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Background: Computed tomography (CT) based three-dimensional templating is increasingly being used to predict implant sizes in total knee arthroplasty (TKA). However, the existing data is heterogeneous, and the majority of studies lack adequate statistical power. This study investigated whether preoperative CT-based planning in robot-assisted TKA (RA-TKA) helps in predicting the accurate size of implant used. Methods: This is a single-center retrospective study of 632 consecutive RA-TKA surgeries. All surgeries were performed using a fully automatic Cuvis RA-TKA system. Cohen’s Kappa (κ) coefficient was used to measure the level of agreement between the predicted and the final implant sizes. Results: A total of 632 knees were operated on 384 patients. A total of 136 unilateral cases whereas 248 patients had both knees operated on. For the tibial component, in 21.7% cases a bigger implant size was used while in 11.8% cases a smaller size was used. For the femoral component, in 5.1% cases a bigger implant size was used while in 4.9% cases a smaller size was used. The agreement between the predicted and actual implant sizes was moderatefor the tibial component [κ = 0.56 (95% CI: 0.51 to 0.61); p < 0.001] and almost perfectfor the femoral component [κ = 0.87 (95% CI: 0.84 to 0.90); p < 0.001]. Conclusion: This study suggests that planning of RA-TKA using a CT-based model can be valuable to surgeons in accurately predicting the component size for femur and to a lesser degree for tibia. Future studies should investigate the potential predictors of discordance between the predicted and actual tibial implant sizes.

Objective: This study evaluated the precision of robotic-arm-assisted total knee arthroplasty (RATKA) in performing bone resection, predicting component size, managing soft tissue tension, and determining postoperative range of motion (ROM). Methods: A total of 500 participants were enrolled in this prospective cohort research. The procedures were conducted at a single facility, with a uniform method and implant design. The Cuvis system, a fully automated robot, was utilized for the study. The precise removal of bone at both the tibial and femur sites, the positioning of the implant, and the release of soft tissue were documented and then compared to the preoperative plan. Results: The distal (medial and lateral) femoral cuts had a mean absolute deviation from the plan of 0.23 mm, while the posterior (medial and lateral) femoral cuts had a mean absolute difference of 1 mm and 1.4 mm, respectively. The absolute discrepancies in the medial and lateral tibial cuts are 0.93 mm and − 0.06 mm, respectively. Out of 1000 bone resections, 980 (98%) were within < 1 mm from the preoperative plan. The predictions for the sizes of the tibial and femoral components had accuracies of 100% and 98.9%, respectively. Conclusion: These findings collectively underscore the effectiveness of the fully automated Cuvis robotic system in achieving consistent and accurate results in bone resections and implant sizing, highlighting its potential as a valuable tool in orthopedic surgery.

Machining thin-walled structures with a high aspect ratio using Wire EDM can lead to geometrical errors, primarily of two types; overcut error due to kerf formation and thermal deformation of the entire wall section. To understand the driving mechanisms behind these errors three distinct numerical models were developed. Initially, a model based on a moving heat source was created, employing the apparent heat capacity approach to predict kerf width and the associated overcut error. These insights were then utilized to formulate a transient temperature distribution model with a redesigned geometry, considering time-dependent evolution of the kerf and corresponding changes in the material properties of the sub-domains. Finally, a thermo-mechanical coupled model was developed to predict geometrical errors caused by the deflection of the wall, considering the varying stiffness of the part. A series of experiments were conducted to gain insight into the effect of the designed wall thickness on wall deflection. For the selected design profile and machine parameters, the model predicts a 62.4% reduction in thickness and a corresponding over-cut error of 188μm. Similarly, the model predicts wall deformation in the range of 6μmto 312μmfor various wall thickness levels and these findings were validated with experimental observations.

Mn-doped ZnO thin films were successfully developed via chemical spray pyrolysis technique and characterized using Field emission scanning electron microscopy (FESEM), Energy dispersive X-ray spectroscopy (EDAX), X-ray diffraction (XRD), UV–Vis Spectroscopy. An erected nanoplates-like morphology of Mn-doped ZnO films was observed through FESEM images. XRD results clearly indicated hexagonal (wurtzite) crystal structures of the undoped and Mn-doped ZnO films. Lattice parameters and volume of unit cell values were found to increase with the increase of Mn doping concentration. The optical band gap decreased from 3.28 eV to 3.26, on increase in Mn2+concentration. The ammonia gas sensing properties of the sensors based on undoped and Mn-doped ZnO films with low detection limit (15 ppm) at room temperature were investigated. The ammonia responses increased with increasing Mn doping concentration. The maximum response of 65%, 70% and 90% was acquired for ZnO, 2% and 4% Mn doped ZnO films at room temperature respectively. The ammonia sensor based on 4% Mn-doped ZnO nanostructures exhibited excellent sensing performance of ammonia concentration (15 ppm). The response and recovery times of 4% Mn-doped ZnO sensor towards 15 ppm NH3are 13 s and 7 s respectively. Gas sensing results bring promise to low operating temperature, low-cost NH3sensor based on Mn-doped ZnO, which could possibly used as real-time monitoring.

