ANALISIS PERBEDAAN HEDGING KAKAO FUTURES DENGAN CROSS HEDGING KOPI ROBUSTA FUTURES YANG DIPERDAGANGAN DI BURSA BERJANGKA JAKARTA PERIODE: 2012-2016

Penelitian ini dilakukan untuk menganalisis perbedaan antara hedging kakao futures dengan cross hedging kopi robusta futures dalam meminimalkan risiko di pasar fisik komoditi kakao dengan membandingkan nilai varians return yang dihasilkan dari kedua kontrak futures. Data yang digunakan pada penelitian ini adalah data harian kakao spot, kakao futures, dan kopi robusta futures yang diperdagangkan di Bursa Berjangka Jakarta (BBJ) pada periode 2012-2016. Alat analisis yang digunakan adalah uji korelasi pearson yang bertujuan untuk menguji hubungan antara harga spot dengan futures pada saat melakukan hedging ataupun cross hedging; uji akar unit digunakan untuk melihat kestasioneritas data sebelum dilakukan uji beda; uji regresi sederhana digunakan untuk menghitung nilai ratio hedged dan ratio cross hedged; uji independent sample t-test digunakan untuk membandingkan nilai varians return yang dihasilkan dari kedua kontrak futures tersebut. Hasil analisis menunjukkan bahwa tidak terdapat perbedaan varian returns yang dihasilkan dari keduanya. Dalam hal ini, penanganan risiko pada komoditi kakao di pasar fisiknya pada saat melakukan hedging ataupun cross hedging memiliki tingkat risiko yang sama, sehingga hedging kakao futures dan cross hedging kopi robusta futures sama-sama dapat digunakan untuk meminimalkan risiko pada pasar fisik kakao

A Meta-Analysis of Parental Smoking and the Risk of Childhood Brain Tumors

<div><p>Objective</p><p>Previous studies regarding the association between parental smoking and the risk of childhood brain tumors (CBT) have reported inconsistent results. We performed a meta-analysis to summarize evidence on this association and to quantify the potential dose-response relationship.</p><p>Methods</p><p>A systematic literature search was conducted in the Medline and Embase databases. The summary relative risks (RRs) with 95% confidence intervals (CIs) were calculated. Dose–response meta-analysis was also performed for studies that reported categorical risk estimates for a series of smoking exposure levels.</p><p>Results</p><p>A total of 17 studies fulfilled the inclusion criteria. In the meta-analyses, the summary RRs (95% CIs) of CBT for maternal smoking during pregnancy, paternal smoking during pregnancy, maternal smoking before pregnancy, and paternal smoking before pregnancy were 0.96 (0.86–1.07), 1.09 (0.97–1.22), 0.93 (0.85–1.00), and 1.09 (1.00–1.20), respectively. Dose-response meta-analysis also showed no significant association between parental smoking and the risk of CBT.</p><p>Conclusions</p><p>Findings from our meta-analysis indicate that parental smoking may not be associated with a risk of CBT.</p></div

Forest plot of maternal smoking during pregnancy and the risk of CBT.

<p>Forest plot of maternal smoking during pregnancy and the risk of CBT.</p

Flowchart of study assessment and selection.

<p>Flowchart of study assessment and selection.</p

Results of subgroup analyses of the association between maternal smoking before pregnancy and the risk of childhood brain tumors.

<p>* <i>P</i> for heterogeneity of the stratum-specific summary RRs.</p

Dose-response analysis of maternal smoking during pregnancy and the risk of CBT.

