THE EFFECT OF HEDGING ON THE VALUE OF U.S. OIL AND GAS PRODUCERS

This paper evaluates the effect of hedging on the values of 42 U.S. oil and gas producing firms from 2002 to 2006. We use a unique hand-collected data set on all linear and nonlinear hedging positions of these firms. In contrast to recent studies, we find that hedging oil price risk using nonlinear instruments, such as options, increases the value of the firm. Linear hedging contracts have little (oil contracts) or negative (gas contracts) effect on firm valuation. In addition, we find that energy price volatility negatively affects firm valuation, but has little influence on the relation between hedging activities and the value of the firm

Calretinin-expressing interneurons in the mouse spinal cord

Skin and organs in the body are innervated by primary afferents that respond to both noxious and non-noxious stimuli. The sensory information from the surrounding structures is transmitted into the dorsal horn by these afferents following their sensory modality and the region of the body that they innervate. The information is interpreted by neuronal circuits involving excitatory and inhibitory interneurons that lie in the dorsal horn of the spinal cord. This current study involves characterisation of a specific population of inhibitory neurons that are presumably involved in presynaptic inhibition towards central terminal of non-peptidergic C fibres that terminate in a complex known as synaptic glomeruli (type I) in the middle of lamina II of the dorsal horn. The inhibition is formed through axoaxonic synapses on the central axons of these primary afferent fibres. A preliminary work carried out by Dr David I Hughes using CR::eGFP mouse line found that calcium binding protein, calretinin (CR) is expressed mostly by excitatory interneurons and a small percentage by inhibitory interneurons. Electron microscopic study was performed in these animals and he found that axonal boutons originated from dorsal horn calretinin cells were presynaptic to the central axon of type I glomeruli, which belong to CMrgD afferents. He also found that these cells have islet morphology which suggested that they are inhibitory cells. The main objective of the project was to characterize a population of inhibitory CR interneurons in the superficial dorsal horn (SDH) and their synaptic connection with CMrgD primary afferent fibres. To achieve this several transgenic mouse lines that labelled inhibitory interneurons in the dorsal horn were used including lines in which Nociceptin and RorB transgenes were either expressed under the control of the regulatory elements of the Nociceptin gene or knocked into the RorB locus, respectively. Using Nociceptin::eGFP mice it was found that 93% of the cells that expressed eGFP were positive for Pax2 thus showed that these animals labelled inhibitory interneurons in the dorsal horn. In this mouse lines it was found that inhibitory CR cells in lamina II formed a band of dendrites and axons that perfectly overlapped with non-peptidergic C fibres plexus that were labelled with Isolectin B4 (IB4). The great majority of inhibitory interneurons (78%) in the SDH of Nociceptin::eGFP mice were immunoreactive for eGFP. Based on this result, Nociceptin::eGFP mice were then crossed with CRCre and Ai9 mice to allow reconstructions of individual neurons. It was found that inhibitory CR interneurons resemble islet cells and had dendrites projecting extensively in the rostrocaudal axis with a limited dorsoventral extent that arborized within lamina II. Due to a few limitations with Nociceptin::eGFP mice, this project was then continued with a knock-in mouse line, RorBeGFP mouse that also labelled inhibitory interneurons in the dorsal horn. It was found that more of lamina II inhibitory CR-immunoreactive cells were labelled in RorβeGFP mouse line than the Nociceptin::eGFP mouse, thus showed that RorBeGFP mice appeared to be a better choice for investigating the inhibitory CR cells than Nociceptin::eGFP mice. In this study it was found that inhibitory CR cells do not co-expressed other neurochemical markers of the inhibitory interneurons such as galanin, nNOS, NPY and PV. This showed that CR represent another neurochemically distinct group of inhibitory interneurons in the dorsal horn. To investigate the synaptic connection between CR islet cells with CMrgD afferents, the third part of the study was carried out using the RorBCreERT2 mouse line with tamoxifen induction. In this study, it was found that intraperitoneal injection of tamoxifen in early stage of postnatal life resulted in more labelling of cells, meanwhile less cells were labelled if tamoxifen were given at the later stage of postnatal life. Surprisingly, under optimal conditions, only a quarter of the inhibitory CR cells in lamina II were immunoreactive for tdTomato. However, the majority of tdTomato cells in the SDH are inhibitory interneurons and immunoreactive for CR, thus showed that this mouse line was highly selective for inhibitory CR cells. Using this mouse line, it was found that most of CMrgD afferents central terminals were in contact with axonal boutons of inhibitory CR cells and the excitatory synapses on the dendritic trees of inhibitory CR cells were derived from CMrgD afferents. About 40% of the inhibitory CR axonal boutons are in contact with non-peptidergic C-nociceptors and electron microscopic revealed that the axons belonged to the inhibitory CR cells formed axoaxonic synapses with CMrgD afferents. A few studies claimed there is a loss of these cells after peripheral nerve injury. However, in this study there were no loss of cells seen following sciatic nerve transection with no alteration on the rostrocaudal and dorsoventral extent of inhibitory CR cells in the affected area on RorBCreERT2; Ai9 mice. The results from this study suggest that a subset of lamina II inhibitory interneurons that express CR form axoaxonic synapses on the central boutons of type I synaptic glomeruli which belong to CMrgD afferents and they also receive excitatory inputs from these primary afferents. As a conclusion, results from this study are in parallel with the recommendation that different neurochemical populations of inhibitory neurons have distinct functional roles and also emphasize the important of presynaptic inhibition on central terminals of CMrgD primary afferents in maintaining normal somatosensation

