Standard Grade Research Articles

Intraoperative arthroscopic classification tool for posterolateral elbow instability

Introducing and implementing an arthroscopic classification tool for posterolateral elbow instability. Thirty arthroscopies were performed on 30 patients, and all recordings were collected, blinded, and labeled. Three orthopedic surgeons reviewed and scored all 30 recordings three times with a period of at least seven days in between to analyze the intraobserver and interobserver reliability. The classification consisted of five different grades. Indications for elbow arthroscopy included impingement (n=7), osteochondritis dissecans (n=5), pain (n=7), osteoarthritis (n=6), and other (n=5). The kappa value for intrarater reliability was 0.71, indicating good reliability, while the kappa value for inter-rater reliability was 0.38 indicating fair reliability. This new classification is a tool for an arthroscopic assessment of PLRI and can be used as a standardized grading system for further research and communication between orthopedic surgeons. We demonstrated good intrarater reliability (k=0.71) with fair inter-rater reliability (k=0.38). However, further research is necessary to study the clinical significance.

Assessment of water resource vulnerability under changing climatic conditions in remote Arctic communities

The influence of environmental change and increased resource demand on freshwater supplies in Arctic Canada emphasizes a critical need to anticipate future freshwater supply capabilities. A paucity of infrastructure and capacity has historically limited efforts to address water resource vulnerability for Arctic communities; therefore, we developed a locally relevant framework that quantifies liquid water volume under varying climate and demand scenarios. We incorporated vulnerability grading standards based on existing indices to assess the viability of single-source water reservoirs. Using municipal demand and meteorological data from the Arctic Canadian hamlets of Igloolik and Sanirajak, Nunavut, we forecasted end-of-winter reservoir volumes for 2022–2035 under a number of scenarios; baseline supply was assessed in relation to system capacity for summer recharge, anomalous seasonal events, and deviations in available ice-free days for recharge. Our assessment indicated that the respective reservoirs were highly responsive to air temperature and ice thickness. Cases of complete reservoir depletion (≤0 % available liquid water) were prevalent across simulated years, whereas normal reservoir conditions (30 ∼ 60 % available liquid reservoir water) were comparatively limited. We found that neither community had sufficient capacity within their current infrastructure for supplying freshwater over a typical planning horizon. Our analysis highlights the need for locally-specific planning related to freshwater supply to ensure sustainable capacity under a variable climate future. Together, our framework and models are an effective tool for assessing water resource vulnerability that can be linked to existing water resource indices to inform municipal planning and mitigation strategies.

A retrospective study on application of a classification criterion based on relative intervertebral tension in spinal fusion surgery for lumbar degenerative diseases

BackgroundAs an important part of spinal fusion procedure, the selection of fusion cage size is closely related to the curative effect of the surgery. It mainly depends on the clinical experience of surgeons, and there is still a lack of objective standards. The purpose of this study is to propose the concept of relative intervertebral tension (RIT) for the first time and its grading standards to improve the surgical procedures of lumbar interbody fusion.MethodsThis retrospective study was conducted from January 2018 to July 2019. A total of 83 eligible patients including 45 men and 38 women with lumbar degenerative disease underwent transforaminal lumbar interbody fusion (TLIF) were included in this study. A total of 151 fusion segments were divided into group A, group B and group C according to the grading standards of RIT. In addition, parameters of intervertebral space angle (ISA), intervertebral space height (ISH), intervertebral space foramen (IFH), fusion rates, cage-related complications and cage heights were also compared among the three groups.ResultsThe ISA in group A was the smallest among three groups in contrast with group C with largest ISA at the final follow-up(P < 0.05). The group A presented the smallest ISH and IFH values(P < 0.05), compared with group B with the largest ISH and IFH values(P < 0.05). These two parameters in the group C were in-between. The fusion rates of group A, group B and group C were 100%, 96.3% and 98.8% at the final follow-up, respectively. No statistical difference in fusion rates and cage-related complications occurred among the three groups(P > 0.05), and a certain correlation between ISH and RIT was also observed.ConclusionsThe concept of RIT and the application of its clinical grading standards could simplify the surgical procedures of spinal fusion and reduce cage-related complications.

