Minimal Cooperation Research Articles

Minimal cooperation in bargaining

Mid-point domination requires that the solution outcome dominate or be dominated by a reference point. By investigating two different formulations of the condition, we present characterizations of the Nash and the Kalai-Rosenthal solutions for n-person bargaining problems.

Immitance Audiometry

Immitance audiometry is a safe, simple, reliable, and relatively objective method of determining middle-ear function that provides advantages for examining the difficult patient because minimal cooperation is needed. Acoustic-immitance measurements obtain sophisticated data that give us valuable information about the middle ear mechanism as a whole. It can be used in a quiet office environment. Immitance audiometry can confirm a doubtful otoscopic diagnosis and screen for ear disease. There are limitations to observer reliability with otoscopy, which has good sensitivity but poor specificity, in contrast to immitance audiometry. The tympanogram can be classified into four different patterns on the basis of its characteristics. These patterns are diagnostic, distinguishing normal function from various types of middle ear pathology. Immitance audiometry has very high sensitivity and specificity. The acoustic reflex, a contraction of the stapedius muscle following an intense auditory stimulus, can be valuable in determining a conductive hearing loss and many other otologic diagnoses. As a screening tool, immitance audiometry is most valuable in populations at risk for middle ear effusion, primarily those aged 7 months to 5 years. Significant improvements in measurements of ear function also allow us to be more precise in the diagnoses of otosclerosis, perforation of the tympanic membrane, ossicular discontinuity, facial nerve dysfunction, and brain stem disorders.

The Use of Electrical Current in the Treatment of Nonunions

The use of electrostimulation in the treatment of nonunions in human beings is gaining in popularity. Increased understanding of the electrophysiology of fracture healing has lead to advances in the utilization of electric currents to stimulate nonunions to heal without resorting to major orthopedic surgery and its attendant risks. Most workers report success rates of 75 to 85 per cent, which are comparable to rates achieved by more routine orthopedic techniques. Brighton suggested that the risk/benefit ratio was lower for direct-current treatment of nonunion than that associated with conventional bone-graft surgery in human beings. Such information is not yet available for the veterinary surgeon. However, some authors have questioned the glowing reports of successful electric stimulation of clinical nonunions, citing poor design of clinical trials, erratic or inappropriate selection of patients, and empiricism in interpretation of results. Although the use of electrotherapy for treatment of nonunions appears promising, much more work is needed to define those patients best able to respond favorably to such techniques. Nonunions in dogs and cats are now only rarely treated with electric current. To date, no major clinical studies have been published concerning such techniques, although much of the basic research in this area was done on animals. It would appear that the totally implantable stimulators have the most potential for use in small animals because minimal cooperation is required of the patient and client. Furthermore, such devices cannot be easily damaged or dislodged. Whether electric stimulation of nonunions in dogs and cats will replace or supplant conventional orthopedic techniques remains to be seen.

Studies on pulmonary ventilation using digital subtraction radiography. A preliminary report.

Digital subtraction radiography was used in 84 patients with suspected pulmonary embolism to obtain information about localized changes in ventilation of the lungs. Preliminary experiences in patients with carcinoma of the lung, emphysema and acute inflammatory diseases have also been obtained. Digital subtraction radiography is a simple, rapid and inexpensive method to obtain information about ventilation in the lungs. It is completely non-invasive and requires only minimal cooperation of the patient. The sensitivity appears to be as good as that of 133Xe radionuclide ventilation studies.

Reliability of a New Technique for the Determination of Vitamin B12 Absorption in Children

Summary:The fractional vitamin B12 absorption (FAB12) was determined in 39 patients with various gastrointestinal diseases by a double‐isotope technique, employing a single stool sample test (SSST), as well as a complete stool collection. The age of the patients ranged from 2.5 months to 16.2 years (mean 5.0 years). The test dose was administered orally and consisted of 0.5‐4.5 μg of 57CoB12 (approximately 0.05 μCi), carmine powder, and 2 mg 51CrCl3 (approximately 1.25 μCi) as the inabsorbable tracer. The whole‐body radiation to a 1‐year‐old child averaged only 20 mrad. The stool and napkin was collected and homogenized by addition of 300 ml “chromium sulfuric acid.” A 300‐ml sample of the homogenized stool and napkin, as well as 300 ml chromium sulfuric acid (75% v/v) containing the standards, were counted in a broad‐based well counter. The FAB12 determined by SSST employing the stool with the highest content of 51Cr (which corresponded to the most carmine‐colored stool) correlated closely to the FAB12 based on complete stool collection (r = 0.98, n = 39, p < 0.001). The reproducibility of FAB12 determined by SSST was assessed from double assays in 19 patients. For a mean value of 12%, the SD was 3%, which corresponded to a coefficient of variation (CV) of 25%. The excretion of 57Co and 51Cr in the urine was examined in six patients with moderate to severe mucosal damage and was found to be low. The gut transit time, as determined by the excretion time of ≥ 50% of the orally administered 51Cr, ranged from 4 to 100 h (mean 36 h, n = 39), and it was less than 12 h and 24 h in 7 and 13 patients, respectively. Conclusively, the SSST proved to be a very suitable technique for measurements of B12 absorption, even in children with mucosal damage of the intestine and short gut transit time. Further‐more, the method fulfilled the following requirements; (a) minimal cooperation and control of possible errors, (b) small radiation dose, (c) direct measurement of the B12 absorption, and (d) no need for flushing with B12.

