Short Step Research Articles

Chronopotentiometric method for assessing antioxidant activity: A reagentless measuring technique

A simple chronopotentiometric method designed for the estimation of the antioxidant activity of liquid samples was investigated. A carbon electrode with a thin immobilized redox mediator layer on its surface was used for detection. A two-step measuring protocol was used. Firstly, in a short potential-controlled step, the mediator was set to its oxidized state; then, in the second step, the electrode potential–time curve was recorded in open circuit mode. The initial slope of this curve served as the analytical signal. It is clear that a higher antioxidant concentration produced a higher slope. The performance of adsorbed and electropolymerized Meldola Blue redox mediator layers formed on glassy carbon electrodes was investigated and compared. L-ascorbic acid was used as a sample antioxidant in this study.

MeOTf‐Catalyzed Intramolecular Acyl‐Cyclization of Aryl Isocyanates: Efficient Access to Phenanthridin‐6(5H)‐one and 3,4‐Dihydroisoquinolin‐1(2H)‐one Derivatives

AbstractMeOTf‐catalyzed intramolecular acyl‐cyclization of aryl isocyanates has been realized to provide (NH)‐phenanthridinones and lactams under metal‐free conditions. A variety of functional groups are tolerated in their scaffolds with good to excellent yields. The reaction could be carried to gram scale and a range of natural alkaloids, such as crinasiadine, benzophenidine alkaloid (ZYH005), N‐methylcrinasiadine, and trisphaeridine could be synthesized directly or in short steps with high yields.

Le diagramme en scène Mouvement, geste et écriture

From the diagram, which inscribes the line (διά-γράφειν), to the choreography (χορεία-γραφία), which inscribes the choir into the written form, we remark but a short step from the scène of the dance to the scène of the writing. The writing of dance, and likewise the writing of the body, makes the invisible visible within the movement. Bridging between notation, as capacity for mobilisation of new intuitions, and diagrammatization of forms and movements to compel the thought of new gestures, the diagram stands out as a scène or ‘picture’ whose axes (points, lines, arrows, circles, volumes…) simultaneously structure mobility in order to grasp the pulsating movement. The twentieth-century artistic avant-gardes will not remain indifferent to this ideography that, through leap and condensation, makes the materialization of the idea, the idea in the writing, possible.

The Diagram on Stage Movement, Gesture and Writing

From the diagram, which inscribes the line (διά-γράφειν), to the choreography (χορεία-γραφία), which inscribes the choir into the written form, we remark but a short step from the scène of the dance to the scène of the writing. The writing of dance, and likewise the writing of the body, makes the invisible visible within the movement. Bridging between notation, as capacity for mobilisation of new intuitions, and diagrammatization of forms and movements to compel the thought of new gestures, the diagram stands out as a scène or ‘picture’ whose axes (points, lines, arrows, circles, volumes…) simultaneously structure mobility in order to grasp the pulsating movement. The twentieth-century artistic avant-gardes will not remain indifferent to this ideography that, through leap and condensation, makes the materialization of the idea, the idea in the writing, possible.

ARRT Development for the Upcoming Human Exploration Missions

AbstractThe health risks of space radiation present big challenges to space exploration, with the possibility of large Energetic Solar Particle Events (ESPEs) inducing Acute Radiation Sickness (ARS) during upcoming Artemis missions. An operational software Acute Radiation Risks Tool (ARRT) was developed to directly use measurements from onboard dosimeters to project organ doses during times of increased radiation exposure, so that any possible ARS risks of the astronauts can be modeled and monitored in real time using a data stream at the astronaut location. To enable ARRT to handle variant scenarios of any possible ESPEs in an automatic manner for mission operation, two data sets were employed in developing its modules, one involving historical solar protons recorded over the past four decades and the other using the real‐time telemetry readings of dosimeters onboard International Space Station (ISS). Though vastly different in terms of data cadence, smoothness, and data gaps, all events in these data sets can be correctly processed to output organ doses and ARS risks and generate flight notes for communication within the Flight Control Team (FCT). All these tasks are completed with close interactions between multiple modules developed with many state‐of‐the‐art facilities of full stack web applications. This work demonstrates that ARRT meets the requirement to project radiation exposure and to provide clinical guidelines in very short time steps as the ESPE unfolds, even for the longest event in data sets, making this tool eligible to be tested during the upcoming unmanned Artemis mission and utilized in future space exploration.

