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A fused deposition modeling (FDM)-based polarization-dependent frequency-agile Frequency Selective Surface using distilled water is proposed in this paper. The FSS consists of a periodic array of vertically meandered square loops with two rectangular fluidic cavities embedded within the substrate. The resonant frequency is dynamically tuned across three distinct operating states by selectively filling one or both embedded cavities with distilled water, achieving a 47.42% tuning range in TE mode (2.15–3.45 GHz) and a 10.28% range in TM mode (3.32–3.68 GHz). An equivalent circuit model is developed to explain this tuning behavior by emphasizing the impact of fluid-induced permittivity changes in the substrate. Experimental results from a fabricated prototype validate the simulated performance, demonstrating angular stability up to 45∘. The proposed geometry is low-cost, lightweight, and energy-efficient, making it ideal for integration into adaptive communication systems, reconfigurable antennas, and electromagnetic shielding applications.
The Indian Pulsar Timing Array (InPTA) employs unique features of the upgraded Giant Metrewave Radio Telescope (uGMRT) to monitor dozens of the International Pulsar Timing Array (IPTA) millisecond pulsars (MSPs), simultaneously in the 300-500 MHz and the 1260-1460 MHz bands. This dual-band approach ensures that any frequency-dependent delays are accurately characterized, significantly improving the timing precision for pulsar observations, which is crucial for pulsar timing arrays. We present details of InPTA’s second data release that involves 7 yrs of data on 27 IPTA MSPs. This includes sub-banded Times of Arrival (ToAs), Dispersion Measures (DM), and initial timing ephemerides for our MSPs. A part of this dataset, originally released in InPTA’s first data release, is being incorporated into IPTA’s third data release which is expected to detect and characterize nanohertz gravitational waves in the coming years. The entire dataset is reprocessed in this second data release providing some of the highest precision DM estimates so far and interesting solar wind related DM variations in some pulsars. This is likely to characterize the noise introduced by the dynamic inter-stellar ionised medium much better than the previous release thereby increasing sensitivity to any future gravitational wave search.
Background: Canadian neurosurgery residency programs have an alarming 28.4% attrition rate—seven times higher than the average for most other specialties (1–4%) and double that of US neurosurgery programs. Canadian data for this issue is over 30 years old, highlighting the need for updated research. This study identifies factors contributing to Canadian neurosurgery attrition rates. Methods: Using critical constructivist theory, virtual interviews were conducted with current program directors (PDs) from Canada’s 14 neurosurgery programs and neurosurgery residents who left training between 2013–2023. Interviews were recorded, transcribed, anonymized, and iteratively coded through descriptive thematic analysis to construct an analytical framework. Results: We conducted interviews with 7 PDs and 7 former neurosurgery residents, representing 7 neurosurgery programs across Canada. The average attrition rate was 14.11% (0%–28.6%) from 2013–2023. Contributing factors include poor job prospects in Canada, resource constraints leading to high workloads, poor work-life balance, moral distress due to high levels of patient mortality, and a lack of teaching and support from staff and senior residents. Conclusions: Neurosurgery residents are the future of neurosurgery. Our study uncovers factors contributing to high attrition rates in neurosurgery training, indicating that change must come from provincial governments and within training programs to retain residents.
Background: Neurosurgery is a long and arduous training program, and the demands of neurosurgical training have led to resident burnout prevalence ranging from 11-67%, attrition, and suicide. We aimed to assess whether implementation of a weekly self-assessment tool with optional psychological counselling improves neurosurgical resident quality of life. Methods: We performed a one year prospective cohort study including 14 Calgary (intervention group) and 12 Toronto/Winnipeg residents (control group). Calgary residents utilized a mobile application (“HONE”) weekly, and all residents responded to questionnaires at baseline, midpoint and endpoint: EQ-5D-5L, Maslach Burnout Inventory (MBI), and Mayo Clinic Well-being Index (WBI). Between and within group results were compared using two-tailed t-tests. Results: Pooled baseline scores were comparable to population norms, with increased mean MBI depersonalization scores (10.28 versus 7.12, p=0.033), and more WBI “at risk” scores compared to normative data. There were no baseline differences between cohorts. EQ-5D-5L, MBI, and WBI scores were comparable between and within cohorts at all three time points. Three intervention group residents accessed psychological counselling, totalling ten sessions. Conclusions: Weekly use of the HONE application did not impact resident quality of life, although multiple residents displayed help-seeking behaviours. HONE provided tangible data for the program director to track trends in team well-being.
