Moderate Flow Research Articles

Lack of pollinators selects for increased selfing, restricted gene flow and resource allocation in the rare Mediterranean sage Salvia brachyodon

Range contraction and habitat fragmentation can cause biodiversity loss by creating conditions that directly or indirectly affect the survival of plant populations. Fragmented habitats can alter pollinator guilds and impact their behavior, which may result in pollen/pollinator limitation and selection for increased selfing as a mechanism for reproductive assurance. We used Salvia brachyodon, a narrowly distributed and endangered sage from eastern Adriatic, to test the consequences of range contraction and habitat fragmentation. Molecular data indicate a severe and relatively recent species range reduction. While one population is reproductively almost completely isolated, moderate gene flow has been detected between the remaining two populations. The high pollen-to-ovule ratio and the results of controlled hand pollination indicate that S. brachyodon has a mixed mating system. Quantitative and qualitative differences in the community and behaviour of flower visitors resulted in limited pollination services in one population where no effective pollinator other than pollen and nectar robbers were observed. In this population, self-pollination predominated over cross-pollination. Various environmental factors, in which plant-pollinator interactions play a pivotal role, have likely created selection pressures that have led to genetic and phenotypic differentiation and different resource allocation strategies among populations.

The Effect of Material Flow Cost Accounting on Company Sustainability: Moderating Role of Green Accounting in Consumer Goods Industry Companies

This study analyzes the influence of material flow cost accounting in improving company sustainability. Material flow cost accounting. This research uses proxies for production costs, factory area, and output or production value. The population used in this research is all goods and consumption companies listed on the IDX for the 2015-2021 period. Through Purposive sampling, the samples obtained were 6 companies in that period, so 42 data were obtained. Data processing in this research was carried out using multiple regressions and moderated regression methods with an absolute difference value approach. This research concludes that MFCA (production costs) negatively and significantly affects company sustainability. This means that reducing production costs to get higher profits will increase the company's sustainability. Meanwhile, MFCA (factory area and output or production value) positively and significantly influences company sustainability. This shows that the wider the company's area and every time there is an increase in production results, the company's sustainability can increase. Besides, green accounting cannot moderate material flow cost accounting on company sustainability.

The mismatch between swimming speeds and flow regimes when optimising exercise regimes to improve Chinook salmon, Oncorhynchus tshawytscha, performance

Exercise regimes provide a promising opportunity to enhance production performance during hatchery rearing, but exercise-enhanced traits are presently poorly understood in Chinook salmon. In addition, spinal health can be a concern in some farms in New Zealand and unfavourable correlations between higher condition factor and spinal curvature have been detected. Exercise regimes, in other salmonids, have improved bone mineralisation and lowered condition factor. Therefore, we hypothesise that sustained swimming could be used as a tool to improve spinal health. Here we tested the influence of low (0.3 bl s−1) and moderate (0.8 bl s−1) flow regimes on post-smolt (initial size: wet weight = 82.9 ± 0.3 g, fork length = 174.6 ± 0.2 mm) Chinook salmon feed efficiency and growth performance, as well as spinal health. We first measured the actual swimming speeds of Chinook salmon under low and moderate flow regimes to determine differences in exercise levels. Swimming speeds were not different between the flow regimes and were much higher than the set flow, because the Chinook salmon were advancing around the tank, swimming faster than the set flow at their own chosen swimming speed. Moderate flow regimes improved feed efficiency but did not influence other feed and growth metrics or spinal curvature and vertebral anomalies prevalence or severity. Production performance significantly differed between individuals with normal spinal health and those that developed spinal anomalies (vertebral compression, −fusion, and/or -vertical shift) or spinal curvature (lordosis, kyphosis, and/or scoliosis). Chinook salmon that developed spinal anomalies were smaller, grew slower, and exhibited poorer feed efficiency, whereas individuals that developed spinal curvature were significantly heavier, longer, and had higher condition factor. The probability of individuals developing spinal curvature increased with higher condition factor. These results provide critical information for industry to consider in their selective breeding objectives to curb the prevalence and severity of spinal curvature incidences.

