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Economics and politics of shale gas in Europe
In the wake of the dramatic growth in shale gas production in the United States, interest in shale gas exploration in Europe has been driven primarily by concerns over industrial competitiveness and energy security. A number of studies have been carried out to understand the success factors underpinning the US shale gas revolution and how this success could be replicated in Europe. Most of these studies focus on the macroeconomic and energy market impact of a possible shale gas production in Europe. These studies are in general sceptical about the prospects of shale gas development relative to other gas supply options to Europe. By considering the other options available in greater detail and exploring the stochastic nature of shale gas exploration and production as they apply to production economics, we conclude that this scepticism may be overstated. Apart from political opposition that has shut down shale gas exploration in a number of European member states because of concerns over environmental risks, in some countries notably the UK, the combination of political support and a large, liberalised gas market may offer at least a plausible case for shale gas production. To properly assess the potential for shale gas though, a more rigorous, probabilistic analysis of the associated production economics will need to be carried out
A Brief Review of Probiotic Use
Probiotic therapy refers to use of live microorganisms to treat human pathological disorders such as lactose intolerance and antibiotic induced superinfections. The critical point to be consideted is whether such administered microorganisms can remain viable and multiply in the gastrointestinal tract given that their nutrient and environmental condition requirements are very exacting. In this brief review, the authors discuss the use of probiotics from a historical perspective and conclude that their use especially in form of traditional fermented food products can be justifiedthe controversy notwithstanding
A comparison of computerized versus pen-and-paper cognitive tests for monitoring electroconvulsive therapy-related cognitive side effects
Objective Cognitive side effects are a common unintended outcome of electroconvulsive therapy (ECT). Routine cognitive assessment is important for monitoring patient outcomes, although it can pose challenges in busy clinical settings. Computerized cognitive testing has advantages that can facilitate routine monitoring. This study explored the construct and criterion validity of computerized cognitive testing compared with standard pen-and-paper tests for monitoring cognition in ECT patients. Methods The study included 24 participants with major depression who received an acute course of ECT. Cognition was assessed at pretreatment and at posttreatment with 3 computerized tests from the CogState battery (International Shopping List task, One-Card Learning, and One-Back Task) and 3 conceptually matched pen-and-paper-administered neuropsychological tests. Results At pretreatment, only performance on the computer-administered test of verbal anterograde memory (International Shopping List task) was significantly correlated with the analogous pen-and-paper measure, whereas the other computerized tests were not. Of the computerized measures, only the International Shopping List task showed significant changes from pretreatment to posttreatment (P 1.0). In contrast, all the pen-and-paper-administered tests showed significant changes from pretreatment to posttreatment (P < 0.01, Cohen d range, 0.8-1.2). Pretreatment to posttreatment cognitive changes on the computerized measures were not correlated with changes on the pen-and-paper-administered tests. Conclusion Construct and criterion validity and tolerability varied between the computerized measures. The results highlighted potentially important issues related to the interpretation and utility of computerized tests in this patient population
A novel approach for targeting the left dorsolateral prefrontal cortex for transcranial magnetic stimulation using a cognitive task
Repetitive transcranial magnetic stimulation (rTMS) has the potential to be developed as a novel treatment for cognitive dysfunction. However, current methods of targeting rTMS for cognition fail to consider inter-individual functional variability. This study explored the use of a cognitive task to individualise the target site for rTMS administered to the left dorsolateral prefrontal cortex (L-DLPFC). Twenty-five healthy participants were enrolled in a sham-controlled, crossover study. Participants performed a random letter generation task under the following conditions: no stimulation, sham and active ‘online’ rTMS applied to F3 (International 10–20 System) and four standardised surrounding sites. Across all sites combined, active ‘online’ rTMS was associated with significantly reduced performance compared to sham rTMS for unique trigrams (p = 0.012), but not for unique digrams (p > 0.05). Using a novel localisation methodology based on performance outcomes from both measures, a single optimal individualised site was identified for 92% [n = 23] of participants. At the individualised site, performance was significantly poorer compared to a common standard site (F3) and both control conditions (ps < 0.01). The current results suggest that this localisation methodology using a cognitive task could be used to individualise the rTMS target site at the L-DLPFC for modulating and potentially enhancing cognitive functioning
Impact of emission mitigation on ozone-induced wheat and rice damage in India
In this study, we evaluate the potential impact of ground level ozone (O3) on rice and wheat yield in top 10 states in India during 2005. This study is based on simulated hourly O3 concentration from the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem), district-wise seasonal crop production datasets and accumulated daytime hourly O3 concentration over a threshold of 40 ppbv (AOT40)
indices to estimate crop yield damage resulting from
ambient O3 exposure. The response of nitrogen oxides
(NOx) and volatile organic compounds (VOC) mitigation
action is evaluated based on ground level O3 simulations with individual reduction in anthropogenic NOx and VOC emissions over the Indian domain. The total loss of wheat and rice from top 10 producing states in India is estimated to be 2.2 million tonnes (3.3%) and 2.05 million tonnes (2.5%) respectively. Sensitivity model study reveals relatively 93% decrease in O3-induced crop yield losses in response to anthropogenic NOx emission mitigation. The response of VOC mitigation action results in relatively small changes of about 24% decrease in O3-induced crop
yield losses, suggesting NOx as a key pollutant for
mitigation. VOC also contribute to crop yield reduction
but their effects are a distant second compared to