This study evaluated the impact of four cover crop species and their termination timings on cover crop biomass, weed control, and corn yield. A field experiment was arranged in a split-plot design in which cover crop species (wheat, cereal rye, hairy vetch, and rapeseed) were the main plot factor, and termination timings [4, 2, 1, and 0 wk before planting corn (WBP)] was the subplot factor. In both years (2021 and 2022), hairy vetch produced the most biomass (5,021 kg ha–1) among cover crop species, followed by cereal rye (4,387 kg ha–1), wheat (3,876 kg ha–1), and rapeseed (2,575 kg ha–1). Regression analysis of cover crop biomass with accumulated growing degree days (AGDDs) indicated that for every 100 AGDD increase, the biomass of cereal rye, wheat, hairy vetch, and rapeseed increased by 880, 670, 780, and 620 kg ha–1, respectively. The density of grass and small-seeded broadleaf (SSB) weeds at 4 wk after preemergence herbicide (WAPR) application varied significantly across termination timings. The grass and SSB weed densities were 56% and 36% less at 0 WBP compared with 2 WBP, and 67% and 61% less compared with 4 WBP. The sole use of a roller-crimper did not affect the termination of rapeseed at 0 WBP and resulted in the least corn yield (3,046 kg ha–1), whereas several different combinations of cover crops and termination timings resulted in greater corn yield. In conclusion, allowing cover crops to grow longer in the spring offers more biomass for weed suppression and impacts corn yield.
Exploration expeditions were conducted for 2 consecutive years in the subtropical region of North India to collect the untapped genetic diversity of Bael. A total of 15 accessions having unique traits of horticultural importance were collected and conserved in the field gene bank. Conserved germplasm was characterized for 3 consecutive years. Considerable variability was found in the morphological characters and biochemical traits. Fruit length ranged from 10.15 to 17. 68 cm, fruit circumference varied from 33.45 to 56.32 cm and fruit weight varied from 0.71 to 2.48 kg. Shell thickness was found to vary from 2.11 to 3.62 mm, whereas shell weight varied from 230 to 580 g/fruit. Number of seed sacs per fruit was found to vary from 11.17 to 15.72 and number of seeds per fruit varied from 68.00 to 113.17. Minimum seed weight was 7.04 g/fruit, whereas maximum 14.55 g/fruit. Ample variability was found in fruit yield of collected germplasm which ranged from 18.85 to 39.26 kg per plant at 16–18 years of age. Distinctive variability in biochemical traits was also found. Total soluble solids in fruit pulp were 34.92–41.13% Brix, total sugars 11.49–22.16%, acidity 0.36–0.53%, vitamin ‘C’ 9.89–17.20 mg/100 g, total carotenoids 1.43–2.40 mg/100 g and total tannins 2.50–3.58%. Available genetic diversity may be utilized for crop improvement programme.
Dementia affects millions globally, with a subset of cases potentially reversible. This study evaluates the incidence, clinical markers and treatment outcomes of reversible dementias (ReDem).
Method:
This retrospective study included 370 ReDem cases from 1810 dementia patients. The ReDem cohort was split into potentially reversible dementias (PRD) and dual etiology (DE) groups. PRD encompassed secondary, potentially treatable dementia conditions, while DE included primary degenerative dementia (DD) with ≥1 uncontrolled comorbidity or new disease that worsened symptoms.