Analysis of BPM and Temperature Data Retrieval in Smartband Design with Android Applications Using the Multiplexing Method

Monitoring and recording of patient medical records is very necessary if there are symptoms of a disease that must be taken quickly so that the patient's condition does not worsen and find out how the pattern of a disease attacks the body's condition, this is so that the patient's history data can be checked by a doctor to make it easier and improve the accuracy of the doctor's diagnosis. In its application, the use of two sensors for smartband requires the use of a multiplexer method so that the data does not collide with each other because of the similarity of the two sensor systems. In this study, the Wemos D1 Mini microcontroller was used to process BPM and temperature data, as well as to process the time of using the multiplexer of the two sensors, then the BPM and temperature values ​​were displayed on the OLED screen. Based on the results of the research that has been done, it can be concluded that the smartband has an error (error value) which is still within the allowable tolerance limit of ±5%. This study has the advantage of a portable device design and is very suitable for daily use to monitor the patient's condition, so that patients are not disturbed by the presence of this smartband. This research has a development that is the use of a larger battery so that its use can last longer, then the use of a temperature sensor that has a medical grade standard.

A comparative study between gel card method and manual method for Coomb\'s test

The main objective of this study is to compare the Gel Card method and the Conventional Tube method for Coomb’s test. The standard procedures were being followed while performing the above mentioned two test. Based on an 8 months study, Gel card method was proven to be more reliable in concordance with its calculated p-value and the sensitivity. The advantages and disadvantages of which have been mentioned in the following. For Gel Card method, the principle of saphadex gel as a semi-solid medium is being used to trap any agglutination. For the Conventional Tube method, the SOP was being followed involving cell washing and confirmation via microscopy for any micro-clumps. The use of polyspecific antiglobulin was implemented for both the above test. The study showed p-value for Gel Card method to be &amp;#60; 0.05 which proves to be significant and the sensitivity of Gel Card method was also better compared to the Conventional Tube method. Our study showed that gel card is more sensitive, easy to perform and lesser time consumption, lesser sample volume plus standardized reporting. Results of Gel card can be preserved for 3-4 days. Avoidance of interobserver variability is also an added benefit due to the standard grading system. It is therefore an excellent method for detecting agglutination compared to the Conventional Tube method.

Research Progress of SOA Formation from Anthropogenic VOCs Under Complex Pollution Condition

Although the air quality in China has been greatly improved in recent years, the air pollution remains severe. The annual mean PM2.5 concentrations have not met the second grade of the National Ambient Air Quality Standards in China and are still much higher than the guideline value of the World Health Organization. Thus, the PM2.5 concentration needs to be further reduced. Secondary organic aerosol (SOA) is an important component of PM2.5 and has an important impact on air quality, global climate change, and human health. Therefore, understanding the formation mechanism of SOA is an important basis to control SOA and further reduce PM2.5. As an important precursor of SOA, volatile organic compounds (VOCs) can be oxidized by oxidants such as ·OH, NO3[KG-*2/3]·, Cl·, and O3 to generate low volatile organic compounds and further to form SOA through gas-particle partitioning, homogeneous nucleation, aqueous phase reaction, and heterogeneous reaction processes. The formation of SOA can be affected by many factors, such as the types and initial concentrations of VOCs, VOCs/NOx ratios, relative humidity (RH), temperature (T), seed aerosols, oxidants, aqueous phase process, and photochemical process. The observed SOA concentration is always underestimated by air quality models because a comprehensive understanding of the complexity of SOA chemical composition and formation mechanisms is still lacking, especially that under the highly complex air pollution conditions in China. Therefore, the formation mechanism and influencing factors of SOA under highly complex air pollution conditions have become an important concern in the field of atmospheric sciences. Recently, much laboratory work has focused on the formation of SOA under complex conditions. The research progress of SOA formation from different anthropogenic VOCs are reviewed here, and the methods used and the impact of different influencing factors on SOA formation are introduced. Finally, the key scientific issues that exist in the research of the SOA mechanism at present are put forward, and the future research direction is projected.

Comparative Analysis of Chinese Proficiency Grading Vocabulary Between HSK2.0 and HSK3.0

As the top-level design of international Chinese education at the HSK3.0 stage, Chinese Proficiency Grading Standards for International Chinese Language Education are improved in many aspects compared with International Curriculum for Chinese Language Education (Revised Edition) at the HSK2.0 stage. The requirements for vocabulary part of these two files are quite different in terms of total vocabulary quantity, difficulty, marking method and content. After comparative analysis, it is found that the new standard is more inclusive, practical and innovative in vocabulary part.