Effect of active resisted 30 m sprints upon step and joint kinematics and muscle activity in experienced male and female sprinters

ABSTRACT This study compared the kinematics (step and joint) and muscle activity of unresisted and active resisted 30 m sprints with different loads (10–40% body mass) in experienced male and female sprinters. Step kinematics were measured using a laser gun and contact mat in 28 male and female participants during unresisted 30 m sprint, and sprints with 10–40% of body mass (BM) active resistance, while peak angular velocities of lower limb was measured, together with muscle activation of nine muscles. Increased resisted loads resulted in slower 30 m times, as a result of lower step velocity mainly caused by shorter step lengths and frequencies, flight times and longer contact times, with a greater effect on women than on men. These step kinematic differences, due to increasing load were accompanied with lower peak joint movements. However, gender differences were only found for peak plantar flexion with unresisted and 10% BM resisted sprints. Furthermore, increasing load decreased calf and hamstring muscles activity, while medial vastus activity increased. Based upon these findings, it was concluded that when introducing active resisted sprints, women should sprint with approximately 10% less active loads than men to have equal step and joint kinematics development over the sprint distance.

Assessing Functional Disability in Glaucoma: The Relative Importance of Central Versus Far Peripheral Visual Fields.

PurposeTo evaluate the importance of central versus far peripheral visual field (VF) loss in assessing disability in glaucoma.MethodsIn total, 231 patients with glaucoma or suspected glaucoma completed 24-2 VF testing and automated peripheral VFs using the suprathreshold 30- to 60-degree pattern. Questionnaires assessed fear of falling (FoF), quality of life (QOL), instrumental activities of daily living (IADLs), and driving habits; nonsedentary time, reading speed, and gait were objectively measured. Multivariable regression models analyzed the effect of central VF and/or peripheral VF damage on each outcome.ResultsIn models including both central and peripheral VF damage (independent effects), greater central, but not peripheral, VF damage was associated with greater FoF, worse QOL, fewer daily steps, and difficulty with IADLs (P < 0.02 for central; P > 0.5 for peripheral). For gait measures, greater peripheral, but not central, damage was associated with shorter steps and shorter strides, as well as greater variability in step length (P < 0.03 for peripheral; P > 0.14 for central). Model R2 values were not substantially higher (less than 5% additional explained variability) for models including both central and peripheral VF damage as compared to the best models incorporating only one region of VF damage (i.e., central or peripheral).ConclusionsThe relative importance of central 24 degrees versus more peripheral VF damage differs across functional domains in patients with glaucoma. Central damage is more strongly associated with most disability outcomes, although peripheral damage is more associated with specific gait measures. Studies examining the relative importance of various VF regions should assess functional domain separately and eschew integrated measures of quality of life/activity limitation.

Gait Disturbance Improvement and Cerebral Cortex Rearrangement by Acupuncture in Parkinson’s Disease: A Pilot Assessor-Blinded, Randomized, Controlled, Parallel-Group Trial

Background Parkinson’s disease (PD) leads to impaired mobility and limited independence. Objective We investigated the effects of acupuncture on gait disturbance and analyzed hemodynamic changes caused by acupuncture in the cerebral cortex of patients with PD. Methods Participants (n = 26) with gait disturbance due to PD were randomly assigned to the intervention (acupuncture twice a week for 4 weeks + conventional therapy) or control (conventional therapy) groups. We analyzed gait parameters using the GAITRite system and hemodynamic responses in the cerebral cortices using functional near-infrared spectroscopy, Unified Parkinson’s Disease Rating Scale (UPDRS) scores, neurotransmitter levels, as well as the immediate effects of acupuncture in patients with PD. Results The participants tended to walk with hypometric gait (high cadence, short steps) overground. After acupuncture treatment, those in the intervention group showed a significant reduction in cadence and the UPDRS scores involving “walking and balance” compared with those in the control group (P = .004 and P = .020, respectively); the stride, swing, and single support times were significantly increased (P = .006, P = .001, and P = .001, respectively). Oxyhemoglobin levels in the intervention group while walking on a treadmill were significantly increased in the prefrontal and supplementary motor areas. The oxyhemoglobin levels in the prefrontal cortex and swing time revealed significant positive correlations. Conclusions Our findings indicated that acupuncture tended to improve hypometric gait and rearranged activation of the cerebral cortex. Thus, acupuncture may be a useful complementary treatment for gait disturbance, including hypometric gait, in patients with PD. Trial Registration Number. Clinical Research Information Service (KCT0002603), https://cris.nih.go.kr/cris/index.jsp

