bluuebunny/crossref_metadata_2025 huggingface dataset:
184 Establishment of Porcine Induced Pluripotent Stem Cell Lines by Adding LIN 28 Transcription Factor
Authors: Rungarunlert S. , Chakritbudsabong W. , Pamonsupornvichit S. , Sariya L. , Pronarkngver R. , Chaiwattanarungruengpaisan S. , Ferreira J. N. , Setthawonge P. , Phakdeedindan P. , Techakumphu M. , Tharasanit T.
Published: November 2018

The establishment of porcine induced pluripotent stem cells (piPSC) is important in the field of human biomedical regenerative medicine. The pig model is a more representative model than current rodent models because it better mimics human physiology in different organ systems. The piPSC can be traditionally generated by reprogramming somatic cells using 4 transcription factors (4TF: OCT4, SOX2, KLF4, and c-MYC), similarly in human. However, it is difficult to maintain the pluripotent state of reprogrammed cells and they exhibit poor differentiation capacity. Hence, the 4TF may be not enough to reprogram porcine somatic cells. This study aimed to establish piPSC by adding LIN28 (referred to as 5TF) to the traditional 4TF, via retroviral vector. Here, we report the successful establishment of 3 piPSC lines by using the 5TF. All 5TF-piPSC lines exhibited a normal karyotype (38, XY) and a typical mouse embryonic stem cell (ESC) morphology, including tightly packed and dome-like shape, even after they were propagated over 40 passages. All 5TF-piPSC lines were positive for alkaline phosphatase staining and expressed high levels of ESC-like markers (OCT4, SOX2, NANOG, and SSEA-1). Importantly, the 5TF-piPSC lines showed pluripotent capacity, as evidenced by differentiation into 3 germ layers in vitro following cystic embryoid body formation, as well as by efficiently forming teratomas containing all 3 embryonic germ layers in vivo. Moreover, the 5TF-piPSC lines showed spontaneously contractile cardiomyocytes and expressed cardiomyocyte markers (cardiac troponin T) during spontaneous cardiac differentiation using cell aggregation into spherical-like structures referred to as embryoid bodies. Thus, the addition of LIN28 TF promoted long-term pluripotency of piPSC and enhanced the ability to differentiate towards 3 embryonic germ layers and cardiac lineage.
This research project is supported by grants from the Mahidol University, Thailand.
188 The Effect of Vitamin B12 on the Differentiation of Adipose-Derived Stem Cells into Osteoblasts
Authors: Bane T. A. , Bertels J. C. , Polkoff K. M. , Rubessa M. , Wheeler M. B.
Published: November 2018

Large bone defects present a tremendous challenge to the treating surgeon. Tissue engineering using scaffolds of various sizes and shapes that contain stem cells and other osteoinductive molecules offer a potential solution to this difficult problem. The aim of this project was to evaluate if the osteogenic medium infused with vitamin B12 influences the differentiation of adipose-derived stem cells (ASC) into osteoblasts. Vitamin B12 has been shown to have a stimulatory effect on osteoclastogenesis in vitro (Vaes et al. 2009 Calcified Tissue Int. 84, 413-422). Our hypothesis was that the presence of vitamin B12 in the osteogenic medium would positively influence the number of osteoblastic nodules formed. Swine ASC were isolated as described (Monaco et al. 2009 Open Tissue Eng. Regen. Med. J. 2, 20-33). The ASC were divided in 8 different treatments: 8 concentrations of vitamin B12 in the osteogenic medium (0.1, 0.2, 1, 2, 10, and 20 μM) plus 2 control treatments (osteogenic medium without vitamin B12 and a negative control, DMEM). The medium was changed twice a week for 4 weeks. The experiment was replicated 6 times. At the end of the culture period, cells were stained with Alizarin Red and Von Kossa stains. In each well, we counted the nodules and then divided them in 2 categories: formed and forming nodules. Data was analysed using the generalized linear model (GLM) procedure in SPSS (IBM/SPSS, Armonk, NY, USA). Bonferroni’s post hoc test was used to perform statistical multiple comparison. The α-level was set at 0.01. The results showed that the concentration of 20 μM vitamin B12 was detrimental for nodule formation. Table 1 illustrates the number of formed and forming nodules in addition to their standard deviation. There was no positive effect on nodule formation when different concentrations of vitamin B12 were added to the osteogenic medium. More experiments need to be conducted to determine if vitamin B12 can act synergistically with other vitamins to produce a significant role in ASC differentiation into osteoblasts. This preliminary experiment is the first step towards the analysis of the behaviour of ASC on scaffolds with vitamin B12 incorporated into their matrix.

