Number Of Stairs Research Articles

Comparative analysis of two evacuation simulation tools when applied to high-rise residential buildings

Currently there are numerous emergency evacuation simulation tools with varying levels of sophistication and differing capabilities. It is expected that investigating the same scenarios using different tools might not give the same outcome. This paper illustrates how a microscopic agent-based modelling tool (Pathfinder) and a macroscopic flow-based modelling tool (Evacuationz) can be setup to investigate high-rise residential building evacuations in comparable ways by varying configuration parameters. Both tools represent individual agents with associated characteristics (e.g., walking speed and pre-evacuation delay). These are varied in the scenarios examined to stress-test the designs or explore the impact of design/procedural changes.The two tools differ in how they deal with the building geometry and therefore have different algorithms to manage evacuee movement. In this work, assumed performance parameters (e.g., travel speeds, spacing, etc.) have been calibrated to better align the conditions represented in the tools and the outcomes produced across the scenarios examined. This then allows the tools to function at their respective levels of sophistication and granularity (providing different perspectives on performance) but adopt a more equivalent performance baseline given the calibration effort.The use of two tools increased confidence in the predictions, and also allowed for an examination of a wider range of scenario conditions such as number of stairs, stair width, and building size, given the different computational expense associated with the tools.

Evaluating the Compliance of Saveh Primary Healthcare Centers with World Health Organization's Age-Friendly Standards

Background: Since primary healthcare is a significant link in promoting and maintaining the health of the elderly, evaluating age-friendliness of service provision system is of great importance in ensuring the health of the elderly. The purpose of this study is to evaluate the state of primary healthcare centers’ compliance with the standards of age-friendliness in Saveh city.
 Methods: This was a cross-sectional and descriptive study conducted on May and June 2022, in Saveh city, Markazi Province in Iran. The statistical population of the research included 33 primary healthcare centers selected by the census method and based on World Health Organization’s checklist regarding age-friendly primary healthcare centers (2008); they were examined by observation. After translating the checklist, its face validity, content validity, and reliability were reviewed and approved by 13 experts in the fields of health policy, health education and promotion, the elderly's health, occupational health engineering, and healthcare. Data analysis was done using descriptive statistical tests, one-way analysis of variance, Kolmogorov-Smirnov test, Tukey's post hoc test, and SPSS 16 software.
 Results: Regarding the psychometric analysis of checklist, based on the experts' opinions, the content validity ratio and content validity index were calculated and except for 8 items, all items scored higher than 0.54 and 0.79. In order to check the reliability, the research tool was provided to 2 observers. By calculating the Kappa coefficient, the agreement between the 2 observers was above 0.6, which indicates the validity of the checklist. This study showed that comprehensive health centers and their affiliated units had a 57.6% access to public transportation and 72.7% access to stairs at the front entrance. The entry was 100% free from obstacles, access to parking was 42.4%, access to public telephones, 18.2%, to a reception counter near the entrance restrooms, 42.4%, to waiting room, 78.8%, to a dining area, 42.4%, to stairs, 9.1%, to corridor, 87.9%, compliance with guiding signs, 66/7%, visibility of the signs, 72.7%, and personnel identification was 42.4%. Also, based on the analysis of variance, a statistically significant difference was obtained between the type of centers (urban and rural) and friendliness towards the elderly (p < 0.05).
 Conclusion: Primary healthcare centers of Saveh city did not have an acceptable compliance with the standards of age-friendly centers. The main issues are the number of stairs and the lack of alternatives (ramps and elevators) for people with mobility problems, the lack of facilities such as public telephones, and the inadequacy of guiding signs and personnel identification to identify employees. The government should strengthen and improve primary healthcare centers for the elderly and facilitate geographical access to these centers, considering the important role of these centers in the health of the elderly.

