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Septic shock remains a health care concern associated with significant morbidity and mortality. The Surviving Sepsis Campaign Guidelines for Management of Sepsis and Septic Shock recommend early fluid resuscitation and antimicrobials. Beyond initial management, the guidelines do not provide clear recommendations on appropriate time to initiate vasoactive therapies and corticosteroids in patients who develop shock. This review summarizes the literature regarding time of initiation of these interventions. Clinical data regarding time of initiation of these therapies in relation to shock onset, sequence of treatments with regard to each other, and clinical markers evaluated to guide initiation are summarized. Early-high vasopressor initiation within first 6 h of shock onset is associated with lower mortality. Following norepinephrine initiation, the exact dose and timing of escalation to adjunctive vasopressor agents are not well elucidated in the literature. However, recent data indicate that timing may be an important factor in initiating vasopressors and adjunctive therapies, such as corticosteroids. Norepinephrine-equivalent dose and lactate concentration can aid in determining when to initiate vasopressin and angiotensin II in patients with septic shock. Future guidelines with clear recommendations on the time of initiation of septic shock therapies are warranted. [ABSTRACT FROM AUTHOR]

Background/Objective: There are limited data on the risks and benefits of using andexanet alfa (AA) in comparison with four-factor prothrombin complex concentrate (4F-PCC) to reverse factor Xa inhibitors (FXi) associated intracranial hemorrhage (ICH). We sought to describe our experience with AA or 4F-PCC in patients with oral FXi-related traumatic and spontaneous ICH. Methods: We conducted a retrospective review of consecutive adult patients with FXi-related ICH who received AA or 4F-PCC. FXi-related ICH cases included traumatic and spontaneous intracranial hemorrhages. Our primary analysis evaluated ICH stability on head computed tomography scan (CT), defined as a similar amount of blood from the initial scan at the onset of ICH to subsequent scans, at 6-h and 24-h post-administration of AA or 4F-PCC. For the subset of spontaneous intraparenchymal hemorrhages, volume was measured at 6-h and 24-h post-reversal. In secondary analyses, we evaluated good functional outcome at discharge, defined as a Modified Rankin Score of less than 3, and the incidence of thrombotic events after AA or 4F-PCC adminstration, during hospitalization. Results: A total of 44 patients (16 traumatic and 28 spontaneous ICH) with median age of 79 years [72–86], 36% females, with a FXi-related ICH, were included in this study. The majority of spontaneous ICHs were intraparenchymal 19 (68%). Twenty-eight patients (64%) received AA and 16 patients (36%) received 4F-PCC. There was no difference between AA and 4F-PCC in terms of CT stability at 6 h (21 [78%] vs 10 [71%], p = 0.71) and 24 h (15 [88%] vs 6 [60%], p = 0.15). In a subgroup of patients with spontaneous intraparenchymal hemorrhage, there was no difference in the degree of achieved hemostasis based on hematoma volume between AA and 4F-PCC at 6 h (9.3 mL [6.9–26.4] vs 10 mL [9.4–22.1], adjusted p = 0. 997) and 24-h (9.2 mL [6.1–18.8] vs 9.9 [9.4–21.1], adjusted p = 1). The number of patients with good outcome based on mRS on discharge were 10 (36%) and 6 (38%) in the AA and 4F-PCC groups, respectively (adjusted p = 0.81). The incidence of thromboembolic events was similar in the AA and 4F-PCC groups (2 [7%] vs 0, p = 0.53). Conclusion: In this limited sample of patients, we found no difference in neuroimaging stability, functional outcome and thrombotic events when comparing AA and 4F-PCC in patients with FXi-related ICH. Since our analysis is likely underpowered, a multi-center collaborative network devoted to this question is warranted. [ABSTRACT FROM AUTHOR]

