Local Packing Research Articles

Social and environmental factors influencing contemporary cases of wolf aggression towards people in Poland

Understanding factors and mechanisms causing large carnivore aggression towards people is crucial for their conservation in modern human-dominated landscapes. We present detailed descriptions of wolf attacks on people in early summer 2018 in two areas of Poland, analysis of behaviour, fitness and origin of individuals responsible for the attacks and management actions undertaken by local communities as well as governmental bodies and non-governmental organisations. We show that attacks were caused by yearling wolves (13-month-old male and 14-month-old female) originating from local packs, which appeared near households several months prior to incidents. Both individuals were positively food-conditioned and showed increasing habituation caused by irresponsible behaviour of people such as long-lasting intentional feeding or illegal keeping. Post mortem necropsy revealed obesity and serious abnormality of spleen (polysplenia) in the problem female wolf that negatively impacted her fitness and was the most likely reason for her presence near households and feeding on leftovers. Despite prolonged observations of these wolves very close to human settlements (less than 30 m), no mitigation actions were undertaken until the attacks, after which both individuals were killed. We provide several recommendations to avoid aggressive human-carnivore encounters.

Enhanced flow rate by the concentration mechanism of Tetris particles when discharged from a hopper with an obstacle.

We apply a holistic two-dimensional (2D) Tetris-like model, where particles move based on prescribed rules, to investigate the flow rate enhancement from a hopper. This phenomenon was originally reported in the literature as a feature of placing an obstacle at an optimal location near the exit of a hopper discharging athermal granular particles under gravity. We find that this phenomenon is limited to a system of sufficiently many particles. In addition to the waiting room effect, another mechanism able to explain and create the flow rate enhancement is the concentration mechanism of particles on their way to reaching the hopper exit after passing the obstacle. We elucidate the concentration mechanism by decomposing the flow rate into its constituent variables: the local area packing fraction ϕ_{l}^{E} and the averaged particle velocity v_{y}^{E} at the hopper exit. In comparison to the case without an obstacle, our results show that an optimally placed obstacle can create a net flow rate enhancement of relatively weakly driven particles, caused by the exit-bottleneck coupling if ϕ_{l}^{E}>ϕ_{o}^{c}, where ϕ_{o}^{c} is a characteristic area packing fraction marking a transition from fast to slow flow regimes of Tetris particles. Utilizing the concentration mechanism by artificially guiding particles into the central sparse space under the obstacle or narrowing the hopper exit angle under the obstacle, we can create a manmade flow rate peak of relatively strongly driven particles that initially exhibit no flow rate peak. Additionally, the enhanced flow rate can be maximized by an optimal obstacle shape, particle acceleration rate toward the hopper exit, or exit geometry of the hopper.

Effects of fixed wall and pebble size ratio on packing properties and contact force distribution in binary-sized pebble mixed beds at the maximum packing efficiency state

The binary-sized pebble mixed beds at the maximum packing efficiency state were numerical simulated by the DEM simulation to investigate the effect of fixed wall and pebble size ratios. The evolution of the distribution of packing fraction and porosity, radial distribution function and contact force were given and analyzed with emphasis on the effects of the fixed wall and pebble size ratio. The results showed that the fixed wall will result in a reduction of average packing fraction and an obvious wall effect in local porosity distribution. With the increase of the pebble size ratio, the volume fraction of the wall affected regions gradually decrease. The variation of the local packing fraction of the binary-sized pebble bed is mainly determined by the partial packing fraction of large pebbles and the partial packing fraction of small pebbles, respectively, in the regions close to the fixed wall. Furthermore, the fixed wall has little effect on the radial distribution function and contact force. However, the pebble size ratios have great influence on the radial distribution function and the contact force in binary-sized pebble bed at the maximum packing efficiency state. With the increase of the pebble size ratio, the radial distribution functions of the whole pebble beds are consistent with that of small pebbles, and approach to that of the mono-sized pebble bed. In addition, with the increase of the pebble size ratio, a higher contact force can be obtained in pebble beds.