Clinical electrophysiology in myasthenia gravis.

Effective diagnostic methods are of great importance in order to recognise myasthenic patients among those with muscle fatigability. Intracellular recordings are useful for research work within the field and for detailed description of the motor end-plate's physiology in the individual case. The method is not used for the routine diagnosis of myasthenia gravis. The decrement of the electrical muscle response with nerve stimulation is the most commonly used method. The diagnostic yield is higher in proximal muscles, in warmed muscles, after exercise, and after ischaemia. A significant number of patients may be undiagnosed with this technique. The mechanical response with nerve stimulation shows the same type of decrement but also an abnormal response to long stimulation. The diagnostic value of this is under dispute. Single fibre ENG needs more patient cooperation than do these tests. The diagnostic yield is significantly higher. Some patients considered to have myasthenia gravis do not show any abnormalities with this technique, particularly those with the pure ocular form. Conventional EMG is not useful for the diagnosis of myasthenia, but may be indicated in these patients when concurrent nerve or muscle disease is in question. Tests for eye movement fatique have not proved useful. Stapedius reflex fatigability is demonstrated in about the same proportion of patients as have positive SFEMG findings. The technique is not uncomfortable for the patient and requires minimal cooperation. The general usefulness must be assessed by further routine use. Even with the advent of immunological tests, neurophysiological investigations are indispensable in helping establish the diagnosis of myasthenia gravis. Discrepancies between the results comparing electrophysiological and immunological tests may indicate that myasthenia gravis is a heterogenous entity within which subgroups may be identified.

Radiographic localization of the acetabular component of a hip prosthesis.

The degree of anterior or posterior tilt of the acetabular cup can be established using fluoroscopy in patients with total hip prostheses. Since the technique is fast, painless, and requires minimal cooperation, it can be performed immediately following surgery. This method is suitable for postoperative evaluation of patients with total hip replacement and is also reproducible for serial analysis.

VENTILATION AND PERFUSION ASSESSMENT BY ELECTRICAL IMPEDANCE PLETHYSMOGRAPHY

Tetrapolar electrical impedance plethysmography has been employed in an attempt to describe regional and total ventilation and perfusion profiles at tidal volume range in patients with different pulmonary pathology. Atraumatic and requiring minimal cooperation, the determinations were performed on patients ranging in ages from 8 mo to 18 yrs. Resistive impedance changes of a 0.8 ma, 50 kHz constant current were detected from 1.5 cm2 electrodes linearly mounted in adhesive belts. These belts were applied horizontally above the diaphragm in 6 areas corresponding to upper, mid, and lower regions of the lungs. Interelectrode distances were varied to suit both patient size and the depth of tissue to be studied. Even current distribution found from isoresistance studies allowed the assumption of favorable resolution within the sample region. Deflections representing ventilatory and perfusion events were recorded simultaneously with their derived veiocities. From these blood flow pulses could be obtained using a forward extrapolation method. The data was then converted into ventilation and perfusion indices. The regional distribution of the ratios of ventilation and perfusion values was different from that of other methods because these values were not corrected for unit volume. In 6 cases of atelectases, hypoperfusion, consolidation, and lung abscess confirmed by conventional methods, low ventilation and perfusion impedance indices corresponded with diseased areas, whereas they were higher in more normal lung fields.

Feeding Tube Placement in the Debilitated Patient

To the Editor.— Nutritional care of the postoperative or critically ill patient has received increased attention in current medical literature. Although the technology of total parenteral hyperalimentation has burgeoned, continuous enteral alimentation through a pediatric feeding tube is often the preferred therapeutic route. Passage of a No. 8 French nasogastric feeding tube in a cooperative patient with an intact swallowing reflex is not a difficult procedure. However, frequently a patient is either unwilling or unable to swallow, and the thin, flexible tube is found curled in the hypopharynx. When routine placement of a pediatric feeding tube fails, we use an alternative method that is simple, rapid, and requires minimal patient cooperation. The technique involves the use of a flexible-channel biopsy forceps from a fiberoptic endoscope. The feeding tube is first advanced through the patient's nose and brought out through the mouth. The distal end of the tube is then grasped

THE MEASUREMENT OF SHARING AND COOPERATION AS EQUITY EFFECTS AND SOME RELATIONSHIPS BETWEEN THEM1

The initial objective was to determine whether an increase in cooperative responses (minimal cooperation) was also accompanied by an increase in the degree of correspondence in the number of reinforcers of the two subjects (maximal cooperation). Correct matching-to-sample responses of seven pairs of male adolescents were reinforced with money. On each trial, a subject could (1) give the matching-to-sample problem to his coactor (give or cooperative responses), or (2) take the problem for himself (take responses). The first member of the pair to respond made the choice. Correspondence did increase under this procedure as compared to a baseline where problems were distributed randomly. However, the increased correspondence usually resulted from take responses rather than cooperative give responses. This equitable method of problem distribution, designated as sharing, was characterized by the subjects alternately taking problems. The spacing of daily sessions may have been partly responsible for the high degree of correspondence, because correspondence did not increase within the usual number of sessions when the sessions were massed, i.e., all in one day. Daily sessions require cooperative responses, i.e., each subject has to show up each day for the other to earn money, and this dependency upon the coactor's behavior may facilitate some sharing or cooperation to ensure the coactor's attendance.