Weight Shift Research Articles

The Square Root Problem and Subnormal Aluthge Transforms of Recursively Generated Weighted Shifts

The Square Root Problem and Subnormal Aluthge Transforms of Recursively Generated Weighted Shifts

Evolving Consumer Preferences: The Role of Attribute Shifts in Online Travel Agency Satisfaction and Loyalty

The attributes that people consider when selecting an online travel agency (OTA) change over time, affecting how consumer satisfaction and loyalty evolve. However, attribute weight shifts in subsequent OTA visits cannot be determined using a cross-sectional approach. Thus, this study investigates the linkage dynamics between satisfaction and loyalty intentions as OTA attribute weights shift over time. We also assess the moderating effect of sales promotions on this linkage across subsequent OTA visits. Using a two-time-lag survey methodology (T1 and T2), we obtain 329 usable data. Our findings demonstrate that the link between satisfaction and loyalty intentions strengthens as customers gain more experience with an OTA. While price and post-service quality weights increase sharply, the weights of security and ease of use decrease. Furthermore, our findings show that the moderating effect of sales promotions does not appear in the early stages of a consumer’s experience with an OTA. Our research is the first to offer a complete understanding of the role of sales promotions based on the satisfaction–loyalty mechanism, considering a broad range of OTA selection attributes.

Evaluation of the balance system in amateur kickboxers

Abstract Background Kickboxing is defined as an eclectic combat sport created by combining close combat practices. While the effect of kickboxing on balance function may seem evident, controlled studies that investigate the impact of kickboxing on static and dynamic balance using objective tests are limited. Objective The primary aim of this study was to evaluate the effects of kickboxing on the development of static and dynamic balance in amateur kickboxers using objective tests. Specifically, we sought to assess how kickboxing training influences postural abilities and balance systems. Methods A total of 20 amateur kickboxers between ages 18 and 26 years (mean age, 21.6 ± 5.65 years) and 20 healthy subjects between ages 19 and 25 years (mean age, 21.3 ± 1.41 years) who had no previous experience with kickbox sports training were recruited. The sensory organization test (SOT), adaptation test (ADT), limit of stability (LOS), rhythmic weight shift (RWS) test, weight bearing/squat (WBS) test, and unilateral stance (US) test of the computerized dynamic posturography (CDP) were used to evaluate both groups. All these subtest results were compared between amateur kickboxers and the control group. All subtest results were compared between amateur kickboxers and the control group using independent sample t-tests. An alpha level of 0.05 was set for statistical significance. Results A statistically significant difference was found in the weight bearing/squat (WBS) and limit of stability (LOS) subtest results of the CDP between amateur kickboxers and the control group compared to the control group in amateur kickboxers (p < 0.05). Conclusions An increase in LOS and WBS skills was observed in the amateur kickboxers who participated in this study when compared to similar-aged individuals who did not participate in kickboxing. These balance differences may be greater in more elite-level kickboxers who have trained for longer. In addition, other balance parameters may also improve with longer periods of exposure and increasing skill complexity performed at more elite levels.

Infrastructures and International Relations: A Critical Reflection on Materials and Mobilities

Abstract In a world of accelerated movements, this article examines how infrastructures matter in international relations. We first show that the International Relations (IR) discipline has relegated infrastructures to the background of their studies and treated them as passive tools despite their forcible role in the establishment of the modern state system. By adopting a sociological definition of “the international,” this article emphasizes the centrality of materials and mobilities in thinking about the international and calls for a novel infrastructural lens in the IR discipline. We argue that infrastructures provide crucial mechanisms for forging the distinctions between units that constitute the international as a separate realm. We outline how infrastructures continuously transform this realm through re-scaling and re-ordering spaces, polities, and people. In the meantime, infrastructures are at the heart of social processes, which generate knowledge practices that constitute the international. They inscribe themselves in discourses, produce meaning, and shape identities, and they are thus part of the ideational underpinning of the international. We conclude by advocating a shift in the analytical weight of materials in IR, premised on an interdisciplinary dialogue, and suggest a theoretical and methodological recalibration of the discipline’s treatment of infrastructures.