Results:
ReDem cases comprised 20.4% (n = 370 out of 1810) of dementia patients, with ReDem patients being younger (mean 56.2 vs. 61.9 years, p < 0.001) and exhibiting shorter illness durations than DD patients (p < 0.001). Key red flags, including young age (<45 years) at onset (DD = 8.6% vs. ReDem = 18.1%), fluctuation in symptoms (DD = 3.4% vs. ReDem = 11.6%), rapid cognitive decline (DD = 6.9% vs. ReDem = 18.4), high-risk exposures (DD = 0.1% vs. ReDem = 0.8%), high-risk behavior (DD = 0.1% vs. ReDem = 2.4%) and incongruent neuropsychological findings(DD = 1.0% vs. 12.7%), were significantly more frequent in ReDem cases (p < 0.05). Odds increased with each red flag present (≥1: OR = 5.94; ≥2: OR = 20.69; ≥3: OR = 25.14, p < 0.05). Reversible etiologies included immune (20.0%), neuroinfectious (6.6%), psychiatric (7.6%), nutritional/metabolic (10.5%), neurosurgical (14.6%) and other causes (12.2%). Of the 41% (152/370) followed, 19 expired, 63.9% (85/133) reported subjective improvement, and 31.6% (42/133) showed clinical dementia rating improvement.
Discussion and Conclusion:
This large-scale study underscores the importance of comprehensive diagnostic evaluations for ReDem. Identifying and treating reversible conditions and comorbidities in DD can improve patient outcomes, emphasizing the need for thorough evaluations in memory clinics and targeted interventions in dementia care.
The application of a tube combustion system (pyrolyzer) for the batch combustion of low carbon content environmental matrices, such as soil and sediment, for determining 14C specific activity is examined. The samples were combusted at 600°C, and the CO2 species produced were trapped in 3N NaOH, precipitated as BaCO3 by adding BaCl2, and subjected to acid-hydrolysis to transfer the CO2 species to the absorber-scintillator mixture for liquid scintillation counting (LSC). The method was validated by analyzing the samples by accelerator mass spectrometry (AMS) method. The minimum detectable activity (MDA) for the method, at 2σ confidence level, was 10 Bq kg–1C (4 pMC) for a counting time of 500 min and 7 Bq kg–1C (3 pMC) for 1000 min. The capability of the method to quantify a small excess of 14C specific activity (a few Bq kg–1C or pMC) in the environment of a nuclear facility, when compared to the ambient natural background level, was demonstrated by analyzing a total of 23 soil and 7 sediment samples from the vicinity of a pressurized heavy water reactor (PHWR) nuclear power plant (NPP) at Kaiga, India. The maximum excess 14C specific activity values recorded for soil and sediment matrices were 37 ± 7 Bq kg–1C and 11 ± 7 Bq kg–1C, respectively, confirming minimal radioecological impact of the operation of the NPP on the environment. The 14C specific activity ratio for the recently fallen leaf litter and the soil underneath at most of the sampling points in the vicinity of the NPP had a mean value of 1.03 with an associated standard deviation of 0.07. Statistical tests confirm that the mean values of the data set of 14C specific activity of leaf litter and underlying soil are not significantly different.
Recent experimental studies reveal that the near-wake region of a circular cylinder at hypersonic Mach numbers exhibits self-sustained flow oscillations. The oscillation frequency was found to have a universal behaviour. These oscillations are of a fundamentally different nature in comparison with flow oscillations caused due to vortex shedding, which are commonly observed in cylinder wakes at low-subsonic Mach numbers. The experimental observations suggest an aeroacoustic feedback loop to be the driving mechanism of the oscillations at high Mach numbers. An analytical aeroacoustic model that successfully predicts the experimentally observed frequencies and explains the universal behaviour is presented here. The model provides physical insights into and informs us of flow regimes where deviations from universal behaviour are to be expected. These findings hold relevance for a wider class of non-canonical wake flows at high Mach numbers.
Supersonic intakes, under adverse operating conditions, can have unwanted oscillations of shock system internal and external to its duct, known as intake buzz. These buzz instabilities degrade intake performance by causing violent pressure fluctuations, reducing mass flow, decreasing thrust, and leading to combustion instabilities as well. This study examines the onset of this buzz in an axisymmetric intake with various throttles and investigates the effects of dynamic angular deflection of a portion of the cowl on the resulting buzz phenomena. Computations and experiments were conducted at Mach number of 2.0 to obtain the buzz in an axisymmetric intake and investigate its behaviour under various throttle conditions. Dailey-type buzz is observed to be predominant for the present axisymmetric intake, and it has been also quantified that the time period of oscillations for higher throttling ratios is not constant. A technique of dynamically varying the portion of the cowl tip about a pivot point was attempted here to eliminate the intake buzz during onset as well as during a complete buzz cycle. It has been found that the current technique is useful in seizing the buzz shock expulsion from the intake duct, hence restricting unstart and further adversities.
