Different Trends Of Changes Research Articles

Changes in the Centers of Rotation in Different Prosthetic Segments Following Continuous Two-Level Cervical Disc Replacement: A Retrospective Study

To observe the short-term to medium-term therapeutic effects and radiological outcomes of adjacent 2-level cervical spondylosis treated with artificial cervical disc replacement (ACDR) using Mobi-C and Bryan discs. To observe changes and discrepancies in the flexion-extension centers of rotation (FE-COR) of different ACDR segments. Twenty-four patients undergoing 2-level (C4/5 and C5/6) ACDR were analyzed retrospectively (11 patients in the Mobi-C group and 13 patients in the Bryan group). Clinical outcomes were assessed using modified Japanese Orthopedic Association score, Neck Disability Index, and visual analog scale. Preoperative and 2years' follow-up radiographs were collected to compare total cervical spine curvature (C2-C7) range of motion (ROM), upper and lower ACDR segmental ROM, and the operated adjacent segmental ROM. The FE-COR of the ACDR segment was measured using the mid-plumb line method. The degree of disc degeneration in the adjacent segment was observed. At the 2years' follow-up, in both group, the modified Japanese Orthopedic Association score increased significantly, and the Neck Disability Index and neck and upper extremity visual analog scale scores decreased significantly compared with preoperative (P<0.05). There were no significant statistical differences in postoperative scores between the 2 groups (P > 0.05). The overall cervical ROM, the upper and lower segmental ROM at the 2years' follow-up showed no significant statistical differences compared with the preoperative period (P > 0.05). There was no statistically significant difference in the adjacent segmental ROMs compared with the preoperative period (P > 0.05). Furthermore, the statistical analysis revealed no significant differences in the measurements of the ROM at each time points between the Mobi-C Group and the Bryan Group (P > 0.05). There was no significant difference in the preoperative FE-COR-X (indicating the horizontal position of the point in the coordinate system) and FE-COR-Y (indicating the vertical position of the point in the coordinate system) of upper or lower ACDR segments between the 2 groups (P > 0.05). At the 2years' follow-up, there were significant differences both in FE-COR-X and FE-COR-Y between the 2 groups (P < 0.05). For the Mobi-C group, in both the upper and lower segment, the FE-COR-X significantly increased compared with preoperative (P < 0.05), while the FE-COR-Y decreased compared with preoperative (P < 0.05). For the Bryan group, no significant changes were observed in the upper or lower segment in both FE-COR-X and FE-COR-Y compared with preoperative (P > 0.05). Fourty-eight adjacent segments (24 superior and 24 inferior segments) were included in the studies of adjacent segment disease. Four segments showed imaging adjacent segment disease (4/48, 8.33%) in 4 patients, of which 2 were mild and 2 were moderate according to the grading criteria. Among them, 2 were from the Mobi-C group and 2 were from the Bryan group. No severe imaging degeneration was observed. In continuous 2-level cervical ACDR surgery, both Mobi-C and Bryan artificial cervical discs achieved satisfactory clinical outcomes in the short to medium term postoperatively. The FE-COR exhibited different trends of change. In the Mobi-C group, the FE-COR for both upper and lower segments shifted anteriorly and inferiorly, whereas in the Bryan group, whether upper or lower, the FE-COR remained closer to the preoperative state. The changes in FE-COR did not significantly affect the short-term to medium-term clinical outcomes postoperatively.

