In-situ electrochemical impedance analysis of a commercial SOFC stack fueled by real wood gas.

The combination of solid oxide fuel cells (SOFCs) and wood gasification has the potential to significantly increase renewable electricity production and decrease emissions. Depending on the quality of the wood gas, degradation processes have a significant impact on the reliability and lifetime of the SOFC. Using electrochemical impedance spectroscopy (EIS) and subsequent distribution of relaxation times (DRT) analysis, the impact on the degradation of coupling wood gasification with a commercial SOFC stack is determined in this study. The thermal behavior of the SOFC stack under various operating conditions, as well as various synthetic wood gas mixtures classified by their hydrogen-to-carbon (H/C) ratio, was assessed. The decrease in the H/C ratio from 8 to 1, observed during syngas and real wood gas operation, leads to a rightward shift in the Nyquist plots, suggesting an increase in the SOFC stack's impedance. Correlations between variations in the H/C ratio and their effects on anodic electrooxidation, ionic conduction, gas transport, and diffusion were identified using DRT analysis to interpret the EIS results. By incorporating an upstream desulfurization system and ensuring an H/C ratio greater than 2, the coupling of biomass gasification with the SOFC stack was stable to degradation issues.

Measurement of T1ρ dispersion with compressed sensing and magnetization prepared radial balanced steady-state free precession in spontaneous human osteoarthritis.

PURPOSE: To assess the potential for accelerating continuous-wave (CW) T1ρ dispersion measurement with compressed sensing approach via studying the effect that the data reduction has on the ability to detect differences between intact and degenerated articular cartilage with different spin-lock amplitudes and to assess quantitative bias due to acceleration. METHODS: Osteochondral plugs (n = 27, 4 mm diameter) from femur (n = 14) and tibia (n = 13) regions from human cadaver knee joints were obtained from commercial biobank (Science Care, USA) under Ethical permission 134/2015. MRI of specimens was performed at 9.4T with magnetization prepared radial balanced SSFP (bSSFP) readout sequence, and the CWT1ρ relaxation time maps were computed from the measured data. The relaxation time maps were evaluated in the cartilage zones for different acceleration factors. For reference, Osteoarthritis Research Society International (OARSI) grading and biomechanical measurements were performed and correlated with the MRI findings. RESULTS: Four-fold acceleration of CWT1ρ dispersion measurement by compressed sensing approach was feasible without meaningful loss in the sensitivity to osteoarthritic (OA) changes within the articular cartilage. Differences were significant between intact and OA groups in the superficial and transitional zones, and CWT1ρ correlated moderately with the reference measurements (0.3 < r < 0.7). CONCLUSION: CWT1ρ was able to differentiate between intact and OA cartilage even with four-fold acceleration. This indicates that acceleration of CWT1ρ dispersion measurement by compressed sensing approach is feasible with negligible loss in the sensitivity to osteoarthritic changes in articular cartilage.

The acute effects of nonsleep deep rest on perceptual responses, physical, and cognitive performance in physically active participants.

This study aimed to examine the effect of nonsleep deep rest (NSDR) on physical and cognitive performance, as well as sleepiness, acute readiness, recovery, stress, and mood state in physically active participants. A total of 65 physically active participants (42 male, 23 female) were randomly assigned into two groups: an experimental group (NSDR, n = 34), in which participants completed a 10-min NSDR intervention, and a control group (CON, n = 31), whereby participants sat passively for 10 min. Testing measures were assessed immediately pre and 10 min post each condition and comprised completing a hand grip strength dynamometer test and a countermovement jump test on force plates, cognitive function measures via a psychomotor vigilance task (PVT-B), and a Simon task test, along with four questionnaires to assess sleep, recovery, and mood state. A significant Group × Time interaction favored the NSDR condition for handgrip strength, median reaction time during the PVT-B, and accuracy percentage during the Simon task. Questionnaire responses demonstrated NSDR to be associated with significant benefits to physical readiness, emotional balance, overall recovery, negative emotional state, overall stress, and tension in comparison to CON (p < .05). The NSDR intervention could be a valuable strategy for acutely enhancing overall well-being and readiness.

Water rotational relaxation time measurement by shortwave infrared micro spectroscopy(SWIR) at sub-zero temperatures.