Structural Safety Inspection of Reinforced Concrete Structures Considering Failure Probabilities of Structural Members

Regular safety inspections of existing reinforced concrete (RC) structures are required according to the regulations and criteria set by each country. In South Korea, the safety inspection regulations provided by the Korea Infrastructure Safety and Technology Corporation (KISTEC) are followed. These regulations were developed based on fuzzy theory to avoid subjective decisions, and provide standardized deterioration grades for member types, floors, and the entire structure. However, the safety inspection regulation by the KISTEC often provides unconservative evaluation results. In particular, as the importance factors of beam and slab members are set lower than those of other members, there are cases in which deteriorations occurring in beams and slabs are not properly reflected in the floor level evaluation. In this study, to overcome such limitations, case studies were carried out and modified importance factors for structural member types were proposed considering the failure probabilities of each member type based on the reliability theory. The importance modification factor was calculated based on the strength ratio of structural members so that the more dangerous the members are, the more impact they give on the evaluation. Overall, compared to the KISTEC method, the proposed method provided conservative but practical assessment results, and it was found that the proposed importance factors can be very useful to properly reflect the effects of damaged members on the deterioration status evaluation of the floors and the entire structure.

Contamination and human health risk assessment of heavy metal(loid)s in topsoil and groundwater around mining and dressing factories in Chifeng, North China

Chifeng is a concentrated mining area for non-ferrous metal minerals, as well as a key prevention and control area for heavy-duty enterprises. This situation necessitates an effective ecological and human health risk assessment of heavy metal(loid)s driven by the wide distribution of metal ore processing, mining, and smelting factories in Hexigten Banner and Bairin Left Banner. We conducted surveys to assess the levels of heavy metal(loid)s (Cr, As, Pb, Cd, and Hg) in the topsoil and groundwater of the areas. The results indicated that the concentrations of As, Cd, and Pb in partial soil samples exceeded the environmental quality standards of Grade II. Based on contamination assessments, such as geoaccumulation indices and pollution indices, we inferred that Cd, Pb, and As were primary pollutants in topsoil. Potential ecological risks when considered as part of the average risk indices (RI) are up to 1626.40 and 2818.76, respectively, in the two areas. Comparative analysis revealed that Cd posed a very high potential ecological risk, followed by As. Moreover, the evaluation showed that the three exposure pathways of carcinogenic and non-carcinogenic risk followed a descending order: inhalation > ingestion > dermal contact, except for Pb. Arsenic in topsoil posed a potential non-carcinogenic risk to human health, while there were no adverse effects of As in groundwater. In addition, the average total carcinogenic risk for As in the two areas, as well as the risk of Pb in the topsoil of Bairin Left Banner and all the five heavy metal(loid)s in groundwater, exceeded human tolerance. Pb–Zn mines caused higher human health risks. In addition, the tandem contamination of heavy metal(loid)s in soil and groundwater was not obvious. This research study provides a basis for pollution remediation to control heavy industry-induced ecological and health risks of heavy metal(loid)s.

Using the Concrete–Representational–Abstract Sequence to Teach Conceptual Understanding of Place Value, Rounding, and Expanded Notation

This study investigated the effects of a place value intervention with third–grade students with learning disabilities. The intervention added content to a research–based intervention using the concrete–representational–abstract (CRA) sequence. The added content reflected current mathematics standards for third grade. Students’ place value understanding was measured using probes in which students had to identify the value of each digit within a three–digit number, round three–digit numbers to the nearest 10 or 100, and write three equations showing an expanded form of a three–digit number. A single–case, multiple–probe–across–students design showed a functional relation between CRA and completion of items requiring place value understanding. Students completed a generalization task by estimating the sum of a given equation.

Stepwise regression of agarwood oil significant chemical compounds into four quality differentiation

&lt;span&gt;This paper gives precise summary on the application of stepwise regression model based upon the pre-process analysis of boxplot for four chemical compounds into four different qualities of agarwood oil. In the global market, agarwood oil is acknowledged as a pricey and valuable nature product owing to its benefits. Unfortunately, there is no standard grading method for agarwood oil grade classification. Intelligent model in grading the quality of agarwood oil is crucial as one of the efforts to classify the agarwood quality. The main model chosen in this study is stepwise regression by concerned specific parameter which is the value of correlation coefficient, R2. To achieve this goal, four out of eleven significant compounds of agarwood oil that consist of 660 data samples from low, medium low, medium high and high quality are representing the input. The independent variables are X1, X2, X3 and X4 which refer to the ɤ-Eudesmol, 10-epi-ɤ-eudesmol, β-agarofuran and dihydrocollumellarin compounds, respectively. MATLAB software version r2015a has been chosen as the simulation platform for this research work. The result showed that the stepwise regression model has a correlation coefficient of 0.756 and p-value less than 0.05 significance level which successfully passed the performance criteria toward regression value.&lt;/span&gt;

Symblepharon in kittens: a retrospective study of 40 kittens and 54 eyes (2002-2022).

