A 20-minute back massage enhanced mood and reduced stress in the spouses of cancer patients, according to recent research.

“The Effects of Therapeutic Back Massage on Psychophysiologic Variables and Immune Function in Spouses of Patients With Cancer” was conducted by staff at the Duquesne University School of Nursing in Pittsburgh, Pennsylvania.

Forty-two spouses, male and female, of patients with cancer participated in the study. They were randomly assigned to either the massage group or the control group.

Spouses in the massage group received one 20-minute back massage, consisting of long, slow strokes that produced a “sedative-like effect” on the subject.

Spouses in the control group read from an emotionally neutral book for 20 minutes. They each received a back massage after the study ended.

Outcome variables were mood, perceived stress, heart rate, systolic and diastolic blood pressure, and natural-killer-cell activity. Natural killer cells are effective against virus-infected cells.

The outcomes were measured at three different time points: before the back massage or reading session, immediately after the back massage or reading session, and 20 minutes after the back massage or reading session.

Mood was evaluated on the Profile of Mood States. Stress was measured on the Visual Analogue Scale. Natural-killer-cell activity was analyzed by blood draws.
Immediately following the massage, and 20 minutes thereafter, spouses in the massage group showed a significant decrease in total mood disturbance on the Profile of Mood States and a significant decrease in perceived stress on the Visual Analogue Scale.

No significant changes were found for heart rate, systolic and diastolic blood pressure, or natural-killer-cell activity.

“It may be necessary to administer massage over several weeks to see an increase in [natural-killer-cell activity] because relaxation-induced immune function change is more than likely dependent on regular practice,” states the study’s author.

However, a correlation was made between mood and natural-killer-cell activity. Spouses with a high score for negative mood on the Profile of Mood States had lower levels of natural-killer-cell activity. Spouses with a lower score for negative mood had higher levels of natural-killer-cell activity. This revealed a significant inverse relationship between mood and natural-killer-cell activity.

“This research suggests that [therapeutic back massage] may benefit spouses of patients with cancer by enhancing positive mood and reducing perceived stress,” states the study’s author. “Thus, [therapeutic back massage] may help spouses face the challenge of living with and caring for an ill partner with cancer.”

- Source: Duquesne University School of Nursing in Pittsburgh, Pennsylvania. Author: Linda M. Goodfellow, Ph.D., R.N. Originally published in Nursing Research, September/October 2003, Vol. 52, No. 5, pp. 318-328.

A recent analysis of 37 massage-therapy studies showed that massage has a significant overall effect on people, specifically in the reduction of state anxiety, blood pressure, heart rate, trait anxiety, depression and pain.

“A Meta-Analysis of Massage Therapy Research” was conducted by staff at the University of Illinois at Urbana-Champaign Department of Educational Psychology.

Studies that were included in the analysis had to meet a number of criteria, such as the use of a bodywork modality consistent with the definition of massage as “the manual manipulation of soft tissue to promote health and well-being.”

Each study also had to compare a massage-therapy group with one or more non-massage control groups; use random group assignment; and report enough data for “a between-groups effect size to be generated on at least one dependent variable of interest,” state the study’s authors.

The 37 studies selected for the analysis used a total of 1,802 participants. Of these, 795 received massage therapy and 1,007 received a comparison treatment.

Researchers looked at nine dependent outcome variables among the studies, to see if the results would show consistent improvement with massage therapy. The single-dose (short-term) outcomes analyzed were state anxiety, negative mood, pain assessed immediately after massage, heart rate, blood pressure and cortisol levels. The multiple-dose (long-term) effects analyzed were trait anxiety, depression and delayed assessment of pain.

State anxiety is temporary and situation-specific, while trait anxiety is the innate tendency to be anxious.

The mean results of the 37 studies showed significant reductions in state anxiety, blood pressure, heart rate, trait anxiety, depression and delayed assessment of pain.

“This meta-analysis supports the general conclusion that [massage therapy] is effective. Thirty-seven studies yielded a statistically significant overall effect as well as six specific effects out of nine that were examined,” state the study’s authors.

Mean results for negative mood, immediate assessment of pain and cortisol were not significant.

Massage therapy’s most powerful effects, according to the combined results of the studies, were the reduction of trait anxiety and depression.