The Salience of Less Important Product Attributes

ABSTRACTThe significance of product attributes, as reflected in online reviews during the initial purchase, may undergo changes following positive or negative product usage experiences. The purpose of this research was to investigate whether positive or negative product consumption experiences influence shifts in the perceived importance of product attributes and subsequent product choices, based on online quality ratings by attributes. A series of experiments demonstrated that the importance associated with an attribute's expectation in the pre‐purchase process shifted after a negative consumption experience with that attribute. The results showed that a change in both attribute importance and product choice following a negative attribute experience. A less important attribute that malfunctioned during the consumption experience became more crucial in the subsequent purchase (Study 1). However, this shift in importance may not be universal for all attributes; it was observed only when the attribute was moderately important (Study 2). This study contributes valuable empirical findings to the existing literature on online reviews by highlighting dynamic shifts in the importance weight of product attributes. E‐commerce practitioners are encouraged to allow formal purchasers to leave product reviews without time constraints, providing a platform for reflecting users' lifelong consumption experiences.

Peripheral neuropathy, an independent risk factor for falls in the elderly, impairs stepping as a postural control mechanism: A case-cohort study.

Peripheral neuropathies perturbate the sensorimotor system, causing difficulties in walking-related motor tasks and, eventually, falls. Falls result in functional dependency and reliance on healthcare, especially in older persons. We investigated if peripheral neuropathy is a genuine risk factor for falls in the elderly and if quantification of postural control via posturography is helpful in identifying subjects at risk of falls. Seventeen older persons with a clinical polyneuropathic syndrome of the lower limbs and converging electrophysiology were compared with 14 older persons without polyneuropathy. All participants were characterized via quantitative motor and sensory testing, neuropsychological assessment, and self-questionnaires. Video-nystagmography and caloric test excluded vestibulocochlear dysfunction. For further analysis, all subjects were stratified into fallers and non-fallers. Overall, 28 patients underwent computerized dynamic posturography for individual fall risk assessment. Regression analyses were performed to identify risk factors and predictive posturography parameters. Neuropathy is an independent risk factor for falls in the elderly, while no differences were observed for age, gender, weight, frailty, DemTect test, timed "Up & Go" test, and dizziness-related handicap score. In computerized dynamic posturography, fallers stepped more often to regain postural control in challenging conditions, while the Rhythmic Weight Shift test showed a lack of anterior-posterior bidirectional voluntary control. Our study confirms peripheral neuropathy as a risk factor for older persons' falls. Fallers frequently used stepping to regain postural control. The voluntary control of this coping movement was impaired. Further investigations into these parameters' value in predicting the risk of falls in the elderly are warranted.

A classification of polyharmonic Maaß forms via quiver representations

We give a classification of the Harish-Chandra modules generated by the pullback to SL2(R) of polyharmonic Maaß forms for congruence subgroups of SL2(Z) with exponential growth allowed at the cusps. This extends results of Bringmann–Kudla in the harmonic case. While in the harmonic setting there are nine cases, our classification comprises ten; A new case arises in weights k>1. To obtain the classification we introduce quiver representations into the topic and show that those associated with polyharmonic Maaß forms are cyclic, indecomposable representations of the two-cyclic or the Gelfand quiver. A classification of these transfers to a classification of polyharmonic weak Maaß forms. To realize all possible cases of Harish-Chandra modules we develop a theory of weight shifts for Taylor coefficients of vector-valued spectral families. We provide a comprehensive computer implementation of this theory, which allows us to provide explicit examples.

