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The value of 18 F-FDG PET/CT quantitative indexes in the diagnosis of non-destructive...
Zhuyuan Si
Dongyan Lu

Zhuyuan Si

and 12 more

September 05, 2022
Rationale: Post-transplant lymphoproliferative disease (PTLD) is a serious complication after pediatric liver transplantation (pLT), which may lead to death. 18F-FDG PET/CT is rarely considered in PTLD after pLT and lacks clear diagnostic guidelines, especially in the differential diagnosis of non-destructive PTLD. The aim of this study was to find a quantifiable 18F-FDG PET/CT index to identify non-destructive PTLD after pLT. Materials and Methods: This retrospective study collected the data of patients who underwent pLT, postoperative lymph node biopsy, and 18F-FDG PET/CT at Tianjin First Central Hospital from January 2014 to December 2021. Quantitative indexes were established using lymph node morphology and the maximum standardized uptake value (SUVmax). Results: A total of 83 patients met the inclusion criteria and were included in this retrospective study. To distinguish between PTLD-negative cases and non-destructive PTLD cases, according to the receiver operating characteristic curve, [the shortest diameter of the lymph node at the biopsy site (SDL)/the longest diameter of the lymph node at the biopsy site (LDL)]*[SUVmax at the biopsy site (SUVmaxBio)/SUVmax of the tonsils (SUVmaxTon)] had the maximum area under the curve (0.923; 95% confidence interval, 0.834–1.000), and the cut-off value was 0.264 according to the maximum value of Youden’s index. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 93.6%, 94.7%, 97.8%, 85.7%, and 93.9%, respectively. Conclusions: (SDL/LDL)*(SUVmaxBio/SUVmaxTon) has good sensitivity, specificity, positive predictive and negative predictive values, and accuracy, and can be used as a good quantitative index for the diagnosis of non-destructive PTLD.
Functional Consequence and Therapeutic Targeting of Cryptic ALK Fusions (ALK fus ) in...
Makia K. Manselle
Rhonda E. Ries

Makia K. Manselle

and 6 more

September 05, 2022
Acute Myeloid Leukemia (AML) patients have a wide array of cytogenetic and molecular aberrations which can influence response to therapy. Monosomy7 (Mono7) is a rare subset within pediatric AML (prevalence of 4-5%), that is highly associated with poor outcomes. Fusions involving the ALK gene (14.3%) were exclusively identified within this high-risk cohort while absent across all other AML. Given the dismal outcomes of Mono7, we evaluated the use of crizotinib, an FDA-approved tyrosine kinase inhibitor, used to treat patients with ALK fusions. Our findings suggest that crizotinib may serve as a novel therapy for these patients.
Enhancing recombinant protein and viral vector production in mammalian cells by targe...
Nga Lao
Niall Barron

Nga Lao

and 1 more

September 05, 2022
N6–methyl adenosine (m6A) is the most abundant internal modification on eukaryotic mRNA and has been implicated in a wide range of fundamental cellular processes. This modification is regulated and interpreted by a set of writer, eraser, and reader proteins. To date, there have been no reports on the potential of mRNA epigenetic regulators to influence recombinant protein expression in mammalian cells. In this study we evaluated the potential of manipulating the expression of the m6A YTH domain-containing readers, YTHDF1, 2, and 3 to improve recombinant protein yield based on their role in regulating mRNA stability and promoting translation. Using siRNA-mediated gene depletion, cDNA over-expression and methylation-specific RNA immunoprecipitation, we demonstrate that (i) knock-down of YTHDF2 enhances (~2-fold) the levels of recombinant protein derived from GFP and EPO transgenes in CHO cells; (ii) the effects of YTHDF2 depletion on transgene expression is m6A-mediated and (iii) YTHDF2 depletion or over-expression of YTHDF1 increases viral protein expression and yield of infectious lentiviral particles (~2-3 fold) in HEK293 cells. We conclude that various transgenes can be subjected to regulation by m6A regulators in mammalian cell lines and that these findings demonstrate the utility of epi-transcriptomic-based approaches to host cell line engineering for improved recombinant protein and viral vector production.
Design of iterative methods with memory for solving nonlinear systems
Alicia Cordero
Neus Garrido