“The average [massage therapy] participant experienced a reduction in trait anxiety that was greater than 77 percent of comparison group participants, and a reduction of depression that was greater than 73 percent of comparison group participants,” state the study’s authors. “Considered together, these results indicate that [massage therapy] may have an effect similar to that of psychotherapy.”

The authors suggest further research into whether massage therapy is as effective as psychotherapy, and whether a combination of the two is more effective than either one alone.

- Source: University of Illinois at Urbana-Champaign Department of Educational Psychology. Authors: Christopher A. Moyer, James Rounds and James W. Hannum. Originally published in Psychological Bulletin 2004, Vol. 130, No. 1, pp. 3-18.

Acupressure significantly improved dyspnoea - shortness of breath - in patients with chronic obstructive pulmonary disease, according to a recent study.

“Effectiveness of acupressure in improving dyspnoea in chronic obstructive pulmonary disease” was conducted by staff at the Jen Teh Junior College of Medicine, Nursing and Management, in Miaoli, Taiwan; the Institute of Health and Welfare Policy and the Institute of Clinical Nursing at National Yang-Ming University, in Taipei, Taiwan; and the Institute of Chinese Medical Science at Chinese Medical College, in Taichung, Taiwan.

The study involved 44 subjects with chronic obstructive pulmonary disease. Subjects’ average age was 73, and most of them were men.

The participants were randomly assigned to either a true-acupressure group or a sham-acupressure group. Both groups had five sessions of acupressure per week, 16 minutes per session, for four weeks, for a total of 20 sessions.

In the true-acupressure group, the acupressure protocol involved the following acupoints: Great Hammer (GV14), Celestial Chimney (CV22), Lung Transport (B13), Kidney Transport (B23) and Fish Border (L10).

In the sham-acupressure group, the acupressure protocol involved the following acupoints, which are used to promote intestinal movement: Shang Hill (Sp5), Supreme White (Sp3) and Large Pile (Liv1).

Activity, fatigue and dyspnoea were rated at the beginning and end of the study using the Pulmonary Function Status and Dyspnoea Questionnaire-Modified (PFSDQ-M). Subjects also rated their levels of anxiety associated with dyspnoea using the State Anxiety Inventory at the start and finish of the study, and took a six-minute walking distance test as well, to evaluate tolerance of activity.
Oxygen saturation in the finger of each participant was measured before and after each acupressure session using a pulse oximeter.

Mean scores on the PFSDQ-M showed that dyspnoea in the true-acupressure group decreased significantly after the intervention and that fatigue levels for this group improved significantly, as compared to the sham-acupressure group.

Results of the State Anxiety Inventory showed that, on average, anxiety was significantly lower in the true-acupressure group than the sham group at the conclusion of the study.

Subjects in the true-acupressure group also improved significantly on the six-minute walking test, indicating that they had more tolerance for activity than the sham group.

Mean oxygen-saturation scores for the true-acupressure group were significantly greater than the sham group following each acupressure session, which suggests improved pulmonary function.

“We found significantly greater improvements in patients receiving acupressure at true acupoints compared with those receiving acupressure at sham points,” state the study’s authors. “This improvement related to all the variables studied and suggests that people with [chronic obstructive pulmonary disease] would benefit from acupressure at true acupoints.”

- Source: Jen Teh Junior College of Medicine, Nursing and Management, in Miaoli, Taiwan; Institute of Health and Welfare Policy, Institute of Clinical Nursing at National Yang-Ming University, in Taipei, Taiwan; Institute of Chinese Medical Science at Chinese Medical College, in Taichung, Taiwan. Authors: Hua Shan Wu, R.N.; Shiao-Chi Wu, Ph.D.; Juang-Geng Lin, Ph.D.; and Li-Chan Lin, Ph.D., R.N. Originally published in the Journal of Advanced Nursing, 2004, Vol. 45, No. 3, pp. 252-259.

Moderate-pressure massage therapy significantly decreased stress and heart rate, and caused a shift toward left frontal electroencephalogram (EEG) asymmetry, suggesting that the massage was perceived as pleasant and relaxing, according to a recent study involving 36 healthy adults.

“Massage therapy of moderate and light pressure and vibrator effects on EEG and heart rate” was conducted by staff at the University of Miami School of Medicine Touch Research Institute, in Miami, Florida, to compare the effects of these three types of touch.