A Comparison Between Open Kinetic and Closed Kinetic Chain Exercises Along with Conservative Treatment in Grade-I ACL Injury in Sprinters: A Randomized Controlled Trail

Background:Anterior Cruciate Ligament (ACL) injury is most common in sports players such as soccer, basketball, sprinters, which causes alleviated strength in quadriceps muscles, and Range of Motion (ROM) of Knee Joint, and along with this, decrease in efficiency of knee that impacts person’s Activity of daily living (ADL). So, after ACL injury, Rehabilitation protocol plays a great role in maintaining knee ROM, increases the strength of quadriceps muscles. This study aims to compare the effect of open kinetic chain exercises and closed kinetic chain exercises and compare to asses which type of protocol is much efficient for ACL-Injury rehab protocol. Methodology: A comparative study was done over 50 male sprinters of 18-25 years old to assess the effect of Open Kinetic chain exercises (OKC) and closed kinetic chain exercises (CKC). Study was divided into 2 groups: OKC group and CKC group. In OKC Group, subject has to do flexor-extensor bench, isotonic quadriceps exercise and long leg press-off exercises with the conventional physiotherapy whereas in CKC group, subjects has to do wall sits exercises, standing weight shift, one-legged dips exercise, and squatting lunges along with the conventional physiotherapy. Each exercise was performed with 3 sets of 20 repetition, 3 days/week for 45 days. The data was collected from various academies of Satara, Maharashtra after obtaining the ethical permission. Subjects were explained about the procedure and protocol of research. ROM, Numeric Pain Rating Scale (NPRS) and Knee Injury and Osteoarthritis Outcome Score (KOOS) scale were used as Outcome measures. Readings were noted on Day 0 and Day 45. The data was analyzed by using JASP Software. Results: 25 subjects were there in both groups, with the mean age of 23.4 years in CKC group whereas the mean age is 23.44 in OKC group. The mean value of NPRS in OKC group is 4.280±0.843 and that of CKC groups is 4.160±0.624. And the mean value of Knee ROM in CKC group is 118±5 while that of in OKC group is 107.2±4.52. Conclusion: In summary, this study highlights the importance of a tailored rehabilitation program combining OKC and CKC exercises for Grade-I ACL injuries in sprinters. Both exercise types play a crucial role in restoring knee function and strength. As per our study, CKC exercises are better than OKC exercises. So, CKC exercises should be incorporated into rehabilitation program of grade-I ACL injuries.

Combined effects of functional task training with electrical stimulation on motor abilities and balance in children with diplegia

BackgroundChildren with spastic diplegic cerebral palsy (CP) often demonstrate gluteus medius weakness that causes balance deficits and frequent falling during walking.PurposeThe aim of the study was to evaluate the combined effects of functional task training with electrical stimulation of bilateral hip abductor muscles on motor abilities (standing and walking) and balance in children with spastic diplegic CP.MethodsThirty children with diplegic CP of both sexes whose ages ranged from 7 to 10 years were assigned randomly into two equal groups. For both groups, motor abilities were assessed by gross motor function measure (GMFM), and balance (static and dynamic) was assessed by the humac balance system before and after the study. The control group received a functional training program focusing on standing walking and balance exercises. While children in the study group received the same functional training program with bilateral electrical stimulation of gluteus medius muscles for 50 min. The treatment program for both groups was conducted for 3 sessions/week for 8 weeks.ResultsThere were statistically significant differences between the control and study group post-treatment in GMFM as well as the center of pressure test and weight shift test in favor of the study group (p < 0.05).ConclusionUsing functional task training with electrical stimulation for treatment of children with spastic diplegic CP have significant effects on improving their motor abilities and balance that suggests using it in rehabilitation for these children.

Intriguing Low-Temperature Phase in the Antiferromagnetic Kagome Metal FeGe.

The properties of kagome metals are governed by the interdependence of band topology and electronic correlations resulting in remarkably rich phase diagrams. Here, we study the temperature evolution of the bulk electronic structure of the antiferromagnetic kagome metal FeGe using infrared spectroscopy. We uncover drastic changes in the low-energy interband absorption at the 100K structural phase transition that has been linked to a charge-density-wave (CDW) instability. We explain this effect by the minuscule Fe displacement in the kagome plane, which results in parallel bands in the vicinity of the Fermi level. In contrast to conventional CDW materials, however, the spectral weight shifts to low energies, ruling out the opening of a CDW gap in FeGe.