Numerical study of a double-stair-shaped dielectrophoresis channel for continuous on-chip cell separation and lysis using finite element method

Prognostication of numerous chronic diseases are in need of identifying circulating tumor cells (CTCs), afterwards, separating and reviving contaminated samples are required. Conventional methods of separating blood cells, namely cytometry or magnetically activated cell sorting, in many cases lose their functionality, or efficiency under different conditions. Hence microfluidic methods of separation have been implemented. Herein, an innovative integrated double stair-shaped microchannel is designed and optimized, capable of ‘separation’, and ‘chemical lysis’ simultaneously in which the lysis reagent concentration can be controlled to tune the lysis intensity. The method of insulator-based dielectrophoresis (iDEP), which is the main physics in this device, is utilized yielding maximum separation. Pivotal features of the applied voltage, the voltage difference, the angles and the number of stairs, and the width of the throat in the microchannel have been numerically explored in order to optimize the channel in terms of separation and the lysis buffer concentration. The overall state of optimum case for the voltage difference (ΔV) of 10 owns the following features: the number of stairs is 2, the angle of stairs is 110°, the width of throat is 140 μm, and the inlet voltages are 30 V and 40 V. Also, the overall state of optimum cases for delta possess the following features: the number of stairs is 2, the angle of stairs is 110°, the width of throat is 140 μm, and the inlet voltages are 30 V and 35 V.

Number of Stairs at Home is Associated with Discharge to Post-Acute Care Facility Following Total Knee Arthroplasty

Background Discharge to post-acute care facility (PACF) carries significant cost and quality burdens to patients undergoing total knee arthroplasty (TKA). In a recent study of pre-bundled payment model patients, the number of stairs (NOS) at home did not influence discharge to PACF for total hip arthroplasty. However, no study has yet examined NOS as it relates to discharge destination after TKA. In a large metropolitan market, it is not uncommon to have several flights of stairs leading to a home. We hypothesize that the number of unavoidable stairs to enter a home is a significant risk factor for discharge to PACF. Methods We reviewed 557 patients who underwent elective TKA at a single urban academic medical center between November 2011 and October 2014. Demographic data as well as NOS, ASA score, RAPT score, LOS, operative time, and tranexamic acid use were collected. T-tests, ANOVA, and Kruskal-Wallis analysis were conducted followed by a logistic regression to compare associations of factors to discharge to PACF. Results Of the 540 patients included in analysis, 193 (35.7%) were discharged home and 347 (64.3%) were discharged to a PACF. NOS (OR=1.457, p<0.001) and increased age (OR=1.057, p<0.001) were found to be significant risk factors for discharge to PACF while female sex (OR=0.57, p=0.013) and higher RAPT scores (OR=0.83, p=0.004) were protective against discharge to PACF. Conclusion With the conclusion of recent bundled payment programs, financial carrots may disappear, though it is likely that sticks will remain. Therefore, all risk factors must be identified and addressed. We found, in a pre-bundled payments era, that stairs is a risk factor for non-home discharge in a metropolitan population, and we confirmed other known risk factors of older age, higher ASA score, and lower RAPT score.

Number of Stairs at Home Does Not Influence Discharge Disposition following Elective Total Hip Arthroplasty

Background Pragmatic challenges of the patient’s home environment, specifically the number of stairs (NOS) required to enter or navigate a patient’s home may influence discharge destination (DD) and length of stay (LOS) following primary Total Hip Arthroplasty (THA). Questions/purposes This study investigates whether the NOS at home predicts discharge to a post-acute-care-facility (PACF) following THA. Methods 548 consecutive THA patients at a single urban arthroplasty center between 2011-2014 were reviewed. Patient factors including age, sex, BMI, length of stay, operative time, Anesthesia Score Assessment (ASA), the Risk-Assessment-and-Prediction-Tool (RAPT) and NOS stairs were analyzed. Logistic regression was performed to identify predictors for disposition to PACF. Groups were cohorted by number of stairs, and incidence of PACF discharge was determined. Results 238 (43.4%) patients were discharged to PACF. The NOS at home had no impact on discharge to PACF (OR 1.02, 95% CI .993-1.04, p=0.209). Older age (OR 1.09, 95% 1.07-1.10, p<0.0001), LOS (OR 1.23, 95% 1.08-1.39, p=0.001), higher ASA (OR 1.74, 95% 1.19-2.53, p=0.004), and lower RAPT score (OR 0.0.865, 95% 0.781-0.958, p=0.005) were significant predictors for disposition to PACF (p<0.005). Female sex was protective in discharge to PACF (OR 0.391, 95% 0.260-0.587, p<0.0001). The incidence of PACF discharge was similar between groups of unavoidable stairs at home. Conclusion The NOS at home did not influence discharge destination following THA. This retrospective study helps discharge planning and in setting expectations for patients undergoing THA by supporting a home discharge in the setting of unavoidable stairs.