Participants were randomly assigned to receive moderate-pressure massage, light-pressure massage or vibratory massage, using the Thumper massage tool on the deep-pressure setting at 40Hz. Subjects in all groups received 10 minutes of stimulation to the back, shoulders and arms, while remaining fully clothed in a massage chair.

Before the stimulation began, an EEG cap was placed on the subjects’ heads, EKG electrodes were placed along the arms, and subjects completed the following assessments: demographic questionnaire, State Anxiety Inventory, Visual Analogue Stress/Relaxation Scale, and the Touch Aversion Questionnaire.

There was then a three-minute baseline period before the start of the 10-minute stimulation, followed by three minutes post-session. Subjects then completed the State Anxiety Inventory and the Visual Analogue Stress/Relaxation Scale once again.

Results of the study showed that anxiety decreased for all three groups, but subjects in the moderate-pressure group showed the greatest decrease in self-reported stress.
Those who received moderate-pressure massage also showed the greatest shift toward left frontal EEG asymmetry, which indicates a positive response to the stimulation. This group experienced a significant decrease in heart rate during and after the massage, while the light-massage group showed a significant increase in heart rate following the session. The vibratory massage group showed a marginal increase in heart rate after the massage.

“Taken together these findings indicate that moderate pressure massage resulted in enhanced relaxation, while the light pressure massage resulted in physiological arousal and decreased relaxation,” state the study’s authors. “Further, the vibratory stimulation appeared to have negligible effects on physiological levels of arousal and/or relaxation.”

- Source: University of Miami School of Medicine Touch Research Institute, in Miami, Florida. Authors: Miguel A. Diego, Tiffany Field, Ph.D., Chris Sanders, Maria Hernandez-Reif, Ph.D. Originally published in International Journal of Neuroscience, 2004, Vol. 114, pp. 31-45.

Soaking in hot mineral pools once a week significantly improved the symptoms of osteoarthritis and reduced the amount of medication taken by people with the condition, according to a recent study.

“The effect of balneotherapy on osteoarthritis. Is an intermittent regimen effective?” was conducted by staff of the Asaf-Harofe Medican Center, in Zerifin, Israel, and the Tel Aviv University Sackler Faculty of Medicine, in Tel Aviv, Israel.

Seventy-two people with knee osteoarthritis for more than three months participated in the study. They were randomly assigned to either the no-treatment control group or the balneotherapy group.

Subjects in the balneotherapy group soaked in the natural thermal springs at Chamei Yoav, a spa in central Israel, once a week for six weeks. They bathed in the pools for 15 minutes, followed by one hour of rest, and 15 more minutes of soaking. The water at Chamei Yoav is about 98 degrees Fahrenheit and contains sodium, chloride, bicarbonate, calcium, bromide, magnesium, potassium and sulphate.

All participants were evaluated by the same doctor seven days before the start of the spa therapy, four weeks into the therapy, at the end of the six-week spa-therapy period, and four weeks after the spa therapy had stopped.

Pain was assessed on a visual analogue scale, and subjects and their physician rated changes in the severity of the disease. The number of non-steroidal anti-inflammatory drugs (NSAID) and/or analgesics taken was recorded at each evaluation as well.
Results of the study showed that, after six weeks of spa therapy, there was a significant improvement in symptoms of osteoarthritis in the balneotherapy group, and the improvement was sustained until the end of the study, four weeks after the spa therapy had ended.

After four weeks of spa therapy, there was also a significant improvement in participant and physician evaluation of disease severity. The improvement peaked after the full six weeks of spa therapy, and the peak was maintained until the end of the study four weeks later.

The number of NSAID and/or analgesic tablets taken by subjects in the balneotherapy group was also significantly reduced. There were no such changes in the no-treatment control group.

“We showed that balneotherapy … on a once weekly basis, might significantly improve symptoms of [osteoarthritis],” state the study’s authors. “Another important observation was the ability of our patients to reduce their NSAID and analgesic consumption during this period.”

- Source: Asaf-Harofe Medical Center, in Zerifin, Israel, and Tel Aviv University Sackler Faculty of Medicine, in Tel Aviv, Israel. Authors: Moshe Tishler, Oskar Rosenburg, Ofer Levy, Iris Elias and Mirit Amit Vazina. Originally published in the European Journal of Internal Medicine, 2004, Vol. 15, pp. 93-96.