<p>The solid line represents point estimates of association between maternal smoking during pregnancy and CBT risk; dashed lines are 95% CIs. Circles are the dose-specific RR estimates. The relative size of each circle is proportional to the inverse variance of the RR.</p

Exogenous Melatonin Enhances Cold Resistance by Improving Antioxidant Defense and Cold-Responsive Genes’ Expression in Banana

Accumulated evidence has revealed the mitigation effects of exogenous melatonin on cold stress in plants. In this study, to investigate the defensive roles of exogenous melatonin in banana under cold stress, we researched the influences of exogenous melatonin on the chlorophyll fluorescence parameters, antioxidant defense indexes and expression levels of cold-responsive genes in cold-stressed ‘Brazil’ banana seedlings. Results showed that 100 μM of exogenous melatonin achieved the best cold-resistance-promoting effect in banana. Exogenous melatonin treatment significantly increased the electron transfer rate, light harvesting efficiency, total antioxidant capacity, catalase and superoxidase activities and proline and soluble sugar contents and significantly reduced the accumulations of malondialdehyde, superoxide anion and hydrogen peroxide in the leaves of cold-stressed banana. In addition, under cold stress, melatonin significantly induced the expression of low-temperature-responsive genes, such as MaChiI1, MaCSD1C, MaWhy1, MaKIN10, MaADA1 and MaHOS1. It was concluded that the application of exogenous melatonin enhanced antioxidant defense and induced the expression of cold-responsive genes, thereby improving the cold resistance of banana. Our study will provide a basis for the application of exogenous melatonin in improving plant cold resistance

Exogenous Melatonin Enhances Cold Resistance by Improving Antioxidant Defense and Cold-Responsive Genes&rsquo; Expression in Banana

Accumulated evidence has revealed the mitigation effects of exogenous melatonin on cold stress in plants. In this study, to investigate the defensive roles of exogenous melatonin in banana under cold stress, we researched the influences of exogenous melatonin on the chlorophyll fluorescence parameters, antioxidant defense indexes and expression levels of cold-responsive genes in cold-stressed &lsquo;Brazil&rsquo; banana seedlings. Results showed that 100 &mu;M of exogenous melatonin achieved the best cold-resistance-promoting effect in banana. Exogenous melatonin treatment significantly increased the electron transfer rate, light harvesting efficiency, total antioxidant capacity, catalase and superoxidase activities and proline and soluble sugar contents and significantly reduced the accumulations of malondialdehyde, superoxide anion and hydrogen peroxide in the leaves of cold-stressed banana. In addition, under cold stress, melatonin significantly induced the expression of low-temperature-responsive genes, such as MaChiI1, MaCSD1C, MaWhy1, MaKIN10, MaADA1 and MaHOS1. It was concluded that the application of exogenous melatonin enhanced antioxidant defense and induced the expression of cold-responsive genes, thereby improving the cold resistance of banana. Our study will provide a basis for the application of exogenous melatonin in improving plant cold resistance

Characterization of Highbush Blueberry (<i>Vaccinium corymbosum</i> L.) Anthocyanin Biosynthesis Related MYBs and Functional Analysis of <i>VcMYB</i> Gene

As one of the most important transcription factors regulating plant anthocyanin biosynthesis, MYB has attracted great attentions. In this study, we identified fifteen candidate anthocyanin biosynthesis related MYB (ABRM) proteins, including twelve R2R3-MYBs and three 1R-MYBs, from highbush blueberry. The subcellular localization prediction results showed that, with the exception of VcRVE8 (localized in chloroplast and nucleus), all of the blueberry ABRMs were nucleus-localized. The gene structure analysis revealed that the exon numbers of the blueberry ABRM genes varied greatly, ranging between one and eight. There are many light-responsive, phytohormone-responsive, abiotic stress-responsive and plant growth and development related cis-acting elements in the promoters of the blueberry ABRM genes. It is noteworthy that almost all of their promoters contain light-, ABA- and MeJA-responsive elements, which is consistent with the well-established results that anthocyanin accumulation and the expression of MYBs are influenced significantly by many factors, such as light, ABA and JA. The gene expression analysis revealed that VcMYB, VcMYB6, VcMYB23, VcMYBL2 and VcPH4 are expressed abundantly in blueberry fruits, and VcMYB is expressed the highest in the red, purple and blue fruits among all blueberry ABRMs. VcMYB shared high similarity with functionally proven ABRMs from many other plant species. The gene cloning results showed that VcMYB had three variable transcripts, but only the transient overexpression of VcMYB-1 promoted anthocyanin accumulation in the green fruits. Our study can provide a basis for future research on the anthocyanin biosynthesis related MYBs in blueberry