Table 1.The average number of formed and forming osteoblast nodules compared between treatment groups (SD in parentheses)
201 Spermatogonia Transplantation in the Chicken
Authors: Vetokh A. N. , Volkova N. A. , Kotova T. O. , Antonova E. N. , Dotsev A. V. , Zinovieva N. A.
Published: November 2018

Spermatogonia are the precursors of male germ cells. They are a valuable genetic material for the production of transgenic poultry. This technology includes isolation of the spermatogonia from male donor’s testes, transformation, and transplantation of donor cells into the sterilized recipient’s testes. The transplanted spermatogonia subsequently differentiate into male sex cells (sperm). The aim of this study was to optimize the individual stages of donor spermatogonia transplantation into the recipient’s testes to increase the effectiveness of spermatogenesis recovery. In the first stage, the spermatogenesis in male chicken was examined to determine the optimal age for isolation of spermatogonia from testes. Histological examinations of male chicken testes (n = 80 birds) were done for 8 age categories, from 1 week to 3 months. It was found that under the age of 4 weeks, the cell population in the seminiferous tubules of male chickens was represented mainly by Sertoli cells and spermatogonia. Maximum percentage of spermatogonia was 69 ± 3% at 4 weeks. At the next stage, a culture of spermatogonia was obtained. Testes of 3-week-old male chickens were used. Separation of the spermatogonia from other types of cells was based on a differential adhesive capacity. The maximum homogeneity of the cell population was established by transfer (3 times) of the supernatant containing unattached cells after 24 h of cultivation into a new culture dish for further cultivation. The cell population is represented mainly by the spermatogonia (89 ± 3%). The lentiviral transduction (pHAGE vector, ZsGreen under CMV promotor) was used to transform the resulting culture of the spermatogonia. The efficiency of spermatogonia infection with lentiviral particles (TU/mL = 2.5 × 108) was 65 ± 2%. After transformation, spermatogonia were introduced into the testes of busulfan-sterilized recipients. The optimal concentration of busulfan treatment after series of experiments from 40 to 100 mg/kg was determined. The effective dose for the removal of own spermatogenic cells was revealed at a concentration of 80 mg/kg of live weight. With complete elimination of other types of spermatogenic cells, the number of Sertoli cells and spermatogonia in the testicle tubules decreased by 39 ± 2% and 98 ± 1%, respectively, compared with the control group. The efficiency of spermatogenesis recovery was assessed based on sperm analysis that was obtained from male recipients (n = 5 birds) 4 months after the introduction of donor cells using PCR. The presence of recombinant DNA (ZsGreen) in recipients’ sperm was shown. Thus, our results indicate the prospect of using spermatogonia as a genetic material for the production of transgenic poultry.
Study was supported by the Russian Science Foundation (Project no.16-16-10059).
21 Comparative Study on Epididymal Spermatozoa Traits of Large White×Landrace and Kolbroek Boars
Authors: Netshirovha T. R. , Kanengoni A. T. , Matabane M. B. , Mphaphathi M. L. , Maqhashu A. , Bovula N. , Nkadimeng M. , Chimonyo M.
Published: November 2018

The Kolbroek pig is an early maturing breed (maturing at 4 to 5 months) that grows more slowly than modern pig breeds. There is general concern that the genetic variation within Kolbroek pig breed is becoming extinct. The aim of the study was to compare semen quality of epididymal spermatozoa derived from slaughtered Large White × Landrace and Kolbroek boars aged between 7 and 9 months. Kolbroek (n = 10) and Large White × Landrace (n = 10) boars were used in this study. Semen was collected from the head of epididymis of Kolbroek and Large White × Landrace testicles. Spermatozoa samples were extracted from head of epididymis by making incision with a razor. Semen samples were then evaluated for macroscopic (semen volume, pH, and concentration) and microscopic characteristics (spermatozoa motility and morphology). Spermatozoa motility was evaluated using computer-aided sperm analysis. Analysis of variance was used to test the difference between the breeds. The average percentage of Kolbroek and Large White × Landrace spermatozoa total motility was 92.4 ± 4.0 and 94.0 ± 4.1%, respectively (P > 0.05). The spermatozoa velocity on the curve line for Kolbroek was lower (147.2 ± 39.2) compared with the Large White × Landrace (178.3 ± 30.1 μm/s; P > 0.05). However, no significant difference was observed between the 2 breeds for rapid spermatozoa and total spermatozoa motility. No significant differences were observed in Kolbroek and Large White × Landrace boar semen volume (8 and 9 mL, respectively) or semen pH (7.0). The average spermatozoa concentration for Kolbroek and Large White × Landrace was 2.5 ± 1.2 and 1.1 ± 1.0 (×109 mL−1), respectively (P > 0.05). There were no significant differences between Kolbroek and Large White × Landrace in abnormal spermatozoa morphology. However, spermatozoa with distal, head, and midpiece abnormalities were significantly different in Kolbroek (14.0 ± 3.6; 3.6 ± 6.0 and 3.4 ± 3.7%) and Large White × Landrace breed (5.4 ± 4.7; 4.7 ± 1.0 and 0.4 ± 1.0%), respectively. In conclusion, macroscopic and microscopic epididymal spermatozoa characteristics of Kolbroek were similar to those of Large White × Landrace boars, except for head and distal spermatozoa abnormalities.
50 Effects of Cathepsin B Inhibitor E64 on the Survival Rate of Cryopreserved Semen from Korean Brindled Bulls
Authors: Kim S. W. , Kim M.-S. , Kim C.-L. , Jeon I. S.
Published: November 2018