An evaluation concentrated on post-peak carbon trend scenarios designing and carbon neutral pathways in Hebei Province, China

China has committed to peak carbon emissions by 2030 and become carbon neutral by 2060. Hebei, as a major energy province in China, has more challenging carbon peaking and carbon neutrality targets. Based on the extended STIRPAT model, this paper evaluates the time to peak carbon and post-peak carbon trend changes in Hebei province under different scenarios from 2020 to 2060. Based on the support vector machine model with particle swarm optimization, this paper evaluates the carbon neutral pathways under different scenarios in Hebei province from 2020 to 2060 in terms of forests, croplands, wetlands, grasslands and Carbon Capture, Utilization and Storage (CCUS). The results show that a monotonically flat trend without inflection point, a single-inflection-point plateau-period trend and a multi-inflection-point inverted U-wave trend occur after carbon peaks. Hebei Province can achieve carbon neutrality by 2060 under the policy scenario and the enhanced scenario, and the enhanced scenario is better. Comparing with existing studies, the innovation of this paper is to design different trends of changes after carbon peak, combining carbon absorption and carbon emission, and providing more diversified development paths for carbon neutral strategies through a more integrated perspective and multi-scenario comprehensive analysis. Therefore, In the future, Hebei Province should establish a platform for carbon emissions monitoring and carbon footprint assessment, and set up an early warning and assessment mechanism for carbon peaking, so as to prevent a rebound trend in carbon emissions after peaking. At the same time, it should introduce and develop carbon capture and conversion technologies and promote the low-carbon transformation of the industrial and energy sectors, thereby forcing the early realization of peak carbon. Pay attention to the role of forestry resources in carbon neutrality, increase carbon sink resources such as forests and wetlands, promote the development of CCUS, and enhance the implementation of the policy.

Spatial–Temporal Evolution and Influential Factors of Eco-Efficiency in Chinese Urban Agglomerations

Against the background of a high-quality development philosophy, the realization of the coordinated development of the economy, environment, and resources is particularly important. This study adopts the super-efficiency slacks-based measure (SBM) model to evaluate the eco-efficiency of 208 cities in 19 urban agglomerations in China from 2006 to 2020, and the kernel density estimation and spatial econometric specifications are combined to reveal the spatial–temporal evolution. Finally, Tobit regression is used to analyze the driving factors of the eco-efficiency of urban agglomerations in China. The main results can be summarized as follows: (1) The eco-efficiency of Chinese urban agglomerations is generally low, and the differences in eco-efficiency between urban agglomerations are obvious, with different trends of change. (2) In terms of the time series, the sample period shows a “steadily rising” trend followed by a “fluctuating downward” trend. From the results of the kernel density estimation, the internal difference in the overall eco-efficiency of urban agglomerations shows the trend of a small decline followed by a gradual increase. (3) From the spatial point of view, the eco-efficiency of urban agglomerations decreased from the coast to the inland areas, and there was a “cluster effect”. The overall eco-efficiency of urban agglomerations shows a trend of spatial aggregation. (4) From the perspective of influencing factors, fiscal expenditure, opening-up level, and population density have a significant negative correlation with the eco-efficiency of urban agglomerations, while science and technology investment, industrial structure, and urbanization level have a significant positive correlation with the eco-efficiency of urban agglomerations. The research in this paper provides guidance for the coordinated development of urban agglomerations and the formulation of environmental policies.

Effects of tensile deformation on the electronic and optical properties of O atom adsorbed monolayer β-Be3N2

Based on density functional theory, the effects of tensile deformation on the stability, electronic properties and optical properties of [Formula: see text]-Be3N2 adsorbed O atom system were investigated. The results show that the structure of [Formula: see text]-Be3N2 is deformed because of the O atoms’ adsorption, which pulls up the Be atoms and repels the N atoms, leading to the re-hybridization of the N atoms with the Be atomic orbitals, thus changing its bandgap. With tensile deformation, the adsorption energy of [Formula: see text]-Be3N2 adsorbed O atom system decreases with increasing tensile deformation, and the stability of the system increases. The energy bandgaps of [Formula: see text]-Be3N2 adsorbed O atom system and [Formula: see text]-Be3N2 systems exhibit different trends of change, respectively. As the stretching rate increases, the system’s maximum absorption and reflection peaks alter.

