358 research outputs found
The impacts of carbon pricing on maritime transport costs and their implications for developing economies
We provide an in-depth review of the extant literature on the impact a maritime carbon pricing measure might have on maritime transport costs. First, we analyse the relative importance of the determinants of maritime transport costs for trade and economic development, and secondly assess the transmission channels and economic effects of a carbon price on maritime transport costs. We argue that the introduction of a carbon price has a limited impact on total maritime transport costs for the average country. However, Small Island Developing States and Least Developed Countries are more likely to be negatively impacted by such a measure in terms of maritime transport costs as we provide novel evidence that the relationship between per unit transport costs and trade flows is negative and elastic at least for the case of Pacific Small Island Developing States
Dephasing effects on stimulated Raman adiabatic passage in tripod configurations
We present an analytic description of the effects of dephasing processes on
stimulated Raman adiabatic passage in a tripod quantum system. To this end, we
develop an effective two-level model. Our analysis makes use of the adiabatic
approximation in the weak dephasing regime. An effective master equation for a
two-level system formed by two dark states is derived, where analytic solutions
are obtained by utilizing the Demkov-Kunike model. From these, it is found that
the fidelity for the final coherent superposition state decreases exponentially
for increasing dephasing rates. Depending on the pulse ordering and for
adiabatic evolution the pulse delay can have an inverse effect.Comment: 13 pages; 9 figures; Accepted for publication Physical Review
Interactions encountered inside dual-species biofilms formed by Salmonella Typhimurium and autochthonous microbiota recovered from leafy salads on stainless steel
In the present study, the ability of bacteria isolated from leafy salads to affect biofilm formation by Salmonella Typhimurium (ST), when all these were cultured together on stainless steel (SS) coupons, was investigated. To achieve this, isolates recovered from either rocket or spinach salads were left to form mixed culture dual-species biofilms with ST on SS coupons immerged in: (i) LB medium, (ii) rocket sterile extract, and (iii) spinach sterile extract, at 20Ā°C
Greek high phenolic early harvest extra virgin olive oil reduces the over-excitation of information-flow based on dominant coupling mode model in patients with mild cognitive impairment: an EEG resting-state validation approach
Background:Extra virgin olive oil (EVOO) constitutes a natural compound with high protection over cognitive function that could positively alter brain dynamics and the mixture of within and between-frequency connectivity. Objective:The balance of cross-frequency coupling over within-frequency coupling can build a nonlinearity index (NI) that encapsulates the over-excitation of information flow between brain areas and across experimental time. The present study investigated for the very first time how the Greek High Phenolic Early Harvest Extra Virgin Olive Oil (HP-EH-EVOO) versus Moderate Phenolic (MP-EVOO) and Mediterranean Diet (MeDi) intervention in people with mild cognitive impairment (MCI) could affect their spontaneous EEG dynamic connectivity. Methods:Forty-three subjects (14 in MeDi, 16 in MP-EVOO, and 13 in HP-EH-EVOO) followed an EEG resting-state recording session (eyes-open and closed) before and after the treatment. Following our dominant coupling mode model, we built a dynamic integrated dynamic functional connectivity graph that tabulates the functional strength and the dominant coupling mode model of every pair of brain areas. Results:Signal spectrum within 1ā13 Hz and theta/beta ratio have decreased in the HP-EH-EVOO group in the eyes-open condition. The intervention improved the FI D oCM across groups and conditions but was more prominent in the HP-EH-EVOO group (pā< ā0.001). Finally, we revealed a significant higher post-intervention reduction of NI (ĪNITotalāandāĪ± ) for the HP-EH-EVOO compared to the MP-EVOO and MeDi groups (pā< ā0.0001). Conclusion:Long-term intervention with HP-EH-EVOO reduced the over-excitation of information flow in spontaneous brain activity and altered the signal spectrum of EEG rhythms
Drug-disease Graph: Predicting Adverse Drug Reaction Signals via Graph Neural Network with Clinical Data
Adverse Drug Reaction (ADR) is a significant public health concern
world-wide. Numerous graph-based methods have been applied to biomedical graphs
for predicting ADRs in pre-marketing phases. ADR detection in post-market
surveillance is no less important than pre-marketing assessment, and ADR
detection with large-scale clinical data have attracted much attention in
recent years. However, there are not many studies considering graph structures
from clinical data for detecting an ADR signal, which is a pair of a
prescription and a diagnosis that might be a potential ADR. In this study, we
develop a novel graph-based framework for ADR signal detection using healthcare
claims data. We construct a Drug-disease graph with nodes representing the
medical codes. The edges are given as the relationships between two codes,
computed using the data. We apply Graph Neural Network to predict ADR signals,
using labels from the Side Effect Resource database. The model shows improved
AUROC and AUPRC performance of 0.795 and 0.775, compared to other algorithms,
showing that it successfully learns node representations expressive of those
relationships. Furthermore, our model predicts ADR pairs that do not exist in
the established ADR database, showing its capability to supplement the ADR
database.Comment: To appear at PAKDD 202
Digital biomarker-based individualized prognosis for people at risk of dementia
Background: Research investigating treatments and interventions for cognitive decline fail due to difficulties in accurately recognizing behavioral signatures in the presymptomatic stages of the disease. For this validation study, we took our previously constructed digital biomarker-based prognostic models and focused on generalizability and robustness of the models. Method: We validated prognostic models characterizing subjects using digital biomarkers in a longitudinal, multi-site, 40-month prospective study collecting data in memory clinics, general practitioner offices, and home environments. Results: Our models were able to accurately discriminate between healthy subjects and individuals at risk to progress to dementia within 3 years. The model was also able to differentiate between people with or without amyloid neuropathology and classify fast and slow cognitive decliners with a very good diagnostic performance. Conclusion: Digital biomarker prognostic models can be a useful tool to assist large-scale population screening for the early detection of cognitive impairment and patient monitoring over time