Perception of junior doctors about local induction in Birmingham and Solihull Mental Health Foundation Trust - A quality improvement project

AimsA quality improvement project was undertaken to understand the perception of trainees about the quality of the local induction delivered by Birmingham and Solihull Mental Health Foundation Trust (BSMHFT). The primary aim was to evaluate the current local induction programme, following concerns raised by previous trainees in National Training Survey (General Medical Council) and local inspection. Our secondary aim was to devise a revised induction programme based on the trainees’ identified needs.MethodTwo anonymised questionnaire surveys were emailed to all Foundation Year Trainees, Core Psychiatry Trainees and General Practice Speciality Trainees working in BSMHFT, in December 2019 and March 2020, using trust survey monkey.ResultThe overall response to survey was 60 percent. 44.44 percent of the responses came from Core Psychiatry Trainees, with 27.78 percent responses each from Foundation Year Trainees and GP Speciality Trainees. Local induction was defined as induction specific to place of work (47.06%), trust based induction (41.18%) or all of the above options (11.76%) by trainees. 83.33% of all trainees had received local induction, whereas 16.67% did not have any local induction at the start of their post. 11.12% trainees were very satisfied and 44.44% were satisfied with local induction. 72.22 percent of the trainees were informed about of the local induction, prior to starting the post.33.3% trainees had a paper version, 22.22% had an electronic version of local induction pack, whereas 44.44% had no induction pack. 55.55% of those trainees who had an induction pack, 43.75% found it very helpful and 56.25% did not find it helpful.88.89% thought having a local induction would be helpful, whereas 11.11 percent did not feel it would help. 94.44% of the trainees completed a local orientation checklist with their consultants. Some of the trainees experienced difficulty in gaining access to electronic prescribing, electronic patient record system (RIO), and identity badges (ID) at the beginning of their post.Conclusion11.12% trainees were very satisfied, 44.44% were satisfied, 22.22 % were neither satisfied nor dissatisfied and 22 % were dissatisfied, with local induction. 88.89% of the trainees thought having a local induction pack would be helpful. Based on the trainees identified needs we developed a template for local induction pack for each post. Clinical supervisors have agreed to take the lead in preparing the local induction pack specific to their post with trainees.We aim to repeat the survey after implementing the changes identified by trainees based on their training needs.

Development of a PointNet for Detecting Morphologies of Self-Assembled Block Oligomers in Atomistic Simulations.

Molecular simulations with atomistic or coarse-grained force fields are a powerful approach for understanding and predicting the self-assembly phase behavior of complex molecules. Amphiphiles, block oligomers, and block polymers can form mesophases with different ordered morphologies describing the spatial distribution of the blocks, but entirely amorphous nature for local packing and chain conformation. Screening block oligomer chemistry and architecture through molecular simulations to find promising candidates for functional materials is aided by effective and straightforward morphology identification techniques. Capturing 3-dimensional periodic structures, such as ordered network morphologies, is hampered by the requirement that the number of molecules in the simulated system and the shape of the periodic simulation box need to be commensurate with those of the resulting network phase. Common strategies for structure identification include structure factors and order parameters, but these fail to identify imperfect structures in simulations with incorrect system sizes. Building upon pioneering work by DeFever et al. [Chem. Sci. 2019, 10, 7503-7515] who implemented a PointNet (i.e., a neural network designed for computer vision applications using point clouds) to detect local structure in simulations of single-bead particles and water molecules, we present a PointNet for detection of nonlocal ordered morphologies of complex block oligomers. Our PointNet was trained using atomic coordinates from molecular dynamics simulation trajectories and synthetic point clouds for ordered network morphologies that were absent from previous simulations. In contrast to prior work on simple molecules, we observe that large point clouds with 1000 or more points are needed for the more complex block oligomers. The trained PointNet model achieves an accuracy as high as 0.99 for globally ordered morphologies formed by linear diblock, linear triblock, and 3-arm and 4-arm star-block oligomers, and it also allows for the discovery of emerging ordered patterns from nonequilibrium systems.