The aim of this study was to retrospectively evaluate the signalment, treatment, surgical technique and outcomes for feline symblepharon. A retrospective medical record review and standardized grading of clinical descriptions and photographs was undertaken. Forty kittens (54 eyes) aged 3-46 weeks had symblepharon of five types in various combinations: eyelid deformation (24 kittens; 32 eyes); ankyloblepharon (four kittens; four eyes); conjunctiva-to-conjunctiva (11 kittens; 12 eyes); third eyelid-to-conjunctiva (24 kittens; 29 eyes); and corneoconjunctival adhesions (14 kittens; 16 eyes). At initial presentation, 23 (43%) eyes were affected by one type of symblepharon, 25 (46%) eyes by two types and six (11%) eyes by three types; 11 (20%) corneas were ulcerated. Twenty-four (44%) eyes of 18 (45%) kittens were managed medically. Surgery was performed under general anesthesia/sedation (30 occasions) or topical anesthesia (21 occasions) on 30 (56%) eyes of 22 kittens; 12 eyes (40%) underwent multiple surgeries. Four techniques were commonly employed: separation of conjunctival-to-conjunctival adhesions ± eyelid margins (14 eyes); resection of third eyelid adhesions ± temporary tacking of the third eyelid (modified Arlt's pterygium technique; 18 eyes); en bloc resection of the third eyelid (two eyes); and separation of corneoconjunctival adhesions (14 eyes). Median duration of follow-up was 55 days (range 1-1051). Median symblepharon grade in kittens treated surgically improved for all types except corneoconjunctival symblepharon. Median symblepharon grade in kittens receiving medical management remained the same or improved. Corneoconjunctival symblepharon opacity decreased for eyes treated surgically but increased for eyes treated medically. Three eyes were enucleated due to complications of corneoconjunctival symblepharon. At final presentation, symblepharon persisted in 46 (85%) eyes; however, menace response was evident in 13/16 eyes and dazzle reflex in 23/23 eyes. Symblepharon is a heterogeneous group of conditions with diverse anatomic involvement, clinical appearance and impact, optimal treatment and prognosis for vision.

Differentiation of grazing pressure expressions and its applicable scenarios

High intensity grazing is considered as an important cause of grassland degradation. Numerous studies have explored effects of grazing activities on grassland ecosystems. Nevertheless, the research regarding grazing activity itself, especially the quantification methods and gradient division of grazing pressure, is relatively insufficient. Based on a total of 141 Chinese and English papers containing keywords such as 'grazing pressure', 'grazing intensity', and giving specific quantification methods and classification standards, we sorted out the definition, quantification methods, and grading standards of grazing pressure. The results showed that the definition of grazing pressure in current studies could be classified into two categories: considering the number of livestock carried in the current grassland ecosystem only from the perspective of the amount of grazing livestock; or considering the impacts or consequences on grassland ecosystems. Small-scale manipulative experiments mainly quantified and divided gra-zing pressure by controlling the number of livestock, grazing duration, grazing area, etc. Ecosystem responses to grazing activities were also converted by the above indicators, while the large-scale data spatialization method only considered number of livestock per unit area. The method of remote sensing inversion focused on ecosystem responses, that is, the impacts of grazing activities on grasslands, and it was difficult to separate the role of climatic factors. The quantitative standards of grazing pressure in different grassland types were quite different, even in the same grassland type, and such difference was directly related to grassland productivity.