The data on production traits of FG (50% Holstein Frieson (HF) + 50% Gir), IFG (interseof FG), FJG (50% HF + 25% Jersey + 25% Gir), IFJG (interseof FJG) and R (50% HF + 12.50% Jersey + 37.50% Gir) crosses maintained at Research Cum Development Project on cattle, Mahatma Phule Krishi Vidyapeeth, Rahuri, were collected for the years 1972 to 2015. The data were analysed for estimation of means of production traits, viz. lactation length (LL), lactation milk yield per day of lactation length (LMY/LL) and lactation milk yield per day of calving interval (LMY/CI), by considering effects of period/season of calving by adopting least-square technique. The overall mean first lactation length (days) was 327.22 ± 4.15 in FG, 352.21 ± 5.14 in IFG, 331.71 ± 3.97 in FJG, 358.33 ± 3.81 in IFJG and 343.37 ± 7.52 in R genetic group. The overall mean LMY/LL and LMY/CI (kg) of first lactation was 10.47 ± 0.17 and 8.45 ± 0.16 in FG, 8.03 ± 0.12 and 6.42 ± 0.13 in IFG, 8.79 ± 0.24 and 6.99 ± 0.26 in FJG, 8.14 ± 0.10 and 6.45 ± 0.11 in IFJG and 8.38 ± 0.20 and 6.63 ± 0.22 in R genetic group, respectively. The period of calving had significant (P< 0.05) effect on lactation length, LMY/LL and LMY/CI in IFG and IFJG groups in first lactation. The variation due to season of calving on lactation length, LMY/LL and LMY/CI was significantly higher in IFJG in first lactation as compared to other groups. The genetic group had significant effect on LL, LMY/LL and LMY/CI traits.

This article presents a comprehensive development and testing of a run time assurance (RTA) filter for a torque-controlled spacecraft in free rotational motion with torque actuation limits for which the objective is to enforce a line-of-sight constraint. A nondeterministic dynamical model is considered for the spacecraft that accounts for disturbance torques, and a guaranteed safe RTA filter is constructed using recent results from mixed monotone systems theory for reachable set overapproximations and optimization-based computation of invariant sets. The RTA filter ensures that the system is always within reach of an a priori safe terminal set by computing reachable sets of the dynamics online at run time. The approach is demonstrated on the Autonomous Spacecraft Testing of Robotic Operations in Space (ASTROS) platform at the Georgia Institute of Technology, Atlanta, GA, USA. In the experiment, potentially unsafe inputs are provided by a human, and the RTA filter overrides the human-commanded inputs when necessary to guarantee safety. The controller update rate for the ASTROS platform is about 10 Hz, while the RTA filter requires about 1 ms of computation time per controller update.

More than three miles above the Arizona desert, an F-16 student pilot experienced a gravity-induced loss of consciousness, passing out while turning at nearly 9Gs (nine times the force of gravity), flying over 400 kn (over 460 mi/h). With its pilot unconscious, the aircraft turn devolved into a dive, dropping from over 17,000 ft to lower than 8,000 ft in altitude in less than 10 s. An auditory warning in the cockpit called out to the pilot “altitude, altitude” just before he crossed through 11,000 ft, switching to a command to “pull up” around 8,000 ft. Meanwhile, the student’s instructor was watching the event unfold from his own aircraft. As the student’s aircraft passed through 12,500 ft, the instructor called over the radio “two recover,” commanding the student (“two”) to end the dive. As the student’s aircraft passed through 11,000 ft, the instructor’s “two recover!” came with increased urgency. At 9,000 ft, and with terror rising in his voice, the instructor yelled “TWO RECOVER!” Fortunately, at the same time as the instructor’s third panicked radio call, a new runtime assurance (RTA) system kicked in to automatically recover the aircraft. The Automatic Ground Collision Avoidance System (Auto GCAS), an RTA system integrated on the jets fewer than two years earlier, in fall 2014, detected that the aircraft was about to collide, commanded a roll to wings level and pull-up maneuver, and recovered the aircraft fewer than 3,000 ft above the ground. The event described here occurred in May 2016. A video from the event was declassified and publicly released in September 2016, and the footage can be found at [1]. While Auto GCAS monitored the behavior of a safety-critical cyberphysical system with a ­human ­providing the primary control functions, the same concept is gaining attention in the autonomy community looking to assure safety while integrating complex and intelligent control system designs.