Secular changes (1826–2021) of human thermal stress according to UTCI in Kraków (southern Poland)

AbstractThe set of meteorological data from the Jagiellonian University station in Kraków is one of the longest‐recorded in central Europe. Measurement records date back to 1826. Based on the average monthly values of air temperature, total cloudiness, water vapour pressure and wind speed at 1200 UTC, the UTCI values were calculated and the occurrence of cold stress (UTCI &lt; −13°C) and heat stress (UTCI &gt; 32°C) was estimated. The variability of the applied measures of thermal stress conditions was studied both annually and in individual seasons (MAM, JJA, SON, DJF). Statistically significant changes in the studied characteristics of the bioclimate were found. Average annual UTCI values increased at the rate of 0.27°C/10 years. In individual seasons, the trend of UTCI changes ranged from 0.10°C/10 years in summer to 0.43°C/10 years in winter. The number of days with cold stress decreased by 1.8 days/10 years and the number of days with heat stress significantly increased (0.5 days/10 years). Two subperiods with different trends of changes were determined. The first covers the years 1826–1940, and the second, 1941–2021. The former indicates a negative UTCI trend of −0.17°C/10 years, and the latter, an increasing trend of 1.09°C/10 years. The last eight decades have brought a decrease in cold days of 6.5/10 years and an increase in heat days of 2.6/10 years.

Removing starch granule-associated surface lipids affects structure of heat-moisture treated hull-less barley starch

The effects of starch granule-associated surface lipids removal on hull-less barley starch structure formed by heat-moisture treatment were investigated. Removing surface lipids made the peak at 2θ of 13° disappear and resulted in higher lamellar peak intensity after harsh treatment and a lower reduction in mass fractal dimension (from 2.49 to 2.43) and radius of gyration (from 24.3 to 24.0) when temperature increased from 100 to 120 °C at 20 % moisture. Treatment at 25 % moisture and 120 °C decreased relative crystallinity (from 15.73 % to 7.43 %) and Gaussian peak area (from 646.7 to 137.7) of native starch, and decreased relative crystallinity (from 14.24 % to 12.56 %) and Gaussian peak area (from 604.1 to 539.6) for starch without surface lipids. Different trends of change in lamellar thickness, linear crystallinity, peak temperatures, and enthalpy of gelatinization were observed among modified starches with increasing temperature and/or moisture content. These results demonstrate that removing surface lipids changes structure of heat-moisture treated starch.

Ballistic Behaviour of PACVD-Modified Textiles

A comprehensive study was performed using the Plasma Assisted Chemical Vapour Deposition (PACVD) modification of ultrahigh molecular weight polyethylene (UHMWPE) fibrous composites and paramid fabrics with the deposition of fluoro-or silane-like-polymer onto their surface. Research on the resistance to fragments was performed on the basis of our own testing procedure elaborated on the basis of the STANAG 2920 Ballistic Test Method For Personal Armour Materials And Combat Clothing, revision 2. The model insert systems made of the modified or unmodified unwoven sheets of UHMWPE fibres exhibited significantly different trends of changes in fragment-proofness when the temperature together with humidity were applied as the ageing factors. In the inserts made of modified unwoven sheets, an increase in the V50 value was observed, while the V50 of the inserts made of unmodified sheets decreased along with the extension of the accelerated ageing process. Modification with low-temperature plasma in the presence of vapours of low-molecular fluorine- or silane-genic substrates altered the properties of the fabrics and unwoven sheets. PACVD modification allows to prevent the destructive influence of humidity during the aging process.

Stress profile in bulk of seeds in a shallow model silo as influenced by mobilisation of particle-particle and particle-wall friction: Experiments and DEM simulations