Discrete event optimization of a vehicle charging station with multiple sockets

The relevance and presence of Electric Vehicles (EVs) are increasing all over the world since they seem an effective way to fight pollution and greenhouse gas emissions, especially in urban areas. One of the main issues related to EVs is the necessity of modifying the existing infrastructure to allow the installation of new charging stations (CSs). In this scenario, one of the most important problems is the definition of smart policies for the sequencing and scheduling of the vehicle charging process. The presence of intermittent energy sources and variable execution times represent just a few of the specific features concerning vehicle charging systems. Even though optimization problems regarding energy systems are usually considered within a discrete time setting, in this paper a discrete event approach is proposed. The fundamental reason for this choice is the necessity of limiting the number of the decision variables, which grows beyond reasonable values when a short time discretization step is chosen. The considered optimization problem regards the charging of a series of vehicles by a CS connected with a renewable energy source, a storage element, and the main grid. The objective function to be minimized results from the weighted sum of the (net) cost for purchasing energy from the external grid, the weighted tardiness of the services provided to the customers, and a cost related to the occupancy of the socket during the charging. The approach is tested on a real case study. The limited computational burden allows also the implementation in real-case applications.

Neural Correlates of Freezing of Gait in Parkinson's Disease: An Electrophysiology Mini-Review.

Freezing of gait (FoG) is a disabling symptom characterized as a brief inability to step or by short steps, which occurs when initiating gait or while turning, affecting over half the population with advanced Parkinson's disease (PD). Several non-competing hypotheses have been proposed to explain the pathophysiology and mechanism behind FoG. Yet, due to the complexity of FoG and the lack of a complete understanding of its mechanism, no clear consensus has been reached on the best treatment options. Moreover, most studies that aim to explore neural biomarkers of FoG have been limited to semi-static or imagined paradigms. One of the biggest unmet needs in the field is the identification of reliable biomarkers that can be construed from real walking scenarios to guide better treatments and validate medical and therapeutic interventions. Advances in neural electrophysiology exploration, including EEG and DBS, will allow for pathophysiology research on more real-to-life scenarios for better FoG biomarker identification and validation. The major aim of this review is to highlight the most up-to-date studies that explain the mechanisms underlying FoG through electrophysiology explorations. The latest methodological approaches used in the neurophysiological study of FoG are summarized, and potential future research directions are discussed.

Smart UV spectrophotometric methods based on simple mathematical filtration and classical methods for the simultaneous determination of tamsulosin and solifenacin: A comparative study of efficacy and spectral resolution

Treatment protocols combining tamsulosin and solifenacin proved better management of the complicated urinary tract symptoms. The pharmaceutical preparations of tamsulosin and solifenacin suffered from the high difference in their ratio, 0.4 mg tamsulosin and 6 mg solifenacin, and strong spectral overlap. Here, we developed four simple, accurate and selective spectrophotometric methods based on simple mathematical manipulations. These methods require the simplest mathematical filtration using short steps performed using built-in functions of the spectrophotometer operating software utilizing zero-order or derivative spectra. These methods are namely absorption correction method (ACM), induced dual-wavelength (IDW), absorptivity factor method (AFM) and first derivative method (D1). The linear ranges were 15–70 µg/ml and 100–1200 µg/ml for TAM and SFN, respectively. The limits of quantitation were in the range of 3.8–4.05 µg/ml and 23.34–59.05 µg/ml, while the limits of detection were in the range of 1.25–1.34 µg/ml and 7.7–24.6 µg/ml for TAM and SFN, respectively. All validation parameters investigated as per ICH guidelines. A statistical comparison executed for the proposed methods with each other and with the reported methods showed no significant difference between the proposed and the reported methods.