Nickel-based superalloys have been extensively used in the aerospace and energy sector due to their excellent mechanical properties at high pressures and temperatures. The exotic mechanical properties of Inconel-718 majorly depend on its microstructure and precipitates, which can be controlled using a heat-treatment process. In this work, a wide range of microstructures with micro-hardness (210–418 HV) and average grain size (12–88 μm) was achieved by solution treatment and aging. Electron microscopy (EBSD, SEM, EDS and TEM), analysis revealed the precipitates and microstructures. A high-volume fraction of γ' and γ″ increases the strength while δ reduces the strength of the sample. The role of microstructure, precipitates and machining parameters (such as feed and depth of cut) on the machinability of Inconel-718 was investigated. There was no direct correlation observed between average grain size and machinability due to the presence of precipitates. The solution treatment of the as received sample enables dissolution of all the precipitates (γ', γ″, δ), leaving only the matrix (γ) phase, thus improving the machinability. The machined surface was characterized using Kernel average misorientation (KAM) and Image quality (IQ) map to quantify the machined affected zone (MAZ). Both the KAM and the IQ, parameters consistently reveal MAZ with large plastic deformation, with no grain fragmentation, micro cracks, and strain localizations in the solution treated samples which are in contrast with the aged samples.

Tail biting can compromise the welfare of pigs and cause economic losses for pork producers, but little is known about the development of tail biting and its resulting impact on pigs. In this study, we investigated victimization by tail biting and the resulting impacts on the welfare and performance of pigs housed in two group sizes. Pigs (n = 432, initial body weight = 22.0 ± 3.7 kg) with intact tails were housed in large (LG = 18 pigs/pen, 12 pens) or small groups (SG = 9 pigs/pen, 24 pens) in a barn with fully slatted floors for 14 wk until market weight (120.7 ± 11.8 kg). Floor space (0.76 m2/pig) and feeder space (4 feeder spaces/9 pigs) allowance were identical between group sizes, and pigs were stratified by initial body weight and sex across treatment pens. Growth performance, pig removal, and tail damage were monitored throughout the study. Tail damage was assessed for each pig weekly and during tail biting outbreaks, using a subjective scoring system (0 = no damage; 1 = healed lesions with small scabs; 2 = puncture wounds with visible blood; 3 = wounds with signs of infection; 4 = partial or total loss of the tail). The maximal tail score (MTS) each pig received every four weeks and over the entire 14 weeks was summarized. Pigs that received MTS of ≥ 2 were considered victimized by a tail biter. Data were analyzed using Glimmix procedure with logit function and FREQ procedure with chi-square and CMH test of SAS software. Compared with SG, LG had greater MTS during the initial 4 wk (1.1 vs. 0.8, chi-square = 17.9, df = 1; P< 0.001) and reduced MTS during the last 2 wk (0.7 vs. 0.9, chi-square = 4.8, df = 1; P= 0.03), suggesting that tail damage declined as pigs grew in LG, but not in SG. The number of pigs removed for tail biting tended to be less and those removed for death and sickness tended to be greater in LG than in SG (chi-square = 7.4; df = 3; P= 0.06). Across group sizes, 68% of the removed pigs (n = 28) were victimized by tail biters (MTS ≥ 2). Between group sizes, there was no difference in time to first victimization or how often individual pigs were victimized throughout the study. Across group sizes, 45% of pigs were never victimized, but 22%, 16%, and 9% were victimized 1, 2, and 3 times, respectively. Eight percent of pigs were victimized more than three times, including 6% with MTS of 3 or 4. Pigs with MTS of 4 over the entire study period were three times more likely (odds ratios between 3.18 and 3.70; all P≤ 0.03; Table 1) to have market weight lower than the average compared with other pigs. Based on these results, we suggest that management strategies should prevent multiple victimizations or tail loss to maintain pig welfare and performance.

Tail biting is a multifactorial phenomenon with many aspects contributing to a tail biting outbreak. Little is known about how social structures influence tail biting. Our objective was to determine if litter origin impacts growth performance and tail damage caused by biting behaviors of undocked growing-finishing pigs. Pigs were separated based on their litter origin. Three treatments (12 pens/treatment) were tested: LM = all littermates (all 7 pigs/pen were farrowed and nursed by the same sow), N = non-littermates (7 pigs/pen were farrowed and nursed by 7 different sows), and H = half-group of littermates (7 pigs/pen were farrowed and nursed by 2 sows with 3 or 4 of pigs from each sow). The study was conducted in 2 replications (6 pensּ treatment-1ּ replication-1). Within each replication growth performance, mortality, and morbidity were recorded for 12 wk until pigs reached market weight. Tail damage was evaluated using a subjective scoring system: 0 = no evidence of tail biting; 1 = evidence of chewing without visible blood; 2 = evidence of tail biting with visible blood; 3 = open wounds or abscesses with signs of infection; and 4 = partial or total loss of the tail. Tail damage was assessed weekly during the study period, and the maximal tail score (MTS) that each pig received over the entire 12 wk was recorded. The number of pigs removed and the reason for removal was recorded. Data were analyzed using the mixed procedure of SAS for performance variables with a statistical model including treatment, week, and their interaction as fixed effects, replication as a random effect, and initial body weight as a covariate. A frequency procedure with a chi-square (CMH) tested treatment effects on pigs removed and MTS. Litter origin did not affect average daily feed intake (ADFI), gain to feed ratio (G:F), or pigs removed from each treatment group (all P> 0.19; Table 1), but average daily gain (ADG) of H pigs tended to be greater than that of LM pigs (P= 0.07). Maximal tail score was influenced (P= 0.008) by litter origin treatments. Pigs in LM groups had a greater percentage of MTS 0 compared with H and N groups; and H had greater severity of tail damage with 16.7% of the pigs having an MTS of 3 or greater, while both LM and N had less than 5%. Results of this study suggest that litter origin can influence severity of tail damage caused by tail biting behaviors as indicated by MTS. Future studies should focus on the differences among litter origin treatment groups regarding social interactions to further understand how social structure influences tail biting behaviors.