The effect of strabismus surgery on the dynamic balance in children with strabismus

ABSTRACT Purpose: To evaluate the effect of strabismus surgery on dynamic balance by using computerized dynamic posturography in children with strabismus. Methods: This study was designed as a prospective observational study. Hearing tests and complete ophthalmological examinations were performed for all subjects. Patients with moderate and severe amblyopia, hearing loss at any level, and/or any suspicion of balance impairment were excluded from the study. Postural stability evaluation was performed by computerized dynamic posturography including sensory organization test, adaptation test, and rhythmic weight shift test. All tests were applied preoperatively and in the postoperative 1st and 3rd months, respectively. Results: Fifteen female and twelve male pre-adolescents aged between 7 and 12 (9.67 ± 1.62 years) were included in the current study. In the sensory organization test, the preoperative visual ratio percentages (73.19 ± 14.95%) improved statistically significantly at the postoperative 1st and 3rd months (78.59 ± 16.21% and 81.44 ± 14.18; p = .026, p = .021, respectively). The preoperative toes up (110.66 ± 33,48) and toes down (81.46 ± 28.36) adaptation tests improved statistically significantly in the postoperative 3rd month (88.74 ± 20.94 and 63.36 ± 16.03; p < .001, p = .001, respectively). In the Rhythmic Weight Shift test, the postoperative 3rd-month directional control (forward-backward) value (74.25 ± 11.51%) was statistically significantly higher compared to the preoperative directional control (forward-backward) value (67.76 ± 11.38%) (p = .011). The postoperative 3rd-month directional control (forward-backward) value (74.25 ± 11.51%) was statistically significantly higher compared to the postoperative 1st-month directional control (forward-backward) value (68.43 ± 14.00%) (p = .028). Conclusion: Surgical treatment resulted in an improvement in the maintenance of dynamic balance in children with strabismus.

The Impact of Weight Shifts on Inflation: Evidence for the Euro Area HICP

Shifts in household consumption feed into euro area inflation via the annual updating of product weights. The partial effect of weight changes on inflation is not quantified by statistical offices. We therefore propose a decomposition of the inflation rate, measured by the annual percentage change of the Harmonised Index of Consumer Prices (HICP), into the overall price change assuming weights at the previous year’s level and a weighting effect. We discuss this decomposition against a decomposition into pure price change and quantity effects. Our empirical results show that euro area inflation has been noticeably impacted by weighting effects since 2021. Before 2022, we observe a close relationship between weighting and quantity effects. As weighting effects can be calculated without delay from publicly available HICP data, we argue that this decomposition is relevant in terms of providing timely information for analysts and monetary policymakers.

Early Play Behaviors of Infants at Elevated Likelihood for Autism Spectrum Disorder.

Although research has examined early identification of autism spectrum disorder (ASD), few studies have found behavioral markers during midinfancy associated with later ASD diagnosis. To examine infants' play behaviors and atypical positions at age 6 mo and later outcome classification among infants at elevated likelihood (EL) and typical likelihood (TL) for ASD. Atypical positions refer to movement patterns indicative of motor delays or deviations, including atypical extension and flexion, poor weight shift and rotation, hypertonicity or hypotonicity, and the presence of primitive reflex patterns. Observational cohort longitudinal design using blinded video analysis. Fifty-eight infants (41 EL infants and 17 TL infants) 6 mo of age. Infants later diagnosed with ASD needed more support to engage in play at age 6 mo compared with infants who did not receive an ASD diagnosis (U = 130, z = -2.29, p < .05, r = .31). Atypical positions at 6 mo of age were not associated with a later diagnosis of ASD. Play behaviors may be early indicators of developmental differences for infants later diagnosed with ASD. The results of this pilot study suggest the need to observe the quality of interaction with a caregiver and objects during early play, which may serve as potential early indicators of ASD. Plain-Language Summary: Few studies have found behavioral markers during midinfancy that are associated with a later diagnosis of autism spectrum disorder (ASD). The results of this study showed that infants who were later diagnosed with ASD were found to have differences in play behaviors compared to infants who were not later diagnosed with ASD. Thus, early play behaviors may be an early indicator of developmental differences for infants who are later diagnosed with ASD.