We present an experiment and the results of DEM simulations of the stress profile within a bulk of seeds in a shallow cylindrical model silo. The goal of our study is to understand the microscopic origins of the impact of friction mobilisation during particle-particle and particle-wall contacts on the distribution of stress in bulk of seeds. Experiments were performed with horse beans and field pea seeds. Mobilisation of friction was increased a) experimentally, by hanging a dead load on the wall of the cylindrical container holding seeds, and b) in DEM simulations, through small vertical movements of the silo wall. DEM simulations were performed with spherical particles and axially symmetric clusters of spheres containing rolling friction. It was found that the radial profile of the normal pressure σz(r) on the bottom of a shallow silo may be constant, increasing, or decreasing depending on the particle shape and filling method. Consequently, the radial profile of the shear stress τ(r) in the bulk of particles follows linear, convex, or concave relationships, respectively. Different trends of change of the radial profile of shear stress during down- and upward movement of the wall were observed. During downward movement of the wall the shear stress increased nearly uniformly along the radial position. During the upward movement a zone of change of shear stress was distinctly reduced. This effect may be a result of the participation of compressive and lack of tensional interactions in building of shear resistance.

Coping and Changes in Arousal After Exposure to +Gz Load.

Acceleration load causes several physiological changes that play important roles in pilot performance. One of the problems is determining individual factors responsible for the differences in changes in the level of central nervous system (CNS) arousal after exposure to acceleration loads. We were interested in whether the coping style and anxiety as a trait might differentiate the subjects in terms of reactions of the CNS to +Gz load-related stress. Examined were 31 male volunteers with ages between 23 and 30 yr. Measurements were obtained under controlled conditions before, during, and every 2 min up to 12 min after centrifugation. The study was conducted using the Coping Inventory for Stressful Situations (CISS) and State Trait Anxiety Inventory. The value of Critical Flicker Fusion Threshold (CFFT) corresponded to the level of CNS arousal. Two significantly different trends of changes in CNS arousal were identified: class 1 (higher level of fatigue following +Gz load) and class 2 (lower level of fatigue following +Gz load). Significant differences were observed in CISS scores with Task-Oriented Coping value in class 1 (M = 65.94, SD = 5.47) being considerably greater than in class 2 (M = 62, SD = 4.37). For Emotion-Oriented and Distraction Coping, the mean value in class 1 (M = 29.53, SD = 7.72; M = 16.82, SD = 3.8) was significantly lower than in class 2 (M = 34.33, SD = 6.68; M = 19.42, SD = 3.4). The nature of the changes in CFFT values over time is associated with coping style. Coping styles are very valuable in the prediction of CNS arousal caused by exposure to +Gz stress.Biernacki MP, Lewkowicz R, Zieliński P, Wojtkowiak M. Coping and changes in arousal after exposure to +Gz load. Aerosp Med Hum Perform. 2017; 88(11):1034-1039.

Caratteristiche, tendenze e mutamenti della produzione scientifica sociologica nell'era della valutazione. Analisi esplorativa di un caso di studio

The paper analyzes, in a diachronic perspective, the sociological scientific production of Sapienza University. The type and languages of publication, and the co-authorship phenomenon are examined from 2004 to 2014, assuming that the implementation of the policies of evaluation of research (VTR, VQR) and regulatory changes on careers (comparative evaluations known as ASN) had an effect on the characteristics of the scientific production. The explorative analysis here presented, with all the limitations of a case study, shows (through the data extracted from the scientific production repository used by this University) different trends of changes in the characteristics of the contributions and in the different ways of publishing, in the decade 2004-2014. The results provide an interesting framework on sociological scientific production and - in relation to the implementation of the evaluation policies - evidence on the effects that the evaluation processes are producing on scientific communication.

Immune Response and Some Blood Constituents of Calves Produced From Primi- and Multi-Parous Friesian Cows Fed Yeast Culture