Short Cantilever Rock Beam Structure and Mechanism of Gob-Side Entry Retaining Roof in Reuse Period

In the reuse stage of a gob-side entry retaining, failure of the structure and stability of the main roof have a significant effect on the safety of the advanced support and ventilation space at the working face. In this study, field investigation, theoretical analysis, and industrial experimentation were performed to analyse the fracture characteristics and formation process of the gob-side entry retaining roof during the reuse period. A dynamic-equilibrium mechanical model of the main roof structure is presented and the formation mechanisms of different types of short cantilever rock beam structures are clarified. The following major conclusions are drawn: (1) Three types of short cantilever rock beam structures occur in the main roof of a gob-side entry retaining during the reuse period, namely, the “short cantilever-articulated rock beam” structure, “short cantilever step rock beam (type I)” structure, and “short cantilever step rock beam (type II)” structure. (2) The stability criterion for these three short cantilever rock beam structures was also determined; that is, when the sliding instability coefficient K ≥ 1, the short cantilever-articulated rock beam structure will form, and when the sliding instability coefficient K &lt; 1, the short cantilever step rock beam (type I or II) will form. (3) The governing law for the thicknesses of the main roof, immediate roof, and coal seam of the short cantilever rock beam structure was clarified; namely, the K-value gradually increases with increases in the thickness of the coal seam, drops sharply and then decreases gradually with increases in the thickness of the main roof, and decreases slowly with increases in the thickness of the immediate roof. The research results were validated at the gob-side entry retaining project in the Huainan mining area and have theoretical significance and reference value for roadway support projects with similar conditions.

Gait characteristics of children with Williams syndrome with impaired visuospatial recognition: a three-dimensional gait analysis study.

Williams syndrome (WS) is a genetically based neurodevelopmental disorder characterized by intellectual disability and impaired visuospatial recognition. The aim of this study was to analyze the gait characteristics of WS children with impaired visuospatial recognition using a three-dimensional gait analysis (3DGA) to clarify the gait adaptation needed to compensate for it. 3DGA was performed in 8 WS children with impaired visuospatial recognition (mean age, 11.8years) and 9 age-, sex-, height-, and weight-matched controls. Clinical data, fundamental motor tests, and gait variables while walking on a flat surface and walking up a mat were compared between the two groups, and the correlations between variables were analyzed in the WS children. WS children showed impairment of balance function without muscle weakness. In walking on a flat surface, the WS group showed reduced walking speed, short step length, increased variability of step length, increased knee flexion throughout the stance phase, increased horizontal pelvic range of motion (ROM), and a low Gait Deviation Index and a high Gait Profile Score, which are indices of gait quality. In walking up a mat, the WS group showed further reduced walking speed and decreased sagittal hip flexion and ankle dorsiflexion ROM in the swing phase. Impaired balance function was significantly correlated with increased variability of step length and decreased sagittal ankle dorsiflexion ROM in the swing phase. The detailed gait pattern of WS children with impaired visuospatial recognition was presented. These findings show that impaired visuospatial recognition and balance function contribute to gait adaptation.

Preparation of Nafion Membranes for Reproducible Ammonia Quantification in Nitrogen Reduction Reaction Experiments

AbstractThis study highlights the importance of following a strict protocol for Nafion membrane pretreatment for electrochemical nitrogen reduction reaction experiments. Atmospheric ammonia pollution can be introduced to the experimental setup through membranes and interpreted falsely as catalysis product from N2. The sources of ammonia contamination vary drastically between locations worldwide and even within the same location between days depending on temperature, wind direction, fertilizer use, and manure accumulation in its vicinity. The study shows that significant amounts of ammonium is accumulated in the membranes after commonly practiced pretreatment methods, where the amount depends on the ammonia concentration in the surrounding of the experiment. Therefore, we introduce a new pretreatment method which removes all the ammonium in the membrane. The membranes can be stored for several days but a short final step in the method needs to be carried out right before NRR experiments.