Alicia Cordero

and 3 more

September 05, 2022
In this paper, we design two parametric classes of iterative methods without memory to solve nonlinear systems, whose convergence order is four and seven, respectively. From their error equations and to increase the convergence order without performing new functional evaluations, memory is introduced in these families of different forms. That allows us to increase from four to seven the convergence order in the first family and from seven to eleven in the second one. We perform some numerical experiments with big size systems for confirming the theoretical results and comparing the proposed methods along other known schemes.
On the Scattering of a Plane Wave by a Perturbed Open Periodic Waveguide
Andreas Kirsch

Andreas Kirsch

September 05, 2022
We consider the scattering of a plane wave by a locally perturbed periodic (with respect to x_1) medium. If there is no perturbation it is usually assumed that the scattered wave is quasi-periodic with the same parameter as the incident plane wave. As it is well known, one can show existence under this condition but not necessarily uniqueness. Uniqueness fails for certain incident directions (if the wavenumber is kept fixed), and it is not clear which additional condition has to be assumed in this case. In this paper we will analyze three concepts. For the Limiting Absorption Principle (LAP) we replace the refractive index n=n(x) by n(x)+iε in a layer of finite width and consider the limiting case when ε tends to zero. This will give an unsatisfactory condition. In a second approach we require continuity of the field with respect to the incident direction. This will give the same satisfactory condition as the third approach where we approximate the incident plane wave by an incident point source and let the location of the source tend to infinity.
DETERMINATION OF A NONLINEAR COEFFICIENT IN A TIME-FRACTIONAL DIFFUSION EQUATION
Mustafa Zeki
Ramazan Tinaztepe

Mustafa Zeki

and 3 more

September 05, 2022
Direct and inverse problems for a nonlinear time fractional equation are studied. It is proved that the direct problem has a unique weak solution and the solution depends continuously on the nonlinear coefficient. Then it is shown that the inverse problem has a quasi-solution. The direct problem is solved by method of lines using an operator approach. A quasi-Newton optimization method is used for the numerical solution to the inverse problem. Tikhonov regularization is used to overcome the ill-posedness of the inverse problem. Numerical examples with noise free and noisy data illustrate applicability and accuracy of the proposed method to some extent.
The Impact of a Bulge on Haemodynamics in an Elastic Compliant Artery
VISHAKHA JADAUN

VISHAKHA JADAUN

September 05, 2022
The arterial vascular system exchanges blood gases using pulmonary capabilities. In humans, hemodynamic flows are subjected to periodic velocity modulations. Fluid mechanics and transport of blood gases play an important role in understanding how constitutive relations of the arterial system contribute to human functioning within physiological limits. Assuming the hemodynamic system as a finite dissipative system, the nonlinear evolution equation is perused to understand dynamical challenges under physiological conditions. The infinitesimal component of the vessel wall with concentric thickening in tunica media is considered as a nonaxisymmetric bulge in an elastic-compliant artery. Using the Lie group of transformations method, we discuss the implications of traveling wave solutions to describe their impact on hemodynamic flow in an elastic-compliant artery. We find that cumulative accretion of potential energy contributes to the creation of bright soliton at the apex of the bulge. The wave speed is maximum at the peak of the bulge and progressively retards with the antegrade flow.
A systematic review of circulating-free MYCN amplification status as a noninvasive an...
Wancun Zhang
Ying Liang

Wancun Zhang

and 8 more

September 05, 2022
MYCN gene plays an important role in neuroblastoma cell growth, apoptosis, differentiation, tumor infiltration, metastasis, and angiogenesis. MYCN gene amplification status in tumor tissue is one of the important clinical indicators of neuroblastoma risk. However, there are several problems in detecting the MYCN gene in tumor tissues, such as complex procedures in detection approaches, high detection costs, and difficulty in obtaining tumor tissues. Studies have shown that circulating-free MYCN gene amplification in neuroblastoma is consistent with that in tumor tissue. Circulating-free MYCN gene amplification has the advantages of high sensitivity, high specificity, simple operation, and non-invasiveness as an indicator for prognosis and recurrence of neuroblastoma. Therefore, the application and future development of circulating-free MYCN gene amplification status in the prognosis and recurrence monitoring of neuroblastoma was examined in this article.
The use of machine learning in species threat and conservation analysis
Vasco Veiga Branco
luis.correia