Current trends in the cardiovascular clinical trial arena (I)
The existence of effective therapies for most cardiovascular disease states, coupled with increased requirements that potential benefits of new drugs be evaluated on clinical rather than surrogate endpoints, makes it increasingly difficult to substantiate any incremental improvements in efficacy that these new drugs might offer. Compounding the problem is the highly controversial issue of comparing new agents with placebos rather than active pharmaceuticals in drug efficacy trials. Despite the recent consensus that placebos may be used ethically in well-defined, justifiable circumstances, the problem persists, in part because of increased scrutiny by ethics committees but also because of considerable lingering disagreement regarding the propriety and scientific value of placebo-controlled trials (and trials of antihypertensive drugs in particular). The disagreement also substantially affects the most viable alternative to placebo-controlled trials: actively controlled equivalence/noninferiority trials. To a great extent, this situation was prompted by numerous previous trials of this type that were marked by fundamental methodological flaws and consequent false claims, inconsistencies, and potential harm to patients. As the development and use of generic drugs continue to escalate, along with concurrent pressure to control medical costs by substituting less-expensive therapies for established ones, any claim that a new drug, intervention, or therapy is "equivalent" to another should not be accepted without close scrutiny. Adherence to proper methods in conducting studies of equivalence will help investigators to avoid false claims and inconsistencies. These matters will be addressed in the third article of this three-part series
HUWE1 E3 ligase promotes PINK1/PARKINindependent mitophagy by regulating AMBRA1 activation via IKKa
The selective removal of undesired or damaged mitochondria by autophagy, known as mitophagy, is crucial for cellular homoeostasis, and prevents tumour diffusion, neurodegeneration and ageing. The pro-autophagic molecule AMBRA1 (autophagy/beclin-1 regulator-1) has been defined as a novel regulator of mitophagy in both PINK1/PARKIN-dependent and -independent systems. Here, we identified the E3 ubiquitin ligase HUWE1 as a key inducing factor in AMBRA1-mediated mitophagy, a process that takes place independently of the main mitophagy receptors. Furthermore, we show that mitophagy function of AMBRA1 is post-translationally controlled, upon HUWE1 activity, by a positive phosphorylation on its serine 1014. This modification is mediated by the IKKĪ± kinase and induces structural changes in AMBRA1, thus promoting its interaction with LC3/GABARAP (mATG8) proteins and its mitophagic activity. Altogether, these results demonstrate that AMBRA1 regulates mitophagy through a novel pathway, in which HUWE1 and IKKĪ± are key factors, shedding new lights on the regulation of mitochondrial quality control and homoeostasis in mammalian cells
Reversible Keap1 inhibitors are preferential pharmacological tools to modulate cellular mitophagy
Mitophagy orchestrates the autophagic degradation of dysfunctional mitochondria preventing their pathological accumulation and contributing to cellular homeostasis. We previously identified a novel chemical tool (hereafter referred to as PMI), which drives mitochondria into autophagy without collapsing their membrane potential (ĪĪØm). PMI is an inhibitor of the protein-protein interaction (PPI) between the transcription factor Nrf2 and its negative regulator, Keap1 and is able to up-regulate the expression of autophagy-associated proteins, including p62/SQSTM1. Here we show that PMI promotes mitochondrial respiration, leading to a superoxide-dependent activation of mitophagy. Structurally distinct Keap1-Nrf2 PPI inhibitors promote mitochondrial turnover, while covalent Keap1 modifiers, including sulforaphane (SFN) and dimethyl fumarate (DMF), are unable to induce a similar response. Additionally, we demonstrate that SFN reverses the effects of PMI in co-treated cells by reducing the accumulation of p62 in mitochondria and subsequently limiting their autophagic degradation. This study highlights the unique features of Keap1-Nrf2 PPI inhibitors as inducers of mitophagy and their potential as pharmacological agents for the treatment of pathological conditions characterized by impaired mitochondrial quality control
Geriatric pharmacotherapy : optimisation through integrated approach in the hospital setting
Since older patients are more vulnerable to adverse drug-related events, there is a need to ensure appropriate prescribing in these patients in order to prevent misuse, overuse and underuse of drugs. Different tools and strategies have been developed to reduce inappropriate prescribing; the available measures can be divided into medication assessment tools, and speciļ¬c interventions to reduce inappropriate prescribing. Implicit criteria of inappropriate prescribing focus on appropriate dosing, search for drug-drug interactions, and increase adherence. Explicit criteria are consensus-based standards focusing on drugs and diseases and include lists of drugs to avoid in general or lists combining drugs with clinical data. These criteria take into consideration differences between patients, and stand for a medication review, by using a systematic approach. Different types of interventions exist in order to reduce inappropriate prescribing in older patients, such as: educational interventions, computerized decision support systems, pharmacist-based interventions, and geriatric assessment. The effects of these interventions have been studied, sometimes in a multifaceted approach combining different techniques, and all types seem to have positive effects on appropriateness of prescribing. Interdisciplinary teamwork within the integrative pharmaceutical care is important for improving of outcomes and safety of drug therapy. The pharmaceutical care process consists offour steps, which are cyclic for an individual patient. These steps are pharmaceutical anamnesis, medication review, design and follow-up of a pharmaceutical care plan. A standardized approach is necessary for the adequate detection and evaluation of drug-related problems. Furthermore, it is clear that drug therapy should be reviewed in-depth, by having full access to medical records, laboratory values and nursing notes. Although clinical pharmacists perform the pharmaceutical care process to manage the patientās drug therapy in every day clinical practice, the physician takes the ultimate responsibility for the care of the patient in close collaboration with nurses
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