The practice and thinking of the construction of the examination database of biochemistry

In the traditional biochemistry teaching process, the examination is usually done by the teacher after the course is finished. This test mode is currently the more “classic” mode, and students are generally accustomed to this method. However, there are bound to be certain defects in the teacher's independent examination, such as the choice of the content of the test questions is more arbitrary, and the knowledge scope of the assessment is relatively narrow. In addition, the traditional mode of separately marking and correcting questions will also result in different teachers' question-setting style, degree of depth, and different grading standards for teachers when grading. In the case of large fluctuations in test scores, it is difficult to test the teaching effect. In order to pursue a high pass rate, some teachers usually delineate the scope of the exam for students before the exam. Students often do not study seriously before the exam, which makes the students' exam scores and their understanding and mastery of knowledge points. Therefore, the course group is carrying out a computer-based examination question bank construction. It is designed to implement the separation of teaching and examination, and make the course examination more scientific, objective and accurate. At the same time, it can also provide conditions for the paperless examination of the course. Through teaching practice, the database can effectively improve the enthusiasm of students to study, and the teaching effect is good.

Experimental Investigation of Waste Rubber Admixtures in Concrete

In this experimental study, coarse aggregate is partially substituted with tyre rubber to examine the behavior and failure properties of rubberized concrete. Due to this waste's inability to biodegrade, there are significant fire, environmental, and health dangers. Concrete's characteristics could be greatly improved by using used tire rubber as a partial aggregate in a variety of ways. Currently, one of the world's biggest waste management issues is how to get rid of used tires. About 1.2 billion trash tires are produced annually worldwide. Therefore, efforts have been made to determine how discarded tires might be applied in construction projects. The purpose of this research is to look into the best way to use used rubber tires into concrete mix as coarse aggregate. Concrete is made by substituting 20%, 30%, and 40% of coarse aggregate with tires and the outcomes are compared to those of standard M25 grade concrete. The durability of newly laid and cured concrete were determined. The findings showed that rubberized concrete can be used to successfully counteract a loss of strength while maintaining the benefits of greater ductility. This suggests great prospects for uses in seismic zones, notably for structural columns. The main goal of this research is to identify an effective strategy for reusing rubber waste for improved ecological circumstances and the building sector.

Soil Nutrient Content Analysis of Newly-Increased Farmland in the Process of Land Consolidation In Shaanxi Province, China

The aim of this study is to analyze the characteristics of soil nutrient content of newly increased cultivated land in land consolidation, and identify the main factors affecting the productivity of newly increased cultivated land. The soil samples of 101 newly added cultivated land in northern, central and southern Shaanxi were collected, and their pH value, organic matter, total nitrogen, available phosphorus and available potassium contents were measured to analyze the soil nutrient status. The results indicated that the contents of soil organic matter, total nitrogen, available phosphorus and available potassium in the newly increased cultivated land were 0.21~23.63 g/kg, 0.20~8.27 g/kg, 2.34~34.16 mg/kg and 51~220 mg/kg, respectively. Compared with the nutrient grading standard of the second national soil survey, the content of soil nutrients in the newly increased cultivated land was relatively low, basically at the level of four to six. It was also revealed that Tte soil nutrient content of newly increased cultivated land in Shaanxi Province is greatly affected by the original land use types in northern Shaanxi and Guanzhong, and the soil nutrient difference in southern Shaanxi is mainly caused by the random changes among plots in the same region; The variance test showed that there were significant differences in soil pH organic matter and available potassium at 0.05 level, but no significant differences in soil total nitrogen and available phosphorus at 0.05 level. (3) It can be seen from the correlation analysis that among the nutrient indicators of the newly increased farmland in Shaanxi, pH organic matter has a significant negative correlation, and organic matter available potassium and available phosphorus available potassium have a very significant correlation. The correlation between soil nutrients in the newly increased farmland is weak, and the coordination between nutrients is poor. The low content of organic matter in soil is the main reason for low fertility. In the later stage of utilization, it is necessary to promote straw returning technology through the reasonable application of organic inorganic fertilizer and the application of soil testing formula fertilization technology, so as to finally realize the stable and high yield of newly added farmland. Bangladesh J. Bot. 51(4): 1017-1028, 2022 (December) Special

Validating the Reliability and Clinical Relevance of an Infraorbital Hollow Photonumeric Scale.

