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A better understanding of the molecular mechanisms in granulosa cells (GC) is warranted, during different follicular and luteal developmental stages in buffalo cows. We aimed to (I) study the expression of selected genes in GC during follicular and luteal phases, (II) evaluate correlations between GC gene expression and steroid concentrations {17-beta estradiol (E2) and progesterone (P4)} in follicular fluid (FF), and (III) study effect of ovarian status on follicular population as well as follicular size frequency. Ovaries were collected in pairs from buffaloes (n = 178). Ovaries bearing corpus luteum (CL) were subdivided into hemorrhagic, developing, mature, and albicans. Follicles from luteal groups were classified only into small ( 4 mm) and large (9-20 mm), while follicles from follicular groups were classified into three subgroups: small ( 4 mm), medium (5-8 mm), and large (9-20 mm). The FF and GC were collected for steroid concentrations measurement and gene expression, respectively. In the follicular phase, luteinizing hormone/choriogonadotropin receptor (LHCGR) and cytochrome P450 aromatase (CYP19) in small follicles decreased compared to medium ones. Large follicle showed an increase in LHCGR and CYP19 compared to medium ones. Follicle-stimulating hormone receptor (FSHR) decreased in large compared to medium size follicles. Proliferating cell nuclear antigen (PCNA) increased in small and large follicles. Meanwhile, anti-Mullerian hormone (AMH) and phospholipase A2 group III (PLA2G3) decreased in small and large follicles. The different stages of luteal phase had a profound impact on GC gene expression. There were strong (positive and/or negative) correlations between gene expression and steroid hormones. The different scenarios between expressed genes in GC and steroid concentrations are required for the proper growth and development of follicles and CL.

A total of 230 samples of four most public consumed fruits and vegetables, were collected from two wholesale Egyptian markets during 2015. The collected samples were subjected to analysis for 51 pesticide residues of organophosphates (OP’s) and pyrethroids (PY’s) groups. The standard method (QuEChERS) was followed to the analysis of samples applying LC-MS/MS determination. The obtained data showed that, 17.4% of samples had no detectable residues. Whereas, 82.6% had detectable pesticide residues of which 18.3% contaminated with levels above the MRL's and 64.3% (148 samples) had residues below the permissible limits. The highest contamination percentages were observed in grape followed by pepper, apple and tomato with percentages of 90%, 88.3%, 81.7% and 71.7% respectively of which 18%, 23.33%, 23.3% and 8.3% exceeded the permissible MRL's. The most frequent (OP’s) and (PY’s) are chlorpyrifos, cypermethrin, lambda cyhalothrin and diazinon. Risk assessment was evaluated via calculation of chronic and cumulative exposure for total of 17 residues of (OP’s) and (PY’s). The results indicated that no chronic health risk associated with consumption of studied commodities. The cumulative exposure values of (OP’s) pesticides was below 1 (0.059 for adults) in fruit samples and (0.108 for adults) in vegetable samples. Also, cumulative exposure values of (PY’s) pesticides were below 1 (0.012 for adults) in fruit samples and (0.017 for adults) in vegetable samples, indicateing no hazard to consumers due to presence of OP’s and PY’s residues in Egyptian fruits and vegetables.

The preliminary results of a prospective epidemiological study of the revised NIOSH lifting equation are presented. The baseline evaluations included assessment of lifting and lowering tasks with the revised NIOSH equation, as well as a questionnaire regarding personal variables. Subject follow-up was primarily accomplished through postal questionnaires, telephone interviews, and surveillance for workers' compensation claims for low-back disorders. The preliminary results reported are based on approximately 375 person-years of exposure; however, the follow-up period is still in progress. Important findings related to the usability of the revised NIOSH equation across several types of common exposures are also discussed.

A research project funded by the United States Postal Service surveyed letter carriers to evaluate three alternative satchel designs and the current satchel. The evaluation consisted of both field surveys and a laboratory study. Each satchel had positive and negative attributes. A two-pouch system (satchel C) that distributed weight on both sides of the body, proved to be the best alternative in the laboratory study. However, concerns regarding the use of satchel C for defense against a dog attack made its desirability questionable in the survey. The study showed that none of the four satchels was a universally accepted alternative. Recommendations are offered to improve the satched design. Relevance to industry The study examines four satchel designs that were evaluated for the US Postal Service. Similar techniques could be used to evaluate industrial designs for tools, equipment, clothing, or other work items.

