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Jupiter’s upper atmosphere is considerably hotter than expected from the amount of sunlight that it receives1–3. Processes that couple the magnetosphere to the atmosphere give rise to intense auroral emissions and enormous deposition of energy in the magnetic polar regions, so it has been presumed that redistribution of this energy could heat the rest of the planet4–6. Instead, most thermospheric global circulation models demonstrate that auroral energy is trapped at high latitudes by the strong winds on this rapidly rotating planet3,5,7–10. Consequently, other possible heat sources have continued to be studied, such as heating by gravity waves and acoustic waves emanating from the lower atmosphere2,11–13. Each mechanism would imprint a unique signature on the global Jovian temperature gradients, thus revealing the dominant heat source, but a lack of planet-wide, high-resolution data has meant that these gradients have not been determined. Here we report infrared spectroscopy of Jupiter with a spatial resolution of 2 degrees in longitude and latitude, extending from pole to equator. We find that temperatures decrease steadily from the auroral polar regions to the equator. Furthermore, during a period of enhanced activity possibly driven by a solar wind compression, a high-temperature planetary-scale structure was observed that may be propagating from the aurora. These observations indicate that Jupiter’s upper atmosphere is predominantly heated by the redistribution of auroral energy.

Face-to-face outreach activities with scientific researchers provide schools with tangible role models, real world context for the curriculum, and a unique shared experience for groups of students. Moving from face-to-face to online engagement at short notice represents a unique challenge for the continuation of many outreach activities. The development, logistics, and feedback for a new series of live virtual sessions between university-based researchers and secondary schools are described here. Stories from the Lab was developed and run with science teachers during the initial phase of the COVID-19 lockdown in Ireland. In addition to the benefits afforded to teachers and students, it also provided the researchers with suitable work experience and peer-learning as part of their structured Ph.D. program.

This work describes the design, building, and testing of miniature, low-cost LED–LDR colorimeters for absorption-spectrophotometry experiments. It also describes using these colorimeters for simplified context-based-learning (CBL) activities in school teaching laboratories and for public-engagement events. The colorimeters are simple and robust, performing well against a conventional benchtop UV–vis spectrophotometer. Data collection and analysis is quick and intuitive, allowing for efficient turnaround between groups and making it particularly useful at public-engagement events. The experiments and activities described here are based on real-life examples to emphasize the usefulness of chemical analysis and quantification in everyday life.

We present ground‐based observations of Jupiter's H3+aurorae over four nights in April 2016 while the Juno spacecraft was monitoring the upstream interplanetary magnetic field. High‐precision maps of auroral H3+densities, temperatures, and radiances reveal significant variabilities in those parameters, with regions of enhanced density and emission accompanied by reduced temperature. Juno magnetometer data, combined with solar wind propagation models, suggest that a shock may have impacted Jupiter in the days preceding the observation interval but that the solar wind was quiescent thereafter. Auroral H3+temperatures reveal a downward temporal trend, consistent with a slowly cooling upper atmosphere, such as might follow a period of shock recovery. The brightest H3+emissions are from the end of the period, 23 April. A lack of definitive signatures in the upstream interplanetary magnetic field lends supporting evidence to the possibility that this brightening event may have been driven by internal magnetospheric processes. For the first time, Jupiter's auroral temperatures are mapped, while the upstream solar wind magnetic field is measured in situMaps of northern and southern H3+aurorae show significant variability in four observations spaced across 11 daysAuroral H3+intensifications are found to be dominated by density enhancements rather than temperature increases