Vasco Veiga Branco

and 2 more

September 05, 2022
AbstractMachine learning is a growing computational field that borrows concepts and methodologies from statistics and data science to create semi-autonomous programmes capable of adapting to a multitude of problems and decision-making scenarios. With its potential in big data analysis, machine learning is particularly useful for tackling global conservation problems that often involve vast amounts of data and complex interactions between variables. In this systematic review, we summarise the use of machine learning methods in the study of species threats and conservation measures, and their emergent trends. Maximum entropy, Bayesian and ensemble methods have gained wide popularity in the past years and are now commonly used for multiple problems. Their relevance to modern conservation issues (and associated data types), their relatively simple implementation, and availability in a variety of software packages are the most likely factors to explain their popularity. Neural networks, decision trees, support-vector machines and evolutionary algorithms have been used in more specific situations, with some applications showing promise in dealing with increasingly complex data and scenarios.
Positivity rate, risk factors and symptom characteristics of influenza virus in a ter...
Jiaxiang Wan
Ruxuan Zhang

Jiaxiang Wan

and 1 more

September 06, 2022
Background: Following the Coronavirus disease (COVID-19) pandemic, new changes in the transmission of various pathogens have occurred. The environmental changes influenced by the COVID-19 pandemic have affected the flow of human society and the survival environment of other microorganisms. The prevalence of influenza viruses has also changed under this selection pressure. Objective: To investigate the influenza virus’s prevalence, risk factors and symptom characteristics during the outbreak of COVID-19. Methods: Samples and data were collected from outpatients requiring respiratory virus tests in a tertiary hospital. Throat swabs were tested in the immunocolloidal gold method. Characteristics of influenza A and B compared before and after the outbreak of COVID-19. Results: The dominant virus strain in 2020-2022 has gradually changed from influenza A to influenza B. Influenza A is mainly prevalent in 0 to 20 years old (P < 0.05), and influenza B is dominant in all age groups. Most of the patients with positive results were from paediatrics and presented in fever clinics (P < 0.05); Most of the patients were diagnosed with fever and upper respiratory tract infection (P < 0.05). Conclusion: The influenza virus’s positive rate, risk factors and symptom characteristics have changed compared to previous years. It means the epidemic prevention measures have greatly affected the prevalence of the influenza virus since the outbreak of COVID-19.
A power equalization RF-PWM method with third and fifth harmonic elimination
Haoyang Fu
Qiang Zhou

Haoyang Fu

and 3 more

September 05, 2022
To reduce the power loss of the SMPA unit, this paper proposes a power equalization RF-PWM method with third and fifth harmonic elimination. Based on the third and fifth harmonic cancellation, this method achieves output power equalization of SMPA by controlling the width of 3-level sub-pulses to be the same. Moreover, the equalization of each switch transistor is realized by outphasing architectures. Finally, the feasibility of the method is verified by simulation results. For QPSK and 16QAM signals with a carrier frequency of 200 MHz, the proposed method achieves the same output power of each SMPA unit.
Prodromes predict attacks of Hereditary Angioedema: results of a prospective Study
Avner Reshef
   Dr. Iris Leibovich-Nassi