Khat chewing in pregnant women associated with prelabor rupture of membranes, evidence from eastern Ethiopia

Introduction: prelabor rupture of membranes (PROM) is a major factor that affects pregnancy outcome. Results from previous studies have suggested that there is an association between pregnant women, khat chewing and preterm birth, but evidence of association with PROM is sparse. This study therefore aims at identifying association between khat chewing in pregnancy and premature rupture of membranes in eastern Ethiopia. Methods: A health facility-based cross-sectional study was conducted among 1688 pregnant women who came for delivery service in Harar town, Eastern Ethiopia between June to October in 2016. Data were collected using a pre-tested structured questionnaire and checklist to extract data from the medical record. The association between khat and PROM was examined using logistic regression analysis. A statistical significance was declared at p-value < 0.05. Results: Of the 1688 pregnant women who participated in the study, 397 had prelabor rupture of the membranes, representing a proportion of 23.5% [(95% CI: (21.5, 25.6%)]. Of these 397 prelabor rupture of the membranes 198 (31.53%) were from Khat chewing mothers and, 199(18.77%) were from non-khat chewing mothers. After controlling for potential confounders, the multivariable logistic regression analysis revealed the odds of PROM was 1.51 times higher among khat chewed pregnant women [AOR = 1.51; 95% CI; (1.11, 2.07)] were had no khat chewing. Conclusion: this study found a significant association between khat chewing in pregnancy and PROM. Efforts to reduce PROM need to consider prevention of khat chewing in pregnancy. A specific strategy need to protect pregnant women from khat chewing

The Functional and Familiarizing Role of Phonemes in the Description of Women in "Emraolqeis" Poem

The phoneme is considered smallest linguistic unit that is used to distinguish words from each other.  Relation between phonology and semantics placed in the context of relation between signifier and signified. And difference betwwen linguists continue until now. Some of them believe that there are functional role for phoneme in  innovative text. Whereas others believe that there is no relationship between meaning and phonem . In this article we count phonemes in Emraolqeis poem and we express presence and absence defamiliarisation in woman description woman description constitutes part of the ignorance poem. And then we try to analyze the relationship between presence and absence defamiliarisation and meaning in woman descriptions. Finally we came to the conclusion that the  phoneme functional role in poetic text . and in woman description for Emraolqeis poem the Phonemes that are associated with meaning are abundant And the phonemes that have no relationship With meaning are scant

Prevalence, risk factors and antibiogram of Escherichia coli isolated from dogs in Ambo, Gojo and Bako towns of Oromia region, Ethiopia