Korean brindled cattle have distinctive coat colour and are regarded as rare cattle in the Korean peninsula. To preserve the line as a genetic resource for diversity in cattle, semen cryopreservation has been used for selection of individuals for breeding between local AI centers. Nevertheless, the survival and viability of frozen semen from Korean brindled bulls is not uniform due to the difference between the individual bulls or experimental techniques. In this study, E64, a cathepsin B inhibitor, was used at final concentrations of 0.05, 0.5, and 1 µM to test the viability of frozen semen. To prepare frozen semen, a triladyl-egg yolk diluent with 6.4% glycerol was used in a two-step freezing method with 4 different bulls with 3 repeats. A total of 12 ejaculates was diluted to a concentration of 50 to 100 × 106 mL−1 at room temperature, and slowly cooled from room temperature to 5°C in 2 to 3 h. The cooled semen was diluted 1:1 with a secondary diluent containing E64 to prepare the experimental group. After loading, 0.5-mL straws were immersed into liquid nitrogen after 10 min exposure at 5 cm above the nitrogen using a styrofoam box. The viability of spermatozoa after thawing at 37°C for 40 s was analysed by Student’s t-test. The rate of surviving sperm in the 1 µM E64 group (82 ± 4.3%) was significantly higher than that of the control group (71.2 ± 2.0%; P < 0.05). However, the 0.05 and 0.5 µM E64 treatment groups lead to similar rates (77.5 ± 2.0% and 75.0 ± 5.0%, respectively; P > 0.05). Based on these results, it is expected that E64 could be used for the improvement of productivity of frozen semen; further results on in vitro fertilization and development are ongoing.
80 Cumulus Cells Reflect the Success of IVF of Porcine Oocytes Treated with Dimethylthiourea
Authors: Lombardo D. M. , Lorenzo M. S. , Cruzans P. R. , Teplitz G. M. , Maruri A. , Tello M. F.
Published: November 2018

The aim of this study was to evaluate the effect of the antioxidant dimethylthiourea (DMTU) as a supplement during the collection and washing of cumulus–oocyte complexes (COC) on the apoptosis in cumulus cells (CC) and the competition for oocyte development in vitro. The COC were obtained by follicular aspiration. The aspiration and washing medium was TCM-199 with 10% porcine follicular fluid, 0.3 mM sodium pyruvate, and penicillin/streptomycin. Treated groups were supplemented with 2 or 20 mM DMTU. After 44 h of in vitro maturation (IVM), the percentage of nuclear maturation was determined by staining of the denuded oocytes with Hoechst 33442 (n = 357). After 18 h of in vitro fertilization (IVF) with 15°C refrigerated spermatozoa from boars of proven fertility, the suspected zygotes were stained with Hoechst 33342 to evaluate the percentages of sperm penetration (SP), monospermic penetration (MP), male pronucleus formation (MPN), and IVF efficiency (monospermic oocytes/total oocytes) (n = 260). In post-IVM CC, flow cytometry was performed after staining with annexin V-propidium iodide to evaluate apoptosis and viability (n = 90,000). Data were analysed with Flowing V 2.5.1 (http://flowingsoftware.btk.fi/). A comparison of proportion among categories was used (Fisher’s exact test), and significant differences were determined at P < 0.05. No effects were observed in the percentages of nuclear maturation. Treatments with DMTU significantly increased the SP (Control: 35%; 2 mM: 72.9%; 20 mM: 67.8%) without modifying the MP. Although in both treatments, the amount of MPN was always greater than in the control, the percentages of MPN formation did not show significant differences. The 20 mM treatment significantly increased the efficiency of IVF (control: 22.2%; 2 mM: 31.9%; 20 mM: 45.7%). In the CC of the treated groups, a significant increase in viability (control: 7.4%; 2 mM: 12.2%; 20 mM: 14.7%) and a decrease in early apoptosis (control: 60.4%; 2 mM: 55.5%; 20 mM: 57.1%) were observed. Late apoptosis decreased in the 20 mM treatment (27.3%) compared with the other experimental groups (control: 31.3%; 2 mM: 31.2%). The addition of DMTU during COC collection and washing reduce the ROS-mediated apoptosis in CC and optimize the efficiency of IVF. Besides, CC quality reflects the effect of DMTU on oocytes, so viability and apoptosis analysis on CC constitutes an interesting noninvasive method to assess oocyte competence.
81 Effects of Day 5 or 6 HEPES-Buffered Transportation Culture Medium on Developmental Competence of Bovine In Vitro-Produced Embryos
Authors: Choi W. , Owen C. M. , Barcelo-Fimbres M. , Altermatt J. L. , Campos-Chillon L. F.
Published: November 2018

Most in vitro-produced (IVP) bovine embryos are transferred fresh. Use of a HEPES/bicarbonate embryo culture medium for transportation would offer flexibility for embryo shipment and transfer. We hypothesized that embryos cultured for 36 (Day 6 embryos) or 60 h (Day 5 embryos) in a novel SCF1T medium (SOF for Conventional Freezing 1 supplemented with HEPES) would maintain developmental competence compared with bicarbonate-buffered medium SCF1 (control). In 5 replicates, IVP embryos were produced by aspirating cumulus–oocyte complexes (COC) from 2-to 8-mm follicles of abattoir ovaries. The COC (n = 1036) were matured for 23 h, fertilized with semen from 1 of 3 bulls, and cultured in SCF1 at 38.5°C, 5% CO2, 5% O2, and 90% N2 (Owen et al. 2017 Reprod. Fertil. Dev. 29, 129-130). Randomly, on Day 5 and 6 after fertilization, a subset of presumptive embryos were moved into 500-µL polystyrene vials containing 100 µL of SCF1T medium, covered with 300 µL of sterile mineral oil and cultured in a portable incubator (MicroQ iQ2, Scottsdale, AZ, USA) at 38.5°C for 60 and 36 h, respectively. On Day 7.5 post-fertilization, blastocyst rates were evaluated and embryos (n = 8) from each group were stained with 1 µg mL−1 Nile Red for lipid quantification, and 300 nM Mitotracker Red CMX-Rosamine (Thermo Fisher Scientific, Waltham, MA, USA) for mitochondrial polarity. Images were obtained with confocal microscopy and fluorescent intensity (AFU) was measured by Image J software (National Institutes of Health, Bethesda, MD, USA). Data were analysed by one-way ANOVA and means separated by Tukey’s HSD. Results (Table 1) indicate similar blastocyst rates and lipid content between embryos cultured for 36 to 60 h in SCF1T and control media (P > 0.05). However, mitochondrial polarity was lower in the Day 5 group (P < 0.05) compared with Day 6 and control groups. Results suggest that culturing embryos in SCF1T medium for 36 h maintains developmental competence compared with bicarbonate-buffered media and offers an alternative for shipment and transfer of IVP embryos. Studies involving evaluation of pregnancy rates of the present study are ongoing.