The Cassini spacecraft revealed that Saturn's magnetic field displayed oscillations at a period originally thought to match the planetary rotation rate but later found not to. One of many proposed theories predicts that a polar twin‐cell neutral weather system drives this variation, producing observable differences in flows within Saturn's ionosphere. Here, using spectral observations of auroral H3+${\mathrm{H}}_{3}^{+}$emission lines taken by the Keck Observatory's Near Infrared Echelle Spectrograph (Keck‐NIRSPEC) in 2017, we derive ion line‐of‐sight velocity maps after grouping spectra into rotational quadrants matching phases of the planetary magnetic field. We measure 0.5 km s−1wind systems in the ionosphere consistent with predicted neutral twin‐vortex flow patterns. These findings demonstrate that neutral winds in Saturn's polar regions cause the rotational period, as determined via the magnetic field, to exhibit differences and time variabilities relative to the planet's true period of rotation in a process never before seen within planetary atmospheres. We observed Saturn's northern aurorae in the infrared using the Keck Observatory in Mauna Kea, Hawaii over the course of June, July and August of 2017. Using this data we investigate the motion of an ion, H3+${\mathrm{H}}_{3}^{+}$, in the planet's upper atmosphere. This is done after first placing the data into four groups corresponding to the rotational phase of the planet's magnetic field. By doing so we are able to detect twin‐vortex flows in the upper atmosphere of Saturn, consistent with theories that predict the presence of such a polar feature, thus providing direct evidence that Saturn's measured variable rotation rate is driven by these flows. These twin‐vortex flows are ultimately responsible for the time differences relative to the planet's true rotation period observed throughout Saturn's planetary environment. Keck‐NIRSPEC observations of Saturn's northern H3+infrared auroral emission from 2017 are analyzedFirst clear picture of how the ionosphere moves in relation to planetary period currents is providedSaturn's measured variable rotation rate is driven by twin‐vortex flows in the upper atmosphere Keck‐NIRSPEC observations of Saturn's northern H3+infrared auroral emission from 2017 are analyzed First clear picture of how the ionosphere moves in relation to planetary period currents is provided Saturn's measured variable rotation rate is driven by twin‐vortex flows in the upper atmosphere

This work describes the design and testing of a low-cost light-emitting diode (LED)-based nephelometer for turbidity analysis. It also describes the use of this nephelometer for context-based learning (CBL) experiments designed for teaching laboratories. The LED nephelometer is simple, low-cost, and robust, providing similar results as a commercial device. Data collection and analysis is quick and intuitive, allowing time and opportunity for discussion about the analytical process and the chemistry involved. The experiments described here are based on real-world applications to emphasize the usefulness of chemical analysis and quantification of turbidity in everyday life.

The temperatures of giant-planet upper atmospheres at mid- to low latitudes are measured to be hundreds of degrees warmer than simulations based on solar heating alone can explain. Modelling studies that focus on additional sources of heating have been unable to resolve this major discrepancy. Equatorward transport of energy from the hot auroral regions was expected to heat the low latitudes, but models have demonstrated that auroral energy is trapped at high latitudes, a consequence of the strong Coriolis forces on rapidly rotating planets. Wave heating, driven from below, represents another potential source of upper-atmospheric heating, though initial calculations have proven inconclusive for Jupiter, largely owing to a lack of observational constraints on wave parameters. Here we report that the upper atmosphere above Jupiter’s Great Red Spot—the largest storm in the Solar System—is hundreds of degrees hotter than anywhere else on the planet. This hotspot, by process of elimination, must be heated from below, and this detection is therefore strong evidence for coupling between Jupiter’s lower and upper atmospheres, probably the result of upwardly propagating acoustic or gravity waves.

Objectives: To assess outcomes in patients with spinal cord injury (SCI) and a tracheostomy tube (TT), before and after the introduction of a tracheostomy review and management service (TRAMS) for ward-based patients.

tert -Butyl hydroquinone (TBHQ) has important and functional uses in consumer and commercial applications, some of which involve human exposure primarily through dermal contact. To assist in the safety evaluation of TBHQ, this study was conducted to determine whether TBHQ would produce changes in skin pigmentation after repeated dermal application to black guinea pigs. Hydroquinone (HQ) and hydroquinone monomethyl ether (HQMME) were used as positive controls. TBHQ and HQ were tested at concentrations of 0.1, 1.0 and 5.0%, while HQMME was tested at a concentration of 10.0%. Groups of five males and five females were dosed with TBHQ, HQ, or the vehicle (hydrophilic ointment) daily (M--F) for 13 weeks. In addition, animals (five males, five females) treated with HQMME received 13 doses over a 3-week period. The application site was evaluated weekly for degree of pigmentation loss and irritation. Twenty-four hours after final application, sites were evaluated for depigmentation, irritation and hyperpigmentation. Subsequently, the application site was depilated and re-evaluated for the same endpoints. Repetitive exposure to concentrations of 1.0% and 5.0% TBHQ and HQ were slightly to moderately irritating, while 0.1% of each of these test materials produced only weak irritant responses. No irritant responses to hydrophilic ointment were observed and HQMME produced weak irritant responses after 2 weeks. Neither 0.1% TBHQ nor HQ produced depigmentation, while 20% of animals dosed with 1.0% TBHQ and 30% of animals dosed with 1.0% HQ had spotty or uniform loss of pigment at the site of treatment. Approximately 40% of animals dosed with 5% TBHQ or HQ were depigmented at the treatment site at the final evaluation. HQMME produced complete depigmentation of the skin and hair in all animals. Hyperpigmentation of the treatment site was observed in 80-100% of animals in all groups (with the exception of HQMME-treated animals, treated for only 3 weeks), which may be attributable to the use of hydrophilic ointment as the vehicle, the application procedure, or simply clipping hair from the skin. Thus, this study showed that TBHQ causes depigmentation in black guinea pigs at concentrations of 1% or greater, but that a no-effect threshold for this endpoint exists at a concentration between 0.1 and 1.0%.