영국 주거공간의 피난안전 기준에 관한 연구

This paper aims to investigate fire safety and the means of escape in the realm of interior space, particularly in dwellinghouses in order to build the standard of institutional regulations and design plans in Korea. For this, this paper examines the current regulations on the means of escape in the dwelling space in the UK. Fires in residential spaces account for 25% of the country’s total fires and over 40% of all casualties. As a part of methods to reduce casualties, a re-examination of the fire safety is necessary, and the social safety net must be established through proposals for improvement of the standards of the escape route in dwellings. The documentation of fire safety, such as Approved Document B, Building Act and Fire safety in purpose-built blocks of flats provide a specific regulation on fire safety in dwellings in the UK. The standards were classified into housing and apartments. Fire alarm, the details of horizontal and vertical escape routes according to the height of the building and the number of stairs were investigated. Therefore, this paper will contribute to supporting the Korean escape route used as a framework that can improve the current regulation of the fire safety and solve various problems that occur in the interior construction on fires and regulations in Korea.

Do Stairs Inhibit Seniors Who Live on Upper Floors From Going Out?

Walk-up buildings are common in China today since they were almost the only type of residential buildings constructed from the 1950s to the 1990s. This study examined how a vertical mobility obstacle, that is, mandatory stair climbing in walk-up residential buildings, may impact whether seniors go outdoors. We collected and examined 1,608 valid data records from 64 Chinese senior participants in Shanghai wearing Fitbit HR wristbands that tracked their mobility and physical activity for 31 consecutive days. Multilevel mixed-effects logistic regressions were performed on the binary leaving-home-or-not probability by the level of vertical obstacles controlled for physical-demographic factors, socioeconomic factors, outdoor activity habits, and weather. Our observations revealed that each floor above ground level reduced the likelihood of outdoor trips by approximately one third per floor. After controlling for the physical, demographic, and socioeconomic factors of the participants as well as weather and holidays, we found that significantly fewer going-out incidents were also associated with more frequent outdoor activities within the community, especially in paved areas, but no associations were observed with self-reported visit frequencies to green spaces, senior centers within the community, or other places outside the community. This study offered the in situ observation that seniors' probability of leaving their homes is correlated with the degree of vertical circulation as a mobility barrier (i.e., the number of stairs between their living space and access to the outdoors), which may impact policy making for regulations concerning elevators in residential codes and renovations.

What psychological and physical changes predict patients’ attainment of personally meaningful goals six months following a CBT based pain management intervention?