Dogs are a potential reservoir for Escherichia coli and other zoonotic bacterial pathogens posing the risk of infection to humans and other animals. A crosssectional study was used to collect 438 rectal swab samples from apparently healthy dogs of Ambo, Gojo, and Bako towns of West Shewa Zone with the objectives of investigating the prevalence, risk factors and antibiogram of E. coli. A questionnaire survey was administered at the household level to collect data on potential risk factors to acquire E. coli infection. Prevalence was determined by using standard bacteriological culture techniques. Further  confirmation and antimicrobial susceptibility testing of E. coli using the minimum inhibitory concentration (MIC) method were  conducted using Automated Phoenix Machine. The overall prevalence of E. coli was found to be 24.2% (95% confidence interval [CI]:20.26-28.49%). The isolation rate of E. coli was the highest in Bako 31.01%, followed by Gojo 30.99% and Ambo 18.49% towns.  Univariable and multivariable logistic regression analyses revealed that there was a significant association between E. coli prevalence and towns and Kebeles (P<0.05). However, age, sex, the presence of other domestic animals in the household, types of the housing system, educational level of the dogs’ owners, and type of feed provided to the dogs did not significantly correlate with the isolation of E. coli (P > 0.05). E. coli isolates were pan-susceptible to amikacin, ertapenem, imipenem, piperacillin-tazobactam, netilmicin, ampicillin, piperacillin, cefoxitin, ciprofloxacin, levofloxacin, and meropenem. A low level of resistance was found to aztreonam, ceftriaxone, (each 13.95%), cefazolin (22.73%), gentamicin (11.90%), and trimethoprim-sulphamethoxazole (6.97%). E. coli isolates showed multidrug resistance to aztreonam, cefazolin, ceftriaxone, gentamicin, and trimethoprim-sulphamethoxazole (14.0%). This demonstrated E. coli prevalence and moderately low antimicrobial resistance  suggests the possible risk of infection of humans. Therefore, raising public awareness about zoonotic canine disease prevention measures and good hygienic practices are essential.. Keywords: Antibiogram, Dog, Escherichia coli, Ethiopia, Prevalence, Risk facto

COVID-19 handbook for primary school children (Fun-Facts for Kids).

This eBook is designed to educate the primary school children on COVID-19 disease. The little readers will have an overview on the causative agent, symptoms of COVID-19 and how to prevent from being infected by the virus. The authors used simple language to enhance children's understanding on this matter, in a fun way. The illustrations were made in a bright, colorful images to enhance comprehension

Magnitude and causes of first-line antiretroviral therapy regimen changes among HIV patients in Ethiopia : a systematic review and meta-analysis

Background: Antiretroviral therapy (ART) has markedly decreased the morbidity and mortality due to HIV/AIDS. ART regimen change is a major challenge for the sustainability of human immunodeficiency virus (HIV) treatment program. This is found to be a major concern among HIV/AIDS patients in a resource-limited setting, where treatment options are limited. Objectives: The aim of this review is to generate the best available evidence regarding the magnitude of first-line antiretroviral therapy regimen change and the causes for regimen change among HIV patients on ART in Ethiopia. Methods: The reviewed studies were accessed through electronic web-based search strategy from PubMed Medline, EMBASE, Hinari, Springer link and Google Scholar. Data were extracted using Microsoft Excel and exported to Stata software version 13 for analyses. The overall pooled estimation of outcomes was calculated using a random-effect model of DerSimonian-Laird method at 95% confidence level. Heterogeneity of studies was determined using I2 statistics. For the magnitude of regimen change, the presence of publication bias was evaluated using the Begg's and Egger's tests. The protocol of this systematic review and meta-analysis was registered in the Prospero database with reference number ID: CRD42018099742. The published methodology is available from: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=99742. Results: A total of 22 studies published between the years 2012 and 2018 were included. Out of 22 articles, 14 articles reported the magnitude of regimen change and consisted of 13,668 HIV patients. The estimated national pooled magnitude of regimen change was 37% (95% CI: 34, 44%; Range: 15.1-63.8%) with degree of heterogeneity (I2), 98.7%; p-value < 0.001. Seventeen articles were used to identify the causes for first-line antiretroviral therapy regimen change. The major causes identified were toxicity, 58% (95% CI: 46, 69%; Range: 14.4-88.5%); TB co-morbidity, 12% (95% CI: 8, 16%; Range: 0.8-31.7%); treatment failure, 7% (95% CI: 5, 9%; Range: 0.4-24.4%); and pregnancy, 5% (95% CI: 4, 7%; Range: 0.6-11.9%). Conclusions: The original first-line regimen was changed in one-third of HIV patients on ART in Ethiopia. Toxicity of the drugs, TB co-morbidity, treatment failure, and pregnancy were the main causes for the change of the first-line regimen among HIV patients on antiretroviral therapy