Table 1.Effects of Day 5 or 6 SCF1T embryo culture medium on development, lipid content, and mitochondrial polarity
90 Risk of Coxiella burnetii Transmission via Embryo Transfer Using In Vitro Early Caprine Embryos
Authors: Fieni F. , Alsaleh A. , de Souza-Fabjan J. , Mermillod P. , Corbin E. , Nascimento P. , Bruyas J.-F. , Pellerin J.-L.
Published: November 2018

Previous experiments using in vitro infection have shown that Coxiella burnetii has a strong tendency to adhere to the zona pellucida (ZP) of in vivo-derived goat embryos, and the washing procedure recommended by the International Embryo Technology Society (IETS) for bovine embryos failed to remove it (Alsaleh et al. 2013 Theriogenology 80, 571-575). The aim of this study was, for in vitro-produced caprine embryos infected in vitro, to (1) evaluate the ability of C. burnetii to adhere to intact ZP, (2) test the efficacy of IETS recommended rules for the washing of bovine embryos to eliminate C. burnetii, and (3) determine, by confocal microscopy, the bacteria location. One hundred ZP-intact caprine embryos, produced in vitro, at the 8- to 16-cell stage were randomly allocated into 11 batches of 8 to 9 embryos. Nine batches were incubated for 18 h with 109 Coxiella/mL of CbB1 strain (ISP, INRA, Val de Loire, France). The embryos were then recovered and washed in batches in 10 successive baths following the IETS guidelines. In parallel, 2 batches of embryos were subjected to similar procedures but without exposure to C. burnetii to serve as the control group. One of the 9 batches of infected embryos and 1 of the 2 non-infected control batches were used to perform immunolabelling to localise the bacteria. Coxiella burnetii DNA was detected by conventional PCR in all 8 batches of infected embryos after 10 successive washings. However, bacterial DNA was not detected in the embryos of the control group. The first 5 washing media of the infected groups were consistently positive and Coxiella DNA was detected up to the tenth wash in 2 batches. After immunolabelling, the observation of embryos under confocal microscopy allowed us to localise C. burnetti on the external part of the ZP without deep penetration. The presence of C. burnetii was seen on the surface of the ZP, with bacterial loads differing from one embryo to another in the same batch. This study clearly demonstrates that C. burnetii, after in vitro infection at 109 Coxiella mL−1, stick strongly to the external part of the ZP of in vitro-produced early caprine embryos without profound penetration. The 10-washings protocol recommended by IETS to eliminate the pathogenic agents of bovine embryos is unable to eliminate these bacteria in caprine embryos. Nevertheless, the finding of C. burnetii DNA by conventional PCR does not imply that the bacteria found remain infective. Further studies are required to investigate whether enzymatic or antibiotic treatment of caprine embryos infected by C. burnetii would eliminate or inactivate the bacteria from the ZP of in vitro-produced goat embryos.
Different responses of plant species to deferment of sheep grazing in a desert steppe of Inner Mongolia, China
Authors: Wang Zhen , Hou Xiangyang , Schellenberg Michael P. , Qin Yan , Yun Xiangjun , Wei Zhijun , Jiang Chao , Wang Yunfeng
Published: November 2018

This paper reports the effects of different deferments of sheep grazing on plant variables of desert steppe vegetation in Inner Mongolia during 2010–2012. The study was initiated in May 2010 and comprised five treatments: no grazing (UG), grazing throughout the growing season (G) and grazing deferment for 40, 50 and 60 days (40UG, 50UG and 60UG) from the start of the growing season in a completely randomised block design replicated three times. The plant species were classified into two functional groups (C3 and C4 species) and the relationships among species composition, biomass and annual precipitation were examined in different deferments of sheep grazing. Treatment G significantly decreased the biomass of several species compared with some of the deferred treatments and treatment UG, because of differences in grazing preferences, and, consequently, decreased the aboveground net primary productivity (ANPP). Grazing deferment for 40, 50 and 60 days significantly increased C3-species richness and biomass compared with treatment UG, whereas grazing sheep’s preferences for C4 plants at some growth stages compared with C3 plants, resulted in lower species richness and biomass of C4 plants in treatments G, 40UG and 50UG in a dry year. Similarly, different species responses to treatment 60UG resulted in an increase in ANPP in a year with more precipitation during the growing season. The annual precipitation patterns strongly affected the temporal changes in biomass as well as the responses to grazing, indicating that the plant responses in the desert steppe were co-limited by grazing and precipitation. These findings provide important insights into the management and conservation of desert steppe vegetation in Inner Mongolia.
The role of a knowledge broker in improving knowledge and understanding of climate change in the Australian rangelands
Authors: Healy Mary-Anne , Forrest Kate , Bastin Gary
Published: November 2018

