Spatial Modification Research Articles

Study on potential antigenicity and functional properties of whey protein treated by high hydrostatic pressure based on structural analysis

High hydrostatic pressure (HHP) is extensively utilized in the field of food processing due to its remarkable ability to preserve the freshness of food. The potential antigenicity of β-lactoglobulin (β-LG) in whey protein isolate (WPI, 3%) treated by HHP was detected by enzyme linked immunosorbent assay (ELISA) using monoclonal antibodies. Furthermore, the impact of pressure-induced structural alterations on the emulsification properties and antioxidant activity of WPI was investigated. The findings revealed that pressures exceeding 300 MPa resulted in molecular aggregation, the formation of inter-molecular disulfide bonds, and an increase in surface hydrophobicity (H0). The percentage of β-sheet decreased along with the pressure. The results showed the increment of α-helix and β-turn with pressure. ELISA demonstrated a significant reduction in the antigenicity of β-LG following HHP treatment (100–600 MPa), with a slight recovery observed at 300 MPa. These spatial structural modifications led to the unfolding of the β-LG molecule, thereby enhancing its digestibility. Moreover, HHP treatment substantially improved the antioxidant properties, with the exposure to hydrophobic amino acids contributing to increased antioxidant properties and emulsion stability.

Comparison of the effects of amitriptyline, melipramine and fluoxetine on acquisition and spatial alteration of avoidance responses in rats

The effects of amitriptyline (10 mg/kg), melipramine (10 mg/kg), and fluoxetine (5 mg/kg) on the acquisition of conditioned active avoidance responses and their spatial alteration in rats were studied. During the acquisition of avoidance, a passage in the partition was open, adjacent to the rear wall of the shuttle chamber. On the 5th experimental day after the end of the training, this distal opening was closed and the proximal one was opened, after which avoidance performance under changed conditions was tested for 20 trials. Melipramine and amitriptyline accelerated the acquisition of avoidance responses. Changing the location of the opening disrupted the learned skill, especially in the control animals. Melipramine and fluoxetine statistically significantly (in contrast to amitriptyline) accelerated the recovery of the level of avoidance. The positive effect of melipramine and fluoxetine is explained by a psychostimulating component in their spectrum. The inability of amitriptyline to produce a significant effect in this model is due to its psychosedative properties. The data obtained allow us to conclude that the acquisition of the active conditioned avoidance responses and their spatial modification can be used to analyze the antidepressant activity of pharmacological agents.

Spatiotemporal Dynamics of Ecosystem Services Driven by Human Modification over the Past Seven Decades: A Case Study of Sihu Agricultural Watershed, China

Understanding the effects of human modification on ecosystem services is critical for effectively managing multiple services and achieving long-term sustainability. The historical dynamics of ecosystem services are important for detecting the impacts before and after intensive modification and deserve further study. To this end, we quantified the spatiotemporal dynamics of 11 ecosystem services across the Sihu agricultural watershed in 1954, 1983, 2001, and 2018. We used the Spearman coefficient, self-organized maps clustering, and redundancy analysis to explore the spatial patterns and potential modification drivers of temporal variations of ecosystem service provision. The results revealed the following: (1) The spatial correlations among ecosystem services in a single year were inconsistent with the ecosystem service change associations during two-time steps. The snapshot correlations at one time led to misunderstandings (such as water yield and runoff control or soil carbon sequestration, and habitat quality changed direction from synergy to trade-off) and missed synergies (such as water purification and recreational potential); (2) Most ecosystem services could be synergetic in one bundle with multifunctionality before intensive modification, but later transformed to single or limited services dominated bundles, especially in lake-polder areas; (3) Lake reclamation and hydraulic infrastructure were the most significant modification indicators explaining the variation of ecosystem services (30.9% of variance explained by lake reclamation in 1954, 38.2% of variance explained by hydraulic infrastructure in 2018). Meanwhile, changes in dominant drivers also indicated the transition from lake-based ecosystem service supply to engineered service. An improved understanding of the spatiotemporal pattern of ecosystem services and the underlying human modification influence is vital for realizing the sustainability and multifunctionality of agricultural watershed.

Motor and cognitive deficits limit the ability to flexibly modulate spatiotemporal gait features in older adults with mild cognitive impairment.