The geometrical error observed in the tip while machining sharp corners in thin workpieces with WEDM is studied numerically. A finite element model is developed to study the contribution of thermal effects in the tip deflection phenomenon. Initially a temperature distribution model is developed by considering formation of kerf gap and time dependent changes in material properties of different zones in the domain. The transient temperature data is fetched from the model and used in a sequentially coupled Thermo-Mechanical model to predict the deformation of tip. Numerically predicted tip deflection and the shape of the profile is validated and compared with experimental results.

Additive manufacturing processes like Selective Laser Sintering (SLS) are rapidly evolving and posing to replace conventional manufacturing routes. Parametric sensitivity analysis is vital in order to attain robust performance of Additive Manufacturing (AM) processes. This is to yield desired properties of the components fabricated given the complex process dynamics involved. Stochastic analysis of Selective Laser Sintering (SLS) process based on Monte Carlo simulation of the physics model as well as the surrogate models is found to be cumbersome or inefficient. In this work, Polynomial Chaos (PC) based response surface is utilized for stochastic analysis. The SLS physics is approximated using response surfaces utilizing lower-order polynomials. Unlike other surrogate models, sensitivity indices can be evaluated without additional computational expense. Thus, the framework is not only simple in implementation but also proven to be robust, accurate and computationally efficient with lower-order polynomials. Multiple key response properties are analyzed simultaneously for effects of input uncertainties. This was for the first-time stochastic analysis of SLS was performed with the complete and exhaustive treatment given to response data. Thus, a detailed study of aspects like parameter correlation, sensitivity analysis, percentile ranges, major distribution fit analysis and higher-order moments was performed.

Greenspace exposure is associated with psychological benefits. In this systematic review, we summarized and critically evaluated the literature on the relationship between greenspace exposure (i.e., objective and subjective assessments of interactions with nature) and psychopathology incidence and symptom severity in those with and without a clinical diagnosis. A secondary aim of our review was to examine potential interactions between greenspace exposure and urban environmental features (e.g., pollution, population density) associated with poorer mental health. We identified 40 studies published between January 1, 1981, and July 31, 2020, from PubMed and PsycINFO electronic database search. Although heterogeneous in assessments of greenspace exposure and psychopathology symptom domain, the majority of cross-sectional and longitudinal evidence found that objectively assessed greenspace exposure (e.g., satellite measures of greenery) was related to less severe symptoms and lower incidence of psychopathology in children (e.g., attention-deficit/hyperactivity disorder symptoms) and adults (e.g., depression symptoms). In addition, five studies that assessed urban environmental features suggest that greenspace exposure may show a net positive relationship with psychopathology over and above the absence of urban features. We discuss limitations of the literature and future directions, including more mechanistic work to delineate the potential cognitive, affective, and behavioral factors that may contribute to the beneficial relationship between greenspace exposure and psychological health.

We present a strategy dubbed CURD (correlations using recycle delays) to acquire chemical-shift assignments and distance restraints for proteins in a single experimental block under slow-moderate magic-angle spinning conditions. This is done by concatenating the 3D-CCC and 3D-NNC experiments, both of which individually require long experimental times for sufficient resolution and sensitivity to be realized. Unlike previous approaches, the CURD strategy does not increase the amount of radio-frequency deposition on the sample and does not require lengthy procedures to optimize any of the pulse sequence elements. Instead, time savings is obtained by using the hitherto unused recycle delay of one of the experiments (2D-CC/3D-CCC) to establish inter-residue correlations for the second experiment (2D-NN/3D-NNC). Experiments are demonstrated on a model protein at the MAS frequency of 12.5 kHz and are shown to result in time savings of the order of days for most of the routine cases.