Infraorbital hollowing is a facial aesthetic issue for which a broad age range of patients seek treatment. Expanding treatment options for this region warrants the development of validated tools to objectively assess infraorbital hollow (IOH) severity before and after treatment. To validate a 4-point rating scale to assess depression of IOH, depression relative to the mid-pupillary line, and visibility of the lateral orbital rim. The IOH scale described herein was developed and subjected to live validation with a total of 73 patients representing the full range of IOH severities. Scale validation was performed by board-certified plastic surgeons and dermatologists (3 raters) over 2 rounds, 2 weeks apart. Intrarater and interrater reliabilities were used to demonstrate test-retest reliability as quantitated with percentage of agreement, weighted kappa statistic with 95% confidence interval (CI), and intraclass correlation coefficient with 95% CI. The clinical relevance of a 1-grade difference was evaluated by comparing rater assessments of 77 photo pairs with their previously determined designation as "clinically different" or "not clinically different." The IOH scale demonstrated substantial to near-perfect intrarater and interrater reliabilities when utilized by trained raters to assess a diverse group of live patients. Furthermore, clinically relevant differences between grades were established, and detection of a 1-point difference could be achieved by trained evaluators using the IOH scale. This highly reliable, clinically relevant, and validated IOH scale provides a user-friendly, standardized grading system to objectively evaluate and track changes in infraorbital hollowing in clinical practice and research.

Machine visual technology based steel corrosion evaluation and analysis of power transformation lines: A Zhejiang power grid case study

It can be seen that the corrosion failure of transmission and transformation equipment has increasingly restricted the safe operation of the Zhejiang power grid bottleneck problem. If effective anticorrosion measures are not taken promptly, transmission and transformation equipment serving in various sophisticated atmospheric environments will suffer serious corrosion damage in a relatively short period, which endangers the safe usage of transmission and transformation equipment and the security of grid operation. In this article, through the establishment of transmission and transformation steel components corrosion fracture mechanics model, a standard corrosion spectrum grading software based on DeepLabV3+ image segmentation technology is developed to determine the quantitative assessment method of corrosion damage and assess the corrosion status with safety degree of transmission and transformation equipment. According to the assessment results, the operation and maintenance units are guided to adopt differentiated corrosion maintenance and replacement strategies, so as to reduce corrosion safety hazards and reduce safety accidents and economic losses caused by corrosion, which is of great significance for the safe operation of power grids.

Thermodynamic foundations of the rational cutting modes choice under conditions of machining

Durability and tribological tests of standard grades of high-speed steels and experimental single-carbide hard alloys with modified cobalt binder, created on the basis of the standard VK8 grade, under conditions of friction and turning of structural steels 45 and 12Х18Н10Т were carried out. The experiments were carried out for various cutting speeds and friction in order to determine the dependence of the optimal modes from the point of view of reducing the wear rate for cutting materials with different structural and thermodynamic characteristics. It has been experimentally established that high-speed steels with high values of thermal entropy have greater wear resistance in comparison with low-entropy grades, and cutting (sliding) speeds corresponding to minimal wear rates are higher for them. For experimental hard alloys grades characterized by greater thermal entropy values of the binder lower wear rates at optimal cutting speeds compared to the base alloy were also recorded; the values of the optimal cutting speeds for these materials are also higher. Thus, high-entropy cutting materials allow machining at higher speeds, while reducing the wear intensity.

Carcass and meat quality traits in Brangus steers.

The quality grade system used in the United States to identify carcasses with superior eating satisfaction to consumers is based on the amount of marbling within the ribeye and the maturity of the carcass. However, the most important quality attribute for consumers is tenderness. The objective of this study was to investigate the phenotypic correlations between carcass and meat quality traits of strip loin steaks from Brangus steers, particularly the relation between the United States Department of Agriculture (USDA) quality grade and tenderness. Warner-Bratzler shear force (WBSF) values in this study averaged 5.10 ± 0.96 kg, slightly higher than the national average of 4.55 ± 1.14 kg. Average WBSF across all quality grades ranged from 4.90 to 5.27 kg with standard deviations ranging from 0.78 to 1.40 kg. In the present Brangus steer population, there was a weak negative (-0.13) but favorable correlation (P < 0.05) between marbling score and tenderness measured through WBSF. The USDA quality grade had a significant (P = 0.02) effect on WBSF. The WBSF least square means were significantly higher in the Select compared with the Choice¯, and Choiceº quality grades. The Choice⁺ and Prime quality grades were not significantly different from any quality grades regarding the WBSF. The standard quality grade did not have significantly different WBSF least square means from any other quality grade. The range of WBSF values was large, especially in the lower quality grade categories, indicating that there is considerable variation in tenderness, even within quality grade. The high level of variation in tenderness within USDA quality grades highlights the limitation of the USDA grading system to predict eating quality or tenderness.