Thirty-five participants from eight countries attended the third workshop sponsored by the L. H. Gray Trust (with additional funding from the Cancer Research Campaign). The forum was a unique opportunity to bring together clinicians and scientists with a variety of backgrounds to discuss the biological targeting of therapeutic radiation.

The zero-address code output from a computer compiler proves to be useful in producing computer enhanced learning material in mathematics education. The authors adapted a program to produce this code for mathematical expressions. This code is then interpreted in a number of different ways which prove useful to the teacher. In particular, programs are produced capable of evaluating and plotting non-continuous mathematical functions, and, symbolically differentiating a function in the variable x.

In this paper we discuss a study conducted in Ireland to investigate pupils attitudes to school mathematics. The authors feel this is a neglected area of research which could produce useful insights for practitioners in mathematics education.The study is described in some detail and the outcomes are discussed. We feel that the issues encountered are universal in mathematics education.

The authors are encouraged by the outcome of classroom tests of a new approach to teaching programming to beginners in schools. This approach is based on structured programming and emphasizes general problem-solving strategies while considerations related to coding and syntax are deferred until solutions are found. The new method employs a pedagogical representation of the interplay between problem analysis, algorithm design and implementation language. This representation was specially devised to facilitate the teaching and learning of programming skills. The authors have found the method to be effective with students in the classroom and with teachers on in-service courses.

Experiences with a Keller-style computer studies course in a teacher education environment are described. The motivation for, and thoughts behind, such a course are discussed. Aspects of the implementation stage are dealt with in some detail. Student performance is evaluated and supplemented by students' reactions to the course as measured by means of the semantic differential.

An index of left ventricular contraction can be extracted from the cavitary time-activity curve of electrocardiographic (ECG)-gated myocardial perfusion scans. To assess the induction of stress-induced myocardial depression, we compared contraction indexes derived from immediate poststress and delayed 201Tl images with indexes of ventricular dilation and lung uptake in the prediction of severe coronary artery disease (defined as two or more 90 stenoses). Stress procedures were performed in 93 patients with symptom-limited supine bicycle exercise alone, and in 227 with intravenous dipyridamole, combined where possible with exercise. The immediate and delayed contraction indexes reflected left ventricular dysfunction on ventriculography (P<0.0001), but additionally the immediate index was reduced (P<0.0001) in severe coronary disease. Stress-induced hypokinesis was seen frequently after each of the test modes. The relationship with angiographic findings was better defined for indexes of contraction than for lung uptake or ventricular dilation (P<0.01). The prediction of severe coronary disease was optimized by combining the poststress contraction index and lung uptake. These data support the use of ECG-gated myocardial scans in evaluating the functional consequences of stress/imaging procedures.

From 1966 to 1973, a total of 30 cases of tuberculous peritonitis were seen in Seattle-King County. Abdominal pain, swelling, and constitutional symptoms were the most frequent initial complaints. Radiographic abnormalities consistent with tuberculosis were present in 25 cases, and pulmonary disease was proven in ten. An initial tuberculin test with intermediate-strength purified protein derivative of tuberculin was negative in 19 of 27 patients. Six of 13 initial nonreactors still had negative reactions on repeat testing, and four appeared to be anergic when retested one to four months later. Ascites was present in 67 percent (20) of the 30 patients, and laparotomy was used most frequently to establish the diagnosis. Diagnosis was particularly difficult in 13 alcoholics, in whom the disease was usually unsuspected, the findings in the ascitic fluid were uncharacteristic, and negative tuberculin reactions were frequent. Peritoneal tuberculosis was a contributory cause of death in five cases. Three of these patients, who were also alcoholics, went undiagnosed and untreated. Two patients died of unrelated causes. Twenty-three have done well, and 19 have completed chemotherapy.

