The Marine (13S528).
165 THE EFFECT OF INDIGENOUS CHICKEN EGG YOLK SOURCES AND TEMPERATURES ON SHORT-TERM PRESERVATION OF SOUTH AFRICAN INDIGENOUS GOAT SEMEN
Authors: Bopape M. A. , Nedambale T. L. , Pilane C. M. , Lehloenya K. C.
Published: December 2016

Egg yolk is a common constituent of semen extender and protects sperm against cold shock. Besides its protective characteristic, chicken egg yolk is mostly included in extenders for semen preservation due to its abundant availability. The aim of the study was to compare egg yolk sources from different indigenous chicken egg yolk sources and storage temperatures on short-term preservation of South African indigenous goat semen. Semen was collected from 8 South African indigenous goats with artificial vagina during the breeding season (autumn). From each of the 8 goats, 6 replicates were done. Semen samples were randomly allocated into 4 treatment groups of Tris-based extenders containing 20% of egg yolk from White Leghorn as a control, Ovambo, Potchefstroom Koekoek, and Venda chicken breeds. The extended semen samples were stored at 5 or 25°C for 48 h. Semen samples were evaluated for sperm motility using computer-aided sperm analysis sperm viability and morphology with fluorescence microscope at 0, 3, 24, and 48 h. Data was analysed with ANOVA using Stata® version 12 (StataCorp, College Station, TX, USA) statistical software to test the differences between the treatments. The total, progressive, and rapid sperm motility rates were higher in freshly collected semen (90.6, 42.7, and 33.0%, respectively) compared with treatment groups. Semen extended with Tris without egg yolk had higher total sperm motility rate at both 5°C (48.1; 51.1%) and 25°C (43.3; 53.3%) temperatures for 48 h. Semen extended with egg yolk from different egg yolk sources had no sperm motility from 24 h when stored at 25°C. Semen extended with Tris without egg yolk (48.1%) had higher sperm motility than Ovambo, Potchefstroom Koekoek, Venda, and White Leghorn (3.7, 0, 0, and 0.4%, respectively) when stored at 5°C for 48 h. However, sperm motility declined when storage increased. In conclusion, addition of egg yolk had no effect on preserving goat semen. However, Tris-based extender without addition of egg yolk preserved semen for longer period than semen extended with egg yolk regardless of egg yolk origin or chicken breed.
171 PRE-IN VITRO MATURATION OF PORCINE OOCYTES USING PITUITARY ADENYLATE CYCLASE-ACTIVATING PEPTIDE: EFFECTS ON MEIOSIS PROGRESSION AND DEVELOPMENTAL COMPETENCE
Authors: Park K.-M. , Hyun S. H.
Published: December 2016

Porcine immature oocytes derived from small follicle (SF, ≤3 mm in diameter) are able to resume meiosis, but few oocytes are capable to progress to the metaphase 2 stage. To improve capacitation of oocytes derived from SF and inhibit spontaneous maturation, a pre-in vitro maturation (IVM) system was applied to in vitro culturing of cumulus–oocyte complexes (COC). Pituitary adenylate cyclase-activating peptides (PACAP), increasing cellular cyclic adenosine 3′5′-monophosphate, have pleiotropous actions and multiple functions throughout the body as a neuropeptide. Recently, studies have described the role PACAP play in fertility and reproduction, including follicular development, antiapoptotic effects, and implantation. The purpose of this study is to improve the developmental competence of oocytes derived from SF by exogenous addition of PACAP on pre-IVM. In the conventional IVM group, COC obtained from follicles ≤3 mm in diameter (SF group) and 3 to 6 mm in diameter (medium follicles; MF group) were subjected to IVM for 42 h. In the pre-IVM group, COC obtained from SF were matured with nontreatment [pre-SF(-)PACAP group] and 1μM PACAP [pre-SF(+)PACAP group] for 18 h pre-IVM and were immediately subjected to IVM for 42 h. We examined nuclear stage assessment, intracellular reduced glutathione and reactive oxygen species levels, and embryo developmental competence by parthenogenesis and IVF. After IVM, the result of the nuclear stage assessment of groups showed that the pre-SF(+)PACAP group had the highest metaphase 2 rate in the groups (P < 0.05). Reduced glutathione levels in MF and pre-SF(+)PACAP groups showed significantly higher levels than that of the other groups (P < 0.05). After parthenogenesis, the cleavage rates were significantly (P < 0.05) higher than the others in pre-SF(+)PACAP group. In the IVF experiment, the embryo cleavage rate was significantly higher in that of MF and pre-SF(+)PACAP groups compared with that of SF and pre-SF(-)PACAP groups (P < 0.05). Moreover, no significant differences were found in the cleavage rate between MF and pre-SF(+)PACAP groups. In all groups derived from SF, the pre-SF(+)PACAP group rate of blastocyst formation and total cell number of blastocysts was significantly higher than that of the other groups (P < 0.05). These results indicated that pre-IVM system using PACAP is able to improve meiotic maturation and developmental competence although the oocytes were derived from SF.
187 9-cis RETINOIC ACID IMPROVES MATURATION RATE AND ALTERS GENE EXPRESSION OF IN VITRO-MATURED OOCYTES IN EGYPTIAN BUFFALO
Authors: Gad A. , Abu Hamed S. , Khalifa M. , El-Sayed A. , Swiefy S. A. , El-Assal S.
Published: December 2016