Introduction: Dance-based therapies are an emerging form of movement therapy aiming to improve motor and cognitive function in older adults with mild cognitive impairments (MCIs). Despite the promising effects of dance-based therapies on function, it remains unclear how age-related declines in motor and cognitive function affect movement capacity and influence which movements and rhythms maximize dance therapy efficacy. Here, we evaluated the effects of age and MCI on the ability to accurately modulate spatial (i.e., joint kinematics), temporal (i.e., step timing), and spatiotemporal features of gait to achieve spatial and temporal targets during walking. Methods: We developed novel rhythmic movement sequences-nine spatial, nine temporal, and four spatiotemporal-that deviated from typical spatial and temporal features of walking. Healthy young adults (HYA), healthy older adults (HOA), and adults with MCI were trained on each gait modification before performing the modification overground, with kinematic data recorded using wearable sensors. Results: HOA performed spatial (p = 0.010) and spatiotemporal (p = 0.048) gait modifications less accurately than HYA. Individuals with MCI performed spatiotemporal gait modifications less accurately than HOA (p = 0.017). Spatial modifications to the swing phase of gait (p = 0.006, Cohen's d = -1.3), and four- and six-step Duple rhythms during temporal modifications (p ≤ 0.030, Cohen's d ≤ 0.9) elicited the largest differences in gait performance in HYA vs. HOA and HOA vs. MCI, respectively. Discussion: These findings suggest that age-related declines in strength and balance reduce the ability to accurately modulate spatial gait features, while declines in working memory in individuals with MCI may reduce the ability to perform longer temporal gait modification sequences. Differences in rhythmic movement sequence performance highlight motor and cognitive factors potentially underlying deficits in gait modulation capacity, which may guide therapy personalization and provide more sensitive indices to track intervention efficacy.

Spatial pH variability of coral reef flats of Kiritimati Island, Kiribati

Ocean acidification poses a threat to carbonate-dominated marine systems, such as tropical coral reefs, as it impacts the ability of organisms to calcify. For assessing the susceptibility of coral reef flats to open ocean acidification it is crucial to better understand the dynamics between the carbonate chemistry of open ocean waters flowing onto coral reef flats and the ecological and hydrodynamic processes that locally modify seawater conditions.In this study, variations in seawater pH and temperature were measured along cross-reef flat transects in high resolution (∼0.3 m) and complemented by surveys of the benthic community composition and reef flat bathymetry.Results represent a snapshot in time and suggest that reef flat hydrodynamic processes determine spatial pH modifications, with little influence of variations in benthic community composition. As mean reef flat pH largely equals ocean conditions, ocean acidification has had and will have an unhampered impact on narrow fringing reef flats.

Circumferential spatial tooth profile modification of flexspline for strain wave gear (A novel method and a case study)

Circumferential spatial tooth profile modification of flexspline for strain wave gear (A novel method and a case study)

Leveraging discrete event simulation modeling to evaluate design and process improvements of an emergency department

This study exemplifies the practical application of the Discrete Event Simulation (DES) approach for evaluating the effectiveness of suggested processes and design modifications in improving the existing bottlenecks of an Emergency Department. EDs are under escalating pressure to deliver efficient care while handling considerable challenges, such as overcrowding, delays, length of stay, safety risks, or staffing. Many ED appointments are non-urgent and can be treated in an alternative outpatient setting. Suitable demand-capacity matching and adjusted admission protocols reduce ED patients' Length of Stay (LOS) and improve boarding times. Alternatively, new design suggestions include applying results-pending areas where lower acuity patients wait for their pending lab or imaging results. In this study, DES assesses underlying conditions and existing bottlenecks in an existing ED. The current ED flow involved a "pull-until-full" for exam room boarding and bedside registration after triage fulfillment. Nonetheless, the ED experienced boarding delays for patients waiting to be admitted into the hospital. This study explored two scenarios in DES as potential alternatives for reducing LOS: the implication of a "rapid-admit" protocol and a "results-pending" area. Findings showed that the Rapid-Admit process reduced the admitted patient's LOS by 16%. On average, the results-pending implication reduced the admit LOS by an average of 32% across all ESI levels. These findings suggest the importance of process, staffing, and spatial modifications to achieve ED operational improvements. DES enabled a data-driven approach to evaluate bottlenecks, enhance architect-owner communication, and optimize the system for future design and process improvement alternatives.