DEM simulation of mechanical behavior in one-dimensional compression of crushable ceramic pebble bed

The mechanical behavior in one-dimensional compression of a crushable ceramic pebble bed for the fusion reactor, which is under different crushing ratio assumptions (0% - 2%), was numerically investigated by the discrete element method (DEM) simulation. The crushed particle was modeled by a reduction of the particle radius, therefore, the instantaneous decrease of the local stress could be produced. To guarantee the mass conservation of the particles in the pebble bed, the sub-particle insertion process was conducted. Please note that this paper mainly deals with the post of failure of the particles, hence the pebble failure process was not captured. The results showed that the crushed particles could make the pebble bed softer, and with the same Li4SiO4 pebble bed strain, the bed stress decreased as the crushing ratio grew larger. The impact of the crushing ratio on the radial and axial local packing factor was limited on the oscillating amplitude without affecting the oscillating width. Besides, the effects of the coefficient of friction and restitution under different crushing ratios were investigated. At last, the analysis of changes in the average coordination number with the bed strain under different crushing ratios was performed.

Experiment on compaction of air-dried soil under drop shocks.

For the requirement in container nursery culture that growing media should be achieved the appropriate degree compaction, this paper presents an experiment on the compaction dynamics of air-dried soil under repetitive drop shocks, as a preliminary step toward the mechanization of this compaction method. The drop height used to adjust the shock intensity included 2 mm, 4 mm, 5 mm and 6 mm. And the overall packing density of soil in a vertically stratified cylinder vessel and the local packing density in each layer were taken as indicators of soil compaction states. The stretched exponential function derived from KWW law than the empirical inverse-logarithmic function has been found to be more suitable for expressing the temporal evolution of soil compaction, according to the results of curve-fitting to test values of the overall and local density. It is inherent in this experimental configuration that the drop shock intensity even at a constant drop height varies with drop times, owing to the interaction between the soil packing itself and drop shocks caused by the combination of the packing and the container. But the function t/τf(t,H) is manifested as a straight line on the drop times t with the line slope related to the drop height H, so the soil compaction dynamics caused by its drop shocks and that under the condition with actively controlled intensity actually share the common relaxation law. In addition, the soil's one-dimensional distribution of local packing density showed a slight positive gradient as similar as monodisperse particles did.

In Situ Small-Angle X-ray Scattering Studies on the Growth Mechanism of Anisotropic Platinum Nanoparticles

Shape-controlled platinum nanoparticles exhibit extremely high oxygen reduction activity. Platinum nanoparticles were synthesized by the reduction of a platinum complex in the presence of a soft template formed by organic surfactants in oleylamine. The formation of platinum nanoparticles was investigated using in situ small-angle X-ray scattering experiments. Time-resolved measurements revealed that different particle shapes appeared during the reaction. After the nuclei were generated, they grew into anisotropic rod-shaped nanoparticles. The shape, size, number density, reaction yield, and specific surface area of the nanoparticles were successfully determined using small-angle X-ray scattering profiles. Anisotropic platinum nanoparticles appeared at a low reaction temperature (∼100 °C) after a short reaction time (∼30 min). The aspect ratio of these platinum nanoparticles was correlated with the local packing motifs of the surfactant molecules and their stability. Our findings suggest that the interfacial structure between the surfactant and platinum nuclei can be important as a controlling factor for tailoring the aspect ratio of platinum nanoparticles and further optimizing the fuel cell performance.