Retinoic acid, a metabolite of vitamin A, regulates oocyte maturation through multiple mechanisms, including gene expression modulation or preventing oxidative stress. Effects of retinoic acid during oocyte maturation have been reported in several species; however, there have been no studies illustrating these effects in buffalo. Therefore, the objective of this study was to investigate the influence of 9-cis retinoic acid (9-cisRA), an active metabolite of vitamin A, on maturation rate and gene expression during in vitro maturation of buffalo oocytes. Cumulus-oocyte complexes (n = 360) were aspirated from surface follicles of Buffalo ovaries collected from local abattoirs and transported to the laboratory in physiological saline (0.9% NaCl) containing antibiotics (100 µg mL−1 of streptomycin sulfate and 100 IU mL−1 of penicillin) and maintained at 30°C. Grade A cumulus-oocyte complexes (evenly granulated cytoplasm and surrounded by multiple layers of cumulus cells) were randomly divided into 4 groups (90 oocytes/group) and allocated in TCM-199 medium supplemented with 10% fetal bovine serum, 0.2 mM sodium pyruvate, 50 μg mL−1 of gentamycin, and 10 μg mL−1 of FSH and contained 0 (control), 5, 50, or 200 nM of 9-cisRA for maturation. After 24 h, maturation rate was calculated as a percentage based on polar body extrusion. In addition, gene expression patterns were analysed for antioxidant related genes (SOD1, CAT, GPX4, HOMX1, and PRDX1) and oocyte quality-related genes (GDF9 and BMP15) using quantitative real-time PCR with GAPDH as a housekeeping gene. Fold changes (FC) were calculated using ΔΔCt method (FC ≥2; P < 0.05). The results showed that maturation rate (based on the extrusion of polar body) was significantly higher in 5 nM 9-cisRA oocyte group (49.4 ± 2.1%) compared with the control group (35 ± 1.8%); in contrast, the 200 nM 9-cisRA oocyte group showed the lowest maturation rate (27.2 ± 2.7%). However, the 50 nM 9-cisRA oocyte group showed no significant differences (31.2 ± 3.8%) compared with control group .Oocytes treated with 5 and 50 nM 9-cisRA during in vitro maturation showed significant up-regulation of SOD1 (3.4 and 3.08 FC), CAT (2.7 and 1.8 FC), and HOMX1 (4.5 and 4 FC), and significant down-regulation of BMP15 (−3.7 and −3.6 FC), respectively, compared with the control group. Moreover, GPX4, PRDX1, and GDF9 genes were highly expressed in the 50 nM compared with the control group (13.2, 10.4, and 1.8 FC, respectively). In contrast, the 200 nM 9-cisRA group showed significant down-regulation of CAT (−60.3 FC), GDF9 (−2.5 FC), and BMP15 (−9.7 FC) compared with the control group. In conclusion, these results suggested that a low concentration of 9-cisRA (5 nM) in maturation media can improves maturation rate of buffalo oocytes and up-regulates the expression of oxidative stress response-related genes.
19 A NOVEL APPROACH TO COMPARING REPRODUCTIVE STAGE SERUM PROFILES IN MARES USING NEAR-INFRARED SPECTROSCOPY AND AQUAPHOTOMICS
Authors: Agcanas L. A. , Counsell K. R. , Shappell N. , Bowers S. , Ryan P. L. , Willard S. T. , Vance C. K.
Published: December 2016

