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Rajesh N Janapala,1 Laxmaiah Manchikanti,2– 4 Mahendra R Sanapati,5,6 Srinivasa Thota,5 Alaa Abd-Elsayed,7 Alan D Kaye,8,9 Joshua A Hirsch10 1School of Medicine and Health Sciences, George Washington University, Washington, DC, USA; 2Pain Management Centers of America, Paducah, KY, USA; 3Anesthesiology and Perioperative Medicine, University of Louisville, Louisville, KY, USA; 4Department of Anesthesiology, School of Medicine, LSU Health Sciences Center, Shreveport, LA, USA; 5Pain Management Centers of America, Evansville, IN, USA; 6Anesthesiology and Research, School of Medicine, LSU Health Sciences Center, Shreveport, LA, USA; 7UW Health Pain Services, and Anesthesiology, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA; 8Departments of Anesthesiology and Pharmacology, Toxicology, and Neurosciences, LSU Health Sciences Center, Shreveport, LA, USA; 9Ochsner Shreveport Hospital and Pain Clinic Feist-Weiller Cancer Center, Shreveport, LA, USA; 10Neurointerventional Radiology and Spine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USACorrespondence: Laxmaiah ManchikantiPain Management Centers of America, 67 Lakeview Drive, Paducah, KY, 42001, USATel +1 270 554 8373Fax +1 270 554 8987Email drlm@thepainmd.comPurpose: The objective of the systematic review and meta-analysis is to evaluate the efficacy of radiofrequency neurotomy as a therapeutic lumbar facet joint intervention.Patients and Methods: Utilizing the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist, a systematic review and meta-analysis was performed. A comprehensive literature search of multiple data sources from 1966 to September 2020 including manual searches of bibliography of known review articles was performed. The inclusion criteria were based on the selection of patients with chronic low back pain with diagnosis confirmed based on controlled diagnostic blocks and with the publication of at least 6 months of results of appropriate outcome parameters. Quality assessment of the trials was performed with Cochrane review criteria and interventional pain management techniques-quality appraisal of reliability and risk of bias assessment (IPM-QRB). The level of evidence of effectiveness is classified at five levels ranging from Level I to Level V. The primary outcome measure was a significant reduction in pain, eg, short term (up to 6 months) and long term (more than 6 months). The secondary outcome measure was an improvement in functional status.Results: A total of 12 randomized controlled trials (RCTs) met the inclusion criteria for evaluating the efficacy of lumbar radiofrequency neurotomy. Radiofrequency neurotomy showed Level II evidence for efficacy for both the short term and long term.Conclusion: This systematic review of the assessment of the efficacy of radiofrequency neurotomy in managing chronic low back pain was based on the inclusion of 12 RCTs with a diagnostic block and at least 6 months of follow-up results that showed Level II evidence for both short-term and long-term improvement.Keywords: diagnostic facet joint nerve blocks, facet joint pain, facet joint nerve blocks, randomized trials, radiofrequency neurotomy, systematic review, meta-analysis

We report a detailed study on the orientation dependent growth characteristics, electronic structure, transport, magnetic, and vibrational excitations in atomically flat interfaces of [ La 0.7 Sr 0.3 MnO 3 / LaNiO 3 ] 10 superlattices (SLs) coherently grown on (001/011/111)- SrTiO 3 substrates by the pulsed laser deposition technique. X-ray reflectometry confirms the periodic superlattice stacks from the Kiessig interference fringes and well-defined even interfaces between the nickelate and manganite layers. A complex local atomic environment across the interfaces was noticed, yet trivalent La, divalent Sr, and mixed valent Ni 2 + / 3 + and Mn 3 + / 4 + electronic states prevail at the core level with enhanced relative intensity ratio of the Mn ions in the superlattices grown on (111) oriented SrTiO 3 substrates as compared to those grown on (001) and (011) oriented SrTiO 3. The temperature (5 ≤ T ≤ 300 K) dependence of electrical resistivity ρ (T) analysis reveals 3D variable range hopping model [ ρ (T) = ρ 0 exp ⁡ (T 0 / T) (1 / 4) ] with large magnitude of hopping energies (≥ 40 meV) for the SL-111 system associated with the high energy gap developed by the accumulation of disorderness in the individual constituents of polar layers. Moreover, all SL systems exhibit reduced ferromagnetic ordering temperatures (67 ≤ T C ≤ 110 K) with a low-temperature anomaly (11.4 ≤ T ∗ ≤ 22 K) and a substantial enhancement in the effective exchange interaction ( J e f f ∼ 3.52 meV) having altered ground state-spin configuration S ∼ 1 / 2 different from S = 3 / 2 of La 0.75 Sr 0.25 MnO 3. Nevertheless, the SL-011 system exhibits large anisotropy field H K ∼ 18 kOe and cubic anisotropy constant K 1 ∼ 9.3 × 10 3 J / m 3 in comparison to the other two orientations. The second order two-phonon interaction driven by the local polaronic distortion causes significant changes in the vibrational excitations of the investigated system. Nonetheless, most of the Raman modes follow the substrate-induced, highly oriented epitaxial growth pattern except for two modes ν 4 (326 cm − 1 ) and ν 8 (728 cm − 1 ), which slightly differ in the case of SL-111 superlattices. [ABSTRACT FROM AUTHOR]