A study of the long-term effects of massage and aromatherapy on the physical and psychological symptoms of patients with advanced cancer showed that the intervention significantly improved subjects’ quality of sleep, but provided only short-term benefits for pain and anxiety.

“A randomized controlled trial of aromatherapy massage in a hospice setting” was conducted by staff at Princess Alice Hospice, in Esher, Surrey, United Kingdom; the North Surrey Primary Care Trust, in Surrey, United Kingdom; and The Royal Marsden Hospital, in Sutton, Surrey, United Kingdom.

Forty-two subjects diagnosed with cancer were randomly assigned to receive either massage with lavender essential oil and an inert carrier oil; massage with an inert carrier oil only; or no massage.

Subjects in the massage groups received a 30-minute standardized back massage once a week for four weeks. Subjects in the no-massage group - the control group - completed the researchers’ questionnaires and assessments, but received no intervention.

Evaluations took place at the beginning and end of the study, using a Visual Analogue Scale and a Modified Tursky Pain Descriptors Scale for pain intensity; the Verran and Snyder-Halpern sleep scale; the Hospital Anxiety and Depression scale; and the Rotterdam Symptom Checklist.

Evaluations of pain, sleep and the Hospital and Anxiety Depression scale also took place on a weekly basis.

Results of the study showed that subjects in both massage groups had significantly better sleep scores than subjects in the control group at the end of the study.
“Our results suggest that aromatherapy and massage may have a beneficial effect on sleep quality in patients with advanced cancer,” state the study’s authors.

The study also showed a statistically significant reduction in pain for both the massage groups following the second massage treatment, but no long-term pain reduction at the end of the study.

There were no statistically significant long-term differences among groups for either the Hospital Anxiety and Depression scale or the Rotterdam Symptom Checklist. Subjects in the massage-only group, however, had significantly better scores on the Hospital Anxiety and Depression scale after the second and fourth massage sessions.

“In this study, we did not set physical or psychological entrance criteria and patients were, therefore, recruited with varying levels of pain, sleep difficulties, anxiety and other symptoms,” state the study’s authors. “These findings suggest that if the inclusion criteria were refined, the measurable benefits of treatment may be greater.”

- Source: Princess Alice Hospice, in Esher, Surrey, United Kingdom; North Surrey Primary Care Trust, in Surrey, United Kingdom; The Royal Marsden Hospital, in Sutton, Surrey, United Kingdom. Authors: Katie Soden, Karen Vincent, Stephen Craske, Caroline Lucas and Sue Ashley. Originally published in Palliative Medicine, 2004, No. 18, pp. 87-92.

Daily physical activity and massage help increase bone mineralization in premature infants, according to recent research.

“Physical Activity Combined with Physical Activity Massage Improves Bone Mineralization in Premature Infants: A Randomized Trial” was conducted by staff at George Washington University Hospital and Children’s National Medical Center, in Washington, D.C.; and the Ain Shams University School of Medicine, in Cairo, Egypt.

Thirty premature infants with a gestational age of 35 weeks or less and a postnatal age of less than two weeks participated in the study. The infants were randomly assigned to either the control group or the activity group, where they received physical activity and massage.

Daily range-of-motion exercises with gentle compression and extension/flexion to the upper and lower extremities composed the exercise in the activity group. Five repetitions of each movement were performed on the infants’ wrists, elbows, shoulders, ankles, knees and hips.

The massage portion of the activity group consisted of slow, gentle strokes to each part of the infants’ body. While prone, the infant was stroked for one minute from the head and face to the neck; one minute from the neck across the shoulders; one minute from the upper back to the waist; one minute from the thigh to the foot on both legs; and one minute from the shoulder to the hand and back to the shoulder on both arms.
Exercise and massage were provided to each infant until they reached a weight of approximately four pounds. The control group did not receive any intervention. Type of feeding was recorded for both groups, including the amount of calories, calcium, phosphorus and protein given per day.

Outcome measures were C-terminal procollagen peptide (PICP), urine pryidinoline (urine Pyd), serum calcium, alkaline phosphatase and parathyroid hormone (PTH), which are biomarkers of bone formation and resorption. These were measured at the start of the study and when they reached approximately four pounds of body weight.

Results of the study showed that mean PICP concentration was significantly higher for the activity group at the end of the study, as compared to the control group. Mean PICP had increased in the activity group and decreased in the control group.

