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Peering between two networks may be either settlement-free or paid. In order to qualify for settlement-free peering, large Internet Service Providers (ISPs) require that peers meet certain requirements. However, the academic literature has not yet shown the relationship between these settlement-free peering requirements and the value to each interconnecting network. We develop two models to analyze the value to each network from the most common and important requirements in the United States. Large ISPs in the U.S. often require potential settlement-free peers to interconnect at a minimum of 6-8 locations. We find that there is a substantial benefit from this requirement to the ISP, but little incremental benefit from a larger number of interconnection points. Large ISPs often require that the ratio of incoming traffic to outgoing traffic remain below approximately 2:1. In the case of two interconnecting ISPs, we find that this requirement ensures a roughly equal exchange of value. We also show that it is rational for an ISP to agree to settlement-free peering if the content provider agrees to interconnect at a specified minimum number of interconnection points and to deliver a specified minimum proportion of traffic locally, but a limit on the traffic ratio is irrational.

Internet users have suffered collateral damage in tussles over paid peering between large ISPs and large content providers. Paid peering is a relationship where two networks exchange traffic with payment, which provides direct access to each other's customers without having to pay a third party to carry that traffic for them. The issue will arise again when the United States Federal Communications Commission (FCC) considers a new net neutrality order. We first consider the effect of paid peering on broadband prices. We adopt a two-sided market model in which an ISP maximizes profit by setting broadband prices and a paid peering price. We analytically derive the profit-maximizing prices, and show that they satisfy a generalization of the well-known Lerner rule. Our result shows that paid peering fees reduce the premium plan price, increase the video streaming price and the total price for premium tier customers who subscribe to video streaming services; however, the ISP passes on to its customers only a portion of the revenue from paid peering. ISP profit increases but video streaming profit decreases as an ISP moves from settlement-free peering to paid peering price. We next consider the effect of paid peering on consumer surplus. We find that consumer surplus is a uni-modal function of the paid peering fee. The paid peering fee that maximizes consumer surplus depends on elasticities of demand for broadband and for video streaming. However, consumer surplus is maximized when paid peering fees are significantly lower than those that maximize ISP profit. However, it does not follow that settlement-free peering is always the policy that maximizes consumer surplus. The peering price depends critically on the incremental ISP cost per video streaming subscriber; at different costs, it can be negative, zero, or positive.

Objectives Therapeutic plasma exchange (TPE) is a plasmapheresis procedure whose Safety data for pediatric neuro-immunological disorders (PNID) is confined. The present research documents TPE's safety and feasibility data in these conditions. Materials & Methods The current study involved six distinct groups of patients with PNID undergoing TPE: neuromyelitis optic spectrum disorder (NMOSD), autoimmune encephalitis (AIE), acute disseminated encephalomyelitis (ADEM), multiple sclerosis (MS), Guillain-Barre syndrome (GBS), and optic neuritis (ON). This study documented complications related to each TPE process. In addition, TPE's efficacy was studied in these patients. Results The present study recorded adverse effects in 18 patients with PNID that received 121 TPE cycles: five cycles (4.13%) in MS, three (2.48%) in AIE subgroup, one (0.82%) in ADEM, and two (1.65%) in GBS. No severe complications were observed among the patients. Conclusion Patients with PNID tolerated therapeutic plasma exchange, which was a safe process. [ABSTRACT FROM AUTHOR]