We report an experimental investigation of the electronic structure and magnetic properties of bulk and nanosized MnCo 2 O 4 diluted with Zn. The cationic distribution for tetrahedral A-site dilution is ( Co 1 − y A 2 + Zn y A 2 +) A [ Mn 3 + Co 3 + ] B O 4 ± δ , whereas B-site dilution results in ( Co 2 +) A [ Mn 1 − x B 3 + Zn x B 2 + Co 3 + ] B O 4 − δ . The strength of exchange interaction J i j between the magnetic ions in a bulk spinel lattice decreases by ∼ 15 % for A-site dilution relative to the undiluted compound; however, B-site dilution results in an enhancement in J i j by 17%. The frequency and temperature dependence of dynamic-susceptibility [ χ ac (f , T) ] studies of nanostructured compounds reveals the existence of spin-glass like behavior below the freezing temperature T F ∼ 125.7 K (for x B = 0.2) and 154.3 K (y A = 0.1). Relaxation time τ follows the Power-Law variation with a dynamical critical exponent z ν = 6.17 and microscopic spin relaxation time τ o = 4.4 × 10 − 15 s for x B = 0.2 (for y A = 0.1 , z ν = 5.2 and τ o = 5.4 × 10 − 13 s). The amplitude and peak position in χ ac (T) decreases with an increase in the DC bias field, which indicates that the spin-glass phase can survive in the presence of low fields forming a critical line with an exponent 2/3. This behavior is similar to the de Almeida-Thouless (AT-line) analysis in the T-H phase diagram which supports the existence of spin-glass like behavior below T F in these Zn diluted spinels. [ABSTRACT FROM AUTHOR]

Background: The current investigation entails the characterization of seven degradation products (DPs) formed in different stress conditions of gilteritinib employing liquid chromatography-tandem mass spectrometry (LC-MS/MS). Methodology: This study developed a stability-indicating reversed-phase high-performance liquid chromatographic (HPLC) method for precisely determining gilteritinib in the presence of its process-related impurities in bulk drug and formulation samples. To explore the stability profile of gilteritinib, it was exposed to forced degradation experiments conducted under various conditions, including acidic, basic, oxidative, photolytic, and thermal stress. These experiments revealed the degradation of gilteritinib under basic, acidic, and photolytic conditions, forming seven distinct DPs. Result: The chromatographic resolution of gilteritinib and its impurities along with DPs was effectively achieved using a Waters Symmetry C18 (250 mm × 4.6 mm, 5 μm) column using equal volumes of solvent A and B (pH 4.5 phosphate buffer and acetonitrile in 25:75 (v/v) as solvent A, acetonitrile and methanol in 75: 25 (v/v) as solvent B) pumped isocratically at 0.7 mL/min and 230 nm wavelength. The method produces an accurate fit calibration curve in 25-175 μg/mL for gilteritinib and LOQ (0.025 μg/mL) – 0.175 μg/mL for its impurities with acceptable precision, accuracy, and recovery. Conclusion: The efficacy of this method was validated through LC-MS/MS, which allowed for the verification of the chemical structures of newly generated degradation products of gilteritinib. Hence, this method is appropriate for the resolution and evaluation of process-related impurities of gilteritinib and can also be applied for evaluating stress degradation products.