Binaural detection thresholds and audio quality of speech and music signals in complex acoustic environments.

Every-day acoustical environments are often complex, typically comprising one attended target sound in the presence of interfering sounds (e.g., disturbing conversations) and reverberation. Here we assessed binaural detection thresholds and (supra-threshold) binaural audio quality ratings of four distortions types: spectral ripples, non-linear saturation, intensity and spatial modifications applied to speech, guitar, and noise targets in such complex acoustic environments (CAEs). The target and (up to) two masker sounds were either co-located as if contained in a common audio stream, or were spatially separated as if originating from different sound sources. The amount of reverberation was systematically varied. Masker and reverberation had a significant effect on the distortion-detection thresholds of speech signals. Quality ratings were affected by reverberation, whereas the effect of maskers depended on the distortion. The results suggest that detection thresholds and quality ratings for distorted speech in anechoic conditions are also valid for rooms with mild reverberation, but not for moderate reverberation. Furthermore, for spectral ripples, a significant relationship between the listeners' individual detection thresholds and quality ratings was found. The current results provide baseline data for detection thresholds and audio quality ratings of different distortions of a target sound in CAEs, supporting the future development of binaural auditory models.

A Numerical Investigation on Hydrothermal Performance of Micro Channel Heat Sink with Periodic Spatial Modification on Sidewalls.

Electronic gadgets have been designed to incorporating very small components such as microcontrollers, electronic chips, transistors, microprocessors, etc. These components are exceptionally heat sensitive and can be wrecked if heat is not released. As a result, the thermal control of such components is critical to their optimum performance and extended life. The use of a microchannel heat sink (MCHS) has shown promising solutions to remove the excess heat. In this paper, we have proposed a novel design of MCHS and investigated it numerically. Four different surface modifications on the sidewall of the passage, namely, extended triangular surface (ETS), extended circular surface (ECS), triangular groove surface (TGS), and the circular groove surface (CGS) in the passage of the microchannel have been exploited in the Reynolds number of 100-900. In the presence of geometrical modification, the cooling capacities have been enhanced. The results show that the Nusselt numbers of ETS-MCHS, ECS-MCHS, TGS-MCHS, and CGS-MCHS are increased by 4.30, 3.61, 1.62, and 1.41 times in comparison to the Nusselt number of MCHS with smooth passage, while the friction factor values are increased by 7.33, 6.03, 2.74, and 1.68 times, respectively. In addition, the thermohydraulic performance parameter (THPP) has been evaluated and discussed. The fact that MCHS have THPP values greater than unity demonstrates that the passage's geometries are a practical means of achieving effective thermal management.

The spatial modification effect of predictors on household level food insecurity in Ethiopia

Household food insecurity remains highly prevalent in developing countries (including in Ethiopia) and it has been recognized as a serious public health problem. Several factors such as demographic, economic, social, and clinical factors influence household food insecurity, and these vary geographically. In this work, we investigate the geographical modification of the effect of several factors on chronic food insecurity. The data is from the Ethiopia socioeconomic survey conducted by the Ethiopia Central Statistics Agency (ECSA) in collaboration with the World Bank. Ethiopia socioeconomic survey is a long-term project to collect nationally representative panel survey of over 6500 households. A geo-additive model which accounts the structured and unstructured special effect was adopted to estimate household food insecurity risk factors. The study also revealed significant spatial variations on household food insecurity among administrative zones. Mainly, household living in the Sidama, Gamo Gofa, Shinille, Basketo, Wolyita, Wag Hemira, Liben, Awi, Eastern Tigray and West Harerghe zones, having higher food insecurity than the other zones in Ethiopia. Moreover, the analysis also showed that availability of credit services, proximity to service centers, average years of schooling of members of the household, and household assets are negatively associated with household food insecurity, whereas shocks, age, and dependency ratio increase the odds of a household to be food insecured. The generalized geo-additive mixed-effects model enables simultaneous modeling of spatial correlation, heterogeneity and possible nonlinear effects of covariates. Our study investigated the spatial heterogeneity of household level food insecurity, and its association with shocks, age, dependency ratio, availability of credit services, average years of schooling, and household assets. Our findings have also an important implication for planning as well as in the search for the variables that might account for the residual spatial patterns.