To identify ‘on-table optimal meatal opening size’ that predicts post-operative mastoid cavity healing in the canal wall down tympanomastoidectomy. To develop a specific, measurable, achievable, acceptable, replicable and time-bound (SMAART) meatoplasty.
Method
A double-blind randomised control trial where patients were randomly assigned to standard Portmann 3 flap and new SMAART 2 flap technique.
Results
There were 18 and 17 participants in the former and latter, respectively. Dry ear was achieved when the on-table ratio of tympanomastoid cavity volume to meatal opening size was 2:1. In a mastoid cavity of 6 ml or less, among the 2 flap patients, the majority had epithelialisation completed by the first month, meatoplasty having significantly shorter duration (12.2 versus 32.3 minutes) and cosmetically better than 3 flap.
Conclusion
Optimal meatoplasty is when tympanomastoid cavity volume ratio to meatal opening size is 2:1. When the on-table mastoid cavity is either 6 ml and less or is obliterated to 6 ml and less, the new SMAART 2 flap meatoplasty should be considered.
The therapeutic effects of soya consumption on adipokine concentrations have yielded inconsistent results in previous meta-analyses. This umbrella meta-analysis aims to investigate the impact of soya and its isoflavones on serum adiponectin and leptin levels in adults. We searched the Cochrane Central, Web of Science, PubMed and Scopus databases until October 10, 2024. The articles were restricted to those written in English. We included meta-analysis studies that evaluated the effects of soya and its isoflavones on levels of adiponectin and leptin and reported effect sizes (ES) and corresponding CI. Two independent reviewers screened all articles based on eligibility criteria and extracted the required data from the included meta-analyses. The meta-analysis was performed using a random-effects model in STATA software. Six meta-analyses of randomised controlled trials meeting the inclusion criteria were included in the current umbrella meta-analysis. The findings indicated that soya and its isoflavones did not have a significant effect on adiponectin (ES = 0·10; 95 % CI: −0·22, 0·41; P = 0·55; I2 = 51·8 %) and leptin (ES = −0·37; 95 % CI: −1·35, 0·61; P = 0·46; I2 = 71·2 %) concentrations. Subgroup analysis based on participants’ mean age, total sample size and duration was conducted. Results showed that the effect is not statistically significant in any of the subgroups. In conclusion, soya and its isoflavones could not improve the adipokines mentioned above. However, further high-quality research in different countries is required to substantiate these findings.
Indaziflam was evaluated in Connecticut and Tennessee for weed control and safety of container-grown ornamental plants. Indaziflam was applied at 49, 98, or 196 g ha−1 to container-grown ornamental plants on an outdoor gravel pad and also applied preemergence or early postemergence to weeds in a greenhouse. Ornamental plants were treated twice annually in 2020 and 2021 in Connecticut, and in 2019 and 2020 in Tennessee, with approximately 6 wk between applications. Chinese pyramid juniper, common juniper, eastern hemlock, eastern white pine, and Norway spruce in Connecticut, and ‘Andorra Compacta’ creeping juniper and ‘Black Dragon’ Japanese cedar, ‘Blue Rug’ creeping juniper, and ‘Blue Pfitzer’ Chinese pyramid juniper in Tennessee were not injured with indaziflam regardless of the rate applied. Preemergence application of indaziflam reduced densities of creeping woodsorrel, hairy bittercress, giant foxtail, and large crabgrass by 72% to 100%, depending on the indaziflam rate applied, by 28 d after treatment (DAT). When applied early postemergence, indaziflam provided 97% to 99% control of creeping woodsorrel (1- to 2-leaf), fringed willowherb (4- to 6-leaf), hairy bittercress (cotyledon to 1-leaf), and mouse-ear chickweed (2- to 4-leaf) by 28 DAT. Compared with a nontreated control, the total fresh shoot biomass reduction was 86% to 100% and 78% to 100% following preemergence or postemergence applications. Indaziflam offers a new site of action with excellent safety and weed control in the tested ornamental plants.