Referent Control of Side-to-Side Body-Weight Transfer During Standing and Stepping in Adults

Research suggests that locomotion may be primarily caused by shifting stable body balance from one location in the environment to another with subsequent rhythmical muscle activation by the central pattern generator (CPG), constituting a multi-level control system. All levels interact with environmental forces affected by proprioceptive and vestibular reflexes as well as vision. A similar multi-level control schema is likely used to shift body balance laterally when the body weight is rhythmically transferred from side-to-side. In order to do so, the system shifts a specific body posture in space. This body posture is referred to as the threshold or referent body posture, R, at which all muscles involved can be at rest but are activated depending on the deflection of the actual body posture, Q, from R. This concept has previously been investigated for forward and backward locomotion. The purpose of the present study was to verify if it was also applicable to locomotor tasks in other directions such as sidestepping. We predicted that during sidestepping, the actual and referent posture can transiently match each other bringing the activity of multiple muscles to a minimum. The existence of such minima was demonstrated in healthy adults performing three locomotor tasks involving shifts of the body weight from side-to-side thus further supporting the validity of the multi-level control scheme of locomotion.

Formation of the calpain-1/calpastatin complex promotes activation of calpain-1 under oxidizing conditions.

Calpains are cysteine proteinases responsible for many biological roles in muscle, including protein degradation, muscle growth, and myoblast fusion. Calpains are inhibited by calpastatin, an endogenous inhibitor. Other factors, such as variations in pH, ionic strength, and oxidation influence calpain activity. This study aimed to determine the extent to which oxidation influences calpastatin inhibition of calpain-1. A series of order of addition assays were used to determine calpain-1 calcium activation and autolysis after exposure to an oxidizing agent (n-ethylmaleimide [NEM] or hydrogen peroxide [H2O2]. In the first series, purified calpastatin was added to the assay before or after oxidizing exposure at 165mM NaCl, pH 6.5. In the second series, incubation buffer ionic strength (165mM or 295mM NaCl) was evaluated. The inhibitory activities of purified porcine calpastatin, purified human calpastatin domain I, or a subdomain B inhibitor peptide were evaluated in the third series. In the fourth series, a maleimide-polyethylene glycol molecule (MAL-PEG; MW = 5,000 Dalton) was used to evaluate the accessibility of free sulfhydryl groups and tagging of calpain-1 under each condition through a molecular weight shift assay. Results from this study indicate that autolysis of calpain-1, when used as an indicator of activation, occurred when the calpain-1/calpastatin complex was exposed to an oxidant or cysteine modifier such as NEM. However, when calpain-1 was exposed to the cysteine modifier before calpastatin, autolysis of calpain-1 did not occur or was significantly decreased (P < 0.05). Irreversible modification of cysteine residues by NEM prevented activation of calpain-1 in the absence of calpastatin, but if the cysteine modification is potentially reversible (H2O2), calpain-1 activity can be recovered. Results from this study indicate that when calpastatin is bound to calpain-1, calpain-1 activation can occur even after being exposed to a cysteine modifier (NEM) or hydrogen peroxide (H2O2). Calpain-1 is not tagged with maleimide-polyethylene glycol (MAL-PEG) in the presence of calpastatin, indicating that calpastatin blocks or covers free cysteines on calpain-1 from modification. Moreover, exposure to calpain-1/calpastatin complex with a cysteine modifier allows activation of calpain-1, indicating that the inhibitory action of calpastatin is compromised. These results indicate a regulatory role for calpastatin that is not inhibitory but protective for calpain-1.