This study was conducted to evaluate the effect of dietary supplementation of dairy cows with yeast culture (YC) on immune transfer to their calves during first days after birth and on some blood constituents of calves from birth to 15 wk of age. Total of 15 Friesian cows (weighing 500-520 kg and 2-4 parities) and 15 Friesian heifers (weighing 400-420 kg) at late pregnancy (3 mo pre-partum) were used in this study. All experimental animals were randomly allocated in randomized design to three experimental groups (n=10, 5 cows and 5 heifers in each), fed on the same diet. Animals in 1st group were without treatment, while those in the second (T2) and third (T3) groups were orally administrated with 20 and 40 g/h commercial yeast culture (Thepax) for 90 days pre-partum and 90 days post-partum. After parturition, newborn calves were fed on colostrums of their dams, and then suckled milk up to weaning (105 d of age). Blood samples were collected from all newborn calves at first, second and third day after birth, then at 4, 8, 12 and 15 weeks of age. Hematological parameters including count of red (RBCs) and white (WBCs) blood cells, hemoglobin (Hb) concentration and packed cell volume (PCV) were determined in the whole blood. Concentration of total proteins (TP), albumin (AL), globulin (GL), total lipids (TL), cholesterol (CH), glucose (GLU), creatinine (CR), and thyroid hormone (T3) as well as AST and ALT activities were determined in blood serum. Results showed insignificant effect of dam parity (cows and heifers) on count of WBCs, Hb concentration and PCV value in the whole blood, serum concentration of immunoglobulines (IgG, IgM and IgA), TP, AL, GL, GLU, CR and T3, and ALT activity in serum of calves. Concentration of TL and CH, and AST activity were higher, while count of RBCs was lower (P<0.05) in calves of heifers than in those of cows. Concentrations of IgG, IgM and IgA were higher (P<0.05) in calves of T3 than in T1 by 32, 81 and 112%, respectively. Count of RBCs, Hb concentration and PCV value, and concentration of TP, AL and GL (P<0.05) and WBCs (P≥0.05) were higher in calves of T3 than in those of T1 and T2. Calves of T3 showed the highest (P<0.05) concentration of TL, CH and GLU and the lowest CR concentration and AST and ALT activity (P<0.05). Concentration of T3 was lower (P<0.05) in T2 and T3 than in T1. Concentration of IgG, IgM and IgA in serum and WBCs count of calves decreased (P≥0.05) on the 3rd day after birth. Count of RBCs, Hb concentration and PCV value increased (P<0.05) by advancing post-calving week. Only, TP, AL, TL, CH, GLU, CR and T3 concentrations and activity of AST and ALT showed different trends of changes by advancing post-calving week (P<0.05).In conclusion, pre- and post-partum yeast culture treatment at a level of 40 g/h/day for heifers and cows is able to enhance their newborn immunity response and improve calf performance with good health status, which allow for raising good male calves of breeding or female calves of milk production.

Diurnal changes in urban boundary layer environment induced by urban greening

Urban green infrastructure has been widely used for mitigating adverse environmental problems as well as enhancing urban sustainability of cities worldwide. Here we develop an integrated urban-land-atmosphere modeling framework with the land surface processes parameterized by an advanced urban canopy model and the atmospheric processes parameterized by a single column model. The model is then applied to simulate a variety of forms of green infrastructure, including urban lawns, shade trees, green and cool roofs, and their impact on environmental changes in the total urban boundary layer (UBL) for a stereotypical desert city, viz. Phoenix, Arizona. It was found that green roofs have a relatively uniform cooling effect proportional to their areal coverage. In particular, a reduction of UBL temperature of 0.3 °C and 0.2 °C per 10% increase of green roof coverage was observed at daytime and nighttime, respectively. In contrast, the effect of greening of street canyons is constrained by the overall abundance of green infrastructure and the energy available for evapotranspiration. In addition, the increase in urban greening causes boundary-layer height to decrease during daytime but increase at nighttime, leading to different trends of changes in urban air quality throughout a diurnal cycle.