Quantitative Assessment of Hemodynamics Associated With Embolization Degree in Brain Arteriovenous Malformations.

Grading systems, including the novel brain arteriovenous malformation endovascular grading scale (NBAVMES) and arteriovenous malformation embocure score (AVMES), predict embolization outcomes based on arteriovenous malformation (AVM) morphological features. The influence of hemodynamics on embolization outcomes remains unexplored. In this study, we investigated the relationship between hemodynamics and embolization outcomes. We conducted a retrospective study of 99 consecutive patients who underwent transarterial embolization at our institution between 2012 and 2018. Hemodynamic features of AVMs were derived from pre-embolization digital subtraction angiography sequences using quantitative digital subtraction angiography. Multivariate logistic regression analysis was performed to determine the significant factors associated with embolization outcomes. Complete embolization (CE) was achieved in 17 (17.2%) patients, and near-complete embolization was achieved in 18 (18.2%) patients. A slower transnidal relative velocity (TRV, odds ratio [OR] = 0.71, P = .002) was significantly associated with CE. Moreover, higher stasis index of the drainage vein (OR = 16.53, P = .023), shorter transnidal time (OR = 0.15, P = .013), and slower TRV (OR = 0.9, P = .049) were significantly associated with complete or near-complete embolization (C/nCE). The area under the receiver operating characteristic curve for predicting CE was 0.87 for TRV, 0.72 for NBAVMES scores (ρ = 0.287, P = .004), and 0.76 for AVMES scores. The area under the receiver operating characteristic curve for predicting C/nCE was 0.77 for TRV, 0.61 for NBAVMES scores, and 0.75 for AVMES scores. Significant Spearman correlation was observed between TRV and NBAVMES scores and AVMES scores (ρ = 0.512, P < .001). Preoperative hemodynamic factors have the potential to predict the outcomes of AVM embolization. A higher stasis index of the drainage vein, slower TRV, and shorter transnidal time may indicate a moderate blood flow status or favorable AVM characteristics that can potentially facilitate embolization.

Enhancing Mechanical Performance of High-Lignin-Filled Polypropylene via Reactive Extrusion.

Polypropylene (PP) is one of the most extensively used commodity plastics. In terms of eco-friendliness, it is worth considering preparing high-lignin-filled PP. This study explores the incorporation of high lignin content, derived from acetic acid lignin (AAL) and Kraft lignin (KL), into PP through twin-screw extrusion and injection molding. The challenge lies in maintaining mechanical performance. A compatibilizer-specifically, maleic anhydride-grafted polypropylene (MAPP)-is employed to enhance lignin-PP compatibility by chemically bonding with lignin and physically associating with the PP phase. Results indicate that KL maintains better dispersity than AAL. Compatibilizers with a high maleic anhydride (MA) level (≥0.8 wt.%) and moderate melt flow index (MFI) in the range of 60-100 g 10 min⁻¹ prove favorable in constructing a reinforced PP/KL network. Optimizing with 40 wt.% lignin content and 10 parts per hundred (pph) of compatibilizer yields blends with mechanical performance comparable to neat PP, exhibiting a notable increase in modulus and heat deflection temperature (HDT). Furthermore, utilizing PP/lignin blends can lead to a 20% reduction in expenses and approximately 40% reduction in PP-induced greenhouse gas (GHG) emissions. This approach not only reduces PP costs but also adds value to lignin utilization in a sustainable and cost-effective manner.