This paper considers the role of a knowledge broker to coordinate and connect activity within a cross-disciplinary project to deliver climate change science and research to regional natural resource management (NRM) planning in the Australian rangelands. We use the Rangelands Cluster Project as a case study. Due to the additional challenges facing project delivery in the rangelands such as remoteness, distance and low and sparsely distributed population, the project development phase included the central role of a knowledge broker to support the project objectives: identifying climate change information needs, providing quality information that can be incorporated into NRM planning, and establishing networks of researchers and NRM planners across the rangelands. The knowledge broker facilitated a process that included face-to-face meetings, workshops, surveys, email and teleconferencing to establish relationships and identify priorities as well as to refine project outputs. This facilitation allowed clearer communication between parties who were very remote from each other and worked in different disciplines, ensuring the different expertise was brought into the project, connections made and relationships formed.
Chlamydia testing and retesting patterns at family planning clinics in Australia
Authors: Bowring Anna L. , Goller Jane L. , Gouillou Maelenn , Harvey Caroline , Bateson Deborah , McNamee Kathleen , Read Christine , Boyle Douglas , Jordan Lynne , Wardle Robyn , Stephens Anne , Donovan Basil , Guy Rebecca , Hellard Margaret
Published: November 2018

Introduction
National guidelines recommend opportunistic chlamydia screening of sexually active 16- to 29-year-olds and encourage retesting 3–12 months after a diagnosed chlamydia (Chlamydia trachomatis) infection. We assessed chlamydia testing patterns at five Australian family planning clinics (FPCs). Methods: Using routine clinic data from 16- to 29-year-olds, we calculated chlamydia testing and positivity rates in 2008–2009. Reattendance, retesting and positivity rates at retesting within 1.5–4 and 1.5–12 months of a positive result were calculated. Results: Over 2 years, 13 690 individuals aged 16–29 years attended five FPCs (93% female). In 2008, 3159 females (41.4%,) and 263 males (57.0%) were tested for chlamydia; positivity was 8% and 19%, respectively. In 2009, 3178 females (39.6%) and 295 males (57.2%) were tested; positivity was 8% and 23%, respectively. Of 7637 females attending in 2008, 38% also attended in 2009, of which 20% were tested both years. Within 1.5–4 months of a positive test, 83 (31.1%) females reattended; the retesting rate was 13% and 12% retested positive. Within 1.5–12 months of a positive test, 96 (57.5%) females reattended; the retesting rate was 36% and 13% retested positive. Conclusions: Approximately 40% of young people attending FPCs were tested for chlamydia but a smaller proportion were tested annually or were retested following chlamydia infection. High positivity rates emphasise that FPCs see a high-risk population. To maximise testing opportunities, clinical prompts, patient reminder systems and non-clinic testing strategies may be needed.
Corrigendum to: Knowledge about and experience of sexually transmissible infections in a representative sample of adults: the Second Australian Study of Health and Relationships
Authors: Grulich Andrew E. , de Visser Richard O. , Badcock Paul B. , Smith Anthony M. A. , Richters Juliet , Rissel Chris , Simpson Judy M.
Published: November 2018

Background
Sexually transmissible infections (STIs) present a substantial public health burden, and are related to modifiable sexual behaviours. Methods: Computer-assisted telephone interviews were completed by a population-representative sample of 20 094 men and women aged 16–69 years. The overall participation rate among eligible people was 66.2%. Respondents were asked questions regarding their knowledge about, self-reported history of, and testing for STIs. Results: STI knowledge was better in women, the young, people of higher socioeconomic status, those with a variety of indicators of being at high STI risk and those with a history of receiving sex education in school. Approximately one in six men and women reported a lifetime history of an STI. A history of STI testing in the last year was reported by ~one in six (17%) women and one in eight men (13%) and higher rates of testing in women were reported in most high-risk groups. The highest rates of STI testing (61%) and HIV testing (89%) were reported in homosexual men. Conclusion: Knowledge of STI-related health consequences and transmission is improving in Australians, and rates of STI testing were relatively high but were higher in women than in men. Further increases in testing rates in both sexes will be required to facilitate the early diagnosis and treatment of STIs, which is a cornerstone of STI control.
Study of performance of first year USP students with respect to their form seven marks
Authors: Dixit U J , Reddy M V
Published: November 2018

To see if there is a significant difference between the performance of the first year (100 level) students at the University of the South Pacific (USP) having different Form Seven marks, a statistical analysis is carried out using their Cumulative Grade Point Averages (CGPA). For this analysis, relevant data was obtained for the years 1997-2001 and the Form Seven marks (Total of English and best 3 subjects) were divided into the classes 250 – 259, 260 – 269, and ≥ 270. Results indicate that there is a significant difference between the CGPA of these three classes. A further analysis is then carried out by using the CGPA of only the first two classes 250 – 259 and 260 – 269 in order to determine if an increase in the entry requirements from 250 to 260 will be justified. Under its current admission regulations, USP accepts into its degree programmes all students who have passed the seventh form examination with an aggregate of at least 250 marks out of 400 with a minimum of 50% in English. The results of our analysis indicate that the minimum entry requirement could be increased to 260 if USP feels that the level of significance (Type 1 Error) is more than 3.17 percent. However, the minimum entry level should remain as 250 if the significance level is at most 3.17 percent.
A heuristic approach to constraint optimization in timetabling
Authors: Chand A.
Published: November 2018