A model of experimental pneumococcal meningitis in rabbits is described. Animals were infected by intravenous inoculation of 107cfu of type III pneumococci immediately after withdrawal of 0.5 ml of CSF from the basal cistern. Pneumococcal meningitis, defined as CSF pleocytosis, positive cultures of the CSF, and clinical findings indicative of CNS infection 24 hr after inoculation, occurred in 54.5% of rabbits infected in this way. A higher proportion of animals, 83.9% developed meningitis if 0.5 ml of a 0.125% suspension of sterile mucin was injected into the cistern at the time of the initial tap (P= 0.025,×2). All but 2 of 54 animals with meningitis died spontaneously; the duration of survival of animals which did not receive mucin was 64.0 ± 20.8 hr (mean ± S.D.) while the animals receiving mucin survived 80.2 ± 20.1 hr (P< .001, ttest). Mucin did not otherwise alter the clinical course of animals with meningitis, and the CNS pathology was indistinguishable within the two groups, and gross and microscopic findings were similar to those of human infection.

1. Sodium transport across isolated frog skin, as measured by the short‐circuit current, was decreased by acetylsalicylic acid, mefenamic acid, paracetamol and phenylbutazone. Indomethacin (6 X 10(‐6) M) had a biphasic effect on the short‐circuit current: a transient increase followed by a sustained decrease. 2. The release of prostaglandin‐like material from the skin was reduced by acetylsalicylic acid and indomethacin. Paracetamol caused a significant reduction in the short‐circuit current response of the skin to low doses of arachidonic acid, but the response to the highest dose tested was not significantly altered. 3. Indomethacin (6 X 10(‐6) M) increased the sensitivity of the skin to applied prostaglandin E1. The other prostaglandin synthetase inhibitors did not have this effect. Indomethacin (6 X 10(‐6) M) also enhanced the effect of antidiuretic hormone on the short‐circuit current. 4. Indomethacin (30 X 10(‐6) M) increased the short‐circuit current and diminished the response to applied prostaglandin E1. 5. In sulphate Ringer, theophylline increased the short‐circuit current and diminished the response to prostaglandin E1. 6. Prostaglandin E1 increased the levels of cyclic AMP in frog skin and these increases preceded the increases in short‐circuit current. There was a seasonal variation in the level of cyclic AMP in the skin: the levels in winter exceeded those in summer. There was also a seasonal variation in the cyclic AMP response to prostaglandin E1: the winter response was greater than that in summer. 7. Indomethacin (6 X 10(‐6) M) had a biphasic effect on cyclic AMP levels in the skin, an initial increase followed by a decrease. Indomethacin also potentiated prostaglandin E1 stimulated cyclic AMP accumulation. 8. Theophylline increased cyclic AMP levels in the skin and potentiated prostaglandin E1 stimulated cyclic AMP accumulation. 9. Pre‐treatment of the skin with theophylline reversed the effects of cyclic AMP on the short‐circuit current and open‐circuit potential. 10. It is concluded that endogenous prostaglandins help to maintain sodium transport across isolated frog skin and that the effects of E‐type prostaglandins on the short‐circuit current are mediated by increased cyclic AMP levels. The transient increase in short‐circuit current and the increased skin sensitivity caused by indomethacin (6 X 10(‐6) M) are attributed to inhibition of phosphodiesterase activity. The failure of theophylline to potentiate the short‐circuit current response of the skin to prostaglandin E1 is attributed to alteration of cyclic AMP action on the skin by theophylline.

Multicellular tumour spheroids may provide a suitable in-vitromodel for micrometastases in vivo. In this paper, the results are reported of experimental studies on the radiation response of two lines of spheroids derived from human neuroblastoma. Spheroids of ~ 200–250 µM mean diameter were exposed to graded doses of X rays (50–350 cGy) and, following a static or regression phase, regrew at rates which approximated those of unirradiated spheroids. Clonogenic surviving fraction was estimated, at each dose level, by extrapolation of the regrowth curve to zero dose. It is proposed that this procedure is more suitable for regrowth curves of spheroids than in-vivotumours, because of the absence in vitro of complicating factors which occur only in vivo. By this means, survival curves were deduced and were found (for both cell lines) to be almost exponential in form, with little indication of capacity for accumulation of sublethal damage (multitarget parameters: DQ values: 17 and 25 cGy; Dovalues: 104 and 81 cGy respectively). These results contribute to the evidence for high radiosensitivity of neuroblastoma cells in vitroand provide a rationale for the use of hyperfractionation in the clinical treatment of neuroblastoma by radiotherapy.