Occupational biomechanics models deal with the evaluation of physical activities such as lifting of loads. This allows the user to determine the stresses imposed on the musculoskeletal system while holding or moving a load. These models are useful tools in estimating these stresses especially those imposed on the lumbar spine. dynamic biomechanical models, as opposed to static models require the displacement-time information to obtain the kinematics needed to estimate the kinetics of the motion. However, the collection of this displacement data is both tedious and can require expensive equipment. Simulation models on the other hand can provide an indirect means of performing the biomechanical analyses without having to collect the displacement-time data. A typical simulation model for 2-D lifting activities will be presented. The basis for this is the hypothesis that the body will perform the activity in such a manner so as to minimize the work done. Using this assumption an objective function was developed subject to a set of constraints. These constraints relate to the human movement, the physical workplace layout, and maintenance of balance. Using this model, it was possible to generate the lifting motion patterns, as well as the kinematics and kinetics of motion. The paper discusses the model development, the model output and the kinematics and kinetics of the simulation of the lifting action.

Preplacement strength testing is one of the most viable supplements to ergonomic job design. Previous studies have examined the roles of isometric, isokinetic, and some isoinertial measures in predicting lifting capacity. The goal of the current study was to examine the role of maximal lifting power in predicting maximum acceptable weight of lift (MAWL) relative to previously used isometric, isokinetic, and isoinertial tests. Twenty five male subjects participated in an experiment involving two isometric tests, peak isokinetic strength at velocities between 0.1 and 0.8 m. • sec.-1, and isoinertial lifting capacity and peak power measured on an incremental lifting machine. Peak isoinertial power was the measure most strongly correlated with MAWL, followed by isokinetic strength measured at 0.1 m. • sec.-1. Overall, the results support previous studies which have shown that dynamic strength measures are superior to static strength measures for the purposes of predicting maximum acceptable weights. Results of regression analyses and measures of prediction accuracy reported further support the use of dynamic measures.

Computerized human motion simulation allows generation of dynamic human motions on computers. Biomechanical stresses can be estimated using the motions generated on a computer without actually collecting joint coordinate data. A two-dimensional whole-body lifting simulation model is presented in this paper. The model assumes that humans perform lifting activities based on minimization of physical work, subject to various constraints. The simulation method contains three major computation units: trajectory formation unit, dynamics of motion unit, and nonlinear optimization unit. The trajectory formation unit generates smooth polynomials representing motion characteristics of human lifting. Kinematics and kinetics are calculated in the dynamics unit. Objective and constraint functions are evaluated in the optimization unit. Optimal motions are generated by minimizing the objective function, subject to the constraints. Computation methods of the three units and simulation results are presented.

Measurement of human strengths provides a database to aid in the design of jobs, work places, equipment, tools, and controls. Occasionally, strength measurements are also used in worker screening procedures. In the last few years, many new developments, particularly in the area of human dynamic strengths, have taken place. This position paper discusses these recent developments in human strengths and their applications. Unresolved research and application issues are also discussed.

For several decades manual materials handling has been a topic of interest in many fields of research. The reason for this interest is the devastating cost of and human suffering caused by injuries associated with MMH. Prevention and control of these injuries has been a concern shared by many researchers. In order to control the nature and extent of these injuries, limits must be established for MMH, especially lifting. This paper summarizes the variables affecting the ability to handle materials and the three basic approaches to determining capacities and limits for MMH: the biomechanical, the physiological, and the psychophysical approaches. The paper presents the various models developed in each of these approaches, together with a discussion of progress made and difficulties encountered in deriving capacity recommendations from each. Finally, the paper presents the latest recommendation on how these approaches can be integrated into a single comprehensive model for establishing lifting limits.

The purpose of this study was to describe and quantify measured hand forces during floor to knuckle lifting of various loads. Hand forces of five subjects were measured with a strain gauge apparatus for normal and fast speeds of lifting at 1, 4, and 8 l/min. The pattern of hand force over time exhibited peaks in force in the shape of a spike for all fast lifts, indicating that subjects did not lift smoothly. For normal speed of lift, only one of the five subjects executed some lifts smoothly, indicating that it may be possible to lift smoothly, but most lifters probably do not. Peaks of horizontal and vertical components of hand force were tabulated by speed of lift, frequency, and load.