Timetabling is a difficult (NP-complete) problem and belongs to a general class of problems known as scheduling. Due to a variety of constraints typical in different timetabling environments, it has been difficult to develop a generic solution for timetabling. This paper is an attempt to define a generic computational model for examination timetabling for predefined constraints found in the problem, and proposes a heuristic method of developing an acceptable solution. The declarative nature of the developed constraints language (based on the structured query language) is utilized to construct constraints and specify the timetabling problem as a constraint satisfaction problem. A university examination timetabling problem is used to illustrate and test the model.
Modelling the effect of vertical transmission in the dynamics of HIV/AIDS in an age-structured population
Authors: Mugisha J. Y. T. , Luboobi L. S.
Published: November 2018

We use a continuous age-structured model of McKendrick-von-Foerster type to derive a two-age
groups HIV/AIDS epidemic model. In the analysis of the model, keen interest is put on the role of
vertical transmission in the dynamics of the spread of the epidemic. The model is analysed in two scenarios: the case when the force of infection is a constant and the case when we have it as a mass action. In the first case, the only possible equilibrium is the endemic equilibrium. In this situation, we show that if all babies born to infected mothers are HIV-free we have the basic reproductive number R0 = 0 and as such the epidemic will die out. In the second case, we show that both the disease-free and endemic equilibrium points exist. We also derive conditions for their stability.
The earliest-known humans in Fiji and their pottery: the first dates from the 2002 excavations at Naitabale (Naturuku), Moturiki Island
Authors: Kumar Roselyn , Nunn Patrick D , Katayama Kazumichi , Oda Hirotaka , Matararaba Sepeti , Osborne Tamara
Published: November 2018

Until this study, the earliest-known people to have occupied the islands of Fiji were those who inhabited Matanamuani on Naigani Island as much as 1000 BC. Excavations at the Naitabale (Naturuku) site in southern Moturiki Island in June-July 2002 found an older settlement. From the nature of the pottery recovered from Naitabale, it appears to predate the Matanamuani site. Radiocarbon dates on charcoal from within the pits excavated at Naitabale confirm the site?s age. The dates show that the site could have been occupied as much as 1220 BC. A human burial (named ?Mana?) found within the older layers of Pit T1 at Naitabale is that of a female, about 1.60 m tall, of slender build. The first radiocarbon date shows that she lived at least 650 BC, probably close to 950 BC. Further tests will determine her other characteristics.
Swelling properties of chitosan hydrogels
Authors: Rohindra David R , Nand Ashveen V , Khurma Jagjit R
Published: November 2018

Chitosan hydrogels were prepared by crosslinking chitosan with glutaraldehyde. The swelling behaviour of the crosslinked and uncross-linked hydrogels was measured by swelling the gels in media of different pH and at different temperatures. The swelling behavior was observed to be dependent on pH, temperature and the degree of crosslinking. The gel films were characterized by Fourier transform Infrared spectroscopy (FT-IR) and Differential Scanning Calorimetry (DSC). The glass transition temperature (Tg) and the amount of free water in the hydrogels decreased with increasing crosslinking in the hydrogels.
Bumpiness problem and its remedy in Papaya (Carica Papaya)
Authors: Tyagi Anand P , Datt Bijendra
Published: November 2018

Papaya (pawpaw) Carica papaya L. belongs to family Caricaceae. Papaya is a very good source of fruit sugar, vitamin A, B and C. This fruit is rich in minerals and salts and makes very good food. Fiji's climate is very suitable to grow papaya and Fijian grown papaya has a big export market. Main importing countries so far are New Zealand, Japan and Canada. Another potential country for exporting papaya from Fiji is Australia. However, strict quality control and high sanitary requirements must be met to export papaya to Australia. Papaya export has gone up in last few years but unfortunately there has been no export so far to Australia. Fruit's shape, size and smoothness are important determinant factors for export market. Misshapen fruits with bumps are not acceptable in overseas market. Similarly most importing countries prefer medium sized fruits. To get good quality papaya particularly fruits without bumps, it is necessary to apply Boron in soil. Results obtained in the present investigation showed that 5.0kg Boron (applied as borax pentahydrate) per hectare was very effective in reducing bumpiness to a very minimum thus improving the quality of fruits. Boron as such showed no effect on papaya yield per plant. Three cultivars tested for average fruit weight showed acceptable fruit weight for local and export market. However, Solo Sunrise was identified as the highest average fruit yielding cultivar (tons/hectare). Improvement in quality of papaya will open up new markets for export.
Physical properties of southern Fiji waters
Authors: Chand Savin , Aung Than , Rao Shivanesh
Published: November 2018