Time-resolved 2D angular scattering of soot particles in atmospheric turbulent flames

A better understanding of the formation of soot particles is essential to improve combustion-related processes. For this purpose, this work reports for the first time the measurement of the size of soot particles under formation in a turbulent atmospheric flame in a planar configuration. This is ensured by the detection of the elastic scattering of a laser sheet thanks to two cameras positioned at different scattering angles (45° and 135°). The size information is then used to interpret the scattering signal collected by an additional camera positioned at 90° in order to evaluate the soot number concentration. This last step relies on a calibration ensured by soot volume fraction and primary particle size previously determined by autocompensating laser-induced incandescence in the same flame. Moreover, the use of a 1 kHz repetition rate nanosecond laser and three high speed CMOS cameras enables the access to these physical parameters with a high temporal resolution. The 2D and time-resolved soot characterization is of interest because it enables the observation of the temporal and spatial modifications of soot structures when propagating in such turbulent flames. In particular, in this flame, the transport and mixing of soot pockets are clearly observed and the impact of these processes on the size and number concentration is quantified.

The Spatial Modification of the Non-Linear Effects of Ambient Oxides of Nitrogen during Pregnancy on Birthweight in a South African Birth Cohort

Background Birthweight is strongly associated with infant mortality and is a major determinant of infant survival. Several factors such as maternal, environmental, clinical, and social factors influence birthweight, and these vary geographically, including across low, middle, and economically advanced countries. The aim of the study was to investigate the geographical modification of the effect of oxides of nitrogen exposure on birthweight adjusted for clinical and socio-demographic factors. Methods Data for the study was obtained from the Mother and Child in the Environment birth cohort study in Durban, South Africa. Pregnant females were selected from public sector antenatal clinics in low socioeconomic neighborhoods. Land use regression models were used to determine household level antenatal exposure to oxides of nitrogen (NOx). Newborns were assessed at the local hospitals by doctors or qualified midwives. Six hundred and seventy seven births were analysed, using the geoadditive model with Gaussian distribution and identity link function. Continuous covariates were modelled by thin-plate regression splines and smoothing was estimated by the generalized cross validation. Findings A total of 677 births were analyzed. The newborns in the cohort had mean birthweight of 3106·5g (standard deviation (SD):538·2g and maternal mean age was 26 years (SD: 5·7). The mean prenatal exposure to NOx was found 31·5µg/m3 with standard deviation of 8·6 µg/m3. A spatially modified NOx exposure-related effect on birthweight was found across two geographic regions in Durban. Prenatal exposure to NOx was also found to have a non-linear effect on the birthweight of infants. The geoadditive model adjusted for maternal age, weight gain, and body mass index showed significant non-linear influences. Conclusion The study suggested that incorporating spatial variability is important to understand and design appropriate policies to reduce air pollution in order to prevent risks associated with birthweight and child development.

Beam spatial intensity modification based on stimulated Brillouin amplification.

The beam spatial intensity distribution is critical to laser applications both in the scientific and the industrial fields. Here, a method for beam spatial intensity modification based on stimulated Brillouin amplification (SBA) is proposed, which provides an alternative approach of laser beam shaping accompanied by efficient energy amplification. Three beam shaping schemes based on SBA has been demonstrated and evaluated in theoretical simulation and experiments with pulsed laser. The results indicate that the spatial distribution can be modified by manipulation of the beam polarization and the intensity. Finally, the shaped Stokes beam has been modified into the flat-top distribution with the output pulse energy increasing to 4.43 times of the input energy, proving the feasibility of SBA spatial shaping method.