Hydrogen Bonds Control Single-Chain Conformation, Crystallinity, and Electron Transport in Isoelectronic Diketopyrrolopyrrole Copolymers

The combination of computational methods and advanced characterization techniques is used to highlight the role of the intramolecular hydrogen bond in thienyldiketopyrrolopyrrole (ThDPPTh) copolymerized with tetrafluorobenzene (F4) to PThDPPThF4. We investigate how the torsion potentials of ThDPPTh and isoelectronic dithiazolyldiketopyrrolopyrrole (TzDPPTz) are influenced by hydrogen bonding and translate into different conformation, molecular, structural, and opto-electronic characteristics. ThDPPTh exhibits N,S-syn orientation in the most stable conformer locked by an intramolecular hydrogen bond. In TzDPPTz, such a hydrogen bond is not possible, which leads to a “ring flip” and makes the N,S-anti conformer most stable. Copolymers with F4, PThDPPThF4 and PTzDPPTzF4, exhibit straight and curved backbones, respectively, but similar chain rigidity. These conformations are experimentally confirmed by local packing motifs from solid-state NMR spectroscopy. The differences in conformation strongly influence the opto-electronic and structural properties. X-ray scattering and atomic force microscopy reveal lamellar morphologies of both PThDPPThF4 and PTzDPPTzF4, but increased long range order, reduced paracrystallinity, and larger domains of the former. In-depth analysis of solid-state NMR spectra allows for obtaining information on absolute degrees of crystallinity, which are substantially higher for PThDPPThF4. These differences in structural properties cause field-effect electron mobilities of PThDPPThF4 to be larger by a factor of 20.

Unveiling the Local Atomic Arrangements in the Shear Band Regions of Metallic Glass.

The prospective applications of metallic glasses are limited by their lack of ductility, attributed to shear banding inducing catastrophic failure. A concise depiction of the local atomic arrangement (local atomic packing and chemical short-range order), induced by shear banding, is quintessential to understand the deformation mechanism, however still not clear. An explicit view of the complex interplay of local atomic structure and chemical environment is presented by mapping the atomic arrangements in shear bands (SBs) and in their vicinity in a deformed Vitreloy 105 metallic glass, using the scanning electron diffraction pair distribution function and atom probe tomography. The results experimentally prove that plastic deformation causes a reduction of geometrically favored polyhedral motifs. Localized motifs variations and antisymmetric (bond and chemical) segregation extend for several hundred nanometers from the SB, forming the shear band affected zones. Moreover, the variations within the SB are found both perpendicular and parallel to the SB plane, also observable in the oxidation activity. The knowledge of the structural-chemical changes provides a deeper understanding of the plastic deformation of metallic glasses especially for their functional applications and future improvements.

Stabilizing or Destabilizing: Simulations of Chymotrypsin Inhibitor 2 under Crowding Reveal Existence of a Crossover Temperature.

The effect of macromolecular crowding on the stability of proteins can change with temperature. This dependence might reveal a delicate balance between two factors: the entropic excluded volume and the stability-modulating quinary interactions. Here we computationally investigate the thermal stability of the native state of chymotrypsin inhibitor 2 (CI2), which was previously shown by experiments to be destabilized by protein crowders at room temperature. Mimicking experimental conditions, our enhanced-sampling atomistic simulations of CI2 surrounded by lysozyme and bovine serum albumin reproduce this destabilization but also provide evidence of a crossover temperature above which lysozyme is found to become stabilizing, as previously predicted by analysis of thermodynamic data. We relate this crossover to the different CI2-crowder interactions and the local packing experienced by CI2. In fact, we clearly show that the pronounced stabilization induced by lysozyme at high temperatures stems from the tight local packing created around CI2 by this smaller crowder.

Effects of coefficient of friction and coefficient of restitution on static packing characteristics of polydisperse spherical pebble bed

The effects of the coefficient of friction and coefficient of restitution on the static packing characteristics of a polydisperse spherical pebble bed are numerically investigated using the discrete element method. Several important static packing characteristics under different coefficients of friction and restitution are presented and discussed. The results show that the coefficients of friction and restitution impose opposite effects on the packing heights and global packing factor. Neither the coefficient of friction nor restitution affected the oscillation width of the wall, whereas their effects are primarily reflected in the oscillation amplitude of the radial local packing factor and the axial local packing factor distribution at the top of the pebble bed. In both the contact force distribution and coordination number distribution, a left-shifted phenomenon appearing as the coefficient of friction occurred, and only the magnitude of the maximum frequency is affected when the coefficient of restitution changed from 0.1 to 0.9. In all simulation cases, the effects of the coefficients of friction and restitution are similar to that of cross-impact.