CTD-O2 (conductivity, temperature, depth and oxygen) data collected in the southern part of Viti Levu during the cruises ('96, '97, '98, '99 & '03) of the Japanese fisheries research vessel, Koyo-maru were analyzed to identify the isothermal layers, thermocline depths, and their annual variations. Despite the difference in years and locations during the survey, seasonal thermoclines at 50-100 m depth, permanent thermoclines at 100-600 m depth and haloclines at 250-600 m depths were found. In conjunction with the temperature, salinity and depth analysis, water mass properties were also investigated, and T-S diagrams were used to identify the water mass movement and formation. The results indicate that the water mass extending from 200-600 m originated from West South Pacific Central Water and the water mass between 600-1100 m originated from Antarctic Intermediate Water.
Importance of Waisali Reserve, Vanua Levu for herpetofauna conservation in Fiji
Authors: Morrison C , Naikatini A , Thomas N , Rounds I , Thaman B , Niukula J
Published: November 2018

A two day herpetofauna survey of Waisali Reserve was conducted between 4-6th March, 2004. The survey consisted of timed active diurnal surveys for lizards and nocturnal surveys for frogs. Seven herpetofauna species were found during the survey including four endemic species. The most significant find was the confirmation of a population of the endangered Fiji ground frog (Platymantis vitianus), a species previously thought to be extirpated from mainland Fiji due to the presence of mongoose. The other significant finding was that of Emoia mokosariniveikau, only the third location known for this species. Our survey results identify Waisali Reserve as an important site for herpetofauna conservation in Fiji and we propose several management actions to facilitate conservation of herpetofauna in this area.
Antimicrobial and phytochemical potentials of arbuscular mycorrhizal fungi in Nigeria
Authors: Fapohunda S. O. , Olawuyi O. J. , Okei C. P.
Published: November 2018

Studies were carried out on the antimicrobial effect of aqueous, ethanolic, methanolic and hexane extracts of mycorrhizal fungi; Glomus clarum and Gigaspora gigantea against selected pathogenic microorganisms using well-plate and disc-diffusion methods. The highest antibacterial inhibitory activities (10 mm) were recorded for methanolic extract of Glomus clarum against Proteus vulgaris and Klebsiella pneumoniae. Hexane extract of G. clarum produced the highest antifungal activities (20 mm) against Aspergillus flavus. Generally, the antimicrobial activity of Glomus clarum extracts was significantly higher than that of Gigaspora gigantea. The minimum inhibitory concentration (MIC) was 0.1-0.4 mL for the extracts. Shigella sonnei was resistant to all extracts. The phytochemical screening carried out for the extracts showed that all extracts contained alkaloids and anthraquinone.
A multiple response stratified sampling design with travel cost
Authors: Ghufran Shazia , Khowaja Saman , Najmussehar  , Ahsan M. J.
Published: November 2018

In developing the theory of stratified sampling usually the cost function is taken as a linear function of sample sizes considering the measurement and the overhead costs only. In many practical situations the linear cost function does not approximate the actual cost incurred adequately. For example when the cost of traveling between the units selected in the sample within a stratum is significant, instead of linear cost function a cost function that is quadratic in will be a more close approximation to the actual cost. In this paper the problem of finding a compromise allocation for a multiple response stratified sample survey with a significant travel cost within strata is formulated as a multiobjective non linear programming problem. A solution procedure is proposed using the goal programming approach. A numerical example is also presented to illustrate the computational details.
A pre-eradication survey of Wedge-tailed Shearwater Puffinus pacificus on Monuriki, Mamanuca Group, Fiji
Authors: Bird Jeremy P. , Risalto Sialesi , Seniloli Elenoa , Tuamoto Tuverea
Published: November 2018

A brief visit to Monuriki, an island in Fiji’s Mamanuca group was completed in March-April 2011 to gather baseline data on the island’s population of Wedge-tailed Shearwaters Puffinus pacificus prior to the eradication of alien invasive Polynesian Rat Rattus exulans and feral goats Capra hircus from the island in December 2011. We estimated an island-wide population of 2,000-5,500 pairs of Wedge-tailed Shearwaters, the largest population recorded in Fiji. Productivity was estimated to be 40%. It is anticipated these baseline figures will be used to assess the impacts that the removal of invasive mammals has on the population.
Effects of sugarcane (Saccharum spp.) cultivation duration on some soil physical properties in Ramu Valley of Papua New Guinea
Authors: Bangita B. , Rao B. K. Rajashekhar
Published: November 2018

Repeated tillage operations for planting sugarcane (Saccharum spp.) and wheel traffic for cane harvesting and transport are known to affect the surface and sub-surface soil in Ramu sugarcane plantation of Papua New Guinea. This study examines the changes in the bulk density (SBD), penetration resistance (PR) and water infiltration (WI) parameters in cane rows and wheel tracks of a Tropofluents that have been exposed to varying durations (0, 6, 11, 16 and 22 years) of cane cultivation after being converted from grasslands. Sugarcane cultivation duration had a significant (p 10 cm depth). In response to 22 years of cane cultivation, bulk density increased by a small extent in the cane rows (2.5%), while in wheel tracks the increase was by 15%. There was a significant (p
Weathering and soil genesis from the Nasinu Basalt, South-East Viti Levu, Fiji
Authors: Morrison R. J. , Bonato (the late) J. A.
Published: November 2018