The shortwave infrared spectroscopy (SWIR) is the noble method which allows to evaluate the rotational relaxation time of water (RRTW) in a sample. Because SWIR requires the reference sample of pure water, the measurement temperature is limited only at above 0 °C. In this study, we expanded this temperature limitation of SWIR by using alternative reference solutions with freezing points below 0 °C, including sugar and glycerol solutions. The results showed that some reference sample solutions are useable for evaluating RRTW in samples below 0 °C. It was found that RRTW in solution measured by newly proposed SWIR agrees with RRTW measured by dielectric spectroscopy in 10% accuracy when it is shorter than 100psec.

Tailoring component incorporation for homogenized perovskite solar cells.

Deep-level traps at the buried interface of perovskite and energy mismatch problems between the perovskite layer and heterogeneous interfaces restrict the development of ideal homogenized films and efficient perovskite solar cells (PSCs) using the one-step spin-coating method. Here, we strategically employed sparingly soluble germanium iodide as a homogenized bulk in-situ reconstruction inducing material preferentially aggregated at the perovskite buried interface with gradient doping, markedly reducing deep-level traps and withstanding local lattice strain, while minimizing non-radiative recombination losses and enhancing the charge carrier lifetime over 9 µs. Furthermore, this gradient doping assisted in modifying the band diagram at the buried interface into a desirable flattened alignment, substantially mitigating the energy loss of charge carriers within perovskite films and improving the carrier extraction equilibrium. As a result, the optimized device achieved a champion power conversion efficiency of 25.24% with a fill factor of up to 84.65%, and the unencapsulated device also demonstrated excellent light stability and humidity stability. This work provides a straightforward and reliable homogenization strategy of perovskite components for obtaining efficient and stable PSCs.

[Airway management in neonates and infants : Recommendations according to the ESAIC/BJA guidelines]. / Atemwegssicherung bei Neugeborenen und Säuglingen : Handlungsempfehlung gemäß der BJA/ESAIC-Leitlinie.

Securing an airway enables the oxygenation and ventilation of the lungs and is a potentially life-saving medical procedure. Adverse and critical events are common during airway management, particularly in neonates and infants. The multifactorial reasons for this include patient-dependent, user-dependent and also external factors. The recently published joint ESAIC/BJA international guidelines on airway management in neonates and infants are summarized with a focus on the clinical application. The original publication of the guidelines focussed on naming formal recommendations based on systematically documented evidence, whereas this summary focusses particularly on the practicability of their implementation.

The recruitment of mechanosensitive enteric neurons in the guinea pig gastric fundus is dependent on ganglionic stretch level.

BACKGROUND: Serving as a reservoir, the gastric fundus can expand significantly, with an initial receptive and a following adaptive relaxation, controlled by extrinsic and intrinsic reflex circuits, respectively. We hypothesize that mechanosensitive enteric neurons (MEN) are involved in the adaptive relaxation, which is initiated when a particular gastric volume and a certain stretch of the stomach wall is reached. To investigate whether the responsiveness of MEN in the gastric fundus is dependent on tissue stretch, we performed mechanical stimulations in stretched versus ganglia "at rest". METHODS: Responses of myenteric neurons in the guinea pig gastric fundus were recorded with membrane potential imaging using Di-8-ANEPPS. MEN were identified by small-volume intraganglionic injection in ganglia stretched to different degrees using a self-constructed stretching tool. Immunohistochemical staining identified the neurochemical phenotype of MEN. Hexamethonium and capsaicin were added to test their effect on recruited MEN. KEY RESULTS: In stretched compared to "at rest" ganglia, significantly more MEN were activated. The change in the ganglionic area correlated significantly with the number of additional recruited MEN. The additional recruitment of MEN was independent from nicotinic transmission and the ratio of active MEN in stretched ganglia shifted towards a nitrergic phenotype. CONCLUSION AND INFERENCES: The higher number of active MEN with increasing stretch of the ganglia and their greater share of nitrergic phenotype might indicate their contribution to the adaptive relaxation. Further experiments are necessary to address the receptors involved in mechanotransduction.

Prevalence and 20-year trends in meditation, yoga, guided imagery and progressive relaxation use among US adults from 2002 to 2022.