NOx effects
Cognitive Effects Following Offline High-Frequency Repetitive Transcranial Magnetic Stimulation (HF-rTMS) in Healthy Populations: A Systematic Review and Meta-Analysis
High-frequency repetitive transcranial magnetic stimulation (HF-rTMS) is a commonly used form of rTMS to treat neuropsychiatric disorders. Emerging evidence suggests that ‘offline’ HF-rTMS may have cognitive enhancing effects, although the magnitude and moderators of these effects remain unclear. We conducted a systematic review and meta-analysis to clarify the cognitive effects of offline HF-rTMS in healthy individuals. A literature search for randomised controlled trials with cognitive outcomes for pre and post offline HF-rTMS was performed across five databases up until March 2022. This study was registered on the PROSPERO international prospective protocol for systematic reviews (PROSPERO 2020 CRD 42,020,191,269). The Risk of Bias 2 tool was used to assess the risk of bias in randomised trials. Separate analyses examined the cognitive effects of excitatory and inhibitory forms of offline HF-rTMS on accuracy and reaction times across six cognitive domains. Fifty-three studies (N = 1507) met inclusion criteria. Excitatory offline HF-rTMS showed significant small sized effects for improving accuracy (k = 46, g = 0.12) and reaction time (k = 44, g = -0.13) across all cognitive domains collapsed. Excitatory offline HF-rTMS demonstrated a relatively greater effect for executive functioning in accuracy (k = 24, g = 0.14). Reaction times were also improved for the executive function (k = 21, g = -0.11) and motor (k = 3, g = -0.22) domains following excitatory offline HF-rTMS. The current review was restricted to healthy individuals and future research is required to examine cognitive enhancement from offline HF-rTMS in clinical cohorts
Cycloidal CT with CNN-based sinogram completion and in-scan generation of training data
In x-ray computed tomography (CT), the achievable image resolution is typically limited by several pre-fixed characteristics of the x-ray source and detector. Structuring the x-ray beam using a mask with alternating opaque and transmitting septa can overcome this limit. However, the use of a mask imposes an undersampling problem: to obtain complete datasets, significant lateral sample stepping is needed in addition to the sample rotation, resulting in high x-ray doses and long acquisition times. Cycloidal CT, an alternative scanning scheme by which the sample is rotated and translated simultaneously, can provide high aperture-driven resolution without sample stepping, resulting in a lower radiation dose and faster scans. However, cycloidal sinograms are incomplete and must be restored before tomographic images can be computed. In this work, we demonstrate that high-quality images can be reconstructed by applying the recently proposed Mixed Scale Dense (MS-D) convolutional neural network (CNN) to this task. We also propose a novel training approach by which training data are acquired as part of each scan, thus removing the need for large sets of pre-existing reference data, the acquisition of which is often not practicable or possible. We present results for both simulated datasets and real-world data, showing that the combination of cycloidal CT and machine learning-based data recovery can lead to accurate high-resolution images at a limited dose
Neurocognitive subgroups in major depressive disorder
Background: Major depressive disorder (MDD) is commonly associated with neurocognitive dysfunction. However, there remains substantial heterogeneity between patients and inconsistent findings regarding the magnitude and prevalence of specific neurocognitive deficits. This study aimed to investigate the potential for different neurocognitive subgroups in patients diagnosed with MDD. Method: Data were pooled from 4 different clinical trials that involved adults diagnosed with MDD. Neurocognitive outcomes included measures of verbal learning and memory, executive function, attention, and processing speed. Latent class analysis was conducted to examine for different subgroups based on neurocognitive profiles of performance across outcome measures. Subgroups were compared to a separate sample of age-matched adult healthy controls, across illness factors, and individual mood items on the Montgomery-Asberg Depression Rating Scale (MADRS). Results: Within the MDD cohort (N = 149), 45% of participants were considered relatively "cognitively preserved, " with the remainder "cognitively reduced" (39%) or "cognitively impaired" (16%). Verbal memory performance was significantly poorer compared to attention and processing speed only in the "cognitively impaired" subgroup. There was no association between subgroup membership and relevant illness factors, including ratings on individual MADRS items. Limitations: Data were pooled from several studies that included different neurocognitive measures and cohorts. Conclusions: Approximately half of MDD participants had no or minimal objective cognitive difficulties, and neurocognitive functioning was found generally unrelated to illness factors. Future longitudinal research is warranted to determine whether the people who are relatively cognitively impaired are at increased risk for further cognitive decline
Value-based analysis of routine pathologic septal and inferior turbinate specimens.
This article was presented at the 2012 AAO-HNSF Annual Meeting & OTO EXPO; September 9-12, 2012; Washington, DC.
Objective To determine the frequency and clinical relevance of unanticipated histopathologic results in routine sinonasal surgery and evaluate the necessity for histologic processing of nasal septal cartilage, bone, and inferior turbinate specimens. Study Design Case series with chart review. Setting Tertiary care academic medical center. Subjects and Methods A retrospective review of surgical pathology reports on adult patients undergoing sinonasal surgery during a 5-year period from 2005 to 2010 was performed. All cases with the preoperative diagnosis of sinonasal neoplasia, autoimmune disease, or directed septal biopsies were excluded from review. Results A total of 1194 pathology reports were reviewed from 1172 individual patients. This included histopathologic evaluation of 1194 septal cartilage and bone specimens and 714 inferior turbinate specimens. None of the patients had unanticipated histopathologic findings that were clinically significant. Conclusion Many surgeons obtain histopathologic diagnoses on all tissue removed from a patient. Based on our institutional case series, histopathology of the septum and inferior turbinates in routine sinonasal cases may not be necessary. A value-based approach to processing grossly unremarkable septal and turbinate tissue by waiving histologic processing and subsequent microscopic evaluation could provide significant cost savings
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