Preparation of Nafion Membranes for Reproducible Ammonia Quantification in Nitrogen Reduction Reaction Experiments.

This study highlights the importance of following a strict protocol for Nafion membrane pretreatment for electrochemical nitrogen reduction reaction experiments. Atmospheric ammonia pollution can be introduced to the experimental setup through membranes and interpreted falsely as catalysis product from N2 . The sources of ammonia contamination vary drastically between locations worldwide and even within the same location between days depending on temperature, wind direction, fertilizer use, and manure accumulation in its vicinity. The study shows that significant amounts of ammonium is accumulated in the membranes after commonly practiced pretreatment methods, where the amount depends on the ammonia concentration in the surrounding of the experiment. Therefore, we introduce a new pretreatment method which removes all the ammonium in the membrane. The membranes can be stored for several days but a short final step in the method needs to be carried out right before NRR experiments.

3D gait analysis, haemophilia joint health score, leg muscle laterality and biomarkers of joint damage: A cross-sectional comparative assessment of haemophilic arthropathy.

Introduction3D gait analysis has been proposed as a reproducible and valid method to assess abnormal gait patterns and to monitor disease progression in patients with haemophilia (PWH).AimThis study aimed at comparing Gait Deviation Index (GDI) between adult PWH and healthy controls, and at assessing the agreement between outcome measures of haemophilic arthropathy.MethodsMale PWH aged 18‐49 years (prespecified subgroups: 18‐25 vs 26‐49 years) on prophylactic replacement therapy, and male healthy age‐matched controls passed through a cross‐sectional assessment panel. Besides the 3D gait analysis derived GDI, secondary outcomes included kinematic, kinetic and spatio‐temporal gait parameters, the Haemophilia Joint Health Score (HJHS), electric impedance derived leg muscle laterality and inflammatory biomarkers.ResultsPatients with haemophilia (n = 18) walked slower, in shorter steps and accordingly with less functional range of motion in the hips and ankles, as compared to healthy controls (n = 24). Overall, PWH did not differ significantly in GDI and specific gait parameters. PWH had a higher mean HJHS (18.8 vs 2.6, P = .000) and leg muscle laterality (4.3% vs 1.5%, P = .004). A subgroup analysis revealed progressed gait pathology in PWH aged 26‐49 years (not statistically significant). Leg muscle laterality was strongly correlated with HJHS (r = .76, P = .000), whereas GDI just moderately (r = −.39, P = .110). PWH had higher levels of the inflammatory markers CRP and IL‐6.ConclusionProgressed gait pathology was found in PWH, mainly those aged 26‐49 years. Leg muscle laterality correlated strongly with HJHS and was identified as a promising tool for detecting progression and physiological consequences of haemophilic joint arthropathy.

S3414 Esophageal Dysfunction in Systemic Sclerosis: A Rare Etiology of Heartburn

INTRODUCTION: Heartburn is a prevalent condition with obesity, old age, and smoking identified as common risk factors. Systemic sclerosis with esophageal involvement is a rare etiology. Here we present a case of systemic sclerosis which presented with the symptoms of heartburn and regurgitation. CASE DESCRIPTION/METHODS: A 40-year-old female patient presented to our clinic with complaints of persistent heartburn and regurgitation for the last 1 month. She had a past medical history of rheumatoid arthritis and systemic sclerosis. Her medications included methotrexate, leflunomide, and piroxicam. She was also given daily oxygen therapy for her lung complaints. For the past 6 months, she had on and off heartburn symptoms which were relieved by over the counter antacids. However, for the last 1 month, she had a persistent burning sensation in her chest and epigastric region. She also complained of regurgitation and occasional vomiting. These symptoms worsened after food intake and at night which caused her to avoid meals. There was no history of hematamesis, black-colored stools or dysphagia. Her vitals were normal. She walked with short steps, had skin tightness and conjunctival pallor. Her Hemoglobin was 9.8 g/dl with mean corpuscular volume 66 fL. Her endoscopy showed dilated esophagus proximal to stricture at the lower end of the esophagus (Figure 1). The lower third of the esophagus showed changes consistent with reflux esophagitis. Other positive findings included incompetent lower esophageal sphincter, hyperemic stomach mucosa and dilated second portion of the duodenum. Based on these findings, the patient was diagnosed as a case of peptic stricture most likely due to reflux esophagitis. Systemic sclerosis probably contributed to her esophageal problems. She was treated with high dose proton pump inhibitors and prokinetics. She was advised to elevate the head end of the bed and abstain from lying down immediately after her meals. Follow-up after 2 weeks showed improvement in her symptoms. DISCUSSION: Systemic sclerosis is a multisystem connective tissue disorder. Its pathogenesis revolves around inappropriate immunological responses which result in excessive collagen deposition in the skin and internal organs like the esophagus. Esophageal involvement is diagnosed by endoscopy and esophageal pH monitoring. This condition is usually managed by lifestyle changes and medical treatment by prokinetics and proton pump inhibitors.Figure 1.: Endoscopy image shows a dilated esophagus proximal to a stricture at the lower end of esophagus. The lower esophageal sphincter is also incompetent.