Research efforts to establish manual materials handling (MMH) capabilities of individuals and populations have been conducted for many years. Most of the previous efforts have explored 'standard postures', utilizing two-handed, symmetric, sagittal plane MMH using unrestricted postures. Recognizing that many industrial MMH activities do not utilize 'standard postures', recent research projects have explored psychophysically determined MMH capacities in a variety of non-standard postures. Among the non-standard postures examined were: twisting while lifting or lowering, lifting and lowering from lying, sitting, kneeling, and squatting positions, and carrying loads under conditions of constricted ceiling heights. This paper presents the results of a series of previous research efforts at Texas Tech University. The results are presented in the form of population capabilities of both males and females for 99 MMH tasks using 'non-standard postures'. The data tables contain means and standard deviations of the data, as well as percentile distributions for the subject populations. Sample sizes for the experimental populations ranged from 45 to 50 subjects of each sex in the first three experiments to 20 subjects of each sex in the fourth set of experiments.

A study was conducted to assess the lifting capabilities of acclimatized individuals in hot environments. Six male subjects were selected for the study. The subjects were heat acclimatized for ten days prior to participation in the experiment. A psychophysical experiment was then carried out using three temperature levels (22, 27, and 32°C Wet Bulb Globe Temperature (WBGT), three frequencies of lift (0.1, 3 and 6 lifts/min), and one height of lift (floor to knuckle height). The results indicated that the maximum acceptable weights of lift selected by the subjects at 27°C WBGT were not significantly different from the weights selected at 22°C WBGT. On the other hand, the maximum acceptable weights selected at 32°C WBGT were reduced by approximately 13 percent.

Manual materials handling (MMH) is one of the most active research areas within occupational ergonomics. In response to substantial workplace losses, varied approaches to the design and evaluation of MMH tasks have been developed. The principles of mechanics, physiology and psychophysics have been used for over three decades to provide insight into the responses that the human body undergoes while handling materials, and form the basis of most of the analysis techniques. While considerable advances have been made, continued losses associated with MMH exposures indicate that further research is needed. Following a discussion of current practices, each of the panelists will provide their viewpoint on how we might advance our ability to design and evaluate MMH exposures.

A study was designed to determine whether training has an affect on the results of the isoinertial 6-foot incremental lift strength test. The study involved having five male and five female subjects participate in a two week training program in which the subjects trained on the isoinertial 6-foot incremental weight machine. The results of the study showed that the training protocol used in this study increased the mean of the results of the test by approximately 14% for male subjects and 23% for female subjects. These findings were statistically significant at the α = 0.05 level.

In the chemical, pharmaceutical, and paint manufacturing industries raw and finished materials are frequently shipped in cylindrical rigid containers instead of boxes. Psychophysical manual materials handling lifting capacity studies to date have not considered whether rigid container shape has an effect on maximum acceptable weight of lift. Two psychophysical studies were designed and conducted in order to answer this question. During the first experiment ten subjects lifted boxes with three different heights, at three different frequencies, and through three different lift ranges in order to establish a data base in which to compare the results of the second experiment. During the second experiment the same group of subjects lifted cylinders with three different heights at the same frequencies of lift and through the same lift ranges as the first experiment. The subjects adjusted the weight of the box until they felt they could safely lift that weight for eight hours. This weight was the maximum acceptable weight of lift (MAWL). The experimental design for both experiments was a 3 factor randomized complete block design with blocking on subjects. The dependent variables were oxygen consumption (VO2), MAWL, and Borg's rating of perceived exertion. The results indicated that when one designs a lifting task for a rigid container the shape of the rigid container, whether a cylinder or a box, does not need to be taken into account and that current psychophysical lifting capacity prediction models can be used to design cylinder lifting tasks.

This study examines the effects of velocity and starting position of pull on the configuration of the arm at the point at which peak maximal voluntary contraction (MVC) pull strenght is achived. Ten males performed 15 different isokinetic pulls each, defined by 5 starting positions of the arm in the saggital plane and 3 pull velocities for each position. Some restrictive conditions were applied to body posture and arm motions to facilitate biomechanical analyses of the results. All subjects were tested while seated. The results indicated that pull strength depended strongly on the starting position of the arm and velocity of pull. The angular configuration of the arm at peak strength position was unaffected by the starting position of the arm. This suggests that there may be an optimal arm configuration for dynamic (or even static) pull strength. For each tested velocity of pull, a different optimal configuration was found. Peak strengths attained have been explained by biomechanical principles, but the optimal arm configuration cannot yet be explained in the same way. The empirical relationships are, however, significant

Substernal goiter is an infrequent occurrence and is found in two to five per cent of all patients undergoing thyroid surgery. These lesions are well known to cause respiratory symptoms and alterations in phonation due to direct compression of airway structures. Infrequently, unilateral recurrent nerve palsy has been reported in patients with substernal goiter. We report a case of bilateral recurrent nerve palsy associated with multinodular substernal goiter in an 89-year-old female who presented in respiratory distress.