Avner Reshef

and 2 more

August 12, 2022
Prodromes predict attacks of Hereditary Angioedema: results of a prospective StudyTo the Editor,Hereditary Angioedema (HAE) is a lifetime disease characterized by repetitive bouts of tissue edema.1 Early signs, symptoms and perceptions (prodromes) are manifested by subjective and objective signals, preceding attacks by several hours.2-3 Using an new HAE-specific instrument, we have recently shown that patients can identify prodromes and able to predict oncoming attacks.4 However, that study was retrospective, which might have been affected by recall bias.In the present study a cohort of 48 HAE patients prospectively reported four events of prodromes followed by attack, attacks not preceded by a prodrome and incidents with only a prodrome. Pre-defined domains (clusters of body locations) and scalable dimensions (pain, severity, impairment and functionality), time of onset and termination were assessed in each episode.3-4 (Statistical methods are described in the supplementary data ). The study was approved by the ethics committees of Tel-Aviv University, Sheba Medical Center and Barzilai Medical center. All patients signed an informed-consent form. Mean age was 35.25 years (SD ±16.4), Median 30.0 (age range 10-70) and 27 (56.25%) were females. Mean age of onset was 8.3 years and age at diagnosis 10.9 years (2.7 years diagnostic gap) (Table S1 ).We received reports on 119 prodromes and 192 attacks. The majority experienced a prodrome before at least one of their attacks, and 64% affirmed that they can predict an oncoming attack by having a prodrome.(Table S1) .Significant differences were found between prodromes and attacks across all dimensions of the predefined clusters of body locations. Statistical analysis verified that prodromes could be discriminated from attacks for all parameters. (Table 1) Positive correlations were found between the same attributes of prodromes and attacks, most notably in the abdominal and extremity clusters (Table S2, Fig S1A-E) . Mean duration of prodromes was significantly shorter than attacks, and prodromes overlapped the attack in 24.3% of cases. The predictive power analysis indicates that individuals who experience a prodrome had higher risk for having an attack in the same region. Sensitivity of the prodrome as a predictor of attack was 95% to 99%, and specificity 18% to 64%. (Table 2).HAE prodromes represents a continuity of pathophysiologic events, initiated by the activation of the bradykinin-forming cascade and ending with a breach in vascular endothelial integrity.2, 5(Fig S2 ) In this study we aimed to capture the critical elements of prodromes and their association with consequent attacks and evaluate their predictive power as an early warning sign.2-4 The HAE-EPA instrument reliably captures patient’s experience by using the same metrics, and the prospective design better reflects patients’ experience in real-time, which may have been missed in our previous study.The study shades light on the predictive value of prodromes as forecasters of attacks.2-4 It affirms that patients can clearly distinguish prodromes from attacks. The positive correlations support our basic assumption that prodromes could predict attack location and severity, which is particularly germane in the abdomen. In most cases a high intensity attack was predated by a high intensity prodrome. This substantiate our observation on inter-personal differences between subjects4 Mean disease duration of the cohort (27 years) may surmise that the study subjects were experienced patients, who could recognize early pre-attack cues.Treating oncoming attack at the prodromal stage may enhance resolution of attacks.6, 7 Therefore; experienced patients can use prodromes as an efficient strategy in managing attacks by employing early interventions. Such approach can apply in other diseases with relapsing-remitting pattern and advance the concept of prodrome-triggered intervention.8In conclusion , the study ascertained that HAE patients can distinguish prodromes from attacks and a prodrome may predict attack in the same location. Having a prodrome increase the likelihood of subsequent attack, alerting the patients and assisting in early initiation of therapy.Table 1: Within-subject differences between prodrome and attacks
Acquired Amegakaryocytic Thrombocytopenic Purpura (AAMT) Case Series and a single cen...
Samah Kohla
Shehab  Fareed

Samah Kohla

and 9 more

September 05, 2022
Acquired Amegakaryocytic Thrombocytopenia is a rare hematologic condition, with <50 cases reported. It is characterized by severe thrombocytopenia with complete absence or severe reduction of megakaryocytes in the bone marrow with otherwise normal hematopoiesis. Its mechanism is not fully understood but is suggested to be related to anti-thrombopoietin antibodies.
Malignant Gastro-Intestinal Stromal Tumours in a middle-aged male -- A diagnostic cha...
Shravya  Kalagadda
Sai Kiran Kuchana

Shravya Kalagadda

and 5 more

September 05, 2022
Gastro-intestinal Stromal Tumors (GISTs), soft tissue sarcomas of the gastrointestinal tract, represent the most frequent malignant gastrointestinal tumors of the subepithelial lesions (SELs) and of mesenchymal gastrointestinal tract. The size of the tumour and its mitotic activity were initially used as risk indicators in determining the prognosis.
Ab initio calculation of ground and low excited state spectroscopic data and transiti...
guosen Wang
XinGuan Tan

guosen Wang

and 3 more

September 05, 2022
In this paper, the potential energy curves of the Λ-S and Ω states of SBr+ are reported for the first time, and the spectrum data of some low excited bound states are obtained. The differences in the spectrum properties of main group molecules and SBr+ were compared and analyzed, providing a sufficient theoretical basis for the subsequent study of main group molecules. The phenomenon of avoided crossing that occurs in the Ω state is analyzed, and finally it is concluded that this phenomenon mainly occurs in the energy region between 20000 cm-1 and 40000 cm-1. Potential transitions in the Ω state capable of achieving laser cooling of SBr+ are explored. The Franck-Condon factor, radiation lifetime and Einstein coefficient between Χ3Σ-0+ and 21Σ+0+ are calculated. From the calculation results, we concluded that direct laser cooling of SBr+ is not feasible. What we have studied in this paper provides a theoretical basis for subsequent computational exploration of the spectrum properties of SBr+.
The resilience of cryptocurrency market efficiency to COVID-19 shock