Multi-particle FEM modeling on hot isostatic pressing of Ti6Al4V powders

The hot isostatic pressing (HIP) of Ti6Al4V powders was systematically simulated in two dimensions by using multi-particle finite element method (MPFEM) from particulate scale. Different initial packing structures formed by three kinds of powders (i.e. mono-sized powder, binary powder, and powder with normal size distribution) were firstly constructed. Subsequently, the effects of capsule shape, HIP procedure, temperature, pressure, as well as the powder type on the densification behavior of different Ti6Al4V compacts were investigated and discussed. The macroscopic property like relative density and various microscopic properties such as coordination number, stress/strain distributions of capsule and particles, deformation degree, pore filling behavior, densification mechanism and so on were quantitatively characterized. The results indicate that a larger aspect ratio (AR) is more likely to induce local order packing structure during particle rearrangement, and the proportion of powder particles with more regular deformation of Ti6Al4V compact increases after HIP. The total strain energy and deformation mechanisms of Ti6Al4V compacts are quite different with different HIP procedures. With the rise of temperature, the equivalent total strain of both the capsule and the particles became larger and the equivalent Von Mises stress decreased after HIP. In addition, Ti6Al4V powders with different size ratios will affect the performance of the compact in HIP process. The larger the particle size, the smaller the strain acting on the particle, the closer the roundness of the particle to 1. The Ti6Al4V compacts with different particle size distributions were found to exhibit different densification mechanisms. For packing of mono-sized powder, particle rearrangement destroyed bridging structure and large pores so as to accelerate the densification process. While for the Ti6Al4V compacts formed by binary powder or the powder with normal size distribution, the densification mechanism can be inferred to the extreme deformation of small particles promoting relative rigid motion of large particles.

The effect of local heat therapy on fatigue among patients with chronic obstructive pulmonary disease: A randomized controlled clinical trial

Background & Aim: Fatigue is one of the most prevalent symptoms among people with chronic obstructive pulmonary disease (COPD). Heat therapy is considered as one of the proposed methods to relieve the symptoms in these patients. Therefore, the aim of this study was to determine the effect of local heat therapy on fatigue among patients with COPD. Methods & Materials: This randomized controlled clinical trial study was conducted on 46 patients with chronic obstructive pulmonary disease referred to Allameh Bohlool Hospital in Gonabad, Iran in 2019. The participants were selected according to the inclusion criteria and were then randomly assigned to the two groups of intervention and placebo. Local packs were placed on the anterior of the chest twice a day for 23 minutes and for five days among the participants of both groups. The hot pack was 50ºC for the patients in the intervention group, but it was equal to body temperature in the placebo group. The severity of fatigue was once measured before the intervention and then one day after the final intervention in both groups. The demographic information form and Krupp fatigue severity scale were used to collect the data. Descriptive statistics and chi-square, MannWhitney, and Wilcoxon tests were used to analyze the data. Besides, the level of significance was considered at least 0.05. Results: The results indicated that the two groups were homogenous in terms of demographic information and the type of disease (P>0.05). There was no statistically significant difference between the mean score of fatigue before the intervention in the experimental and placebo groups (P=0.9). However, the mean score of fatigue decreased significantly among the intervention group patients compared to those in the placebo group (P<0.001) after the intervention. There was also a significant difference between the two groups in the mean score of fatigue before and after the intervention (P<0.01). Conclusion: According to the results, topical heat therapy is effective in reducing fatigue among patients with COPD, but it is recommended to conduct further studies before the implementation of this approach.

Atomic vibration as an indicator of the propensity for configurational rearrangements in metallic glasses.