Clinical Characteristics and Outcomes of Peritoneal Dialysis–Related Peritonitis with Different Trends of Change in Effluent white Cell count: A Longitudinal Study

Effluent white cell count (WCC) is among the important prognostic factors for peritonitis outcome, but its trend has never been studied. We aimed to explore the clinical characteristics and outcomes of peritonitis episodes having different trends in effluent WCC change in the first 5 days. For each peritonitis episode, we examined the patient's demographic and biochemical data, serial effluent WCC, and organisms cultured. Peritonitis-associated death and transfer to hemodialysis were defined as treatment failure. Based on the trend of effluent WCC in the first 5 days, we divided 190 peritonitis episodes into group A (WCC persistently declined), group B (WCC declined after a transient increase), group C (WCC increased after a transient decline), and group D (WCC persistently increased). In group A, peritonitis was caused mostly by gram-positive organisms, and effluent WCC declined the most quickly, leading to a good prognosis. Although the elevation of effluent WCC was prolonged in group B, and the infections were, compared with those in group A, more often caused by gram-negative organisms, outcomes were not worse. In group C, the effluent WCC was more likely to be higher than 100/μL on day 5, and the infection was, compared with those in groups A and B, less likely to be caused by gram-positive organisms. Accordingly, membership in group C independently predicted the worst outcome of peritonitis even adjusted for age, sex, and causative organism. Different trends of change in effluent WCC during the early stage of peritonitis represent different clinical patterns and outcomes. Further investigation for optimizing outcomes is required.

The ‘disappearance’ of Trypillia culture

The Trypillia-Cucuteni cultural complex over a period of almost 2000 years was an outstanding phenomenon east of the Carpathians, but it fell into decay. The Late period of Trypillia culture dates back to 3200–2700 BC and is represented by a few local types or so-called ‘post-Trypillia cultures’, all located in regions with different natural conditions and resources, from forest to steppe zones. Local features displayed different trends of change in the economy and material culture and also in social structures. The most conservative were groups with the highest development of social organisation and economy based on a division of labour, with proto-cities, as ‘points of rest’. On the borders of Trypillia culture, intercultural relations took on a special significance and led to changes in material culture and economy that materialised as a process of ‘disappearence’. It seems that these changes had a common point of departure – changes in the environment since 3200 BC.

Direct measurement of giant electrocaloric effect in BaTiO3 multilayer thick film structure beyond theoretical prediction

The electrocaloric (EC) effect of BaTiO3 multilayer thick film structure was investigated by direct measurement and theoretical calculation. The samples were prepared by the tape-casting method, which had 180 dielectric layers with an average thickness of 1.4 μm. The thermodynamic calculation based on the polarization-temperature curves predicted a peak heat adsorption of 0.32 J/g at 80 °C under 176 kV/cm electric field. The direct measurement via differential scanning calorimeter showed a much higher EC effect of 0.91 J/g at 80 °C under same electric field. The difference could result from the different trends of changes of electric polarization and lattice elastic energy under ultrahigh electric field.

Influence of preparation methods on the structures and properties for the blends between polyamide 6co6T and polyamide 6: Melt‐mixing and in‐situ blending

AbstractTwo blends between polyamide 6 (PA6) and Polyamide 6co6T (PA6co6T, a random copolymer between polyamide 6 and polyamide 6T) were fabricated by melt‐mixing on a twin‐screw extruder and the subsequent injection molding, or through the in‐situ polymerization of ε‐caprolactam in the presence of PA6co6T. As far as the former method is concerned, there exist an obvious decline of toughness and a slight increase in strength and modulus; however, for the latter, there appear a remarkable improvement in toughness and a simultaneous moderate increase in strength and modulus. A series of characterizations were carried out including scanning electron microscopy, wide‐angle X‐ray diffraction, polarized optical microscopy, differential scanning calorimetry, dynamic mechanical analysis, and Fourier transform infrared spectrometry. It is found that both blends exhibit single glass transition on DMA tan δ curves. However, contrary to that of the melt‐mixed blends, the glass transition temperature (Tg) of the in‐situ ones decreases with increasing PA6co6T content. It is suggested that different mixing levels are the main reasons. Moreover, the addition of PA6co6T containing linear rigid segments conducts remarkable refinement of spherulites for the blends. Significantly different changes in the crystallographic form, spherulite size, crystalline content and perfection due to the introduction of PA6co6T for the two blends are ascribed to their varied thermomechanical histories and the presence of interchange reaction only for the in‐situ blends. On the basis of the characterizations of the microstructures, the different trends of changes in the mechanical properties with the addition of PA6co6T for the two fabrication methods are discussed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 201–211, 2008