Meditation, yoga, guided imagery, and progressive relaxation are promoted as complementary approaches for health and wellbeing in the United States, but their uptake by different sociodemographic groups is unclear. This study assessed the prevalence and 20 year trends in the use of these practices in US adults between 2002-2022. We examined practice use and associations with sociodemographic and health factors in a population-weighted analysis of n = 134,959 participants across 5 cycles of the National Health Interview Survey. The overall use of meditation (18.3%, 60.53 million), yoga (16.8%, 55.78 million) and guided imagery/progressive relaxation (6.7%, 22.22 million) increased significantly from 2002 to 2022. Growth was consistent across most sociodemographic and health strata, however users of 'Other' race (comprising 54% Indigenous Americans, Odds Ratios; ORs = 1.28-1.70) and users with moderate (ORs = 1.19-1.29) psychological distress were overrepresented across all practices, and those with severe psychological distress were overrepresented in meditation (OR = 1.33) and guided imagery/progressive relaxation (OR = 1.42). Meditation use has accelerated over time for 65 + year olds (OR = 4.22), people not accessing mental health care (OR = 1.39), and less educated (OR = 4.02) groups, potentially reflecting unmet health needs. Health professionals should consider the extensive use of complementary practices in service and treatment planning and consider their risks and benefits.

Sodium MRI of the Lumbar Intervertebral Discs of the Human Spine: An Ex Vivo Study.

BACKGROUND: Lower back pain affects 75%-85% of people at some point in their lives. The detection of biochemical changes with sodium (23Na) MRI has potential to enable an earlier and more accurate diagnosis. PURPOSE: To measure 23Na relaxation times and apparent tissue sodium concentration (aTSC) in ex-vivo intervertebral discs (IVDs), and to investigate the relationship between aTSC and histological Thompson grade. STUDY TYPE: Ex-vivo. SPECIMEN: Thirty IVDs from the lumbar spines of 11 human body donors (4 female, 7 male, mean age 86 ± 8 years). FIELD STRENGTH/SEQUENCE: 3 T; density-adapted 3D radial sequence (DA-3D-RAD). ASSESSMENT: IVD 23Na longitudinal (T1), short and long transverse (T2s* and T2l*) relaxation times and the proportion of the short transverse relaxation (ps) were calculated for one IVD per spine sample (11 IVDs). Furthermore, aTSCs were calculated for all IVDs. The degradation of the IVDs was assessed via histological Thompson grading. STATISTICAL TESTS: A Kendall Tau correlation (τ) test was performed between the aTSCs and the Thompson grades. The significance level was set to P < 0.05. RESULTS: Mean 23Na relaxation parameters of a subset of 11 IVDs were T1 = 9.8 ± 1.3 msec, T2s* = 0.7 ± 0.1 msec, T2l* = 7.3 ± 1.1 msec, and ps = 32.7 ± 4.0%. A total of 30 IVDs were examined, of which 3 had Thompson grade 1, 4 had grade 2, 5 had grade 3, 5 had grade 4, and 13 had grade 5. The aTSC decreased with increasing degradation, being 274.6 ± 18.9 mM for Thompson grade 1 and 190.5 ± 29.5 mM for Thompson grade 5. The correlation between whole IVD aTSC and Thompson grade was significant and strongly negative (τ = -0.56). DATA CONCLUSION: This study showed a significant correlation between aTSC and degenerative IVD changes. Consequently, aTSC has potential to be useful as an indicator of degenerative spinal changes. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 1.

Formation of a Decanuclear Organometallic Dysprosium Complex via a Radical-Radical Cross-Coupling Reaction.

Over the years, polynuclear cyclic or torus complexes have attracted increasing interest due to their unique metal topologies and properties. However, the isolation of polynuclear cyclic organometallic complexes is extremely challenging due to their inherent reactivity, which stems from the labile and reactive metal-carbon bonds. In this study, the pyrazine ligand undergoes a radical-radical cross-coupling reaction leading to the formation of a decanuclear [(Cp*)20Dy10(L1)10]·12(C7H8) (1; where L1 = anion of 2-prop-2-enyl-2H-pyrazine) complex, where all DyIII metal centers are bridged by the anionic L1 ligand. Amongst the family of polynuclear Ln organometallic complexes bearing CpR2Lnx units, 1 features the highest nuclearity obtained to date. In-depth computational studies were conducted to elucidate the proposed reaction mechanism and formation of L1, while probing of the magnetic properties of 1, revealed slow magnetic relaxation upon application of a static dc field.

Magnetic Structure-Dependent Ultrafast Spin Relaxation in Magnet CrI3: A Time-Domain ab Initio Study.