Background: Breath‐holding spells (BHS) are common in infancy and early childhood and may appear like seizures. Factors such as autonomic dysfunction and iron deficiency anemia are thought to contribute to the incidence of BHS. In this study, electrocardiographic (ECG) parameters of patients with BHS were compared to those of healthy, normal children. Logistic regression and machine‐learning (ML) models were then created to predict these spells based on ECG characteristics. Methods: In this case–control study, 52 BHS children have included as the case and 150 healthy children as the control group. ECG was taken from all children along with clinical examinations. Multivariate logistic regression model was used to predict BHS occurrence based on ECG parameters. ML model was trained and validated using the Gradient‐Boosting algorithm, in the R programming language. Results: In BHS and control groups, the average age was 11.90 ± 6.63 and 11.33 ± 6.17 months, respectively (p =.58). Mean heart rate, PR interval, and QRS interval on ECGs did not differ significantly between the two groups. BHS patients had significantly higher QTc, QTd, TpTe, and TpTe/QT (all p‐values <.001). Evaluation of the ML model for prediction of BHS, fitting on the testing data showed AUC, specificity, and sensitivity of 0.94, 0.90, and 0.94 respectively. Conclusion: There are repolarization changes in patients with BHS, as the QTc, QTd, TpTe, and TpTe/QT ratio were significantly higher in these patients, which might be noticeable for future arrhythmia occurrence. In this regard, we developed a successful ML model to predict the possibility of BHS in suspected subjects. [ABSTRACT FROM AUTHOR]

This study was conducted to compare nutrient digestibility, performance and immune response of dairy cows received live and autolyzed yeast during the transition period in high ambient temperature. Cows (n = 25) were randomly divided and received a basal diet with or without live yeast or autolyzed yeast as on top three weeks pre-parturition until three weeks post-parturition. The Control group received a basal diet without yeast products; other groups received 0.5 g live yeast; 1.0 g live yeast; 10 g autolyzed yeast and 20 g/d/head autolyzed yeast. Live yeast resulted in higher nutrient digestibility compared with autolyzed yeast and the control. Methane production was the highest in autolyzed yeast and the lowest in live yeast. Average milk production was the highest in cows that received live yeast. The highest IgG level was for cows that received autolyzed yeast at a dose of 20 g/d/head. Live yeast had no significant effect, but autolyzed yeast increased the relative expression of γ-Interferon and interleukin-2 as compared with the control group. It was concluded that live yeast at a dose of 1.0 g/d/head could influence ruminal fermentation and milk production, but autolyzed yeast at a dose of 20 g/d/head could influence the immune response of dairy cows during the transition period and heat stress. [ABSTRACT FROM AUTHOR]

Background: Neuroimmunological diseases in children encompass a range of disorders that lead to neurological complications in patients due to immune responses and systemic circulating antibodies. Limited research has been conducted on therapeutic plasma exchange's efficacy and potential side effects in children with neuroimmunological diseases. Objectives: This study aimed to investigate this procedure's effectiveness and potential side effects in children afflicted by these diseases. Methods: This cross-sectional study examined a cohort of 18 children with neuroimmunological diseases who were admitted to the neurology department of Mofid Hospital over one year from March 2021 and underwent therapeutic plasma exchange. Results: The study included 18 patients, with an equal distribution of 9 females and 9 males. A total of 121 procedures were performed across 6 different disease groups: Multiple Sclerosis (22%, n = 4), Autoimmune Encephalitis (22%, n = 4), Neuromyelitis Optica Spectrum Disorder (22%, n = 4), Guillain-Barré syndrome (22%, n = 4), Acute Disseminated Encephalomyelitis (6%, n = 1), and Optic Neuritis (6%, n = 1). Following the plasma exchange, 17 patients (95%) showed immediate clinical improvement, while one patient diagnosed with optic neuritis did not respond to the treatment. During the follow-up period, 14 patients (78%) demonstrated significant improvement, one patient (6%) showed moderate improvement, and two patients (11%) exhibited mild improvement compared to their pre-plasmapheresis condition. Laboratory examinations revealed that only one patient experienced thrombocytopenia, which resolved without requiring treatment. No complications were observed during the follow-up visits for any of the patients. Conclusions: Plasma exchange is a safe procedure for children with neuroimmunological diseases and yields favorable clinical responses. [ABSTRACT FROM AUTHOR]