Targeted radiotherapy consists of biologically selective irradiation of malignant cells by means of radionuclides attached to tumour-seeking molecules. A variety of clinical strategies for targeted radiotherapy may be used, for which different normal tissues will be critical. A large number of radionuclides exist, emitting nuclear particles with a range of path lengths from nanometres to millimetres.An important feature of normal-tissue radiobiology is the dose-rate effect, which is especially marked for late-responding tissues. Radiobiological calculations imply that tolerance dose for targeted radiotherapy using low-LET emitters will depend strongly on the effective half-life of the radionuclide, which will be affected by pharmacokinetics and may vary between patients. Some strategies designed to improve the therapeutic radio (e.g. accelerated clearance of radionuclide) may have modulating effects on the tolerance dose.Tumour response will be governed by the 'four Rs' (repair, repopulation, reoxygenation, redistribution) as well as by mechanisms peculiar to targeted radiotherapy. Analysis based on the extended linear quadratic model predicts that dose-rate effects will be of major importance for only a minority of tumours. Most of the radiation dose to tumour will usually be delivered over a time-scale of a few days. This might give insufficient time for tumour reoxygenation, making the use of hypoxic sensitizers appropriate. A special feature of targeted radiotherapy is the complex relationship between tumour curability and tumour size for different radionuclides. For long-range β-emitters, microscopic tumours may be operationally resistant because of inefficient absorption of radionuclide disintegration energy in small volumes. Short-range emitters will be more efficient in sterilization of micrometastases but sterilization of larger tumours may require an unattainable degree of homogeneity of radionuclide distribution. Optimal use of targeted radiotherapy may require it to be combined with external-beam irradiation or chemotherapy.Experimental studies will be necessary to investigate those features of targeted radiotherapy which differ from external-beam irradiation. Future directions may include targeted radiotherapy of minimal numbers of tumour cells detected by use of molecular probes. Such applications call for use of shortrange α-emitters and Auger emitters whose radiobiology will become increasingly important.

Abstract: 131I is the radionuclide most commonly used in biologically targeted radiotherapy at the present time. Microdosimetric analysis has shown that microtumors whose diameters are less than the β-particle maximum range absorb radiation energy inefficiently from targeted radionuclides. Micrometastases of diameters <1 mm are likely to be spared if targeted131I is used as a single modality. Because of this, combined modality therapy incorporating targeted131I, external beam total-body irradiation (TBI), and bone marrow rescue has been proposed. In this study, the minimum necessary TBI component is shown to depend on the radiosensitivity of the tumor cells. The analysis shows that the TBI component, to achieve radiocurability, increases directly with tumor radioresistance. For the most radiosensitive tumors, a whole-body TBI treatment dose 2×2 Gy is calculated to be obligatory, whereas practical tumors, the analysis implies that a TBI treatment delivery of 5×2 Gy is obligatory. In all situation, external beam TBI appears to be an essential factor in providing reasonable probability of cure of disseminated malignant disease. Reasonable prospects of tumor cure by combination strategies incorporating131I exist for the more radiosensitive tumor types (e.g., neuroblastoma, lymphoma, leukemia, myeloma, seminoma), but more resistant tumors are unlikely to be curable at present. Superior targeting agents, and the possible use of panels of different radionuclides, may be necessary to achieve high cure probabilities for less radiosensitive tumor types.

Selective uptake of radiolabelled meta-iodobenzyJguanidine (mlBG)in neuroblastoma provides a possible approach to biologically targeted radiotherapy of this disease. A mathematical model was used to predict absorbed doses to tumours of varying size from therapeutic 13lI-mIBG, based on measurements of 125I-mIBG uptake in surgically excised tumours from six patients. Two size categories of tumour target were considered: bulk tumour and microscopic disease. The predicted absorbed doses were compared with doses calculated to achieve a 50% probability of tumour cure. The analysis shows that the probability of tumour cure depends strongly on mlBG uptake, effective half-life of mlBG in tumour and tumour diameter. Small microtumours may be relatively resistant to mlBG treatment owing to the limited absorption of 131I beta-energy. The product of patient mass and percentage uptake per unit mass of tumour may be a useful indicator of therapeutic outcome when targeted radiotherapy is used for the treatment of paediatric tumours.