Abstract WP195: The Impact of Tortuosity on Microwire Torquability

Introduction: Navigation of a microguidewire through the intracranial vasculature is crucial for the success and safety of neuroendovascular procedures. Its navigation is influenced by a combination of patient factors, such as vessel tortuosity, and device factors, such as microwire torquability. In this study, we compared the torquability of microwires in two vascular models of differing tortuosity. Methods: We tested torquability of three 0.014” nitinol microwires (Synchro Select Soft, Standard, or Support, Stryker Neurovascular, Fremont, CA) docked in either a moderate tortuosity silicone flow model of the middle cerebral artery (MCA), or a severe tortuosity model of the anterior cerebral artery (ACA). Tortuosity was determined by measuring the length of the centerline/straight length (MCA 1.28, ACA 2.22). The microwires were rotated proximally at a constant rate of 180 degrees per second, seven times clockwise and seven times counterclockwise. Rotation at the distal tip was quantified by measuring the change in angle every 0.2 seconds over 6 seconds. To quantify the deviation of distal tip motion from the ideal, the difference between the distal degrees measured and the proximal degrees rotated were summed and compared between wires. Results: In the severe tortuosity ACA model, the distal tip of the stiffer Support wire displayed significantly larger deviation from ideal than either the Standard (p&lt;0.0001) or Soft (p&lt;0.0001) wires. There was no significant difference amongst the three wires in the moderate tortuosity MCA model (p=0.598). Discussion: Our results demonstrated that increased vessel tortuosity decreased the torquability of the stiffer Support microwire. This was observed as “whip” motions of the Support wire in the severe tortuosity model, likely due to its higher bending rigidity. In cases of distal vessel selection or tortuous vasculature, our results suggest a Soft or Standard microwire should be utilized in place of a stiff wire.

Flutter limitation of drag reduction by elastic reconfiguration

Through experiments, we idealize a plant leaf as a flexible, thin, rectangular plate clamped at the midpoint and positioned perpendicular to an airflow. Flexibility of the structure is considered as an advantage at moderate flow speed because it allows drag reduction by elastic reconfiguration, but it can also be at the origin of several flow-induced vibration phenomena at higher flow speeds. A wind tunnel campaign is conducted to identify the limitation to elastic reconfiguration that dynamic instability imposes. Here, we show by increasing the flow speed that the flexibility permits a considerable drag reduction by reconfiguration, compared to the rigid case. However, beyond the stability limit, vibrations occur and limit the reconfiguration. This limit is represented by two dimensionless numbers: the mass number and the Cauchy number. Our results reveal the existence of a critical Cauchy number below which static reconfiguration with drag reduction is possible and above which a dynamic instability with important fluctuating loads is present. The critical dimensionless velocity is dependent on the mass number. Flexibility is related to the critical reduced velocity and allows defining an optimal flexibility for the structure that leads to a drag reduction by reconfiguration while avoiding dynamic instability. Furthermore, experiments show that our flexible structure can exhibit two vibration modes: symmetric and anti-symmetric, depending on its mass number. Because the system we consider is bluff yet aligned with the flow, it is unclear whether the vibrations are due to a flutter instability or vortex-induced vibration or a combination of both phenomena.

Jumping and leaping estimations using optic flow

Optic flow provides information on movement direction and speed during locomotion. Changing the relationship between optic flow and walking speed via training has been shown to influence subsequent distance and hill steepness estimations. Previous research has shown that experience with slow optic flow at a given walking speed was associated with increased effort and distance overestimation in comparison to experiencing with fast optic flow at the same walking speed. Here, we investigated whether exposure to different optic flow speeds relative to gait influences perceptions of leaping and jumping ability. Participants estimated their maximum leaping and jumping ability after exposure to either fast or moderate optic flow at the same walking speed. Those calibrated to fast optic flow estimated farther leaping and jumping abilities than those calibrated to moderate optic flow. Findings suggest that recalibration between optic flow and walking speed may specify an action boundary when calibrated or scaled to actions such as leaping, and possibly, the manipulation of optic flow speed has resulted in a change in the associated anticipated effort for walking a prescribed distance, which in turn influence one’s perceived action capabilities for jumping and leaping.