Two-dimensional magnet CrI3 is a promising candidate for spintronic devices. Using nonadiabatic molecular dynamics and noncollinear spin time-dependent density functional theory, we investigated hole spin relaxation in two-dimensional CrI3 and its dependence on magnetic configurations, impacted by spin-orbit and electron-phonon interactions. Driven by in-plane and out-of-plane iodine motions, the relaxation rates vary, extending from over half a picosecond in ferromagnetic systems to tens of femtoseconds in certain antiferromagnetic states due to significant spin fluctuations, associated with the nonadiabatic spin-flip in tuning to the adiabatic flip. Antiferromagnetic CrI3 with staggered layer magnetic order notably accelerates adiabatic spin-flip due to enhanced state degeneracy and additional phonon modes. Ferrimagnetic CrI3 shows a transitional behavior between ferromagnetic and antiferromagnetic types as the magnetic moment changes. These insights into the spin dynamics of CrI3 underscore its potential for rapid-response spintronic applications and advance our understanding of two-dimensional materials for spintronics.

Sodium tanshinone IIA sulfonate protects vascular relaxation in ApoE-knockout mice by inhibiting the SYK-NLRP3 inflammasome-MMP2/9 pathway.

BACKGROUND: Hyperlipidemia damages vascular wall and serves as a foundation for diseases such as atherosclerosis, hypertension and stiffness. The NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome is implicated in vascular dysfunction associated with hyperlipidemia-induced vascular injury. Sodium tanshinone IIA sulfonate (STS), a well-established cardiovascular protective drug with recognized anti-inflammatory, antioxidant, and vasodilatory properties, is yet to be thoroughly investigated for its impact on vascular relaxant imbalance induced by hyperlipidemia. METHODS: In this study, we treated ApoE-knockout (ApoE-/-) mouse with STS and assessed the activation of the NLRP3 inflammasome, expression of MMP2/9, integrity of elastic fibers, and vascular constriction and relaxation. RESULTS: Our findings reveal that STS intervention effectively preserves elastic fibers, significantly restores aortic relaxation function in ApoE-/- mice, and reduces their excessive constriction. Furthermore, STS inhibits the phosphorylation of spleen tyrosine kinase (SYK), suppresses NLRP3 inflammasome activation, and reduces MMP2/9 expression. CONCLUSIONS: These results demonstrate that STS protects vascular relaxation against hyperlipidemia-induced damage through modulation of the SYK-NLRP3 inflammasome-MMP2/9 pathway. This research provides novel insights into the mechanisms underlying vascular relaxation impairment in a hyperlipidemic environment and uncovers a unique mechanism by which STS preserves vascular relaxation, offering valuable foundational research evidence for its clinical application in promoting vascular health.

Rapid simultaneous estimation of relaxation rates using multi-echo, multi-contrast MRI.

PURPOSE: Multi-echo, multi-contrast methods are increasingly used in dynamic imaging studies to simultaneously quantify R2∗ and R2. To overcome the computational challenges associated with nonlinear least squares (NLSQ) fitting, we propose a generalized linear least squares (LLSQ) solution to rapidly fit R2∗ and R2. METHODS: Spin- and gradient-echo (SAGE) data were simulated across T2∗ and T2 values at high (200) and low (20) SNR. Full (four-parameter) and reduced (three-parameter) parameter fits were implemented and compared with both LLSQ and NLSQ fitting. Fit data were compared to ground truth using concordance correlation coefficient (CCC) and coefficient of variation (CV). In vivo SAGE perfusion data were acquired in 20 subjects with relapsing-remitting multiple sclerosis. LLSQ R2∗ and R2, as well as cerebral blood volume (CBV), were compared with the standard NLSQ approach. RESULTS: Across all fitting methods, T2∗ was well-fit at high (CCC = 1, CV = 0) and low (CCC ≥ 0.87, CV ≤ 0.08) SNR. Except for short T2∗ values (5-15 ms), T2 was well-fit at high (CCC = 1, CV = 0) and low (CCC ≥ 0.99, CV ≤ 0.03) SNR. In vivo, LLSQ R2∗ and R2 estimates were similar to NLSQ, and there were no differences in R2∗ across fitting methods at high SNR. However, there were some differences at low SNR and for R2 at high and low SNR. In vivo NLSQ and LLSQ three parameter fits performed similarly, as did NLSQ and LLSQ four-parameter fits. LLSQ CBV nearly matched the standard NLSQ method for R2∗- (0.97 ratio) and R2-CBV (0.98 ratio). Voxel-wise whole-brain fitting was faster for LLSQ (3-4 min) than NLSQ (16-18 h). CONCLUSIONS: LLSQ reliably fit for R2∗ and R2 in simulated and in vivo data. Use of LLSQ methods reduced the computational demand, enabling rapid estimation of R2∗ and R2.

Relaxation intervention to improve diabetic foot ulcer healing: protocol for a pilot study with a nested qualitative study.