GNSS receiver for Q-Sat and its analysis of precise orbit determination

The Earth's gravity field and upper atmosphere are very important scientific information and their mechanical models can be obtained by inversion of the satellite precision orbit. It would be ideal to develop a constellation of satellites distributed with different orbits to measure atmospheric drag and gravity. Based on this idea, Tsinghua University developed a microsatellite Q-Sat for measuring the gravity field and the density of the upper atmosphere. Low-cost, high-precision measurements can greatly improve the cost effectiveness of scientific missions. In this paper, a spatial modification method for GNSS receivers based on commercial off-the-shelf was proposed. The base module of the receiver is a ground-based general-purpose device, and this modification method allows for the space-batch modification of industrial-grade devices. The modified receiver was successfully applied to the Q-Sat and a large amount of continuous on-orbit data were obtained. Data analysis results show that the receiver can simultaneously receive GPS-L1\\L2 and BD1\\BD2 multifrequency navigation satellite signals in the highly dynamic spatial environment. To reduce the precision orbit determination error, the GNSS observations were corrected by antenna center modelling, and the long-term orbit determination accuracy is stabilized at the centimeter level. The commercial off-the-shelf based GNSS receiver modification method and precision orbit determination strategy can provide a reference for low-cost and high-precision microsatellites.

A Spatial Adaptation Strategy for Safe Campus Open Spaces during the COVID-19 Pandemic: The Case of Korea University.

Open spaces on campus offer various opportunities for students. However, the coronavirus disease (COVID-19) pandemic has affected students’ comfort when occupying open spaces on campus. The purpose of this study is to investigate possible spatial adaptation strategies for safe campus open spaces during the COVID-19 pandemic. For this research, a case study was conducted using a mixed methodology with behavioral mapping that investigated students’ perceptions at Korea University, Seoul, Korea. A qualitative approach was first conducted with behavioral mapping; the results show that despite some behavioral and spatial changes, people still occupy open spaces on campus for various meaningful activities. A quantitative approach with structural equation modeling (SEM) was also conducted to understand the required spatial modifications to improve the safety of open spaces on campus. The positive correlation between (i) social distancing measures, (ii) health protocols, and (iii) accessibility and occupational comfort with (iv) individuals’ fear of COVID-19 as a positive moderation are the four hypotheses proposed in this study. The results suggest that social distancing measures have no correlation with occupational comfort, while accessibility has the largest positive correlation. Suggestions are presented for providing accessible and equally distributed open spaces on campus to avoid overcrowding. Spatial health protocols are also found to positively correlate with occupational comfort, and the perception of the severity of COVID-19 strengthens this correlation. Tangible physical measures to prevent the spread of the virus are necessary to improve students’ sense of comfort and safety in open spaces on campus.

Spatio-Temporal Modification of Lignin Biosynthesis in Plants: A Promising Strategy for Lignocellulose Improvement and Lignin Valorization.

Lignin is essential for plant growth, structural integrity, biotic/abiotic stress resistance, and water transport. Besides, lignin constitutes 10–30% of lignocellulosic biomass and is difficult to utilize for biofuel production. Over the past few decades, extensive research has uncovered numerous metabolic pathways and genes involved in lignin biosynthesis, several of which have been highlighted as the primary targets for genetic manipulation. However, direct manipulation of lignin biosynthesis is often associated with unexpected abnormalities in plant growth and development for unknown causes, thus limiting the usefulness of genetic engineering for biomass production and utilization. Recent advances in understanding the complex regulatory mechanisms of lignin biosynthesis have revealed new avenues for spatial and temporal modification of lignin in lignocellulosic plants that avoid growth abnormalities. This review explores recent work on utilizing specific transcriptional regulators to modify lignin biosynthesis at both tissue and cellular levels, focusing on using specific promoters paired with functional or regulatory genes to precisely control lignin synthesis and achieve biomass production with desired properties. Further advances in designing more appropriate promoters and other regulators will increase our capacity to modulate lignin content and structure in plants, thus setting the stage for high-value utilization of lignin in the future.

Tuning carrier density and phase transitions in oxide semiconductors using focused ion beams

Abstract We demonstrate spatial modification of the optical properties of thin-film metal oxides, zinc oxide (ZnO) and vanadium dioxide (VO2) as representatives, using a commercial focused ion beam (FIB) system. Using a Ga+ FIB and thermal annealing, we demonstrated variable doping of a wide-bandgap semiconductor, ZnO, achieving carrier concentrations from 1018 cm−3 to 1020 cm−3. Using the same FIB without subsequent thermal annealing, we defect-engineered a correlated semiconductor, VO2, locally modifying its insulator-to-metal transition (IMT) temperature by up to ∼25 °C. Such area-selective modification of metal oxides by direct writing using a FIB provides a simple, mask-less route to the fabrication of optical structures, especially when multiple or continuous levels of doping or defect density are required.