The capability of near-infrared spectroscopy (NIR) to detect biomolecules in aqueous solutions, a sub-field of NIR called aquaphotomics, has yet to be fully explored. Aquaphotomics references water absorbance patterns and wavelength shifts in the 1st overtone of the water spectrum as they change patterns with solute composition and concentrations. Recently, NIR was used as a rapid method for detecting oestrus in Holstein raw milk and for monitoring reproductive stages in urine of the Bornean Orangutan (Pongo pygmaeus) and the giant panda (Ailuropoda melanoleuca). Near-infrared spectroscopy detects bond vibrations from organic molecules and water to create unique absorbance patterns, which are used to profile complex mixtures of biomolecules. The objectives of this study are to (1) characterise serum NIR spectral profiles for oestrus, metestrus, and diestrus in mares, and (2) determine if NIR can accurately decipher these reproductive phases from serum due to the biochemical effects of reproductive hormones. Mare oestrus cycles were assessed every other day by ultrasound and serum hormone analysis. Serum was collected via jugular venipuncture on day 0, 2, 4, 8, and 16 of each cycle for 3 consecutive cycles from each mare. Radioimmunoassay analysis of reproductive hormones E2 and P4 was used to validate and characterise the NIR spectra. Spectra were collected from triplicate samples of 200 μL of serum in a 1-mm-path-length quartz cuvette with an ADS FieldSpec®3 spectrophotometer, at room temperature (22°C). Chemometric analysis (Unscrambler® X v.10.4; CAMO Software) included pretreatment with a Savitsky-Golay second-derivative function for visual inspection of spectral features and principal component analysis (PCA), after mean centering, for distinction of reproductive status. Spectral peaks at 1347, 1367, and 1465 nm were unique to serum collected from mares in oestrus exhibiting high E2 (11.87 to 16.88 pg mL−1). Early metestrus is characterised by prominent spectral peaks at 1383 and 1437 nm, corresponding to E2 levels (0.02 to 5.29 pg mL−1) and P4 levels (0.02 to 3.61 ng mL−1). Diestrus peaks were found at 1342, 1426, and 1473 nm, when P4 levels ranged from 5.14 to 9.60 ng mL−1. In our PCA models, 98% of the total variance in serum spectra between any pair of reproductive phases was described in only 3 spectral PCs, (PC1 = 83–86%, PC2 = 9–10%, PC3 = 2–5% of total variance). The PCA scores separated into distinct groups, indicating clear spectral profiles describing each reproductive phase uniquely. In conclusion, PCA analysis and spectral variances indicate that NIR, specifically aquaphotomics, has the theoretical capability to discriminate complex mixtures of biomolecules present in mare serum during oestrus, metestrus, and diestrus reproductive states.
Study was supported by USDA-ARS Biophotonics Initiative grant #58-6402-3-018.
213 EFFECT OF NOVEL SOF MEDIUM AND L-ASCORBIC ACID DURING CRYOPRESERVATION OF IN VITRO-PRODUCED JERSEY CATTLE EMBRYOS
Authors: Higginbotham A. R. , Owen C. M. , Barceló-Fimbres M. , Campos-Chillon L. F.
Published: December 2016

Jersey embryos have high lipid content and poor cryotolerance. High lipid and reactive oxygen species concentrations are associated with poor post-thaw survival and increased post-thaw apoptosis. It was hypothesized that culturing embryos in SOF-based medium (SCF1; SOF for conventional freezing will decrease lipid content, and adding l-ascorbic acid (l-AA) to freezing media will increase cryotolerance and decrease post-thaw apoptosis. A 2 × 2 factorial design was used to compare SOF v. SCF1 and additives in freezing media (control v. L-AA). In vitro-produced blastocysts were produced in 5 replicates by aspirating oocytes (n = 975) from 2 to 8 mm follicles of abattoir ovaries, maturing for 23 h, fertilizing with semen from 1 of 2 bulls, and culturing in SOF medium or SCF1 in 38.5°C in 5% O2, 5% CO2, and 90% N2. Randomly selected Day 7 blastocysts were stained with 1 µg mL−1 Nile Red for lipid content and 300 nM Mitotracker Red CMX-Rosamine (Molecular Probes Inc., Eugene, OR, USA) for mitochondrial polarity. Remaining blastocysts were placed in 0.6 M sucrose in holding media for 2 min followed by equilibration in 1.5 M ethylene glycol and 0.5 M sucrose in holding media for 10 min with 0 or 0.1 mM l-AA. Blastocysts were thawed and assessed for re-expansion at 24 and 48 h, then stained with 4′,6-diamidino-2-phenylindole and a TUNEL assay to measure apoptosis. Ten images per stained blastocyst were acquired by confocal microscopy using a 5 µM step size at 40× magnification. Image Pro software was used to measure fluorescence of Nile Red and Mitotracker, and cells stained for TUNEL were analysed by a cell counter plug-in. Blastocyst rate, Nile Red, and Mitotracker data (Table 1) were analysed by 1-way ANOVA and means were separated by Tukey’s HSD. Post-thaw survival and apoptotic levels (Table 1) were analysed as a factorial 2 (SOF and SCF1) by 2 (0 and 0.1 mM l-AA) and means were separated by Tukey’s HSD. Results (Table 1) indicate SCF1 increased blastocyst rate and post-thaw survival and decreased lipid content (P < 0.01) with no effect on mitochondrial polarity. Post-thaw, l-AA (Table 1) increased survival (P < 0.05) but had no effect on apoptosis. The SCF1 medium increases development and lowers lipid content, whereas l-AA may lower reactive oxygen species to increase cryotolerance.