The whitefly, Bemisia tabaci is a cryptic species complex in which one member, Middle East-Asia Minor 1 (MEAM1) has invaded globally. After invading large countries like Australia, China, and the USA, MEAM1 spread rapidly across each country. In contrast, our analysis of MEAM1 in India showed a very different pattern. Despite the detection of MEAM1 being contemporaneous with invasions in Australia, the USA, and China, MEAM1 has not spread widely and instead remains restricted to the southern regions. An assessment of Indian MEAM1 genetic diversity showed a level of diversity equivalent to that found in its presumed home range and significantly higher than that expected across the invaded range. The high level of diversity and restricted distribution raises the prospect that its home range extends into India. Similarly, while the levels of diversity in Australia and the USA conformed to that expected for the invaded range, China did not. It suggests that China may also be part of its home range. We also observed that diversity across the invaded range was primarily accounted for by a single haplotype, Hap1, which accounted for 79.8% of all records. It was only the invasion of Hap1 that enabled outbreaks to occur and MEAM1’s discovery.
Weak-line T Tauri stars (WTTS) exhibit X-ray flares, likely resulting from magnetic reconnection that heats the stellar plasma to very high temperatures. These flares are difficult to identify through targeted observations. Here, we report the serendipitous detection of the brightest X-ray flaring state of the WTTS KM Ori in the eROSITA DR1 survey. Observations from SRG/eROSITA, Chandra X-ray Observatory, and XMM-Newton are analysed to assess the X-ray properties of KM Ori, thereby establishing its flaring state at the eROSITA epoch. The long-term (1999–2020) X-ray light curve generated for the Chandra observations confirmed that eROSITA captured the source at its highest X-ray flaring state recorded to date. Multi-instrument observations support the X-ray flaring state of the source, with time-averaged X-ray luminosity ($L_\mathrm{0.2-5\ keV}$) reaching $\sim 1.9\times10^{32}\mathrm{{erg\ s^{-1}}}$ at the eROSITA epoch, marking it the brightest and possibly the longest flare observed so far. Such intense X-ray flares have been detected only in a few WTTS. The X-ray spectral analysis unveils the presence of multiple thermal plasma components at all epochs. The notably high luminosity ($L_\mathrm{0.5-8\ keV}\sim10^{32}\ \mathrm{erg\ s}^{-1}$), energy ($E_\mathrm{ 0.5-8\ keV}\sim10^{37}$ erg), and the elevated emission measures of the thermal components in the eROSITA epoch indicate a superflare/megaflare state of KM Ori. Additionally, the H$\alpha$ line equivalent width of $\sim$$-5$ Å from our optical spectral analysis, combined with the lack of infrared excess in the spectral energy distribution, were used to re-confirm the WTTS (thin disc/disc-less) classification of the source. The long-duration flare of KM Ori observed by eROSITA indicates the possibility of a slow-rise top-flat flare. The detection demonstrates the potential of eROSITA to uncover such rare, transient events, thereby providing new insights into the X-ray activity of WTTS.
This study aimed to explore the genetic variability present in tamarind fruits. A survey and collection of twenty-nine tamarind accessions from the Bastar region of Chhattisgarh was conducted, focusing on morphological traits, biochemical properties, and mineral content. The analysis revealed significant variation in fruit characteristics, including pod weight (91.1–528.3 g), pod length (4.11–15.39 cm), pulp weight (32.88–275.68 g), number of seeds (26–237), seed weight (23.14–214.08 g), pulp percentage (26.43–52.18%), vitamin C content (54.5–92 mg/100 g), phenolic content (51.53–296.4 mg GAE/g fw), flavonoid content (75.91–280.88 mg QE/ 100 g fw), acidity (5.3–12.60%), reducing sugars (24.67–68.29%), total sugars (24.89–78.87%), calcium (0.15–1.28%), and iron content (26.6–125.7 ppm) across different accessions. Based on the overall evaluation, five accessions B21, B26, B15, B25, and B7 with the best combination of desirable fruit traits, were identified as the most promising. Additionally, five sweet accessions with acidity levels below 6% were identified (B26, B21, B15, B12, B11). Principal component analysis (PCA) was applied, identifying five principal components that accounted for 86.73% of the total variability. Correlation analysis showed a significant positive relationship between pod weight and pulp weight (r = 0.93), shell weight (r = 0.70), number of seeds (r = 0.89), and seed weight (r = 0.89). The biplot of PC1 and PC2 illustrated the distribution of accessions across all four quadrants, with B27, B8, B26, B29, B14, B18, and B13 displaying distinct differences from one another.