Energy poverty: The paradox between low income and increasing household energy consumption in Brazil

Energy consumption can put a heavy burden on the family budget of the low-income population; many families cannot afford enough energy for their subsistence, comfort and leisure. The aim of this research was to understand the behavioral factors of a vulnerable population associated with their energy consumption. The research relates actual energy consumption data to spatial modifications of social households, to indoor thermal conditions, and to residents' behavior. The results showed that energy consumption has increased over the years. The main factors associated with the amount of energy used are: expansion of the built area, number of occupants, quantity of equipment (state of use and energy efficiency), time of the year (summer), and family composition. Of the sample, 51.0% consumed over 100.0 kWh per month (latest figure from August 2021) and enjoyed the minimum 10.0% discount of the National Social Tariff, while only 4.7% enjoyed the maximum discount of 65.0%; it seems that fully enjoying the subsidy offered by the government is unattainable for the low-income population. It is noteworthy that 37.6% of the sample is highly vulnerable and yet consume as much energy as households in a situation of energy security.

Using spatial neighborhoods for parameter adaptation: An improved success history based differential evolution

Differential Evolution (DE) has been widely appraised as a simple yet robust population-based, non-convex optimization algorithm primarily designed for continuous optimization. Two important control parameters of DE are the scale factor F, which controls the amplitude of a perturbation step on the current solutions and the crossover rate Cr, which limits the mixing of components of the parent and the mutant individuals during recombination. We propose a very simple, yet effective, nearest spatial neighborhood-based modification to the adaptation process of the aforesaid parameters in the Success-History based adaptive DE (SHADE) algorithm. SHADE uses a historical archive of the successful F and Cr values to update these parameters and stands out as a very competitive DE variant of current interest. Our proposed modifications can be extended to any SHADE-based DE algorithm like L-SHADE (SHADE with linear population size reduction), jSO (L-SHADE with modified mutation) etc. The enhanced performance of the modified SHADE algorithm is showcased on the IEEE CEC (Congress on Evolutionary Computation) 2013, 2014, 2015, and 2017 benchmark suites by comparing against the DE-based winners of the corresponding competitions. Furthermore, the effectiveness of the proposed neighborhood-based parameter adaptation strategy is demonstrated by using the real-life problems from the IEEE CEC 2011 competition on testing evolutionary algorithms on real-world numerical optimization problems.

Privacy as a motivating factor for spatial layout transformation in Jordanian public housing

Various studies have addressed the issue of privacy and referred to its critical role in shaping the spatial organization and functional configurations of buildings. Residents of public housing projects tend to modify their homes to achieve different functional and occupancy objectives. While the variables that motivate tenants to alter their spatial layouts have been extensively studied, only a few studies have researched the role of privacy as a motivating factor in modifying public housing units upon extended periods of occupancy. Therefore, this study examines the role of privacy as a motivating factor in the spatial layout modification of public housing units in Jordan. It sampled a Jordanian public housing project in which the spatial layout of several housing units has been modified by residents over time. The spatial configuration of the original and the modified version of the housing unit was assessed in terms of visibility, accessibility, hierarchical structure, and the spatial organization of interior spaces. Additionally, face-to-face interviews were conducted with the residents to gain a better understanding of privacy considerations in modified units. The study of Jordanian public housing units revealed that residents carried out various modifications over time that encompassed enclosing balconies with interior living spaces, adding private entrances, or expanding the space of balconies and terraces. The Visibility Graph Analysis (VGA) and J-Graph analyses showed that home modifications precipitated hierarchical spatial relationships that echo established sociocultural traditions in Jordanian society. The data analysis emphasized the key role that privacy plays as a motivational factor for spatial layout transformation. Hence, this research underlines the imperative of integrating sociocultural needs with functional aspects in the process of designing public housing projects. Designers should embed higher levels of flexibility in their masterplans and home layouts. With residents' satisfaction and spatial flexibility in mind, designers should identify and engage concerned stakeholders during the initial stages of planning and design of public housing.