Table 1.
Effect of media on development, lipid content, and mitochondrial polarity (top part), and of media and l-AA on post-thaw survival and apoptosis (lower part)
43 CORRELATIONS OF METHODS OF SPERM ANALYSIS IN FRESH SEMEN OF SOUTH AFRICAN INDIGENOUS GOAT
Authors: Ajao O. A. , Fushai F. , Owiny D. O. , Barry D. M.
Published: December 2016

This study investigated the correlations between methods of assessing sperm qualities; namely, sperm total motility (TM), sperm vitality, acrosome integrity, DNA integrity, and sperm membrane integrity. A total of 60 ejaculates from 6 bucks were collected and the spermatozoa evaluated. The overall mean percentages of sperm TM, sperm vitality (eosin-nigrosin and propidium iodide stains), sperm acrosome integrity (Spermac and SpermBlue® stains), sperm DNA integrity (acridine orange and halotech), and sperm membrane integrity (hypoosmotic swelling test and water test) were 94.7 ± 0.5, 81.0 ± 0.6. 79.6 ± 3.7, 79.7 ± 1.8, 78.6 ± 5.3, 75.7 ± 5.5, 74.3 ± 5.1, 73.1 ± 3.5, and 73.4 ± 3.6, respectively. There were significant correlations (P < 0.05) between mean percentage live sperm evaluated with eosin-nigrosin stain and sperm TM (r = 0.813), between percentage intact acrosome assessed with SpermBlue® and sperm TM (r = 0.846), and between SpermBlue® and eosin-nigrosin (r = 0.965). There were highly significant correlations (P < 0.01) between sperm membrane integrity evaluated with HOS test and sperm TM (r = 0.871), between percentage of intact sperm DNA assessed with halotech and SpermBlue® (r = 0.832), and between percentage of intact spermatozoa DNA assessed with acridine orange and percentage intact acrosome evaluated with spermac stain (r = 0.862). Under the conditions of this study, the correlated methods of sperm analysis proved suitable for analysis of goat spermatozoa and can serve as useful indicator of potential fertility for sperm. They could be used for accurate assessment of the individual sperm cell rather the population as a whole. Motility, eosin-nigrosin stain, SpermBlue®, halotech and acridine orange stain still remain practical and valuable tools for predicting sperm fertilizing ability.
45 SURVIVAL OF HOLSTEIN IN VITRO-PRODUCED EMBRYOS CULTURED IN NOVEL SYNTHETIC OVIDUCTAL FLUID MEDIA (SCF1) AND DEHYDRATED PRIOR TO CRYOPRESERVATION
Authors: Owen C. M. , Barceló-Fimbres M. , Altermatt J. L. , Campos-Chillon L. F.
Published: December 2016