Purpose: To examine the influence of demographic measures, and changes in physical ability, pain, self-efficacy and emotional distress on Goal Attainment Scaling (GAS) scores, after a 15-day CBT based pain management programme.Method: Chronic pain patients (N = 257) were referred; 225 (88%) completed the programme and were invited for follow up six months later. One hundred and sixty-two (63%), (mean age 47.7, 71% female) completed the reassessment procedures. GAS scores (which were also repeated at the end the programme), an 11-point Pain Numerical Rating Scale, Pain Self-Efficacy Questionnaire, Hospital Anxiety and Depression Scale, distance walked in 5 mins, number of sit/stand repetitions in 1 min and number of stairs climbed in 1 min were measured on the first day and six months following the programme.Results: At six months post discharge, changes in goal attainment, physical measures, pain intensity, depression and self-efficacy were observed. Hierarchical regression showed change in GAS was predicted by improvement in walking tolerance and self-efficacy.Conclusions: The achievement of personally important goals was most significantly associated with change in walking ability and self-efficacy, while controlling for the influence of change in pain.Implications for RehabilitationChronic pain can reduce psychological and physical functioning, leading to a reduction in meaningful activities.Achievement of personally important activities as measured by Goal Attainment Scaling can be a more sensitive measure of programme outcome than that captured by many other standard measures.Self-efficacy is an important predictor of attainment of patient preferred goals following a CBT based pain management programme, and could be emphasized during treatment along with improved walking ability, to enhance patients’ goal achievement.

Effect of One- vs. Two-Stair Climb Training on Sprint Power

Although running stairs is often used in sport conditioning programs, at present, little research has examined the effect of stair climb training on sprint power. The purpose of this study was to investigate the effects of running stairs either 1 stair (1S) or 2 stairs (2S) at a time on power. Fourteen male college track and field athletes were randomized into 3 groups; 1S, 2S, or control (C). All groups were pre- and posttested for 1S, 2S, and 40-m sprint split times. The 1S and 2S groups trained twice per week, for 4 weeks, performing 10 sets of climbing 68 total stairs with 2.5-minute rest between trials. The greatest power values (W) from pre- and poststairs and sprint splits were used for statistical analyses. There was a significant (p < 0.05) interaction of group × time for stair climb. The 1S group increased power for the 1S test (pre-1,492.89 ± 123.76; post-1,647.41 ± 73.65) with no change in the 2S test (pre-2,428.80 ± 414.81; post-2,430.32 ± 154.90), whereas the 2S group increased power for the 2S test (pre-2,343.73 ± 317.50; post-2,646.17 ± 305.43) with no change in the 1S test (pre-1,516.69 ± 210.64; post-1,529.38 ± 236.69). The C group showed no change in either stair test (1S: pre-1,403.35 ± 238.67, post-1,384.38 ± 153.32; 2S: pre-2,285.93 ± 345.03, post-2,261.85 ± 356.88). There were no significant interactions or main effects for any sprint split power (40 m: pre-5,337.13 ± 611.86, post-5,318.68 ± 586.24).Therefore, stair climb training either 1 or 2 at a time did not affect 40-m sprint split power but increased power for the specific stair training type. Coaches should choose the number of stairs that are similar in time and power output to sprint training.

Ben-Hur Staircase Climbs

SummaryHow many ways may one climb an even number of stairs so that left and right legs are exercised equally, that is, both legs take the same number of strides, take the same number of total stairs, and take strides of either 1 or 2 stairs at a time? We characterize the solution with a difference equation and find its generating function.

Mesenchymal stem cell therapy for knee osteoarthritis. Preliminary report of four patients

Osteoarthritis (OA) is a cartilage degenerative process, involving the immune system, producing local inflammatory reactions, with production of pro-inflammatory cytokines and metalloproteinases. No treatment is still available to improve or reverse the process. Stem cell therapy opened new horizons for treatment of many incurable diseases. Mesenchymal stem cells (MSCs) due to their multi-lineage potential, immunosuppressive activities, limited immunogenicity and relative ease of growth in culture, have attracted attentions for clinical use. The aim of this study was to examine whether MSC transplantation could reverse the OA process in the knee joint. The project was approved by the Tehran University of Medical Sciences Research Committee and Ethical Committee. Four patients with knee osteoarthritis were selected for the study. They were aged 55, 57, 65 and 54 years, and had moderate to severe knee OA. After their signed written consent, 30 mL of bone marrow were taken and cultured for MSC growth. After having enough MSCs in culture (4-5 weeks) and taking in consideration all safety measures, cells were injected in one knee of each patient. The walking time for the pain to appear improved for three patients and remained unchanged for one. The number of stairs they could climb and the pain on visual analog scale improved for all of them. On physical examination, the improvement was mainly for crepitus. It was minor for the improvement of the range of motion. Results were encouraging, but not excellent. Improvement of the technique may improve the results.