Mean PTH levels were also significantly higher for the activity group at the end of the study, as compared to the control group. Increases in these substances indicate an increase in bone mineralization.

Serum calcium and urine Pyd increased for both groups over the course of the study, and serum alkaline phosphatase did not change significantly for either group.

“Physical activity combined with infant massage stimulates bone formation in premature infants as evidenced by an increase in PICP, a biochemical marker of bone formation, and an increase in PTH activity, which may further stimulate bone growth and mineralization,” state the study’s authors.

- Source: George Washington University Hospital and Children’s National Medical Center in Washington, D.C.; Ain Shams University School of Medicine in Cairo, Egypt. Authors: Hany Aly, M.D., Mohamed F. Moustafa, Sahar M. Hassanein, An N. Massaro, Hanna A. Amer and Kantilal Patel. Originally published in Journal of Perinatology, 2004, Vol. 24, pp. 305-309.

Acupressure and massage ease fatigue and depression in people with end-stage renal disease - kidney failure - who are undergoing hemodialysis, a recent study reported.

“The effect of Acupressure with Massage on Fatigue and Depression in Patients with End-Stage Renal Disease” was conducted by staff at the National Tainan Institute of Nursing Department of Nursing, in Tainan, Taiwan, and the National Taipei College of Nursing Graduate Institute, in Taipei, Taiwan.

Sixty-two people with end-stage renal disease undergoing hemodialysis participated in the study. They were randomly assigned to either the experimental group, where they received acupressure and massage, or the control group, where they continued to receive standard care.

Subjects in the experimental group received acupressure for 12 minutes per day, followed by a three-minute massage of the legs, three days a week, for four weeks. The acupressure points Zusanli, Sanyinjiao, Taixi and Yungchuan were deemed appropriate for easing fatigue and depression.

These points were pressed and rubbed using the pads of the fingers with a force of about three-to-five kilograms for five seconds, with a one-second release at the end. Each point was stimulated for three minutes. After 12 minutes of acupressure, subjects’ legs were massaged for three minutes.

Researchers used the revised Piper Fatigue Scale to measure fatigue, and the Chinese version of Beck’s Depression Inventory was used to measure depression, at the beginning and end of the four-week study.
The results of the study revealed a significant decrease in perceived fatigue from the start to the finish of the study for subjects in the experimental group, whereas the control group showed no significant difference in perceived fatigue from pretest to post-test.

There was also a significant improvement from pretest to post-test on depression scores for the experimental group. The control group showed no significant difference in depression scores from the beginning to the end of the study.

The study’s authors concluded that acupressure with massage could effectively improve fatigue and depression in people with end-stage renal disease, and that it should be considered when caring for this population.

“Assessment of [end-stage renal disease] patients’ fatigue and depression should be an essential part of nursing practice, and clinicians may consider providing acupressure therapy as a method for improving dialysis patients’ fatigue and depression,” state the study’s authors. “Nurses, patients and their families could be easily trained to administer acupressure to those who have fatigue and depression.”

- Source: National Tainan Institute of Nursing Department of Nursing, in Tainan, Taiwan, and National Taipei College of Nursing Graduate Institute, in Taipei, Taiwan. Authors: Yi-Ching Cho, R.N., Shiow-Luan Tsay, R.N., Ph.D. Originally published in Journal of Nursing Research, 2004, Vol. 12, No. 1, pp.51-58.

Healing Touch can decrease pain, improve vitality and increase physical functioning in women undergoing radiation for gynecological or breast cancer, according to recent research.

Healing Touch and Quality of Life in Women Receiving Radiation Treatment for Cancer: A Randomized Controlled Trial” was conducted by staff at Barnes-Jewish Hospital in St. Louis, Missouri, and the School of Social Service, St. Louis University, in St. Louis, Missouri.

The study involved 62 women receiving radiation treatment for newly diagnosed gynecological or breast cancer. The women were randomly assigned to receive either Healing Touch or mock treatment, along with standard care, and were blind to their actual group assignment.

Subjects in both groups received a total of six 30-minute sessions; each one took place immediately after radiation treatment. The first session happened no more than one-third of the way through the radiation schedule. The next four sessions happened on a weekly basis, and the last session was given four weeks later.
During the sessions, subjects laid fully clothed on a massage table. A three-by-three-foot opaque screen was placed between the subject’s head and her body so she could not see who was providing the session or what they were doing.