Undoped and Co-doped ZnO nanoparticles (NPs) are prepared by a co-precipitation method. X-ray diffraction analysis confirms the undoped and Co-doped ZnO nanoparticles exhibited a hexagonal (wurtzite) crystal structure. Lattice parameters decreased slightly with Co concentration. The average crystallite size and microstrain were investigated by Williamson- Hall (W-H) analysis. The FESEM studies revealed the growth of nanoparticles with grain size about 42–65 nm. UV-visible absorption studies show the red shift in Co-doped ZnO samples. The sensor response was estimated by the change in the electrical resistance of the sample in the presence and absence of ammonia gas with fixed concentration of 10 ppm at 50 °C. The sensor response is found to be increased with the increase in doping concentration of Co. The sensor response in relation to Co concentration has been systematically studied. Co-doped ZnO sensor is well thought out as a novel gas sensor with large sensing characteristics; at the same time, the operating temperature of the sensor of 50 °C is significantly attractive to a greater extent owing to their long-term stability and less power utilization.

Nanocomposites based on α-MnO2, reduced graphene oxide (rGO)-based α-MnO2,and Fe-doped α-MnO2were successfully synthesized via the hydrothermal method. These materials were investigated for their potential applications in supercapacitors and photocatalytic dye degradation. This investigation involves a phase transition from α-MnO2to the cubic phase of α-Mn2O3, as revealed by X-ray diffraction (XRD) analysis. The electrochemical performance and photocatalytic activity were significantly enhanced through the incorporation of rGO and Fe doping into the α-MnO2lattice. Notably, the rGO-based 5 % Fe-doped MnO2(referred to as GFMO5) sample exhibits a high specific capacitance of 683.35 F/g−1, attributed to its mixed phase and defective morphology. Moreover, the introduction of Fe into the MnO2structure led to a phase transition, as confirmed by XRD, FE-SEM, and XPS results. This phase transition resulted in the remarkable degradation of methylene blue (MB) dye, achieving up to 90 % degradation under visible light irradiation. This research underscores the potential of these nanocomposite materials for advanced energy storage and environmental remediation applications.

Lightning damage to composite aircraft structures results from a concurrent and sequential interaction between arc discharge multi-physics and the anisotropic electrical and thermal composite properties. In this study, the impact of nominal 50 and 125 kA lightning strikes on damage formation in a carbon-epoxy Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) was investigated. A combination of visual inspection, ultrasonic phased array testing, destructive sectioning, and various microscopy techniques was employed to characterize the damage. Localized damage, including severe matrix decomposition, melting of polyester warp-knitting yarns, fiber splitting, and large-scale delamination, was confined to the immediate vicinity of the lightning attachment point and was accompanied by more diffuse surface damage (i.e., widespread small-scale split fiber tufts and surface primer scorching). The severity and extent of internal damage increased with higher lightning current intensities but were limited to the outermost nine-ply warp-knitted skin stack. Electrically non-conductive through-thickness Vectran™stitches and polyester warp-knitting yarns had a profound effect in mitigating lightning damage formation. These results suggest that such through-thickness reinforcement can dramatically enhance the lightning damage resistance and tolerance of composite aircraft structures.

Porous 2D covalent organic frameworks (COF) that are assembled axially through weak π-stacking interactions can provide reticular charge transport channels while playing host to kinetically stabilized reactive molecular redox states. Here we demonstrate a host–guest supramolecular charge transfer (CT) assembly using photoactive anthraquinone-based COF as an acceptor while incarcerating the electron donor N,N-dimethylaniline (DMA) inside it. Employing femtosecond broadband transient absorption spectroscopy in combination with electron paramagnetic resonance (EPR) studies, we show that the CT occurs rapidly within <110 fs after photoexcitation, subsequently leading to long-lived charge separation with 13% quantum efficiency at room temperature. The photoinduced EPR signature of the long-lived confined DMA cation radical confirms the disparate regions of charge localization while 1H–13C correlation experiments using solid-state NMR spectroscopy enumerate the packing of the amines inside the host–guest COF assembly. Our work demonstrates the potency of charge transport pathways in supramolecular assemblies for efficient charge separation which if optimally tuned should pave the way for COF-based photocatalytic reaction centers.