Efectividad de la acupuntura en el tratamiento del dolor en la artrosis de rodilla

To determine the effectiveness of acupuncture in controlling pain from arthritis of the knee. Systematic review. MedLine, the Cochrane Library. Of the 9 studies located, only 4 met the inclusion criteria. All were controlled, randomized clinical trials that studied the effect of acupuncture only in the knee joint. Primary outcome variables were intensity of pain, overall measure (general improvement, proportion of patients who recovered, subjective improvement in symptoms) and functional status. As secondary outcome measures we used objective physiological measures (range of knee movement, muscle strength, time needed to walk a certain distance, time needed to climb a certain number of stairs), general health status, and other information such as medication needed and side effects. There was moderately strong evidence that acupuncture was more effective in treating knee joint pain than no treatment. The difference can be explained by its marked placebo effect. There is currently insufficient evidence to recommend acupuncture as a treatment for pain from osteoarthritis of the knee. Additional, better designed studies are needed to determine the actual role of acupuncture in this disease.

Challenging the Role of pH in Skeletal Muscle Fatigue

Muscle fatigue is frequently defined as a temporary loss in force- or torque-generating ability because of recent, repetitive muscle contraction (1). The development of this temporary loss of force is a complex process and results from the failure of a number of processes, including motor unit recruitment and firing rate, chemical transmission across the neuromuscular junction, propagation of the action potential along the muscle membrane and T tubules, Ca2+ release from the sarcoplasmic reticulum (SR), Ca2+ binding to troponin C, and cross-bridge cycling (for detailed reviews, see Bigland-Ritchie and Woods(1), McLester(2), and Favero(3)). Muscle fatigue may limit the time a person can stand, the distance a person can ambulate, or the number of stairs a person can ascend or descend. In practical terms, however, we cannot know what actually leads to a decline in function for a given patient. For a phenomenon that may have profound clinical implications, muscle fatigue often receives inadequate attention in physiology textbooks, many of which contain a page or less of information on the entire topic (4-8). In addition, many textbooks report that muscle fatigue is mainly the result of a decrease in pH within the muscle cell due to a rise in hydrogen ion concentration ([H+]) resulting from anaerobic metabolism and the accumulation of lactic acid (6-8). Recent literature, however, contradicts this assertion (9-10). The purpose of this update, therefore, is to provide a brief review of the role of pH in the development of muscle fatigue.

Duration and frequency of every day activities in total hip patients

Little knowledge about frequency and duration of daily activities in patients after total hip arthroplasty is available. Such information is required for the definition of realistic load collectives for pre-clinical testing of prostheses. It could also be helpful for the quantitative evaluation of surgery outcome with different prosthesis types. The purpose of this study was to develop and apply a system for the determination of frequency and duration of patient activities in their habitual environment and to compare the results to a clinical outcome score (Harris hip score). A portable activity monitoring system (weight 1.6 kg including batteries) was designed using a Palmtop computer, 2 inclination sensors for the thigh and calf and one goniometer positioned at the knee joint. An algorithm was developed to identify frequency and duration of the activities lying, sitting, standing, walking and stair climbing from the signals of the 3 sensors. 42 patients participated in the study and were equipped with the system in the morning at their home. Datasets of 31 patients (age 62.5±11.5 y) covered more than 6 h (9.8±1.6 h) and were included in the analysis. Prosthesis specific data as well as the Harris hip score were collected. The most frequent patient activity was sitting (44.3% of the time), followed by standing (24.5%), walking (10.2%), lying (5.8%) and stair climbing (0.4%). The median number of steps/stairs was 6048/164. The number of step cycles representing one year in vivo use should, consequently, be increaesed to 1.1 million. The Harris hip score (91.4±9.8) correlated significantly with the number of stairs ( r 2=0.26, p=0.003) and showed a positive tendency with the number of steps per day. No differences in activity levels between prosthesis specific factors were found.