Neuraxis radiotherapy of radiosensitive tumours such as medulloblastoma is usually carried out using conventionally sized fractions and a shrinking field technique. Plowman and Doughty (Br. J. Radiol., 64 (1991) 603–607) have proposed a partial transmission block (PTB) technique which entails the use of small daily doses over a conventional time period. Radiobiological analysis suggests that, although the PTB technique may be adequate for slowly growing tumours, therapeutic efficacy is likely to be compromised where the tumour doubling time is short. Accelerated hyperfractionation (twice daily fractions) provides a possible alternative to both conventional scheduling and the PTB technique. Direct measurement of the kinetics of tumour cells in CSF, where possible, may provide useful guidance in the choice of regimes.

The authors present and argue their case for a new conception of the secondary mathematics teacher as a self-empowered individual. It is noted that self-empowerment constitutes a worthwhile intervention strategy for the improvement of secondary mathematics education in general. A major section describes practical illustrations of the empowered mathematics teacher in action as experienced first hand by one of the authors (English). Significant benefits for secondary mathematics education are highlighted. A functional model of empowerment is presented, one which encapsulates new insights for improving secondary mathematics education. Finally, a number of strategies aimed at implementing the proposal are explored.

A mathematical model for optimal scheduling of total-body irradiation (TBI) in the treatment of leukaemia is described. A survey of the radiosensitivities of human leukaemic cells indicate that they are highly radiosensitive with little fraction size dependence (median D0= 0.74 Gy; median Dq= 0.14Gy). These properties, when considered alongside the high repair capacity of lung, suggest that TBI schedules of the “accelerated hyperfractionation” type are optimal. The antileukaemic effects of alternative schedules, chosen to be isoeffective for lung damage to a reference schedule of 6 × 2 Gy in 3 days, were compared. A modestly hyperfractionated schedule of 10 fractions of 1.3–1.5 Gy in 5 days has theoretical advantages while retaining practicality of clinical administration.

Carcinoma of the prostate is the commonest malignancy of the genitourinary tract in the male and is frequently associated with metastatic bone disease. Serial isotope bone scans for screening secondary deposits are not cost-effective. We have evaluated the serum prostate markers prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP) as an alternative to conventional serial bone scanning in 129 patients with newly diagnosed prostate cancer over a period of 3 years. Although serum PSA did not reflect local tumour burden at presentation, it was significantly elevated in those who presented with stage D disease (p< 0.01). 45 patients presented de novowith metastatic bone deposits and a further 18 patients developed metastases during the study period. The sensitivity of PSA in detecting secondary deposits at presentation for levels in excess of 100 μg/1 was 93.75%, the positive predictive value 95.7% and the negative predictive value for levels less than 5 μg/1 was 90.6%. During the follow-up period the sensitivity was 94.4%, the positive predictive value 100% and the negative predictive value 100%, with a median lead time of 3 months in predicting metastases in the 18 patients with progressive disease. When compared with PAP, PSA was found to be a statistically superior marker of bone metastases both at presentation and follow-up (p< 0.05). We recommend that PAP measurements are no longer necessary and should be replaced by PSA, and that serial serum PSA estimations should determine the need for future isotope bone scans in the patient with established prostate cancer.

This paper presents a solution to the problem of hydrodynamic lubrication of journal bearings taking into account the elastic distortions of the shaft and the bearing. The exact solution for determining the elastic deformation for a given pressure distribution around a bearing is given, together with the reiterative procedure adopted to find the pressure distribution which satisfies both the hydrodynamic and elastic requirements of the system. Results are given which have been derived for a material with a Poisson’s ratio of 0.28, but other values such as 0.33 do not incur substantial errors. The results can be applied to a wide range of operating conditions using the nondimensional group of terms suggested in the paper. The bearing is assumed to be infinite in length, and infinite in thickness. The latter assumption is shown to be valid for a particular case where the outside diameter of the bearing shell is 3.5 times the shaft diameter. A further assumption in the calculation is a condition of constant viscosity of the lubricant existing around the bearing.