In a metallic glass (MG), the propensity for atomic rearrangements varies spatially from location to location in the amorphous solid, making the prediction of their likelihood a major challenge. One can attack this problem from the "structure controls properties" standpoint. But all the current structure-centric parameters are mostly based on local atomic packing information limited to short-range order, hence falling short in reliably forecasting how the local region would respond to external stimuli (e.g., temperature and/or stress). Alternatively, one can use indicators informed by physical properties to bridge the static structure on the one hand, and the response of the local configuration on the other. A sub-group of such physics-informed quantities consists of atomic vibration parameters, which will be singled out as the focus of this article. Here we use the Cu64Zr36 alloy to systematically demonstrate the following two points, all using a single model MG. First, we show in a comprehensive manner the interrelation among common vibrational parameters characterizing the atomic vibrational amplitude and frequency, including the atomic mean square displacement, flexibility volume, participation fraction in the low-frequency vibrational modes and boson peak intensity. Second, we demonstrate that these vibrational parameters fare much better than purely static structural parameters based on local geometrical packing in providing correlation with the propensity for local configurational transitions. These vibrational parameters also share a correlation length similar to that in structural rearrangements induced by external stimuli. This success, however, also poses a challenge, as it remains to be elucidated as to why short-time dynamical (vibrational) behavior at the bottom of the energy basin can be exploited to project the height of the energy barrier for cross-basin activities and in turn the propensity for locally collective atomic rearrangements.

Treatment and Management of Twelfth Rib Syndrome: A Best Practices Comprehensive Review

BACKGROUND: Twelfth rib syndrome, or slipping of the 12th rib, is an often overlooked cause for chronic chest, back, flank, and abdominal pain from irritation of the 12th intercostal nerve. Diagnosis is clinical and follows the exclusion of other causes of pain. This syndrome is usually accompanied by long-suffering, consequent psychiatric comorbidities, and increased health care costs, which are secondary to the delayed diagnosis. OBJECTIVES: This manuscript is a review of twelfth rib syndrome and its management options. The review provides etiology, pathophysiology, and epidemiology of twelfth rib syndrome. Additionally, diagnosis and current options for treatment and management are presented. STUDY DESIGN: This is a narrative review of twelfth rib syndrome. SETTING: A database review. METHODS: A PubMed search was conducted to ascertain seminal literature regarding twelfth rib syndrome. RESULTS: Conservative treatment is usually the first line, including local heat or ice packs, rest, and oral over-the-counter analgesics. Transcutaneous stimulation and 12th intercostal nerve cryotherapy have also been described with some success. Nerve blocks can additionally be tried and are usually effective in the immediate term; there is a paucity of evidence to suggest long-term efficacy. Surgical removal of all or part of the 12th rib and possibly the 11th rib, as well as the next line of therapy, may provide long-lasting relief of pain. LIMITATIONS: Further large scale clinical studies are needed to assess the most effective management of twelfth rib syndrome. CONCLUSIONS: Twelfth rib syndrome is usually diagnosed late and causes significant morbidity and suffering. The actual epidemiology is unclear given the difficulty of diagnosis. Nerve blocks and surgical rib resection appear to be effective in treating this syndrome, however, further evidence is required to properly evaluate them. Familiarity with this syndrome is crucial in reaching a prompter diagnosis. KEY WORDS: Slipped rib, chronic pain, abdominal pain, chest pain, back pain, neuropathy, injection therapy, nerve block

The effect of life history events on carcass merit and price of cull dairy cows.