Enhancing wear resistance: In-situ ceramic phase precipitation for strengthening and toughening FeCoNiCrNx high-entropy alloy films

FeCoNiCr high-entropy alloys have attracted widespread attention because of their excellent toughness; however, their insufficient hardness limits their application in wear-resistant films. The introduction of non-metallic elements is an effective method for strengthening high entropy alloys films. In this study, high-entropy alloy films of FeCoNiCrNx with varying nitrogen content were fabricated using reactive magnetron sputtering. The influence of nitrogen content on the structure, mechanical properties, and tribological behavior of these high-entropy alloy films was studied. With an increase in nitrogen content, the FeCoNiCrNx film undergoes amorphization and simultaneous precipitation of Cr2N phases. At lower nitrogen flow rates (0–4 sccm), the film exhibits lower hardness (8.51–10.97 GPa) and poor wear resistance. At moderate nitrogen flow rates (8 sccm), the film exhibits enhanced hardness (12.8 GPa) and toughness, leading to favorable wear resistance (4.04 × 10−6 mm3 N−1 m−1). A further increase in the nitrogen flow rates (12–16 sccm), while raising hardness (13.08–15.17 GPa), leads to a slight reduction in toughness and consequently, a mild decrease in wear resistance (4.37–5.09 × 10−6 mm3 N−1 m−1). A biphase structure design combining FeCoNiCr high entropy alloy and ceramic (Cr2N) improved the strength and toughness of FeCoNiCrNx and significantly enhanced its wear resistance, thus enhancing its application potential.

The Influence of Company Growth, Profitability, and Free Cash Flow on Company Value with Dividend Policy as Moderating Variable (An Empirical Study on Manufacturing Companies Listed on the Indonesia Stock Exchange from 2018-2020)

This research aims to analyze the influence of a company’s growth, profitability, and free cash flow on the company’s value and the role of dividend policy in moderating this relationship. The research population is 159 manufacturing companies listed on the Indonesia Stock Exchange from 2018-2020. The sample is selected using a purposive sampling technique. There are 44 companies as the sample with 132 units of analysis. The data analysis uses Moderated Regression Analysis (MRA) supported by Eviews 9 tool. The results show that growth and profitability influence the company’s value, while free cash flow does not affect the value. A dividend policy can weakly moderate the relationship between a company’s growth and value, but it cannot moderate profitability and free cash flow to the company’s value.&#x0D; Keywords: free cash flow, dividend policy, company value; company growth; profitability

Single cavitation bubble dynamics in a stagnation flow

Jetting of collapsing bubbles is a key aspect in cavitation-driven fluid–solid interactions as it shapes the bubble dynamics and additionally due to its direct interaction with the wall. We study experimentally and numerically the near-wall collapse and jetting of a single bubble seeded into the stagnation flow of a wall jet, i.e. a jet that impinges perpendicular onto a solid wall. High-speed imaging shows rich and rather distinct bubble dynamics for different wall jet flow velocities and bubble-to-wall stand-off distances. The simulations use a volume-of-fluid method that allows us to numerically determine the microscopic and transient pressures and shear stresses on the wall. It is shown that a wall jet at moderate flow velocities of a few metres per second already shapes the bubble ellipsoidally inducing a planar and convergent jet flow. The distinct bubble dynamics allow us to tailor the wall interaction. In particular, the shear stresses can be increased by orders of magnitude without increasing impact pressures the same way. Interestingly, at small seeding stand-offs, the bubble during the final collapse stage can lift off the wall and migrate against the flow direction of the wall jet such that the violent collapse occurs away from the wall.

Population genetic structure of tropical bed bug (Hemiptera: Cimicidae) populations and their breeding pattern in Iraq.