OBJECTIVE: A mixed-methods approach nested in a pilot three-arm randomised controlled trial (RCT) was conducted to evaluate the feasibility and acceptability of an intervention of progressive muscle relaxation with guided imagery (experimental group) compared to a neutral guided imagery placebo (active control group) and a group that did not receive any psychological intervention (passive control group). The purpose was to inform a future definitive RCT that will test its effectiveness. Qualitatively, this study examined patients and health professionals' perspectives regarding the relaxation intervention, in order to assess the acceptability and applicability of relaxation as an adjuvant therapy. METHOD: Participants must have had a diagnosis of diabetes and diabetic foot disease; one or two active hard-to-heal ulcers at the time of the assessment; and clinical levels of stress or anxiety or depression. Participants were randomised and assessed at three timepoints after the first hospital consultation for hard-to-heal diabetic foot ulcer (DFU). RESULTS: Rates of eligibility, recruitment, refusal, adherence to study protocol, participation in follow-up and dropout, and patients' satisfaction with the relaxation intervention were assessed as primary outcomes. Secondary outcomes were DFU healing; patients' DFU-related quality of life; physical and mental quality of life; perceived stress; emotional distress; adherence to DFU care; perceptions of DFU; as well as arterial systolic/diastolic pressure and heart rate. CONCLUSION: The results of this pilot study contributed to clarification and better elucidation of the benefits of relaxation techniques regarding patients' HRQoL and DFU healing. DECLARATION OF INTEREST: Funding: This study was conducted at the Psychology Research Centre (CIPsi/UM) School of Psychology, University of Minho, Portugal and supported by the Foundation for Science and Technology (FCT) through the Portuguese State Budget (UIDB/01662/2020) and by a PhD fellowship from FCT assigned to GF (SFRH/BD/131780/2017) and an FCT grant (PTDC/PSI-GER/28163/2017) assigned to MGP. The authors have no conflicts of interest to declare.

1H, 13C and 15N assignment of self-complemented MrkA protein antigen from Klebsiella pneumoniae.

Klebsiella pneumoniae (Kp) poses an escalating threat to public health, particularly given its association with nosocomial infections and its emergence as a leading cause of neonatal sepsis, particularly in low- and middle-income countries (LMICs). Host cell adherence and biofilm formation of Kp is mediated by type 1 and type 3 fimbriae whose major fimbrial subunits are encoded by the fimA and mrkA genes, respectively. In this study, we focus on MrkA subunit, which is a 20 KDa protein whose 3D molecular structure remains elusive. We applied solution NMR to characterize a recombinant version of MrkA in which the donor strand segment situated at the protein's N-terminus is relocated to the C-terminus, preceded by a hexaglycine linker. This construct yields a self-complemented variant of MrkA. Remarkably, the self-complemented MrkA monomer loses its capacity to interact with other monomers and to extend into fimbriae structures. Here, we report the nearly complete assignment of the 13C,15N labelled self-complemented MrkA monomer. Furthermore, an examination of its internal mobility unveiled that relaxation parameters are predominantly uniform across the polypeptide sequence, except for the glycine-rich region within loop 176-181. These data pave the way to a comprehensive structural elucidation of the MrkA monomer and to structurally map the molecular interaction regions between MrkA and antigen-induced antibodies.

Clinical validation of fully automated laminar knee cartilage transverse relaxation time (T2) analysis in anterior cruciate ligament (ACL)-injured knees- on behalf of the osteoarthritis (OA)-Bio consortium.

Background: Magnetic resonance imaging (MRI) cartilage transverse relaxation time (T2) reflects cartilage composition, mechanical properties, and early osteoarthritis (OA). T2 analysis requires cartilage segmentation. In this study, we clinically validate fully automated T2 analysis at 1.5 Tesla (T) in anterior cruciate ligament (ACL)-injured and healthy knees. Methods: We studied 71 participants: 20 ACL-injured patients with, and 22 without dynamic knee instability, 13 with surgical reconstruction, and 16 healthy controls. Sagittal multi-echo-spin-echo (MESE) MRIs were acquired at baseline and 1-year follow-up. Femorotibial cartilage was segmented manually; a convolutional neural network (CNN) algorithm was trained on MRI data from the same scanner. Results: Dice similarity coefficients (DSCs) of automated versus manual segmentation in the 71 participants were 0.83 (femora) and 0.89 (tibiae). Deep femorotibial T2 was similar between automated (45.7±2.6 ms) and manual (45.7±2.7 ms) segmentation (P=0.828), whereas superficial layer T2 was slightly overestimated by automated analysis (53.2±2.2 vs. 52.1±2.1 ms for manual; P<0.001). T2 correlations were r=0.91-0.99 for deep and r=0.86-0.97 for superficial layers across regions. The only statistically significant T2 increase over 1 year was observed in the deep layer of the lateral femur [standardized response mean (SRM) =0.58 for automated vs. 0.52 for manual analysis; P<0.001]. There was no relevant difference in baseline/longitudinal T2 values/changes between the ACL-injured groups and healthy participants, with either segmentation method. Conclusions: This clinical validation study suggests that automated cartilage T2 analysis from MESE at 1.5T is technically feasible and accurate. More efficient 3D sequences and longer observation intervals may be required to detect the impact of ACL injury induced joint instability on cartilage composition (T2).