For approximately three decades, researchers have utilized psychophysics to develop guidelines (weights, forces and frequencies) for manual materials handling tasks. Early work by Stover Snook and his colleagues provided the foundations of the experimental methodologies that would be used by other researchers as well as design data that would be used by practitioners. Currently, there are extensive psychophysical data for designing a variety of materials handling tasks. The current state of psychophysical data will be examined, and the psychophysical approach will be compared to the biomechanical and physiological approaches to setting limits for materials handling tasks. The advantages and disadvantages of the psychophysical approach will be discussed, as will the research needs required to address the current limitations of the psychophysical approach.

An experiment was conducted to examine the role that maximal lifting power has in predicting maximum acceptable weight of lift (MAWL) for a frequency of one lift per 8 h. The secondary aim of the study was to compare the ability of power to predict MAWL to previously used measures of capacity including two measures of isometric strength, five measures of isokinetic strength, and isoinertial capacity on an incremental lifting test. Twenty-five male subjects volunteered to participate in the experiment. The isometric tests involved maximum voluntary contractions for composite lifting strength at vertical heights of 15 and 75 cm. Peak isokinetic strength was measured at velocities of 0.1, 0.2, 0.4, 0.6 and 0.8 m s-1 using a modified CYBEX II isokinetic dynamometer. Isoinertial lifting capacity was measured on the X-factor incremental lifting machine and peak power was measured on the incremental lifting machine by having subjects lift a 25 kg load as quickly as possible. The results indicate that peak isoinertial power is significantly correlated with MAWL, and this correlation was higher than any of the correlations between the other predictor variables and MAWL. The relationships between the isokinetic strength measures and MAWL were stronger than the relationships between the isometric measures and MAWL. Overall, the results suggest that tests used to predict MAWL should be dynamic rather than static.

Manual materials handling (MMH) account for approximately $15.0 billion of injuries cost in the United States alone. Because of the need to establish manual handling guidelines, different approaches to achieve this goal were pursued. Such approaches are based on biomechanics, work physiology, and psychophysics. In order to better understand the MMH system's behavior, models were developed. These models can be divided into biomechanical models, physiological models, psychophysically based capacity models, safe load handling models, and simulation models. This paper will present a sample of these models and discusses their advantages and disadvantages.

A field study was conducted to compare four satchels designed for the purposes of manually carrying and delivering mail. The satchels differed primarily in the presence/absence of a waist belt, the number and design of the shoulder strap(s) and the number of pouches. The evaluation consisted of questionnaires and interviews of slightly more than 300 letter carriers employed by the United States Postal Service. The questionnaires focused on 10 main areas of interest; ease of adjustability and handling, comfort, suitability and durability of materials, anthropometric applications, impact on other activities, ease of motion in retrieving mail, ease of motion in carrying the satchel, versatility of use in diverse climates, protection of mail from damage due to rain and snow, and defense against dog attacks. The primary conclusion was that the satchel with two shoulder straps and two pouches, which results in more symmetric loading than the other satchels, is the most desirable of the satchels tested. However, there are problems with the satchel that need to be addressed, such as concerns about the use of the satchel for defense from dog attacks.

A biomechanical investigation of four satchels designed for the purposes of manually carrying and delivering mail was conducted. Twenty United States Postal Service carriers participated in the study. The satchels differed primarily in the presence/absence of a waist belt, the number and design of the shoulder straps, and the number of pouches. The biomechanical analyses were comprised of postural (shoulder and hip) deviation measurements, estimated compressive forces at the l 5 s 1 joint, soft tissue pressure on the shoulder, spinal torsion during mail retrieval, force distribution between the feet, and an anthropometric evaluation. The results indicated that a satchel with two shoulder straps and two pouches was more desirable than the single-pouch satchels from a biomechanics standpoint.

Between 1983 and 1990, 32 consecutive patients had 35 thru-knee amputations for ischemia causing infection or gangrene of the lower leg. Twenty-seven patients were nonambulatory, five had limited mobility, and none were considered to be candidates for rehabilitation with a prosthesis after surgery. The average age was 73 years. Thirty-day hospital mortality was 3 per cent. The incidence of complications was low, and healing was achieved in 97 per cent of survivors. One patients required revision to an above-knee amputation. Average postoperative hospital stay was 8.7 days. It is concluded from this study that thru-knee amputation is the treatment of choice in patients with nonsalvageable ischemic legs and in whom ambulation is not planned after operation.