A study was conducted to investigate the population genetic structure and breeding pattern of 140 tropical bed bugs, Cimex hemipterus (F.) (Hemiptera: Cimicidae), collected from 14 infested sites in major cities in Iraq. The samples were genotyped using a set of 7 polymorphic microsatellite markers. High genetic variety was seen among populations, with an average of 2-9 alleles per locus. The number of alleles across 7 microsatellite loci was between 6 and 18. There was a notable disparity in the alleles per loci when comparing the overall population to those within it. The overall population exhibited an average observed heterozygosity of 0.175 and an average expected heterozygosity of 0.730. Among the population, the average observed heterozygosity was 0.173, while the average expected heterozygosity was 0.673. Analysis of molecular variance (AMOVA) revealed that 93% of the genetic variability was within the populations, and 7% was among them. The genetic differentiation coefficient (FST = 0.045), indicates a low degree of genetic differentiation and a high degree of inbreeding (FIS = 0.761), as indicated by notably significant positive inbreeding coefficients. Admixed individuals were revealed using STRUCTURE and neighbor-joining phylogenetic trees, demonstrating moderate gene flow between populations and a lack of genetic structure in the regional groups. Thus, both active dispersion and human-mediated dispersion possess the potential to influence the low population genetic structure of tropical bed bug C. hemipterus populations in Iraq, which can have implications toward tropical bed bug and management strategies.

A combination weighting method for debris flow risk assessment based on t-distribution and linear programming optimization algorithm.

Debris flow risk assessment can provide some reference for debris flow prevention and control projects. In risk assessment, researchers often only focus on the impact of objective or subjective indicators. For this purpose, this paper proposed a weight calculation method based on t-distribution and linear programming optimization algorithm (LPOA). Taking 72 mudslides in Beichuan County as an example, this paper used analytic hierarchy process (AHP), entropy weight method (EWM) and variation coefficient method (VCM) to obtain the initial weights. Based on the initial weights, weight intervals with different confidence levels were obtained by t-distribution. Subsequently, the final weights were obtained by LOPA in the 90% confidence interval. Finally, the final weights were used to calculate the risk score for each debris flow, thus delineating the level of risk for each debris flow. The results showed that this paper's method can avoid overemphasizing the importance of a particular indicator compared to EWM and VCM. In contrast, EWM and VCM ignored the effect of debris flow frequency on debris flow risk. The assessment results showed that the 72 debris flows in Beichuan County were mainly dominated by moderate and light risks. Of these, there were 8 high risk debris flows, 24 medium risk debris flows, and 40 light risk debris flows. The excellent triggering conditions provide favorable conditions for the formation of high-risk debris flows. Slightly and moderate risk debris flows are mainly located on both sides of highways and rivers, still posing a minor threat to Beichuan County. The proposed fusion weighting method effectively avoids the limitations of single weight calculating method. Through comparison and data analysis, the rationality of the proposed method is verified, which can provide some reference for combination weighting method and debris flow risk assessment.

High-efficiency extraction of target particles in viscoelastic contraction-expansion microchannels.

The efficient and precise extraction of target particles is a crucial prerequisite for achieving accurate detection and analysis in microfluidic cell analysis. In this study, a symmetrical contraction-expansion microchannel with sheath flow was designed, aiming to extract target larger particles from particles of different sizes within the channel. This paper conducted numerical simulations to investigate the three-dimensional migration mechanisms of particles and performed experimental studies to examine the separation performance of particles with different sizes under varying flow rate ratios and different numbers of contraction-expansion structures. The experimental results indicate that at moderate sample flow rates and higher flow rate ratios, microchannels with fewer contraction-expansion structures are likely to achieve better performance in extracting target particles compared to microchannels with a greater number of these structures. Our work advances the application of viscoelastic contraction-expansion microchannels in particle separation. This device is easy to set up in parallel and significantly enhances throughput, providing an accurate and efficient solution for future particle separation applications.

