422 research outputs found

    Genetic diversity among some blackberry cultivars and their relationship with Boysenberry assessed by AFLP Markers

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    Blackberry cultivation has increased its popularity in Turkey due to the use of more blackberries in Turkish cuisine. To provide farmers with well adapted blackberry cultivars, some blackberry cultivars including a Boysenberry genotype from North America has been planted to various geographical regions in Turkey. In this study, genetic diversity among these blackberry cultivars and their genetic relationship with Boysenberry and raspberry were analyzed using AFLP markers. Our results indicated that Blackberry cultivars from North America had narrow genetic background which can pose a problem for future breeding programs. Blackberry genotypes selected from Bursa province of Turkey shared all AFLP markers with the cultivar Chester, which suggests that they were not unique genotypes. Although genetic similarity between Boysenberry and blackberry was low, Boysenberry wasgenetically related to common blackberry cultivars. On the other hand, AFLP analysis was unable to detect any genetic relationship between Boysenberry and common raspberry cultivars from North America in this study

    Rotational Dynamics of Organic Cations in CH3NH3PbI3 Perovskite

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    Methylammonium lead iodide (CH3NH3PbI3) based solar cells have shown impressive power conversion efficiencies of above 20%. However, the microscopic mechanism of the high photovoltaic performance is yet to be fully understood. Particularly, the dynamics of CH3NH3+ cations and their impact on relevant processes such as charge recombination and exciton dissociation are still poorly understood. Here, using elastic and quasi-elastic neutron scattering techniques and group theoretical analysis, we studied rotational modes of the CH3NH3+ cation in CH3NH3PbI3. Our results show that, in the cubic (T > 327K) and tetragonal (165K < T < 327K) phases, the CH3NH3+ ions exhibit four-fold rotational symmetry of the C-N axis (C4) along with three-fold rotation around the C-N axis (C3), while in orthorhombic phase (T < 165K) only C3 rotation is present. Around room temperature, the characteristic relaxation times for the C4 rotation is found to be ps while for the C3 rotation ps. The -dependent rotational relaxation times were fitted with Arrhenius equations to obtain activation energies. Our data show a close correlation between the C4 rotational mode and the temperature dependent dielectric permittivity. Our findings on the rotational dynamics of CH3NH3+ and the associated dipole have important implications on understanding the low exciton binding energy and slow charge recombination rate in CH3NH3PbI3 which are directly relevant for the high solar cell performance

    Perinatal mortality associated with induction of labour versus expectant management in nulliparous women aged 35 years or over: An English national cohort study.

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    BACKGROUND: A recent randomised controlled trial (RCT) demonstrated that induction of labour at 39 weeks of gestational age has no short-term adverse effect on the mother or infant among nulliparous women aged ≥35 years. However, the trial was underpowered to address the effect of routine induction of labour on the risk of perinatal death. We aimed to determine the association between induction of labour at ≥39 weeks and the risk of perinatal mortality among nulliparous women aged ≥35 years. METHODS AND FINDINGS: We used English Hospital Episode Statistics (HES) data collected between April 2009 and March 2014 to compare perinatal mortality between induction of labour at 39, 40, and 41 weeks of gestation and expectant management (continuation of pregnancy to either spontaneous labour, induction of labour, or caesarean section at a later gestation). Analysis was by multivariable Poisson regression with adjustment for maternal characteristics and pregnancy-related conditions. Among the cohort of 77,327 nulliparous women aged 35 to 50 years delivering a singleton infant, 33.1% had labour induced: these women tended to be older and more likely to have medical complications of pregnancy, and the infants were more likely to be small for gestational age. Induction of labour at 40 weeks (compared with expectant management) was associated with a lower risk of in-hospital perinatal death (0.08% versus 0.26%; adjusted risk ratio [adjRR] 0.33; 95% CI 0.13-0.80, P = 0.015) and meconium aspiration syndrome (0.44% versus 0.86%; adjRR 0.52; 95% CI 0.35-0.78, P = 0.002). Induction at 40 weeks was also associated with a slightly increased risk of instrumental vaginal delivery (adjRR 1.06; 95% CI 1.01-1.11, P = 0.020) and emergency caesarean section (adjRR 1.05; 95% CI 1.01-1.09, P = 0.019). The number needed to treat (NNT) analysis indicated that 562 (95% CI 366-1,210) inductions of labour at 40 weeks would be required to prevent 1 perinatal death. Limitations of the study include the reliance on observational data in which gestational age is recorded in weeks rather than days. There is also the potential for unmeasured confounders and under-recording of induction of labour or perinatal death in the dataset. CONCLUSIONS: Bringing forward the routine offer of induction of labour from the current recommendation of 41-42 weeks to 40 weeks of gestation in nulliparous women aged ≥35 years may reduce overall rates of perinatal death