The effect of pressure on the fluorescence of a new type of light-emittingmaterial

The fluorescence properties of two nitrogen-containing poly-(phenylenevinylene)-related copolymers were investigated under high pressure. Because ofthe large difference in interchain interaction between these two copolymers, theemission states are different from each other. Under the perturbation introducedby compression, the emission intensity exhibits different trends of change.

Irradiation effects on secondary structure of protein induced by keV ions

Protein secondary structure changes by low-energy ion irradiation are reported for the first time. The selected system is 30 keV N + irradiation on bovine serum albumin (BSA). After irradiation at increasing fluences from 1.0×10 15 to 2.5×10 16 ion/cm 2, Fourier transform infrared spectra analysis was conducted. It was found that the secondary structures of BSA molecules were very sensitive to ion irradiation. Secondary conformations showed different trends of change during irradiation. With the increase of ion fluence from 0 to 2.5×10 16 ion/cm 2, the fraction of α-helix and β-turns decreased from 17 to 12%, and from 40 to 31%, respectively, while that of random coil and β-sheet structure increased from 18 to 27%, and from 25 to 30%, respectively. Possible explanations for the secondary conformational changes of protein are proposed.

Different trends of changes in heart rate variability in patients with anterior and inferior acute myocardial infarction.

Modifications in heart rate variability (HRV) parameters occur after acute myocardial infarction. The aim of this study was to evaluate the trend of HRV change during the acute phase and the first month after myocardial infarction, and establish whether they were affected by the anterior or inferior location of the infarction. The time-domain HRV measures of 59 patients with a first uncomplicated acute myocardial infarction were computed from 24-hour ECG recordings made on days 1, 2, 10, and 28 after hospital admission. At day 1, the mean RR cycle length (NN), the standard deviation of the NN intervals (SDNN), and the root mean square successive difference of NN intervals (RMSSD) were lower in the patients with anterior myocardial infarction. Although the parameters were similar in all of the patients at day 28, their behavior over time was different (P = 0.01): the SDNN in the patients with inferior myocardial infarction had decreased to the values found in anterior myocardial infarction patients by day 2 but, at day 10, both NN and SDNN tended to recover in both groups; RMSSD had diminished in both groups by day 2, but at day 10, had increased in the patients with anterior, but not in those with inferior myocardial infarction. These findings suggest that (1) in the very early phase of myocardial infarction, HRV is different in the two locations, (2) during the first hours of myocardial infarction patients with inferior location showed a greater vagal activity than patients with anterior location that became lower at day 10, and (3) the recovery of HRV is an early phenomenon in both groups, being already evident by the second week after myocardial infarction.

H-reflex changes in the course of amyotrophic lateral sclerosis

In this study the H-reflex and M-wave were evoked in a group of ALS patients, to correlate the findings with the clinical state, and to investigate whether a statistical approach for assessing H-reflex changes in the presence of a constant M-wave could be reproducible and helpful in monitoring the course of amyotrophic lateral sclerosis (ALS). The H-reflex and M-wave from the soleus muscle were evoked at different stimulus strengths in 35 patients with definite ALS during the course of their illness. The mean amplitude of the H-reflexes (H-mean) obtained in different sessions within an established range of mean M-response amplitude (M-mean) was calculated. For each patient, M-mean was made constant across sessions. H-mean showed high reproducibility and two different trends of changes which emerged in a 1 year follow-up within the population: a significant progressive increase and a steady decrease. When grouped on the basis of their H-mean trend, the patients did not differ in terms of any clinical variables considered. However, the group with progressive increase of H-mean showed a better prognosis. This study has shown that H-mean is effective in assessing the clinical course of ALS and could be useful in monitoring drug effects during clinical trials.