Moderate temperature and water flow increase growth during the nursery phase of Asparagopsis armata

The red seaweed Asparagopsis armata is a target species for commercial cultivation. However, to facilitate nursery production, optimal cultivation methods for the early life stages of this species need to be developed. Therefore, this study examined the interactive effects of temperature (15 °C, 18 °C and 21 °C), irradiance (15 and 30 μmol photons m−2 s−1) and photoperiod (12 h L:12 h D and 8 h L:16 h D), and nutrient concentration (F/8 and F/4) and water flow (0.6 L min −1) on the development and growth of juvenile gametophytes of A. armata across two controlled laboratory experiments. Temperature and water flow had the greatest effect on the length of gametophytes, which was highest at 18 °C and with water flow. Gametophytes developed rapidly and were consistently largest when exposed to a 12 h L:12 h D photoperiod and growth increased when individuals were maintained at 15 μmol photons m−2 s−1 compared to 30 μmol photons m−2 s−1 under a 12 h L:12 h D photoperiod. Nutrients did not limit growth at either concentration, although contamination increased with increasing nutrient concentration and irradiance. Water flow is highly recommended during nursery cultivation of A. armata as this resulted in almost double the overall biomass productivity compared to static treatments. This work identifies critical parameters for enhancing development and growth during the early life stages of A. armata and provides fundamental information to facilitate system-specific upscaling and enable larger scale nursery production.

Can neutral genetic differentiation explain geographical variation in body size of the natterjack toad, Epidalea calamita?

Population genetic studies are crucial for evolutionary biologists because the population is the basic substrate on which evolution is forged. However little empirical evidence has been able to demonstrate the role that isolation and gene flow play in maintaining differentiation in populations at short geographic scales. Epidalea calamita exhibits a steep variation in body size and reproductive traits in southwestern Spain, associated with changes in the geological substrate. This implies a decrease of 70.9% of body mass and 28.5% in snout-vent length, on a micro-geographic scale of only 60 km. Previous results from both metamorphic and juvenile common garden experiments showed that genetic differentiation may be a causal determinant of geographic variation in adult. This study tested whether neutral genetic differentiation can explain the geographical variation in the body size observed in E. calamita. It was addressed analyzing the level of genetic structuring and gene flow among populations along the cline, comparing the genetic diversity between and within populations, as well as between ecological environments. The study showed that the geographic variation in body size observed in E. calamita has evolved in absence of geographic isolation, with moderate gene flow connecting the populations. Thus, neutral genetic differentiation cannot explain the geographical variation observed. Future studies are needed on the interaction between the genetic component with the environmental factors and will be necessary to analyze the contribution of the maternal effects in the origin and evolution of the geographical variation in the body size observed in E. calamita from southern Spain.

Premenstrual Syndrome, Anxiety, and Depression Among Menstruating Rural Adolescent Girls: A Community-Based Cross-Sectional Study.

Introduction Menstrual periods in young females can add a new challenge to the already difficult adolescent transition period. Menstrual health concerns can have extreme physical and psychosocial impacts on adolescent girls. Premenstrual syndrome (PMS) and premenstrual dysphoric disorder (PMDD) are extremely common yet underestimated.Depression in adolescentsis a mental and emotional disorder. The objective of the study was to find out the prevalence of PMS, PMDD, anxiety, and depression among rural menstruating adolescent girls and the factors associated with it. Methods This was a community-based cross-sectional study carried out among 20 rural schools for the period of one year. Sample size was calculated based on previous research. Adolescent females who had menstruated for one year were included and those with primary amenorrhea and previously diagnosed mental health abnormalities were excluded. Becks' Depression Inventory, Hamilton Anxiety Scale, and Premenstrual Symptoms Screening Tool (PSST-A) were used. Data were collected by interview technique and entered in an Excel sheet (Microsoft Corporation, Redmond, Washington, United States), and analyzed using IBM SPSS Statistics for Windows, Version 22.0 (Released 2013; IBM Corp., Armonk, New York, United States). Results Out of 430 rural adolescent girls, 180 (41.9%) were 15 years, 277 (64.4%) belonged to nuclear families, 236 (54.9%) exercised less than 30 minutes, 144 (33.5%) had menarche at the age of 13 years, 288 (67%) had regular cycles, 266 (61.9%) had moderate flow during the menstrual cycle, 302 (70.2%) had a flow duration of less than seven days, and 243 (56.5%) had dysmenorrhea. Thirty-eight (8.8%) girls had PMDD and 75 (17.4%) had PMS. Age, family status, severity of menstrual flow, duration of cycle, and presence of dysmenorrhea, depression, and anxiety had a statistically significant association with PMDD. The class/grade in which studying, cycle regularity, flow during the menstrual cycle, duration of the cycle, dysmenorrhea, anxiety, and depression status had a statistically significant association with PMS. Conclusions The menstrual cycle's impact on the mental health of rural adolescent girls should not be ignored and schools can be instrumental in improving their quality of life. Regular counselling and mental health supervision by school teachers and peer groups canbe beneficial.