A semi-analytical method of finding an optimum cutter path for face milling 3-sided convex surfaces

This paper introduces a modified staircase method for optimizing the cutter path for face milling convex polygonal surfaces. The strategy for optimal face milling of flat triangular polygons is explained. Analytical equations have been developed to calculate individual segments along the cutter path leading to a comprehensive equation for calculating the total cutter path. The method does not require an iterative approach to calculate the length of cutter path and produces better results when compared with other published methods using a similar illustrative example. The findings indicate that the optimal path is likely to be obtained when the number of stairs is minimum which happens when the stairs are generated parallel to the largest edge. However, it appears unlikely that a single equation is possible that will give the global optimum path. In conclusion, the strategy developed can also be used for finding optimum cutter path for n -sided polygonal surfaces.

Babywalker-related injuries continue despite warning labels and public education.

To describe the epidemiology of babywalker-related injuries to children treated in a pediatric emergency department despite current prevention efforts, and to investigate the beliefs of parents regarding babywalker use. A descriptive study of a consecutive series of patients. The emergency department of a large, academic children's hospital. Children treated for babywalker-related injuries during the 3-year period of March 1993 through February 1996. There were 271 children treated for babywalker-related injuries. The mean age was 9.2 months, and 62% of patients were boys. Ninety-six percent of children were injured when they fell down stairs in their babywalker. The number of stairs that a child fell down was significantly associated with skull fracture and admission to the hospital, and a fall down more than 10 stairs had a relative risk (RR) of skull fracture = 3.28 (95% confidence interval, 1.35 < RR < 7.98). There were 159 children with contusions/abrasions (58.6%), 35 concussions/head injuries (12. 9%), 33 lacerations (12.2%), 26 skull fractures (9.6%), 9 epistaxis (3.3%), 4 nonskull fractures (1.5%), 4 avulsed teeth (1.5%), and 1 burn (0.4%). Three of the skull fractures were depressed, and three also had accompanying intracranial hemorrhage. Ten patients (3.7%) were admitted to the hospital, and all had skull fractures resulting from falls down stairs. Supervision was present in 78% of cases, including supervision by an adult in 69% of cases. Forty-five percent of families kept the walker, and 32% used the walker again for the study patient or another child after the injury episode. Fifty-nine percent of parents acknowledged that they were aware of the potential dangers of babywalkers before the injury event. Fifty-six percent of parents favored a national ban on the sale of walkers, and 20% were opposed. Despite the currently used prevention strategies, including adult supervision, warning labels, care giver education programs, and stairway gates, serious injuries associated with babywalkers continue to occur to young children. The US Consumer Product Safety Commission should promulgate a rule, similar to the voluntary standard adopted in Canada, regarding design requirements for babywalkers that will prevent their passage through household doorways at the head of stairs. The manufacture and sale of mobile babywalkers that do not meet this new standard should be banned in the US. A recall or trade-in campaign should be conducted nationally to decrease the number of existing babywalkers.

Determinants of Achievement in Stair Climbing as an Exercise Test

Physicians routinely discuss pulmonary function and its impact on prognosis or operative risk. Although many studies have related various measures of pulmonary function to postoperative outcome, there has been no study designed to determine which of the spirometric measures of pulmonary function tests reflects the actual abstract idea of pure pulmonary function. A homogeneous population of 70 male patients was subjected to pulmonary function tests and a simple stair climb. Measures of pulmonary function (including FEV1, FEV1%, FVC, FVC%, and MVV%) were factor analyzed in a measurement model of pulmonary function to obtain reliability and validity estimates in predicting performance on a simple stair-climb test. The analysis revealed several interesting aspects concerning the relative importance of the various spirometric measures of pulmonary function tests. The validity estimates of the pulmonary function measures were as follows: FEV1% = 0.917; FEV1 = 0.886; MVV% = 0.769; FVC% = 0.715; FVC = 0.694. Analysis indicates that the FEV1% was the single best spirometric indicator of pulmonary function when predicting the physiologic outcome (followed closely by the FEV1). In addition, the various spirometric measures of pulmonary function were not equally valid nor interchangeable in such analysis. Although the number of stairs climbed correlates well with pulmonary function (r = 0.626), the coefficient of non-determination (i.e., 1-r2) suggests that about 61% of the performance on the stair climb may be explained by other parameters (i.e., cardiac function, determination, altitude, etc.).