    Peningkatan Nilai Kalori pada Batubara Lignit dengan Metode Aglomerasi Air dan Minyak Sawit pada PT. Indonesia Power Ujp Pltu Barru

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    Penggunaan batubara di PLTU sangat bergantung kepada kualitas batubara yang digunakan, karena semakin tinggi kualitas batubara maka akan memaksimalkan pembakaran dan secara langsung akan berdampak pada produksi listrik yang dihasilkan. Penelitian ini bertujuan untuk mengetahui peningkatan nilai kalori pada batubara lignit. Pada penelitian ini digunakan metode aglomerasi dengan media air dan minyak sawit yang pada setiap sampel diberi perlakukan yang sama namun mengalami peningkatan yang berbeda. Ada tiga sampel yang digunakan pada penelitian ini dimana pada setiap sampel memiliki komposisi batubara lignit seberat 1 gram, minyak sawit sebanyak 10,20,30 ml dan air sebanyak 100 ml. Hasil penelitian ini menunjukkan bahwa semakin banyak konsentrasi minyak maka semakin tinggi kadar karbon yang diikat, sehingga dapat meningkatkan nilai kalori batubara. Dilihat dari konsentrasi 30% pada setiap sampel batubara mengalami peningkatan nilai kalori yang sebelumnya 3.765,23 cal/gr menjadi 5.279,46 cal/gr pada sampel pertama, 3.567,44 cal/gr menjadi 4.989,07 cal/gr pada sampel kedua dan 4.026,07 cal/gr menjadi 5.166,98 cal/gr pada sampel ketiga. Dari hasil penelitian ini dapat disimpulkan bahwa batubara lignit yang digunakan di PLTU dapat ditingkatkan nilai kalorinya menggunakan metode aglomerasi air dan minyak sawit

    Variation in rates of caesarean section among English NHS trusts after accounting for maternal and clinical risk: cross sectional study

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    Objective To determine whether the variation in unadjusted rates of caesarean section derived from routine data in NHS trusts in England can be explained by maternal characteristics and clinical risk factors

    Risk of placenta previa in second birth after first birth cesarean section: a population-based study and meta-analysis.

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    OBJECTIVE: To compare the risk of placenta previa at second birth among women who had a cesarean section (CS) at first birth with women who delivered vaginally. METHODS: Retrospective cohort study of 399,674 women who gave birth to a singleton first and second baby between April 2000 and February 2009 in England. Multiple logistic regression was used to adjust the estimates for maternal age, ethnicity, deprivation, placenta previa at first birth, inter-birth interval and pregnancy complications. In addition, we conducted a meta-analysis of the reported results in peer-reviewed articles since 1980. RESULTS: The rate of placenta previa at second birth for women with vaginal first births was 4.4 per 1000 births, compared to 8.7 per 1000 births for women with CS at first birth. After adjustment, CS at first birth remained associated with an increased risk of placenta previa (odds ratio = 1.60; 95% CI 1.44 to 1.76). In the meta-analysis of 37 previously published studies from 21 countries, the overall pooled random effects odds ratio was 2.20 (95% CI 1.96-2.46). Our results from the current study is consistent with those of the meta-analysis as the pooled odds ratio for the six population-based cohort studies that analyzed second births only was 1.51 (95% CI 1.39-1.65). CONCLUSIONS: There is an increased risk of placenta previa in the subsequent pregnancy after CS delivery at first birth, but the risk is lower than previously estimated. Given the placenta previa rate in England and the adjusted effect of previous CS, 359 deliveries by CS at first birth would result in one additional case of placenta previa in the next pregnancy.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

    Structure-guided design and optimization of small molecules targeting the protein-protein interaction between the von hippel-lindau (VHL) E3 ubiquitin ligase and the hypoxia inducible factor (HIF) alpha subunit with in vitro nanomolar affinities

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    E3 ubiquitin ligases are attractive targets in the ubiquitin-proteasome system, however, the development of small-molecule ligands has been rewarded with limited success. The von Hippel-Lindau protein (pVHL) is the substrate recognition subunit of the VHL E3 ligase that targets HIF-1α for degradation. We recently reported inhibitors of the pVHL:HIF-1α interaction, however they exhibited moderate potency. Herein, we report the design and optimization, guided by X-ray crystal structures, of a ligand series with nanomolar binding affinities
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