We report a detailed magnetization study of the coherently strained trilayer heterostructures of metallic ferromagnet SrRuO3 (SRO)/paramagnetic-LaNiO3/SRO grown on a (001) oriented SrTiO3 single crystal substrate using the pulsed laser deposition technique. A tunable positive exchange bias (µoHEB~0.2 T, at 10 K) across the interface has been observed. Upon varying the SRO layer thickness (2 nm≤tSRO≤18 nm), the saturation magnetization (MS~0.46 µB/Ru) increases significantly owing to electronic-reconstruction across the interfaces and finite size effects. The magnitude of µoHEB increases continuously with increasing tSRO and saturates above 16 nm; however, the loop-asymmetry increases rapidly as the temperature is lowered below the ferromagnetic Curie temperature (TC) of SRO. Notable reductions in both TC (125.6K≤TC≤146.4 K) and blocking temperature TB=T* (90.6K≤T*≤ 119.2 K) are observed due to surface effects that comply with the finite-size scaling law: TC(tSRO)=TC (∞) [1-(ξo/tSRO)λ] with critical exponent λ=1.120±0.037 and correlation length ξ0=0.596±0.02 nm signifying the fact that the investigated system is an intermediate between the 3D Ising configuration and those associated with mean field approximations. [ABSTRACT FROM AUTHOR]

We report the role of Al substitution in the magnetic properties of spinel CoCr2O4 by means of temperature dependent dc and ac magnetization and heat capacity measurements. Various compositions (0.0⩽x⩾1.0) of polycrystalline Co(Cr1-xAlx)2O4 samples have been prepared by sol-gel processing and their crystal structure was investigated by X-ray diffraction which was found to crystallize in the normal cubic spinel structure. For x⩽0.1, the system exhibits multiple magnetic orderings (long range ferrimagnetic ordering TC, spin-spiral ordering TS and lock-in transition TL), similar to that of the parent compound, CoCr2O4. However, all the compositions between x=0.1 and 0.5 exhibit long range ferrimagnetic ordering below TC and also a short range order at low temperature. Spin-glass like ordering was noticed between x=0.6 and 0.8 due to the diluted Bsite occupancy, whereas the end compound CoAl2O4 (x=1.0) shows antiferromagnetic behavior. On the basis of these results, we propose a magnetic phase diagram for the Co(Cr1-xAlx)2O4 series as a function of the Al content (x) and measuring temperature (T). [ABSTRACT FROM AUTHOR]

Finite-size (d=5.4-112 nm) and surface effects on the structural, optical, and magnetic properties of ferrimagnetic inverse-spinel MnCo2O4 are reported. For d ≥ 87 nm, partial tetragonal distortion of the inverse spinel-lattice was observed. The Curie temperature TC of MnCo2O4 nanostructures, as determined by dc-magnetic susceptibility (χ) measurements, follows a finite-size scaling relation TC(d)=TC(1)[1-(ζ0/d)λ] with a shift exponent λ=0.75±0.15 and microscopic correlation length ζ0=1.4±0.3 nm, which is consistent with the mean field theory. For T>TC, χ(T) fits Néel's expression for the two-sublattice model with antiferromagnetic molecular field (exchange) constants NBB~85.16 (JBB~2.94×10-22 J), NAB~110.96 (JAB~1.91×10-22 J), and NAA~43.8 (JAA~1.13×10-22 J) and asymptotic Curie temperature Ta~717.63 K. The optical energy bandgap Eg, evaluated from the Kubelka-Munk function ([F(R∞)hω]2 =C2(hω - Eg)) is blueshifted to 2.4 eV (d~5.4 nm) from 1.73 eV (d~112 nm) due to the quantum confinement and nonstoichiometry. The role of tetragonal distortion and grain-size-effects in the intensity of crystal field transitions and variation in the magnetic ordering are further discussed and compared with Co3O4 nanostructures. [ABSTRACT FROM AUTHOR]