DIFFERENCES IN GAIT PATTERNS BETWEEN PATIENTS WITH SWEDD AND NORMAL SUBJECTS

Whether gait assessment can distinguish patients with scans without evidence of dopaminergic deficit (SWEDD) from normal individuals remains unclear. In the present study, the gait patterns in SWEDD patients and normal individuals were investigated. 10 patients with SWEDD and 10 healthy normal subjects were recruited. A GaitRite linear walkway was used to quantitatively assess level walking. Eight spatiotemporal variables were selected for comparison between two groups. For statistical analysis, independent sample [Formula: see text]-tests were performed to compare between normal individuals and SWEDD patients. Compared with normal individuals, SWEDD patients exhibited a shorter step length ([Formula: see text]). In addition, SWEDD patients showed a wider distribution of heel-to-heel (HH) base of support compared with normal individuals ([Formula: see text]). SWEDD patients had a tendency to deteriorated gait speed ([Formula: see text]) and double-limb support cycle ([Formula: see text]). These results indicate that SWEDD patients adopted a walking strategy that utilized increased step length and width to compensate for deteriorated dynamic balance. These results indicate that quantitative gait assessment could be useful for more accurate diagnosis of SWEDD patients. In addition, understanding clinical features of SWEDD patients might contribute to efficient interventions.

Algo-Functional Indexes and Spatiotemporal Parameters of Gait after Sacroiliac Joint Arthrodesis.

Aims of the study were to evaluate the reliability and validity of the Italian version of the Majeed and Iowa questionnaires and to investigate the long-term surgical outcomes following sacroiliac joint arthrodesis. Twenty one patients who underwent a sacroiliac joint arthrodesis and 21 healthy subjects were evaluated. The experimental procedure consisted of gait analysis and a physical activity assessment (in both groups) and of administration of outcome questionnaires and pain assessment (in the patient group). The Majeed and Iowa questionnaires showed excellent reliability, excellent (for the Majeed questionnaire) and good (for the Iowa questionnaire) construct validity, and poor convergent validity (for both questionnaires) relative to walking speed. Most of the patients reported no pain and minimum pain-related disability and their physical activity profile was comparable to healthy controls. Patients showed an impaired walking performance (i.e., they walked slower and using shorter steps) compared with healthy controls. Long-term walking pattern abnormalities following sacroiliac joint arthrodesis may occur despite excellent clinical results. Given their excellent reliability and construct validity, the Majeed and Iowa questionnaires can be used in combination with the assessment of spatiotemporal gait parameters for the prognostic assessment and/or follow-up of surgical patients.

A Few Steps Ahead to Select ACE2 in Pediatric COVID-19 Treatment: A Review of Literature

This review study aimed to examine the relationship between Coronavirus (COVID-19) and its uses in renin-angiotensin-aldosterone system (RAAS) to infect the patient using the related studies in this regard. Finally, the logical method of using the related medicine, and the benefits and harms of using these Medications will be indicated in the treatment of novel coronavirus. It is hoped that a short step will be taken in the attitude of scientists to plan further studies on the pediatric treatment of upgrading COVID-19.