Swine housing systems are ever-changing to improve animal husbandry. Recently, gilts are being transitioned from gestation stalls to pens with resulting phenotypic effects being unclear. Toe growth and wear are often negated during structural analysis, with objective data of their trends being limited. Therefore, the objective of this study was to determine the impact of housing type on toe growth and wear during gestation of golts. York x Landrace gilts (n = 321) were used at the UNL ENREC swine farm. Gilts were randomly assigned to either pen (4 pigs/pen; 2.09 m2/pig) or stall (2.06 x 0.48 m) housing at 210 days of age. For analysis, gilts were lifted in a Feet First Chute (Zinpro) to permanently mark the lateral toes on the left front and back feet at ~1 cm from the coronary band. Toe length above and below the mark was measured with a digital caliper. Measurements took place before breeding (PRE), at day 30 (D30), day 57 (D57), and day 100 (D100) of gestation, and at weaning (WEAN). Estimated marginal means were calculated with regards for development group, housing type, and initial toe lengths. From PRE to D100, stall housed gilts had greater (P< 0.01) front growth (32.5 vs. 26.8 mm), similar front wear (-25.3 vs. -23.4 mm), greater (P< 0.01) back growth (39.1 vs. 34.3 mm), greater (P< 0.01) back wear (-32.3 vs. -28.1 mm), a greater (P< 0.01) total front length (41.6 vs. 39.6 mm), and a slightly longer total back length (45.5 vs. 45 mm). From D100 to WEAN, pen housed gilts had more (P< 0.05) back wear (-5.12 vs. -4.32 mm) and subsequently less (P< 0.01) total back growth (4.88 vs. 6.50 mm); with no other differences showing significance. These results suggest that housing can alter feet conformation with stall developed gilts having longer toes when entering farrowing.

Tail biting is both an economic and welfare problem of grower-finishing pigs. This destructive chewing behavior of tails of pen-mates causes challenges for farmers who raise pigs with intact tails, resulting in the need to find management solutions. Our objective was to determine if group size influences growth performance and tail damage caused by biting behavior of undocked growing-finishing pigs. Pigs (n = 432; initial BW = 22 ± 3.8 kg) with intact tails were allocated to small pens or large pens on totally slatted floors, with equal ratio of barrows to gilts in each pen and balanced for average initial BW across pens. Small pens (SM; n = 24) housed 9 pigs/pen and large pens (LG; n = 12) held 18 pigs/pen. Floor space allowance (0.76 m2/pig) and feeder-space allowance (4 feeder spaces/9 pigs) were consistent across group sizes. Pigs were weighed individually and feed intake was recorded on a pen basis every 4 weeks for 16 weeks until market weight (120 kg ± 3.8 kg), from which ADG, ADFI, and Gain:Feed were calculated. Number of pigs that were dead (mortality) and removed (morbidity) from the study due to tail biting, lameness, and other health issues were recorded throughout the study period. Tail damage was evaluated using a 0 to 4 scale scoring system: 0 = no evidence of tail biting; 1 = evidence of chewing without visible blood; 2 = evidence of tail bitten with visible blood and no signs of infection; 3 = open wounds or abscesses with signs of infection; 4 = partial or total loss of the tail. Tail damage was assessed once weekly during the study period, and the maximum tail score (MTS) that each pig received over the entire 16 weeks was recorded. Data were analyzed using SAS software, with a mixed procedure for performance variables and a frequency procedure with chi-square test for mortality, morbidity, and MTS. Group size did not affect growth performance (all P> 0.70; Table 1), mortality, or morbidity (Chi-square = 2.33, df = 2; P= 0.31). However, group size affected MTS (chi-square = 10.78, df = 4; P= 0.03). Pigs in SM experienced a marginally lower prevalence of tail biting compared with LG (16% vs. 9% of pigs receiving an MTS of 0); but greater severity with 13.0% of pigs in SM vs. 7.4% of pigs in LG receiving an MTS of 4. These results suggest group size did not influence growth performance, mortality, or morbidity; but affect severity of tail damage caused by tail biting. Compared with LG, SM had more pigs that lost their tails due to tail biting, which seriously compromised pig welfare.

Throughout the Rolling Plains and Cross Timbers ecoregions of Texas, native grassland plant communities have been converted into low-diversity plant communities by long-term, intensive overgrazing by cattle and fire suppression. Much of the historical plant community has become dominated by annuals, Texas wintergrass (Nassella leucotricha),and honey mesquite (Prosopis glandulosa).This degradation has been so severe that many native bird species, including Northern bobwhite (Colinus virginianus),have experienced drastic population declines. We conducted a small-plot study to determine effective management actions for transforming mesquite savanna−Texas wintergrass communities to diverse native plant communities supportive of native wildlife species. We tested multiple management practices following mechanical mesquite brush removal, including seeding, timed treatments of herbicide, prescribed burns, and high-intensity, short-duration cattle grazing. Results indicated that plots receiving early spring treatments of herbicide followed by burning and grazing over 2 consecutive yr best reduced cool-season grasses and promoted overall restoration goals by increasing native warm-season grass and forb establishment.

This article gives classification of micromanufacturing in general and micromachining processes in particular. For different micromachining processes, one can have different kinds of operations through which different features, shapes, accuracy, precision, and dimensions can be achieved. This article as Part I reports an overview of only three processes as diamond turn machining (a class of traditional micromachining processes), electrochemical micromachining, and focused-ion-beam micromachining (a class of advanced micromachining processes). About all these three processes, a brief introduction to the mechanisms of material removal is reported followed by the new developments in each process which are discussed independently. In various sections, some areas where research work needs to be done are identified and very briefly discussed.