Vibrational spectroscopy of dynamic interactions and relaxation processes in ionic systems.

In recent years, there has been a boom in the publication of research results on ionic (electrolyte) systems used in the creation of electrochemical energy systems (batteries, supercapacitors, etc.). One of the alternative ways to obtain dynamic information in ionic systems is spectroscopic experiments, and the most valuable information on the behavior of condensed systems at picosecond and adjacent time intervals is provided by vibrational spectroscopy. The source of this information is the analysis of the shape and width of the lines in the vibrational spectra of ion systems. This review aims to systematize the theoretical and methodological aspects of the study of the dynamics of ion systems by vibrational spectroscopy.

Control of Anisotropy and Magnetic Hyperthermia Effect by Addition of Cobalt on Magnetite Nanoparticles.

Magnetic hyperthermia (MH) has emerged as a promising technology with diverse applications in medical and technological fields, leveraging the remote induction of temperature elevation through an alternating magnetic field. While Fe3O4 nanoparticles with an average size around 12-25 nm are commonly employed in MH systems, this study introduces a strategy to produce smaller particles (less than or equal to 10 nm) with enhanced heating efficiency, as measured by specific power absorption (SPA). We conducted an exhaustive and detailed investigation into the morphological and magnetic properties of CoxFe3-xO4 nanoparticles, aiming to optimize their MH response. By varying the Co content, we successfully tuned the effective magnetic anisotropy while maintaining saturation magnetization nearly constant. The MH analysis indicates that these nanoparticles predominantly heat through the Néel mechanism, demonstrating robust reproducibility across different concentrations, viscosity mediums, and ac field conditions. Notably, we identified an optimal anisotropy or Co concentration that maximizes SPA, crucial for developing magnetic systems requiring particles with specific sizes. This work contributes to advancing the understanding and application of MH, particularly in tailoring nanoparticle properties for targeted and efficient heat generation in various contexts.

Methods to Quantitatively Measure Topological Changes Induced by DNA-Binding Proteins In Vivo and In Vitro.

Agarose gel electrophoresis in the presence of chloroquine (an intercalating agent) can be used to resolve and characterize the population of topoisomers present in supercoiled plasmid DNA. Here, we describe how chloroquine gel electrophoresis can capture changes in the topoisomer distribution of plasmid DNA that bears a recognition site for a given protein, if that plasmid is isolated from cells producing the protein of interest. We also describe two complementary in vitro assays, which can be used to capture transient changes in DNA supercoiling caused when the purified protein of interest engages its recognition site. These are the topoisomerase I-mediated relaxation assay (TMRA) and the ligase-mediated supercoiling assay (LMSA). Together, these in vivo and in vitro methods allow the capture and measurement of changes in DNA topology that are triggered by DNA-binding proteins, especially those that multimerize on or spread along DNA.

Viscosity of Al-Ni-Co-Nd(Sm) glass-forming melts at high temperatures.

Obtaining amorphous alloys with good mechanical and anticorrosion properties is an important problem of modern condensed matter physics. Since the preparation of amorphous alloys involves casting them from liquid state, information on the properties of the melts is needed. Viscosity is one of the most informative structure-sensitive property of melts. In this paper viscosity of some glass-forming Al-Ni-Co-Nd(Sm) melts with different ratio of transition metals was studied using damped oscillation method in a wide temperature range up to 1550 K. Activation energies of the viscous flow were calculated from the experimental data. The hysteresis of viscosity temperature dependences during heating and subsequent cooling was found. It can be associated with a melt transition to a more homogeneous state. The repeated heating and cooling of the melts without crystallization lead to Arrhenius type of viscosity temperature dependences.