We describe a simple method to synthesize novel 4-cyano-1-morpholin-4-yl-6,7-dihydro-5H-cyclopenta[c]pyridine-3-thione by the reaction of 3-amino-1-thioxo-1,5,6,7-tetrahydrocyclopenta[c]thiopyran-4-carbonitrile with morpholine through Dimroth rearrangement. The 1-amino-5-morpholin-4-yl-7,8-dihydro-6H-cyclopenta[d]thieno[2,3-b]pyridine-2-carboxamide, which was synthesized by two methods, was used as a versatile precursor for synthesis of new thienopyrimidines fused to cyclopenta[d]pyridine ring system. Consequently, reaction of the amino-carboxamide with diethylmalonate, triethyl orthoformate, and cycloalkanones afforded the corresponding fused pyrimidine heterocycles. On the other hand, chloroacetylation of the amino-carboxamide using chloroacetyl chloride in dioxane produced the chloroacetyl amino derivative that in turn underwent cyclocondensation upon reaction with acetic anhydride to give the chloromethyl pyrimidinone. The latter compound was subjected to react with various nitrogen nucleophiles by nucleophilic substitution reactions to yield the akyl (aryl)amino methyl pyrimidinones. Subsequently, treatment of the phenyl aminomethyl derivative with formaldehyde under Mannich conditions produced the imidazopyridothienopyrimidine ring system. Similarly, reaction of the phenyl aminomethyl pyrimidonone with chloroacetyl chloride afforded a new heterocyclic system namely, cyclopentapyridothienopyrimidopyrazine. On the other hand, reaction of the amino-carboxamide with carbon disulfide in pyridine led to the formation of oxopyrimidine thione, which was alkylated by the reaction with different α-halo carbonyl compounds. The newly synthesized compounds were fully characterized on the basis of elemental and spectral analyses. Alternatively, some of these compounds revealed promising antibacterial and antifungal activities through the in vitro screening. [ABSTRACT FROM AUTHOR]

Surface texturing of p-type monocrystalline silicon (100) is well known as one of the best methods to reduce reflection losses and to increase light trapping and light absorption probability. Pyramid surface textures play a major role in reducing the reflectance of monocrystalline silicon surfaces. In this paper, the size of pyramids formed on the surface of p-type silicon substrates and by changing the etching characteristics during the texturing process of silicon were studied and evaluated. The pyramids that formed on the crystalline silicon surface formed light traps that led to increased light absorption efficiency. The pyramid size effects on the percent reflectivity were evaluated at normal incidence and an inverse relationship between the percent reflectivity and the pyramid size was found. The size of the pyramids was controlled by controlling the texturing process by changing the concentrations of potassium hydroxide (KOH) and isopropyl alcohol (IPA) and by controlling the etching process time. In this work, the optimized etching conditions were determined as a solution prepared with 20 wt% KOH and 3 wt% IPA for wet etching at a reaction temperature of 80°C and an etching time of 40 min. The lowest value for percent reflectivity of the patterned surfaces was 9.7% and it was achieved for pyramid bases close to 4 μm as measured at a wavelength of 650 nm. [ABSTRACT FROM AUTHOR]

In this paper, we present versatile nonlinear equalizer based on support vector machine for a standard downlink LTE link. The nonlinear effects are introduced through a solid state power amplifier. The equalizer is compared with a linear RLS and nonlinear Wiener-Hammerstein (W-H) for 16QAM-MIMO-OFDM transmission, revealing improved performance at 1 Mb/s, by 3 and 2 dB in SNR, respectively, when targeting a EVM (dB) of −60 dB. SVM equalization also outperforms the Wiener-Hammerstein by 1 dB in SNR. [ABSTRACT FROM AUTHOR]

In this work, we propose Full Volterra and Sparse Volterra channels equalization algorithms for downlink LTE system. For estimation purpose, the LTE standard provides known data as pilot symbols and exploits them through a coherent detection to improve system performance. The references symbols location is similar to diamond pattern through time and frequency domain. Our goal is to show how to use the Full Volterra and Sparse Volterra equalizers over frequency domain in order to mitigate linear and nonlinear effects introduced by power amplifier and multipath channel. Downlink LTE Performances System in term of BLER, EVM (%) and Throughput versus SNR are presented and discussed. Then we compare our results with basic RLS equalizer curves. Moreover, it is shown that the Full Volterra and Sparse Volterra models can significantly reduce interferences and nonlinear effects and consequently improve the performances of LTE Downlink System. [ABSTRACT FROM AUTHOR]

Long term evolution is standardized by the 3rd Generation Partnership Project to provide a high data rate up to 100 and 50 Mbps for downlink and uplink transmission respectively and can operate in different bandwidths ranging from 1.4 up to 20 MHz. Downlink LTE system is based on the OFDMA technique and uses several enhanced techniques in order to increase the spectral efficiency and aggregate the cell throughput. The incorporated scheduling mechanisms can significantly contribute to this goal. Scheduling mechanism is the process of allocated the resources (time and frequency) to users transmitting different flows in same time. In this paper, we propose a novel scheduling algorithm for downlink transmission in LTE system. The performances of the newly scheduler are simulated and compare to the performances of three basic scheduler such as Round Robin, Proportional Fair and Max Rate. [ABSTRACT FROM AUTHOR]

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An Erratum to this paper has been published: https://doi.org/10.1134/S1068162020060060 [ABSTRACT FROM AUTHOR]

A correction to the article "Analysis of Full Volterra and Sparse Volterra Nonlinear Equalization for Downlink LTE System," that appeared in the June 3, 2016 issue is presented.