Ceramics, being brittle in nature are highly prone to surface damage during machining. However, at depths of cut lower than a critical depth of cut, brittle materials undergo microscopic plastic shearing resulting in a crack-free surface. The transition from ductile to brittle takes place over a finite time and depth variation. The identification and characterization of the transition zone is important to attain damages free surface grinding. This work focuses on the identification of the ductile-brittle transition (DBT) zone in yttria stabilized sintered zirconia via the analyses of the force signatures. An algorithm has been developed for the prediction of the onset and end of the transition zone based on the gradients and fluctuations in the cutting force signals. The visual inspection of the ground surface validates the proposed methodology based on force signal processing. The transition zone characteristics were found to be affected by the process parameters and the tool geometry. The increase in the scratch speed reduced the transition onset depth but had negligible effect on the transition end depth. Smaller tool tip radius resulted in increased surface damage whereas larger tip radius gave a relatively smoother surface finish. This methodology of accurate prediction of DBT zone using cutting/thrust force behavior allows the manufacturers to achieve crack-free surfaces in brittle materials without keeping track of cutting depth during machining. Thus, the prediction of the ductile regime by the analysis of force signals opens new horizons in deciding threshold force and depth values in real time, which should be maintained to achieve a damage free surface during grinding.

Introduction: The coronavirus disease (COVID-19) was declared as a pandemic by the World Health Organization on 30th January 2020 so the practice of dentistry and orthodontics has come to a standstill.Description: The COVID-19 affects different people in different ways. The most common symptoms resemble very much to that of seasonal flu. Patients experience dry cough, rising fever and tiredness or shortness of breath. Clinical practice of Orthodontics during COVID-19 pandemic, facing such a difficult and highly contagious disease There are two ways in which you can handle them, remotely guiding and helping them with help of telecommunication and you can prepare your clinic by following all sanitization protocols and then keeping the clinic open only for such patients. Usage of Environment Protection agents, N95 masks, PPE kits and HEPA filters are some of the basic things to go about.Conclusion: With the ever changing scenario of the COVID-19 continuous monitoring of the local situation and one eye on the latest instructions given by the WHO and Health ministry should be followed.

Flash droughts are a recently recognized type of extreme event distinguished by sudden onset and rapid intensification of drought conditions with severe impacts. They unfold on subseasonal-to-seasonal timescales (weeks to months), presenting a new challenge for the surge of interest in improving subseasonal-to-seasonal prediction. Here we discuss existing prediction capability for flash droughts and what is needed to establish their predictability. We place them in the context of synoptic to centennial phenomena, consider how they could be incorporated into early warning systems and risk management, and propose two definitions. The growing awareness that flash droughts involve particular processes and severe impacts, and probably a climate change dimension, makes them a compelling frontier for research, monitoring and prediction.

Abstract

Solid-state NMR is a powerful tool to measure distances and motional order parameters which are vital tools in characterizing the structure and dynamics of molecules. Magic-angle spinning (MAS), widely employed in solid-state NMR, averages out dipole–dipole couplings that carry such information. Hence, rotor-synchronized radiofrequency (RF) pulses, that interfere with MAS averaging, are commonly employed to measure such couplings. However, most of the methods that achieve this, rotational echo double resonance (REDOR) being a classic example, require RF amplitudes that are greater than or equal to the MAS frequency. While feasible at MAS frequencies <40 kHz, these requirements become prohibitively large for higher MAS frequencies (40–110 kHz), which are now commercially available. Here, we redesign the REDOR experiment so that RF amplitudes as low as 0.5–0.7 times the spinning frequency can be used. This sequence, name deferred rotational echo double resonance (DEDOR), thus extends the utility of this method to the fastest MAS frequencies currently commercially available (111 kHz). The generality of this strategy is shown by extending it to other methods that utilize the same principle as REDOR. They will be useful in obtaining structural parameters for a wide range of molecules using solid-state NMR under fast MAS with the additional advantage of higher spectral resolution under these conditions.

In this work, controlled bidirectional deformation of suspended nanostructures by site-specific ion irradiation is presented. Multiscale modeling of the bidirectional deformation of nanostructures by site-specific ion irradiation is presented, incorporating molecular dynamics (MD) simulations together with finite element analysis, to substantiate the bending mechanism. Strain engineering of the free-standing nanostructure is employed for controlled deformation through site-specific kiloelectronvolt ion irradiation experimentally using a focused ion beam. We report the detailed bending mechanism of suspended silicon (Si) nanostructures through ion-induced irradiations. MD simulations are presented to understand the ion–solid interactions, defects formation in the silicon nanowire. The atomic-scale simulations reveal that the ion irradiation-induced bidirectional bending occurs through the development of localized tensile–compressive stresses in the lattice due to defect formation associated with atomic displacements. With an increasing ion dose, the evolution of localized tensile to compressive stress is observed, developing the alternate bending directions calculated through finite element analysis. The findings of multiscale modeling are in excellent agreement with the bidirectional nature of bending observed through the experiments. The developed in situ approach for bidirectional controlled manipulation of nanostructures in this work can be used for nanofabrication of numerous novel three-dimensional configurations and can provide a route toward functional nanostructures and devices.