Predicting behavioral outcomes with two psychological assessment methods in an outpatient pain management program

Abstract In research with pain patients, the determination of psychological variables that can predict physiological gains would be helpful for practitioners doing assessments on pain patients. The present study used the Millon Behavioral Health Inventory (MBHI) and the Minnesota Multiphasic Personality Inventory (MMPI) to assess whether gains in time sitting, time standing, number of stairs climbed, time on a treadmill, treadmill speed, grip strength in both hands, and a composite score of these variables could be successfully predicted for patients at a 20-day outpatient multidisciplinary pain rehabilitation program. Discriminant analyses demonstrated that both the MBHI and the MMPI were successful in this prediction. Advantages for using the two instruments singly and together in assessment procedures and suggestions for future research are made.

Work inequalities for plastic fracturing materials

Studied are second-order work inequalities for stability of plastic strain increments and fracturing stress decrements. It is found that the positiveness of the second-order work during small loading cycles does not necessarily require normality; it also allows non-normal plastic strains or fracturing relaxations which do no work, as well as non-normal ones which always do non-negative work. The latter ones include plastic strains and fracturing relaxations that are tangential to the loading surface. It is shown that the endochronic theory follows from Drucker's postulate by the same arguments as classical plasticity. The endochronic loading surface has the significance of separating the directions for which Drucker's postulate is satisfied from those for which it is not, whereas in classical plasticity it separates the stress increment directions for which the plastic strain increment vector points outside the loading surface from those for which it would point inward. The incremental linearity of classical plasticity is shown to be a tacitly implied hypothesis which does not follow from Drucker's postulate and the existence of the loading surface. Various incrementally nonlinear stress-strain relations satisfying Drucker's postulate, both such that do and do not obey normality, are demonstrated.Furthermore, it is found that for frictional materials there exists, in addition to Drucker's (or Il'yushin's) postulate, another inequality that also suffices for stability and reflects the fact that a release of elastic energy blocked by friction or by resistance to fracturing due to compression cannot cause instability. This enlarges the domain of all stable stress increment vectors from a halfspace to a reentrant wedge. The corresponding plastic strain increment vectors have no unique direction and occupy a fan, one boundary of which is the normal vector. Dependence of the second-order work in loading cycle upon the angle between the strain increment vector and the normal is useful for comparing various theories. For the incrementally linear vertex model one needs to introduce at the tangential direction a discontinuity in this dependence.Finally, some related questions of uniqueness or continuity of response are discussed, particularly for the case of a staircase path in strain space approaching a straight path as the number of stairs tends to infinity. For endochronic theory as well as some vertex models and for plasticity with a corner on the loading surface, the response to the staircase path in the limit does not approach the response to the straight path. Although this is not physically unreasonable, it is nevertheless possible to slightly adjust the definition of intrinsic time so that continuity (uniqueness) is achieved.

Effect of circuit exercise training on physical fitness of alcoholic patients.

A group of patients with chronic alcoholism who participated in a circuit training exercise program were compared on a stair climbing task to a group of patients who did not participate in the program. After three weeks, the patients in the exercise group had gained significantly in the number of stairs which they could climb when compared to the patients in the nonexercise group. The time required to return to the heart rate before stair climbing was significantly shorter for exercising patients than for nonexercising patients. The circuit training exercise program, therefore, appears to be an effective method for improving the fitness level of alcoholic patients.