This work studies upper-limb impairment resulting from stroke or traumatic brain injury and presents a simple technological solution for a subset of patients: a soft, active stretching aid for at-home use. To better understand the issues associated with existing associated rehabilitation devices, customer discovery conversations were conducted with 153 people in the healthcare ecosystem (60 patients, 30 caregivers, and 63 medical providers). These patients fell into two populations: spastic (stiff, clenched hands) and flaccid (limp hands). Focusing on the first category, a set of design constraints was developed based on the information collected from the customer discovery. With these constraints in mind, a powered wrist-hand stretching orthosis (exoskeleton) was designed and prototyped as a preclinical study (T0 basic science research) to aid in recovery. The orthosis was tested on two patients for proof-of-concept, one survivor of stroke and one of traumatic brain injury. The prototype was able to consistently open both patients’ hands. A mathematical model was developed to characterize joint stiffness based on experimental testing. Donning and doffing times for the prototype averaged 76 and 12.5 s, respectively, for each subject unassisted. This compared favorably to times shown in the literature. This device benefits from simple construction and low-cost materials and is envisioned to become a therapy device accessible to patients in the home. This work lays the foundation for phase 1 clinical trials and further device development.
Face milling is performed on aluminum alloy A96061-T6 at diverse cutting parameters proposed by the design of experiments. Surface roughness is predicted by examining the effects of cutting parameters (CP), vibrations (Vib), and sound characteristics (SC). Sound characteristics based on surface roughness estimation determine the rarity of the work. In this study, a unique ANN-TLBO hybrid model (Artificial Neural Networks: Teaching Learning Based Algorithm) is created to predict the surface roughness from CP, Vib, and SC. To ascertain their correctness and efficacy in evaluating surface roughness, the performance of these models is evaluated. First off, the CP hybrid model demonstrated an amazing accuracy of 95.1%, demonstrating its capacity to offer trustworthy forecasts of surface roughness values. The Vib hybrid model, in addition, demonstrated a respectable accuracy of 85.4%. Although it was not as accurate as the CP model, it nevertheless showed promise in forecasting surface roughness. The SC-based hybrid model outperformed the other two models in terms of accuracy with a remarkable accuracy of 96.2%, making it the most trustworthy and efficient technique for assessing surface roughness in this investigation. An analysis of error percentages revealed the exceptional performance of SC-based Model-3, exhibiting an average error percentage of 3.77%. This outperformed Vib Model-2 (14.52%) and CP-based Model-1 (4.75%). The SC model is the best option, and given its outstanding accuracy, it may end up becoming the go-to technique for industrial applications needing accurate surface roughness measurement. The SC model’s exceptional performance highlights the importance of optimization strategies in improving the prediction capacities of ANN-based models, leading to significant advancements in the field of surface roughness assessment and related fields. An IoT platform is developed to link the model’s output with other systems. The system created eliminates the need for manual, physical surface roughness measurement and allows for the display of surface roughness data on the cloud and other platforms.
Blast waves have been produced in solid target by irradiation with short-pulse high-intensity lasers. The mechanism of production relies on energy deposition from the hot electrons produced by laser–matter interaction, producing a steep temperature gradient inside the target. Hot electrons also produce preheating of the material ahead of the blast wave and expansion of the target rear side, which results in a complex blast wave propagation dynamic. Several diagnostics have been used to characterize the hot electron source, the induced preheating and the velocity of the blast wave. Results are compared to numerical simulations. These show how blast wave pressure is initially very large (more than 100 Mbar), but it decreases very rapidly during propagation.