Distributed control has emerged as a major focus in the systems and controls area, with multiagent robotics playing a prominent role both as a canonical instantiation of a system, where control decisions must be made by individual nodes across an information-exchange network, and as a rich source of applications [1]-[5]. These applications include environmental monitoring [6], collective materials handling [7], construction [8], disaster response [9], and precision agriculture [10].

Nanomaterials have high surface-to-volume ratios and possess unique physiological and biochemical properties modulating a wide range of reactions causing inflammation and cell toxicity. The present work was aimed to evaluate histopathological and biochemical changes in organs of the glucose metabolism after treatment with zinc oxide nanoparticles (ZnONP) in diabetic Wistar rats. Induction of diabetes was done with Streptozotocine and animals were treated with ZnONP in three graded doses in different groups. Glipizide was added in standard treatment and one of the ZnONP groups. Overall histopathological changes were observed as mild to moderate in diabetic animals that received no treatment and minimal in those that received standard treatment as Glipizide. The animals that received ZnONP as a treatment showed minimal to no abnormality detected on histopathology. Biochemical analysis revealed that ZnONP possess antidiabetic and lipid lowering activity which was consistent with histopathology. It is concluded that ZnONP play pivotal role in glucose metabolism and should be investigated further so that they can be introduced into diabetes treatment.

Titanium nanotubes (TNT) possess unique properties owing to their high surface-to-volume ratio and thus utilized in various applications. For the fabrication of TNT, anodization method is preferred due to its simplicity and low cost. In this study, titanium nanotubes were produced via anodization method and the effect of various parameters such as applied voltage, anodization time, and concentration of H3PO4in the electrolyte mixture (i.e. NH4F and ethylene glycol) on the average inner diameter of the TNT were investigated. A novel methodology for machining titanium with electrochemical micromachining (ECMM) has been put forward with modification in the topography by producing TNT on the titanium surface. The optimum parameters for producing well-ordered uniform TNT arrays have been found to be 3 hours of anodization with an electrolyte mixture of 0.3 M H3PO4and 0.3 M NH4F at 30 V potential. The anodization with these optimum parameters resulted in the uniform TNT arrays with an average inner diameter of 48±5 nm. ECMM has been demonstrated on the titanium surface with and without TNTs. It is concluded that the dissolution along the depth direction is higher than the radial dissolution for the titanium surface with TNTs. In summary, the surface with TNTs aids the ECMM machining performance of titanium.

ABSTRACTRain-on-snow (ROS) has the potential to produce devastating floods by enhancing runoff from snowmelt. Although a common phenomenon across the eastern United States, little research has focused on ROS in this region. This study used a gridded observational snow dataset from 1960–2009 to establish a comprehensive seasonal climatology of ROS for this region. Additionally, different rain and snow thresholds were compared while considering temporal trends in ROS occurrence at four grid cells representing individual locations. Results show most ROS events occur in MAM (March-April-May). ROS events identified with rainfall >1 cm are more frequent near the east coast and events identified with >1 cm snow loss are more common in higher latitudes and/or elevations. Decreasing trends in DJF (December-January-February) ROS events were identified near the coastal areas, with increasing trends in the northern portion of the domain. Significant decreasing trends in MAM ROS are likewise present on a regional scale. Factors playing a role in snowpack depth and rainfall, such as movement of storm tracks in this region, should be considered with future work to discern mechanisms causing the changes in ROS frequency.

Titanium alloys have found growing applications in aerospace, biomedical and marine industry. However, extreme hardness and strength cause difficulty in machining of titanium alloys. This is further complicated by the requirements of micro-features on hard to machine alloys. Micro-electro discharge machining (micro-EDM) is being investigated to match the requirement. However, slower removal rates and thermal effects are the issues in thermal erosion-based EDM process. In this work, we have investigated the efficacy of using carbon nanofibres (CNFs) mixed with the dielectric fluid for micro-machining of Ti-6Al-4V using micro-EDM. It is observed that the addition of CNFs not only improves electro-discharge frequency, material removal rate but also improves the surface roughness. Added nanofibres lowered the material migration and increased spark gap. We noted a significant influence of mixing CNFs in the dielectric fluid for enhancing machining performance characteristics in μEDM during micro hole generation on Ti-6Al-4V alloy.