Toxic Particles Deposition in the Human Respiratory Tract under Natural Inspiratory Flow

Toxic particle (PM2.5) deposition in the human respiratory tract is investigated under natural inspiratory flow. The flow physics of nostrils is asymmetric, and its effect on particle deposition needs prompt attention. An ideal 3-D CT-scan-based geometrical model of the human respiratory tract is re-constructed from the nasal cavity to the 7th generation bronchi. The pulsatile numerical simulation is performed with light (10 L/min) and moderate (40 L/min) inspiratory flow. The Lagrangian method is adopted to compute particle deposition fraction (DPF) in the airways. The suspended particle mass of 300 µg/m3 (poor air quality) (dp = 2.5 µm in diameter) is released from the inlet of airways at every time interval (∆t). The results revealed that the pattern of particle transportation is not similar in both the bronchus and particle hot spots are constituted in the airways. Findings guide optimal targeted drug delivery and the assessment of ventilation illness under hazardous exposure in distinct populations.

Thermal Interference When Recording Turbulent Pressure Fluctuations on the Surface of a Floating Device

Thermal interference is studied when recording turbulent pressure fluctuations on the surface of a floating device at specified experimental parameters of temperature stratification of an aquatic medium. The effect of distortion of the spectral levels of pressure fluctuations recorded by a sound receiver in the field of temperature inhomogeneities is studied using the example of measurements of turbulent pressure fluctuations in the boundary layer during the vertical ascent of a device from a specified depth. At moderate flow velocities exceeding 1–2 m/s, the temperature susceptibility of a piezoceramic receiver is shown to be decisively determined by its characteristic “thermal” frequency. The parameters of the threshold critical frequency, below which the temperature signal (thermal interference) prevails over the useful signal generated by pressure fluctuations, are determined. With respect to the receivers used in experiments on a floating device [7], the values of the threshold critical frequency are 130 and 215 Hz.

Molecular genetic diversity and biological activity assessment in Leptadenia reticulata from India

Leptadenia reticulata (Retz.) Wight & Arn. (Jivanti) has enormous therapeutic value in traditional medicine because of its revitalizing, rejuvenating, and lactogenic properties. Due to overexploitation and a lack of habitat, the species is rapidly disappearing. Therefore, it is essential to understand the genetic diversity as well as the biological activity profile for conservation and its medicinal use. Nine ISSR markers were used to assess the genetic diversity of fifty-five L. reticulata samples that were collected from eleven locations in India for this study. ISSR markers yielded 287 bands overall and showed 100 % polymorphism. The genetic assessment showed that diversity was relatively high at the species level but lower at the population level. AMOVA revealed 89 % variation within and 11 % between L. reticulata locations. Limited genetic differentiation (GST = 0.32) and moderate gene flow (Nm = 1.05) were observed between the locations of L. reticulata. Simultaneously, the respective chemotypes of L. reticulata from eleven locations were assessed for their phenolic and flavonoid contents, as well as antioxidant, anti-inflammatory, anti-diabetic, and antimicrobial properties using aqueous extracts. Despite minor variations, the biological activities of L. reticulata from various locations in this study did not deviate significantly. The in-vitro activities determined support its efficacy in traditional medicine. The data from this study are valuable for the efficient management of germplasm for breeding and conservation purposes to meet the ever-increasing commercial demand for L. reticulata in the herbal drug industry.