Leonardo H S Fernandes

and 4 more

September 05, 2022
We examine the price disorder and market efficiency of five cryptocurrencies (Bitcoin, BNB, Cardano, Ethereum, and XRP) before and during COVID-19 pandemic period. Using permutation entropy and Fisher information measure (FIM), we construct the Shannon-Fisher causality plane (SFCP) to map these cryptocurrencies and their respective locations in a two-dimensional plane and then apply sliding time window approach to study the temporal evolution of efficiency. All cryptocurrencies exhibit high but slightly varying informational efficiency during both periods. Cardano is the most efficient. These results might point to the increasing maturity and lower potential for price predictability, which matter to cryp-tocurrencies usage for liquidity risk diversification strategy.
Extremal values of vertex--degree--based topological indices over fluoranthene-type b...
fengwei Li
Qingfang Ye

fengwei Li

and 2 more

September 05, 2022
Let $G$ be a graph with $n$ vertices. A vertex–degree–based topological index is defined from a set of real numbers $\{\psi_{ij}\}$ as $$TI(G)=\sum_{1\leq i\leq j\leq n-1}m_{ij}\psi_{ij},$$ where $m_{ij}$ is the number of edges of $G$ connecting a vertex of degree $i$ with a vertex of degree $j$. Many of the well–known topological indices are particular cases of this expression, including all Randi\’{c}-type connectivity indices. In this work we determine extremal values for $TI$ over the set of fluoranthene–type benzenoid systems with a fixed number of edges. The main idea consists in constructing fluoranthene–type benzenoid systems with maximal number of inlets in $\Gamma_{m}$ which have simultaneously minimal number of hexagons, where $\Gamma_{m}$ is the set of fluoranthene–type benzenoid systems with exactly $m(m\geq19)$ edges.
Ascending Aortic Length and Type A Dissection: A Propensity Score-Matched Cohort Anal...
Gregory Boyajian
Nikhil K. Prasad

Gregory Boyajian

and 11 more

September 04, 2022
Background: Little information is available regarding the relationship between ascending aortic length and acute aortic events. We aim to evaluate whether patients with acute type A aortic dissection (ATAAD) exhibit differential aortic measurements compared to control patients. Methods: Data were collected on patients with ATAAD and control patients who received imaging for unrelated conditions. Propensity score matching was conducted using age, sex, race, body surface area, and hypertension in the logistic model. After matching, 67 patients remained in each group. Aortic morphometry was assessed via computed tomographic angiography. Ascending aortic length was defined as the centerline distance between the sinotubular junction (STJ) and the origin of the brachiocephalic trunk. Results: The mean ascending aortic length was 76.9 ± 15.7 mm (range 36.8 to 115.0 mm) for patients with ATAAD and was 62.0 ± 10.7 mm (range 34.0 to 87.8 mm) for control patients, which was a significant difference (t=-6.4, P<0.001). ATAAD patients had greater diameter at STJ (median: 41.6 vs 30.2 mm, z=7.5, P<0.001) and diameter at PAB (median: 42.3 vs 32.2 mm, z=6.8, P<0.001) compared with controls. A maximum ascending aortic diameter >5.5 cm (at either the PAB or STJ) was present in 12 of 67 cases (18%) and 0 of 67 controls (P<0.001). Conclusions: Ascending aortic length is significantly greater in patients who experienced ATAAD compared to matched controls. Elongation of the aorta may play a role in the pathogenesis of ATAAD, and assessment of ascending aortic length may be valuable as a predictive marker for aortic events.
Letter to the Editor: The routine use of platelet function tests in elective coronary...
Kantash Kumar
Rohit Kumar

Kantash Kumar

and 1 more

September 04, 2022
A document by Kantash Kumar. Click on the document to view its contents.
Coronary Artery Involvement in Type A Aortic Dissection: Fate of the Coronaries
Matti Jubouri
Fatima Kayali

Matti Jubouri

and 7 more

September 04, 2022
Background: Type A aortic dissection (TAAD) involves a tear in the intimal layer of the thoracic aorta proximal to the left subclavian artery, and hence, carries a high risk of mortality and morbidity and requires urgent intervention. This dissection can extend into the main coronary arteries. Coronary artery involvement in TAAD can either be due to retrograde extension of the dissection flap into the coronaries or compression and/or blockage of these vessels by the dissection flap, possibly causing myocardial ischaemia. Due to the emergent nature of TAAD, coronary involvement is often missed during diagnosis, thereby delaying the required intervention. Aims: The main scope of this review is to summarise the literature on the incidence, mechanism, diagnosis, and treatment of coronary artery involvement in TAAD. Methods: A comprehensive literature search was performed using multiple electronic databases, including PubMed, Ovid, Scopus and Embase, to identify and extract relevant studies. Results: Incidence of coronary artery involvement in TAAD was seldom reported in the literature, however, some studies have described patients diagnosed either preoperatively, intraoperatively following aortic clamping, or even during autopsy. Among the few studies that reported on this matter, the treatment choice for coronary involvement in TAAD was varied, with the majority revascularizing the coronary arteries using coronary artery bypass grafting or direct local repair of the vessels. It is well-established that coronary artery involvement in TAAD adds to the already high mortality and morbidity associated with this disease. Lastly, the right main coronary artery was often more implicated than the left. Conclusion: This review reiterates the significance of an accurate diagnosis and timely and effective interventions to improve prognosis. Finally, further large cohort studies and longer trials are needed to reach a definitive consensus on the best approach for coronary involvement in TAAD.
Recipient Type A Aortic Dissection After Orthotopic Heart Transplantation
Oguz Konukoglu
Ali Dogan