In vitro-produced (IVP) embryos experience poor cryotolerance due to metabolic changes during in vitro culture causing increased lipid accumulation and apoptosis post-thaw. We hypothesised that embryos cultured in a novel SOF for conventional freezing media (SCF1), dehydrated, and allowed longer equilibration before conventional slow freezing would increase post-thaw survival and decrease apoptosis. IVP embryos were produced in 9 replicates by oocytes (n = 3172) aspirated from abattoir ovaries, matured for 23 h, fertilized with semen from 1 of 4 bulls, and cultured in conventional SOF media or SCF1 in 38.5°C in 5% O2, 5% CO2, and 90% N2. Stage 7 blastocysts were stained with 1 µg mL−1 Nile Red for lipid content and 300 nM Mitotracker Red CMX-Rosamine for mitochondrial polarity. Remaining blastocysts were slow-frozen by 1 of 4 protocols: 2-min dehydration in 0 or 0.6 M sucrose in holding media before equilibration (10 or 20 min) in conventional freezing media (1.5 M ethylene glycol and 0.5 M sucrose in holding media). Embryos were thawed and assessed for re-expansion at 48 h and surviving embryos were stained with 4′6-diamidino-2-phenylindole (DAPI) and a TUNEL assay to determine apoptosis. Ten images per embryo were acquired by confocal microscopy using a 5-µM step size at 40× magnification. Fluorescence of Nile Red and Mitotracker was measured by IMAGE PRO software, and cells stained for TUNEL were analysed by a cell counter plug-in. Blastocyst rate, Nile Red, and Mitotracker data (Table 1) were analysed by one-way ANOVA and means separated by Tukey’s HSD. Post-thaw survival and apoptotic levels (Table 1) were analysed as a factorial 2 (SOF and SCF1) × 2 (0 and 0.6 M sucrose) × 2 (10 and 20 min), and means separated by Tukey’s HSD. No interactions occurred between factors so they were dropped from the model and only main effects are shown. Results indicate that SCF1 increased blastocyst rate, mitochondrial polarity, and post-thaw survival and decreased lipid content and post-thaw apoptosis (P < 0.01). A 20-min equilibration time decreased apoptosis (P < 0.01) and tended to increase post-thaw survival (P < 0.1), suggesting that cryotolerance is improved in embryos cultured in SCF1 and equilibrated for 20 min.

Table 1.Effect of media on development, lipid content and mitochondrial polarity (top) and of media, equilibration and dehydration on post-thaw survival and apoptosis (bottom)
68 GROWTH AND MARKET QUALITY OF PIGS BORN FROM MAGNETIC NANOPARTICLE-TREATED BOAR SPERMATOZOA
Authors: Durfey C. L. , Liao S. , Devost-Burnett D. , Dinh T. , Crenshaw M. , Willard S. T. , Ryan P. L. , Clemente H. , Feugang J. M.
Published: December 2016

Sperm ejaculates contain a heterogeneous population of nonviable and viable spermatozoal cells. Ejaculates with high concentrations of poor quality or damaged spermatozoa can greatly impair the overall fertility of males. Recently, a novel technique termed nanopurification has been developed (Feugang et al. 2015 IVF Reprod. Med. Genet. 3, 2) to noninvasively target and remove poor quality spermatozoa from boar semen. Such removal will enrich insemination doses with high quality spermatozoa to enhance fertility successes. However, effects associated with offspring born from nanopurified semen and possible meat quality assurance have yet to be extensively studied. The objective of this study was to measure the growth performance and market characteristics of pigs born from standard or nanopurified spermatozoa. Boar semen was obtained in insemination doses from a local stud and was mixed with (nanopurified) magnetic nanoparticles (iron-oxide) specifically designed to interact with acrosome-reacted and apoptotic spermatozoa. After incubation, mixed semen were placed under an electromagnetic field trapping moribund sperm to allow collection of intact and viable spermatozoa. Six gilts were bred with standard non-purified (control; n = 3) or nanopurified (n = 3) semen, with subsequent pregnancies leading to full-term birth of viable offspring. At weaning, pigs of equal sexes (5 male and 5 female) were randomly selected from control (n = 10) and nanopurified (n = 10) litters. Pigs were fed and measured until market weight, at which meat quality and carcass characteristics were assessed. Data (mean ± SEM) were analysed with Student’s t-test and SAS software (SAS Institute Inc., Cary, NC, USA). The threshold of significance was set as P < 0.05. Patterns of growth between groups were comparable up to market size (P > 0.05). Standard pork quality parameters (lean carcass weight, loin eye area, percentage of lean cuts, loin and ham colouring, etc.) revealed no significant differences between groups (P > 0.05). Dressing percentage was found higher in the nanopurified group compared with control, with a 1.5% increase (P < 0.05). Marbling score tended to be significantly higher in the nanopurified group (2.7 ± 0.15) when compared with the control (2.3 ± 0.15). Findings indicate that sperm nanopurification does not impair growth of offspring and could ultimately lead to a higher pork carcass quality. Additional research is being conducted to confirm current findings and identify further effects of nanopurification regarding offspring and carcass quality.
This work was supported by USDA-ARS Grant #58–6402–3-018.