Detailed studies of basalt weathering in the South Pacific Islands are relatively rare. In order to address this gap, this study investigated weathering changes and soil formation for the predominantly fine-grained feldspar-phyric basalt flows (6.4 Ma) in the Nasinu area, about 10 km north-north-east of Suva, Fiji. In the hot humid environment locally, these rocks have been subjected to rapid and deep weathering. Three weathering profiles (Nasinu S1, S2 and S3 at approximately 60 m elevation) show features of strong kaolinitisation. Aluminium and iron enrichment in the horizons of the Nasinu weathering profiles is marked, with the presence of kaolinite, gibbsite, goethite, haematite and magnetite (grains) confirming substantial mineralogical change. Suggested mechanisms for these changes are presented. Using Soil Taxonomy, the Nasinu soil pedon (JBS-1) developed on the weathered basalt is a Typic Palehumult, very fine, mixed, isohyperthermic. A comparison is made with the weathering pattern of the Nakobalevu basalt located only about 25 km from this location.
The economic impact of fire management on timber production in the boreal forest region of Quebec, Canada
Authors: Rijal Baburam , Raulier Frédéric , Martell David L. , Gauthier Sylvie
Published: November 2018

Wildfire is an important component of the dynamics of boreal-forest ecosystems, but it can also contribute to the loss of forest resources, especially when fires escape initial attack and become large. Annual fire management costs in the province of Quebec are substantial (annual average of C$69 million for 1994–2014). The main objective of this study was to evaluate the financial impact of fire management on forest resources in Quebec. Our study includes cost–benefit analyses of nine fire management presuppression expenditure scenarios using forest and fire data for three commercially managed forest management units in the province of Quebec that experience varying mean annual burn rates (0.06–0.56%year−1). The reduction in the burn rate attributed to fire management increased the revenue from the sale of primary-processed wood product and reduced fire suppression expenditure. The combined effects of reduced suppression expenditure and increased revenue from value-added timber harvest and wood processing with a lower fire risk compensated for increased fire presuppression expenditure.
Behavioural responses of brushtail possums to live trapping and implications for trap-catch correction
Authors: Cowan Phil , Forrester Guy
Published: November 2018

Context
The behavioural response of animals to repeated trapping has implications for correction of population and monitoring indices that use catch per unit effort. Failure to account for sprung traps introduces biases into estimates of relative abundance. The time when animals get caught in live traps is often ignored, but it can provide important information about temporal movement patterns relevant to this issue.

Aims
We assessed changes in the behaviour of brushtail possums (Trichosurus vulpecula), a nocturnal marsupial, in response to repeated trapping and evaluated the potential benefit of correcting a commonly used index of abundance by using time-of-capture information.

Methods
Possums were live-trapped for three nights each month over a 20-month period in baited cage traps in a 6-ha area of native lowland forest in the southern North Island, New Zealand. Trapped possums were individually identified on first capture. Timing devices were attached to the traps to measure how long after sunset traps were sprung and how that time related to the duration of the trap-night (sunset to sunrise).

Key results
Possums were trapped, on average, ~1.25 h after sunset. Traps triggered other than by possums were sprung on average 1–2 h later. Possums caught on the first night of a trapping session were caught significantly earlier than those caught on subsequent nights. Previous capture influenced the time of subsequent capture in a trapping session in complex ways, and recapture times were generally earlier than times of first capture. Possums were captured, on average, after 11% of the duration of a trap-night and traps were triggered by animals other than possums, on average, after 22% of the duration of a trap-night.

Conclusions
The data on time of capture of possums and triggering of sprung traps suggested a need to alter the commonly used correction factor for population indices for possums, because, on average, traps were sprung for significantly more of each trapping interval (i.e. trap-night) than the half a trap-night assumed in the correction factor.

Implications
Better understanding of possum foraging behaviour is a key to more effective control using traps. In that context, more research is needed to understand the reasons for individual differences in trappability. Although it is theoretically desirable to account for sprung traps when trapping is used to index populations, to reduce biases in estimates of relative abundance, correction of the standardised residual trap-catch index for possums is probably unimportant in practical terms, because most possum control reduces numbers to levels (2–5% trap catch) at which correction of the index is unimportant. The principal exception to this is likely to be when there is a high level of non-target interference from rodents.
Estimates of sex ratio require the incorporation of unequal catchability between sexes
Authors: Pickett Evan J. , Stockwell Michelle P. , Pollard Carla J. , Garnham James I. , Clulow John , Mahony Michael J.
Published: November 2018

Context
Estimates of the sex ratio of a population are a common summary statistic used for ecological studies and conservation planning. However, methods to determine the sex ratio often ignore capture probability, which can lead to a perceived bias in the sex ratio when the sexes are detected at different rates.

Aims
To illustrate the bias from conventional count-based analysis methods for determining sex ratio by comparison with analytical methods that include capture probability.

Methods
Closed-population mark–recapture analysis was used to determine the population size of each sex within a population of green and golden bell frogs (Litoria aurea). This was then compared with the traditional count-based methods of estimating sex ratio to determine the effect of incorporating capture probability on the sex ratio estimate.

Key results
More males than females were detected during surveys, producing a male-biased sex ratio when there was no incorporation of capture probability. Mark–recapture results indicated a similar population size between the two sexes, suggesting that the sex ratio is closer to even.

Conclusions
Methods to estimate sex ratio that incorporate capture probability can significantly reduce the bias obtained from count data.

Implications
We suggest that population studies must incorporate capture probability to determine the sex ratio of a population.