Oguz Konukoglu

and 4 more

September 04, 2022
Very few aortic dissections have been published following a heart transplant. Most of these have been reported as donor aortic dissections. Recipient aortic dissection is extremely rare. Here, surgical treatment of chronic Stanford type A recipient aortic dissection in a 40-year-old patient who underwent an orthotopic heart transplant 10 years ago will be discussed in the light of the literature.
COMMENTARY OUTCOME OF PERMANENT PACEMAKER IMPLANTATION IN TRANSCATHETER OR SURGICAL A...
Antonio Totaro
Antonio Calafiore

Antonio Totaro

and 3 more

September 04, 2022
Despite advances in technologies and clinical experience, conduction disorders, after TAVR or SAVR, represent the weak point of these procedures, requiring permanent pacemaker implantation (PPI) till 37.7% of patients in TAVR recipients. The role of PPI in TAVR and SAVR remains controversial in mid- and long-term outcomes. Indeed, many studies have been published with contradictory results, leaving doubts rather than certainties.
Water vapor adsorption on various rank coals: Equilibrium, thermodynamics and kinetic...
Zhenjian Liu
Chao Pu

Zhenjian Liu

and 4 more

September 04, 2022
Four coal samples of different rank were fully characterized with gas (N2 and CO2) sorption and FTIR methods. Then measurements of both equilibrium and kinetics of water vapor adsorption were undertaken at elevated temperatures. Equilibrium and kinetic data were fitted by the modified BET model and the unipore model, respectively. The corresponding thermodynamics, as well as the diffusion activation energy were estimated. The results demonstrate that water vapor adsorption depends on surface chemistry but unrelated to pore structure, because the pore space is not completely filled by water molecules even at saturation pressure. The monolayer capacity decreases with increasing coal rank. Moreover, water vapor needs lower work to attain equilibrium on higher-ranked coal. Also, the binding affinity of water molecule with primary sites is stronger than secondary sites. Furthermore, the diffusion coefficient decreases with coal rank, and the diffusion activation energy for high-volatile bituminous is the highest.
Booms in commodities price: assessing disorder and similarity overeconomic cycles    

Leonardo HS Fernandes

and 3 more

September 05, 2022
This paper provides an overview of the commodities market, considering three relevant attributes: predictability, similarity, and efficiency. We examine the monthly spot and futures prices time series for 22 commodities from January 1984 until January 2022 with 457 observations. We estimate the permutation entropy (í µí°¸íµí°¸í µí±) and Fisher information measure í µí°¹ í µí± using the Bandt & Pompe method (BPM). We employ the value of these two complexity measures to construct the Shannon-Fisher Causality Plane (SFCP), which allows us to evaluate the disorder and assess the randomness present in the monthly spot and futures prices time series for these commodities. Moreover, we apply í µí°¸íµí°¸í µí± and í µí°¹ í µí± to classify the commodities using complexity hierarchy. We find that the commodities that are located farther from the random ideal position (í µí°¸íµí°¸í µí± = 1, í µí°¹ í µí± = 0) in the SFCP, such as Natural gas, Europe; Iron ore, cfr spot, and Potassium chloride are marked by lower entropy, higher predictability and lower efficiency. In contrast, the commodities that are located near the random ideal position (í µí°¸íµí°¸í µí± = 1, í µí°¹ í µí± = 0) in the SFCP, such as Crude oil-Brent; Crude oil-average, and Silver are characterized by higher entropy, lower predictability and higher efficiency. The K-means algorithm and the hierarchical cluster grouped commodities into only three distinct groups, which is a strong indication that commodity prices have very similar behaviour.
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