Cull dairy cows contribute almost 10% of national beef production in the United States. However, different factors throughout the life of dairy cows affect their weight and overall body condition as well as carcass traits, and consequently affect their market price. Therefore, the objectives of this study were: (1) to assess relationships between price ratio and carcass merit of cull dairy cows sold through several sites of an auction market and (2) to investigate the effect of animal life history events and live weight on sale barn price (BP) and price ratio (as a measure of relative price), as an indicator of carcass merit. Data from 4 dairy operations included 3,602 cull dairy cow records during the period of 2015 to 2019. Life history events data were collected from each dairy operation through Dairy Comp software; live weight and price were obtained periodically from the auction market, and the carcass data were provided by a local packing plant. Cow price in dollars per unit of live weight ($/cwt) and price ratio were the 2 outcome variables used in the analyses. Price ratio was created aiming to remove seasonality effects from BP (BP divided by the national average price for its respective month and year of sale). The association between price ratio and carcass merit traits was investigated using canonical correlation analysis, and the effect of life history events on both BP and price ratio was inferred using a multiple linear regression technique. More than 70% of the cows were culled in the first 3 lactations, with an average live weight of 701.5 kg, carcass weight of 325 kg, and dressing percentage of 46.3%. On average, cull cows were sold at $57.0/cwt during the period considered. The canonical correlation between price ratio and carcass merit traits was 0.76, indicating that price ratio reflected carcass merit of cull cows. Later lactations led to lower BP compared with cows culled during the first 2 lactations. Injury, and leg and feet problems negatively affected BP. Productive variables demonstrated that the greater milk production might lead to lower cow prices. A large variation between farms was also noted. In conclusion, price ratio was a good indicator of carcass merit of cull cows, and life history events significantly affected sale BP and carcass merit of cull cows sold through auction markets.

163 Investigating relationships between life history events, carcass quality and price of cull dairy cows sold through auction markets

Abstract Cull dairy cows comprise almost 10% of the national beef production in the United States and contribute with an important additional income source for farmers. However, cull dairy cows present high variation due to many reasons, which affect live animal characteristics, carcass traits, and market price. The objectives of this study were 1) to assess relationships between price and carcass quality of cull dairy cows sold through auction market, and 2) to investigate the effect of animal life history events on price, as an indicator of carcass quality. Data from four dairy operations in Wisconsin included 3,375 cull dairy cow records during the period of 2015 to 2019. Life history events data were collected from Dairy Comp software; live weight and price were obtained periodically from an auction barn, and the carcass data were provided by a local packing plant. Price ($/cwt) and adjusted price (price divided by the national average price) were the two outcome variables. Canonical correlation analysis (CCA) and multiple linear regression were used to investigate the relationship between variables. On average (standard deviations within parenthesis), live weight was 701.54kg (123.15kg), carcass weight of 324.97kg (68.92), dressing of 46.26% (4.92%), and price of $56.98/cwt (5.57$/cwt). CCA between adjusted price and carcass quality traits was 0.76, indicating that price is a good indicator of carcass quality. Lactation number, culling reason, month, and year of sale drastically affect price (R2 0.7532) and adjusted price (R2 0.4706). Higher live weight and days open led to higher adjusted price, and longer days dry and high milk production decreased price ($/cwt). A large variation between farms was noted. In conclusion, culling and marketing decisions should consider these factors, as an attempt to increase the price received for cull cows, and ultimately improve carcass quality.

Changes in short- and medium-range order in metallic liquids during undercooling

Abstract

Study on the packing characteristics of a special “J” shape ceramic packed pebble bed based on discrete element modeling

The packing structures of a special “J” – cylinder-tours shape ceramic packed pebble beds, which might be used in the breeding zone of future fusion blanket and the other applications were numerically studied by the Discrete Element Method. The contact force and force chain distribution and the effect of the pebble diameter on the global packing factor have been investigated. Meanwhile, the analyses of radial and axial local packing factor distribution features and coordination number distribution were performed. The results showed that the global packing factor increased with decreasing pebble diameter and the cylindrical part of the packed pebble bed had a slightly higher global packing factor than the torus part. The contact force kept decreasing after a short period of rising and the force chain distribution showed a clear difference between two parts of the packed pebble bed. Both the radial and axial local packing factor exhibited oscillation behavior but a clear difference observed in two parts. The coordination number distribution was also analyzed to investigate the contact status in the packed pebble bed. The presented results of these investigations added to the understandings of the packing structure of irregular shape packed pebble beds, hence, could provide references for fusion facility design and other areas of industry such as chemical engineering research.