Each Healing Touch session consisted of four phases: healer preparation, such as centering; pretreatment energetic assessment; Healing Touch intervention; and post-treatment energetic assessment.

The mock treatments were provided by laypeople with no training in or knowledge of Healing Touch. These people were instructed to walk around the table and stand at the end of it, keep their hands by their sides, and not focus any thoughts on the subject, but to think of simple math problems.

The study’s primary outcome measure was health-related quality of life, which was assessed before and after the study using the SF-36, a 36-item questionnaire from the Medical Outcomes Study at the Rand Corporation. The SF-36 measures nine health-related areas, such as bodily pain, general mental health, vitality, and limitations in social activities due to physical or emotional problems. Scores range from zero to 100, and higher scores are associated with better functioning.

The overall average score for all subjects at baseline was 53. After intervention, the Healing Touch group had an overall average score of 63.3, whereas the mock-treatment group had an overall average score of 54.3.

The Healing Touch group scored higher than the mock-treatment group in all nine areas of the health-related quality-of-life assessment. Subjects in the Healing Touch group showed statistically significant improvements in pain, vitality and physical functioning.

Subjects who received Healing Touch demonstrated better [health-related quality of life] following radiation treatment than their counterparts who received mock treatment,” state the study’s authors. “The significant effects of [Healing Touch] on vitality, pain and physical functioning in this study lend support to the potential value of [Healing Touch] in improving the health-related quality of life of women with gynecological or breast cancer who undergo radiation therapy.

Source: Barnes-Jewish Hospital, St. Louis, Missouri, and the School of Social Service, St. Louis University, St. Louis, Missouri. Authors: Cynthia A. Loveland Cook, Ph.D., R.N.; Joanne F. Guerrerio, R.N.; and Victoria E. Slater, Ph.D., R.N. Originally published in Alternative Therapies in Health and Medicine, 2004, Vol. 10, No. 3, pp. 34-40.

A 20-minute foot-and-hand massage significantly reduced subjects’ perception of pain intensity and distress the day after surgery, and also lowered their heart and respiratory rates, according to a recent study.

Foot and Hand Massage as an Intervention for Postoperative Pain” was conducted by staff at Clarion Health Partners Methodist Hospital and Indiana University School of Nursing, in Indianapolis, Indiana.

Eighteen subjects who underwent surgery participated in this study the day after their operations. Participants were age 20 or older, and recovering from gastrointestinal, gynecological, urological, head, neck or plastic surgery. They each received pain medication one-to-four hours before the massage intervention and had asked for an intervention to relieve their pain the day after surgery. All subjects reported that the surgical wound was the area that hurt most.

Pain intensity and distress scores, heart rate, respiratory rate and blood pressure were measured before and immediately after the 20-minute massage. Subjects were also asked to rate the percentage of pain relief from the pain medication before the massage and the percentage of pain relief from the massage following the intervention.

The same person provided the foot-and-hand massage to all participants. The massage consisted of petrissage, friction and kneading for five minutes on each hand and each foot, for a total of 20 minutes.

Perceived pain intensity was measured using a scale that ranged from 0 (no pain) to 10 (pain as bad as you can imagine). Perceived distress was measured on a similar scale, ranging from 0 to 10. Perceived pain relief, from both the pain medication and the massage intervention, was measured on a percentage scale, ranging from 0 percent (no relief) to 100 percent (complete relief).

Results of the study showed significant reductions in both pain intensity and distress after the 20-minute massage, as well as significant decreases in heart rate and respiratory rate, but not systolic and diastolic blood pressure.

The findings from the study indicated that a 20-minute foot and hand massage significantly reduced both pain intensity and distress resulting from incisional pain on the first postoperative day,” state the study’s authors. “Foot and hand massage appears to be an effective, inexpensive, low-risk, flexible, easily applied strategy for postoperative pain management.”

- Source: Clarion Health Partners Methodist Hospital and Indiana University School of Nursing, Indianapolis, Indiana. Authors: Hsiao-Lan Wang, R.N., and Juanita F. Keck, R.N. Originally published in Pain Management Nursing, June 2004, Vol. 5, No. 2, pp. 59-65.