A workplace is the place which contains the space, tools, and equipment where workers perform the functions and tasks of their jobs. The area of workplace design is a rich field with many facets. Historically, the study of workplace design has developed out of many different disciplines, including industrial engineering, human factors, and industrial psychology. Generally, a good workplace design is one where a worker can easily change positions to relieve the stresses and pressures of a posture while still performing job tasks efficiently and easily. Specific considerations for the design of the workplace include the type of workplace (sitting vs standing), work envelopes, and postural concerns are discussed. Finally, guidelines for the evaluation of existing and proposed workplaces are presented.

A biomechanical and work physiology study in underground mining was conducted. Anthropometric, isometric strength, and physical work capacity (PWC) data were collected. Female miners were significantly heavier and larger in circumferential measurements than comparison groups (males did not differ from other groups in terms of anthropometry). Underground miners were significantly stronger than comparison groups, and were rated low in terms of PWC. Energy expenditure measurements were made on 35 underground mining tasks; the majority falling under the categories of moderate to heavy work. Postural stresses were assessed using a modified version of the Ovako Working Posture Analysis System (OWAS; developed by Karhu, et al. 1977). Several tasks appeared to cause substantial postural stress. Postural stress was correlated significantly with physiological demand. Recommendations based on the findings of the study included: increased use of powered equipment in place of manual labor for several tasks, modifications to existing equipment designs, and modifications to the work clothing design standards developed by Caddel, et al. (1981) for low coal miners.

The application of safety concepts in the industrial environment has gained momentum especially in the area of manual materials handling. Manual materials handling is a priority concern due to the high percentage of industrial injuries that result from such tasks. Industry needs an approach to establish human lifting capability in order to properly design jobs within these capacities. With the assumption that there is a relationship between an individual's lifting capacity and his/her injury potential, methods for determining maximum permissable weight of lift are reviewed. With these accomplishments in mind, the future work to be accomplished by the ergonomics community is forecast.

A literature survey on recommendations for the maximum weight of the load and work loads is presented. Three different criteria are reviewed to determine the "safe" weight and permissible work loads that a person can lift. These are biomechanical, psychophysical, and metabolic/heart rate. A comparison of recommended load limits based on each of the three criteria is presented. Maximum weight of the load and work loads based on the three criteria are also compared. The comparison shows that (1) the recommendations based on a given criterion are not in agreement, (2) the maximum permissible weights of the load based on psychophysical studies are lower than those based on biomechanical criteria, and (3) the psychophysical fatigue criteria, as compared to physiological fatigue criteria, will result in greater work loads at higher frequencies of lifting. Load-pace tradeoff and effects of lifting technique and location of load on acceptable work loads are also discussed.

Endurance is the ability to sustain or persist in an activity continuously, This paper describes an attempt to develop a satisfactory means of predicting in advance the endurance time limit of an individual engaged in a physical task of alternating workload nature. Under moderate to heavy muscular work the endurance of a worker is related to the rate of energy output required to perform the task. Further, it has also been observed that even under a fixed workload demand, the energy output level of the worker tends to increase gradually with time. The above two criteria were taken into consideration in developing the predictive models described here. A series of experiments, with subjects walking on motor-driven treadmill while being monitored for oxygen intake and other physiological parameters, was conducted to obtain necessary data for the models and to verify the accuracy of the models. These models, it is felt, have considerable practical value with possible applications in industry, the mili...

Models related to lifting activities have been classified and reviewed. Predictive models are grouped under psychophysical capacity modeling, physiological energy requirement modeling, and biomechanical stress modeling. Within each group, the models have been compared and evaluated. In addition, psychophysical and physiological model groups have been compared.

The transfusion service of a regional referral medical center issues a monthly blood and component wastage report to the Hospital Transfusion Committee. The report includes the amount and type of units wasted, who is responsible, and the cost incurred by the wastage. The individuals responsible for wastage include physicians, nurses, and laboratory personnel. Physicians are responsible for most wastage, principally by failing to administer thawed or pooled blood products. The Hospital Transfusion Committee initiated a wastage-reduction program that included a letter to physicians indicating the patient's name and the type of blood and/or components that the addressed physicians was responsible for wasting. Simple corrective actions results in a 73 percent reduction in our blood and component wastage. Monitoring of blood and component wastage should be routine quality assurance function of the Hospital Transfusion Committee.