Intermittent Fasting Alters O2 Consumption and Body Composition in Young Rats: Comparative Analysis between Females and Males

Objectives: Intermittent Fasting (IF), time-restrictive food intake, has been shown to improve cognitive functions and reduce age-related behavioral impairments in rodent models. Our prior studies have found that IF intervention has significantly reduced body weights and food intake in male Fsher-344 rats; however, females did not display IF-induced declines in body weights and food intake. The exact mechanism for the sex differences in body weight and food intake during IF is not fully understood. Factors such as shifts in body composition and metabolic demand may contribute to variations in body weight shifts and food consumption. We hypothesized that changes in body composition and metabolic shifts may contribute to sex differences in body weight and food consumption in response to IF. Methods: Thirty-six, two-month-old male and female Fisher-344 rats were randomly assigned to four groups: ad libitum (AL) male, IF males, AL females, IF females. The AL group had 24/7 access to food and water while the IF group had 24/7 access to water and full access to food on an every-other-day basis for four weeks. After four weeks of IF intervention, rats were introduced to a metabolic rate (respiratory gas analyzer) and a grip strength test. In addition, body scans were performed using a Lunar Piximus rodent densitometer, (GE Lunar corporation). Group differences were analyzed with two-way ANOVA per Prism Graph Pad software. Following body scans, animals were euthanized, and tissues were sectioned, weighted, and stored for future analysis (brain, skeletal muscles, and adipose tissues). Results: IF intervention resulted in reduced body mass in males (vs. AL males, p&lt;0.0001) but not in females. Average daily food intake tended to be lowered in IF groups compared to their AL counterparts. Densitometry results revealed that the IF males had a decreased lean mass (vs. AL males, p&lt;0.0001) and fat mass (vs. AL males, p&lt;0.0001). Neither lean mass nor fat mass were changed in females as a result of IF. After two weeks of IF, O2 consumption was lowered in IF females compared to AL (P=0.0215 fed-state, P=0.0030 fast-state); however, no significant effect was seen in males. Grip strength was not significant among groups. Conclusions: In the present study, IF males significantly reduced body weights, as well as both fat and lean mass while females did not exhibit IF-induced changes. Interestingly, IF females displayed declines in oxygen consumption while males did not change. The decrease in oxygen consumption (slower metabolism) in IF females can be seen as a compensatory mechanism by the body to conserve energy and maintain body weights and composition shifts. The sexual dimorphic effect of body composition shifts is intriguing and the metabolic adaptations in skeletal muscle/fat tissues will be the focus of follow-up investigations. Funding source: P20GM113109 Cognitive and Neurobiological Approaches to Plasticity (CNAP) center. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Dynamic Single-Leg Balance Tests of Physiotherapy Students: A Comparison of Body-Active Weight Shift Test and Two Sudden Disturbance Tests

BACKGROUND: Balance is essential to maintain and stabilize the transition from static to dynamic posture. The human body can maintain the center of gravity within the base of support and to process input from vision, the vestibular apparatus, and the somatic senses. AIM: The research aimed to check the correlation of the active body-weight shift test (Y balance test [YBT]) and two sudden perturbation tests in physiotherapy students. METHODS: In a cross-sectional study, a descriptive research design was used. Twenty-nine healthy adults (14 men and 15 women) with a mean age of 23.6 ± 6.3 were tested using the active body-weight shift test and two sudden perturbation tests. A descriptive statistical analysis using correlation coefficients was performed. RESULTS: Our subjects’ average values of the test results meet the normative values. There is a correlation between the YBT test and the crossover hop test in the anterior (p &lt; 0.01), posterior-medial, and posterior-lateral directions (p &lt; 0.05), and the triple-hop test forward in the posterior-medial and posterior-lateral directions (p &lt; 0.05), and anterior direction (p &lt; 0.01) for the left extremity, except for the anterior direction to the right. With the right extremity, there is a correlation between the YBT test and the crossover hop test and triple-hop test forward in the posterior medial (p &lt; 0.05), the crossover hop test in the posterior medial and posterior lateral to the left (p &lt; 0.05), and the right (p &lt; 0.01), but no correlation in the anterior direction in either of them. CONCLUSION: The data of all physiotherapy students in our study meet the normative data, and no difference due to gender has been observed. There is a correlation between the active body-weight shift test and sudden perturbation tests with or without lateral movement for the left extremity, but not for the right extremity. We can assume better results when standing on an undominant limb, which can lead to insufficient support when standing on a dominant limb. What should not be the case in providing patient safety.