The natural gas treatment plant is one source of CO2 emissions into the atmosphere. To tackle this issue, it is probable to inject CO2 into the wells and it can be used for enhanced oil recovery (EOR) application. However, the main setback is the high content of water in acid gas that could be converted to hydrate at high pressure in the pipelines. In this article, two different processes (solvent extraction, stripping gas) with two different solvents mono ethylene glycol (MEG), Tri ethylene glycol (TEG), are simulated in Aspen HYSYS. The stripping gas method is more efficient in terms of energy consumption, consuming 31.8% and 56.8% less energy than solvent extraction method for MEG and TEG solvents, respectively. Hydrate formation analyses showed that applying MEG as a solvent in the stripping gas method leads to a safer operation region. Economic evaluation depicts that the stripping gas method saves the total annual cost by 22.2% compared to solvent extraction. [ABSTRACT FROM AUTHOR]

Objectives The SARS-CoV-2 pandemic is the most challenging crisis in the contemporary world. Besides severe pulmonary involvement, the disease also has several extrapulmonary manifestations, and new signs and symptoms are associated with it every dayThe present study aimed to inquire about the frequency of neurological manifestations and risk factors of COVID-19. Materials & Methods This retrospective, descriptive study included patients with neurological involvement admitted to the Alborz University of Medical Sciences academic hospitals from March 2020 to July 2020 with confirmed COVID-19 infection. The data included in the analysis were the patient's demographic information, underlying diseases, neurological manifestations, and laboratory findings. Results The study included ninety-five patients with a mean age of fiftynine. Neurological symptoms and signs were observed in 91.6% and 10.5% of the patients, respectively. The most frequently associated neurological symptoms of COVID-19 were fatigue (49.5%), headache (47.4%), and dizziness (45.3%). Furthermore, the most common neurological involvements included gait disorders (6.3%), cerebellar dysfunction (4.2%), and cerebrovascular accidents (3.15%). Positive troponin was shown to be the strongest predictor of neurological signs (OR=21, P=0.017), followed by WBC≥15,000 (OR = 20.75, P=0.018) and a history of respiratory disease (OR=7.42, P=0.007). Conclusion Neurological symptoms were observed in more than 91% of the patients, while neurological signs were present in 10.5% of the COVID-19 patients. Additionally, positive troponin, WBC≥15,000, and a history of respiratory disease were the strongest predictors of neurological signs. [ABSTRACT FROM AUTHOR]

Objective To determine the clinical and MRI characteristics of multiple sclerosis (MS) in the children and adolescents. Material & Methods In this cross-sectional study, information of 95 MS patients was obtained from the Iranian MS registry. Disease characteristics and imaging data were collected using medical records. Results Ninety-five patients including 64 female and 31 male subjects with mean age of 13.97±2.4 years (range, 8-18) years were enrolled. The most frequent signs and symptoms were ophthalmic symptoms (n=61, 64.2%), brainstem signs (n=44, 46.3%), cerebellar signs (n=32, 33.6%) and pyramidal signs (n=26, 27.3%). Blurred vision (n=21, 34.4%) was the most common ophthalmic symptom and ataxia (n=24, 75%) the most prevalent cerebellar sign. The most common brainstem signs/symptoms were motor symptoms and vertigo (each n=14, 31.8%) and the most common pyramidal sign/symptom was right upper monoparesis (n=14, 23.3%). Active demyelinating lesions were reported in brain MRI of all patients, mostly appeared as periventricular (n=91, 95.8%) and pericallosal (n=55, 57.9%) lesions. Acute demyelinating spinal lesions were presented in 38 patients (51.3%) with a prominent involvement of the cervical spine (n=33, 86.8%). Conclusion In our study, the most frequent signs and symptoms were eye symptoms, brainstem signs, cerebellar signs and pyramidal signs, respectively. Moreover, our results showed that MRI plays a critical role in the diagnostic evaluation of MS in children with presence of brain lesions in all patients and spinal lesion in a considerable portion of patients. [ABSTRACT FROM AUTHOR]