Characteristics and Consequences of Falls in People Who Use Wheelchairs in Long-Term Care Settings

ObjectivesThe purpose of this study was to understand the characteristics and consequences of falls in individuals using wheelchairs in long-term care settings. DesignObservational analysis of real-world falls in long-term care. Setting and ParticipantsResidents using wheelchairs from 2 long-term care facilities in British Columbia, Canada (n = 32 participants, mean age = 84.7 years, 12 women). MethodsTwo raters used the validated Falls Video Analysis Questionnaire, adapted from the original version, to assess the causal, behavioral, and environmental aspects of falls from wheelchairs. ResultsA total of 58 wheelchair fall videos were identified out of 300 total videos that were collected from 2007 to 2014. Wheelchair falls were most often caused by incorrect transfer or shift of body weight (70.7%). Participants most often fell backward with 89.7% striking their pelvis. Individuals using wheelchairs had limited protective response, with only 10.3% demonstrating a step response. Improper brake position contributed to 67.2% of falls. No serious fall-related injuries were reported. Conclusions and ImplicationsThe findings highlight the unique nature of falls in older adults who use wheelchairs in long-term care settings. Overall, the results of this study support clinical practice and the critical need for developing specialized fall prevention and fall detection interventions for individuals who use wheelchairs in long-term care.

From Pulp to Aromatic Products-Reaction Pathways of Lignin Depolymerization.

This study investigated the depolymerization of lignin into aromatic monomer compounds under hydrothermal conditions. A reaction scheme highlighting secondary alkylation reactions as well as the molecular weight shift was developed based on the experimental data. Lignin is produced in large quantities in paper production and dissolved in what is known as black liquor (BL). To avoid lignin recovery as an additional process step, BL is used directly as feedstock in the hydrothermal liquefaction (HTL) in this work. We performed various batch experiments in micro autoclaves with BL and model substances at different reaction temperatures (TR = 250-400 °C) and a holdingtime of tR = 20 min, as well as continuous experiments (TR = 325-375 °C, tR = 20 min). We were able to show that different derivatives of catechols are the main products among the monomers in our process. With the help of the model substance experiments, we were able to work out three main reactions: demethoxylation, demethylation, and alkylation. This behavior could be observed in the case of BL from hardwood as well as from softwood. 31P nuclear magnetic resonance (NMR) spectroscopy analysis has shown that these reactions take place on aromatic monomers as well as on larger aromatic oligomer structures. At higher temperatures, a large fraction of the carbon ends up in the solid product, while the yields of the monomers decrease sharply. 13C NMR spectroscopy of the solid material shows that the monomers are probably incorporated into the solid phase by repolymerization. We were also able to see this effect using size exclusion chromatography analysis based on the relative molecular weight. From all of the analytical results of the products, a reaction scheme was developed that describes the reaction pathways of the lignin during HTL. Based on this, a reaction kinetic model can be developed in the next step.

Regional differences in the biological variability of plantar pressure as a basis for refining diagnostic gait analysis.

The variability of movement plays a crucial role in shaping individual's gait pattern and could, therefore, potentially serve diagnostic purposes. Nevertheless, existing concepts for the use of variability in diagnosing gait present a challenge due to the lack of adequate benchmarks and methods for comparison. We assessed the individuality of contribution of foot parts that directly mediate the transmission of forces between the foot and the ground in body weight shifting during walking based on 200 pedobarometric measurements corresponding to the analysed foot parts for each of 19 individuals in a homogeneous study group. Our results show a degree of individualisation of the contribution of particular foot parts in the weight-shift high enough to justify the need to consider it in the diagnostic analysis. Furthermore they reveal noticeable, functionally driven differences between plantar areas most apparent between the lowest individuality for the first foot ray and the highest for second one and metatarsus. The diagnostic reference standard in pedobarometry should describe the contribution in the shift of body weight during walking for each area of the foot separately and include information on the intra-individual variation and individualisation of descriptors of the contribution. Such a comprehensive standard has the potential to increase the diagnostic value of pedobarometry through enrichment of the assessment description.