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Introduction: LGR5 positive supporting cells (SCs) in the cochlea give rise to hair cells (HCs) during embryonic development. Neonatal SCs have increased progenitor potential compared to adult and only a few studies (including ours) have shown survival of SCs with progenitor cell markers after severe HC loss in adult mice. In mammals, there is no evidence for spontaneous HC regeneration in adulthood. However, three-dimensional cultures have allowed the expansion and experimentation of human (and mouse) inner ear organoids. Here, we evaluated HC differentiation from human cochlear organoids and from adult normal-hearing and deafened mice. Material and methods: Adult patients undergoing surgery for skull base tumors were included. Sensory epithelium of the cochlea and vestibular organ was collected in medium and tissue was digested to single cell suspension. Adult Lgr5-eGFP-IRES-creERT2 heterozygous mice were used. Mice were deafened with a single dose of furosemide in combination with kanamycin and deafening was confirmed by auditory brainstem responses (ABRs). Cochleas were harvested and digested to single cell suspension and after filtering, 3D drops were made with Matrigel. Cells were grown on expansion medium (EM) for 10 days and differentiation medium (DM) for 3-10 days after. Organoids were fixed, permea-bilized and processed for immunofluorescence and whole-mounted for imaging in a confocal microscope. Results: Vestibular-organ-derived organoids were generated in EM from all seven patients so far included. Cochlea-derived organoids were generated in five out of seven patients. After exposure to DM, vestibular organ-derived and cochlea-derived organoids produced MYO7A+ HC-like cells. Cochlear organoids from normal-hearing mice expressed LGR5 and Ki67 in EM and MYO7A after differentiation. Significantly less cochlear organoids were produced from deafened mice; however the organoids reached similar size as NH-cochlear organoids, expressed LGR5 and Ki67 in EM and MYO7A after differentiation. Conclusions: Cochlear and vestibular tissue from adult patients (and adult normal-hearing and deafened mice) possess progenitor potential and the capacity to generate inner ear organoids in vitro. After differentiation, HCs were visible in tissue derived from human cochlea, human vestibular organ, and adult mouse cochlea. The adult inner ear has (limited) regenerative capacity and can produce new MYO7A+ HCs. [ABSTRACT FROM AUTHOR]

The list of EPA-approved disinfectants for coronavirus features many products for use on hard, non-porous materials. There are significantly fewer products registered for use on porous materials. Further, many common, high-touch surfaces fall in between non-porous materials such as glass and porous materials such as soft fabrics. The objective of this study was to assess the efficacy of selected commercially available disinfectant products against coronaviruses on common, high-touch surfaces. Four disinfectants (Clorox Total 360, Bleach solution, Vital Oxide, and Peroxide Multi-Surface Cleaner) were evaluated against Murine Hepatitis Virus A59 (MHV) as a surrogate coronavirus for SARS-CoV-2. MHV in cell culture medium was inoculated onto four materials: stainless steel, latex-painted drywall tape, Styrene Butadiene rubber (rubber), and bus seat fabric. Immediately (T0) or 2-hr (T2) post-inoculation, disinfectants were applied by trigger-pull or electrostatic sprayer and either held for recommended contact times (Spray only) or immediately wiped (Spray and Wipe). Recovered infectious MHV was quantified by median tissue culture infectious dose assay. Bleach solution, Clorox Total 360, and Vital Oxide were all effective (>3-log10 reduction or complete kill of infectious virus) with both the Spray Only and Spray and Wipe methods on stainless steel, rubber, and painted drywall tape when used at recommended contact times at both T0 and T2 hr. Multi-Surface Cleaner unexpectedly showed limited efficacy against MHV on stainless steel within the recommended contact time; however, it showed increased (2.3 times greater efficacy) when used in the Spray and Wipe method compared to Spray Only. The only products to achieve a 3-log10 reduction on fabric were Vital Oxide and Clorox Total 360; however, the efficacy of Vital Oxide against MHV on fabric was reduced to below 3-log10 when applied by an electrostatic sprayer compared to a trigger-pull sprayer. This study highlights the importance of considering the material, product, and application method when developing a disinfection strategy for coronaviruses on high-touch surfaces. [ABSTRACT FROM AUTHOR]

Introduction: Over 400 million people worldwide suffer from hearing loss, which requires medical intervention. The current treatments available to these patients are the use of hearing aids or cochlear implants. Although they improve the patients quality of life, 'normal' hearing is not completely restored. A primary cause of hearing loss results from damage to hair cells (HCs) due to excessive noise exposure, ageing, or the exposure to ototoxic drugs. These damaged HCs are not regenerated in humans and can continue to deteriorate with time. In non-mammalian vertebrates, supporting cells (SCs) in the cochlea have regenerative capacities and give rise to new HCs after damage, even in adulthood. Research with neonatal mice has also shown that SCs can give rise to new HCs after damage in vivo. Furthermore, neonatal SCs can be expanded and differentiated into hair cells in vitro. However, for translational purposes, it is important to evaluate if this is also possible with adult-derived tissue. Material and methods: Young adult and mature adult Lgr5GFP transgenic and C57CB/Bl6 mice were used for isolating cochleas. Cochleas were harvested and, after digestion with thermolysin and accumax, single cells were mixed with Matrigel, plated in 3D and grown in a high growth factor medium containing Wnt, R-spondin, and Noggin conditioned mediums. After passaging with trypsin and mechanical trituration, we evaluated proliferation and differentiation by immunofluorescence microscopy and qPCR or bulk sequencing. Results: Lgr5-expressing SCs derived from adult (p30-p200) Lgr5GFP transgenic and C57CB/Bl6 mice cochleas can be expanded to at least 9 passages without losing differentiation capacity. Lgr5 is highly expressed in expansion medium and lost after differentiation. Atohl expression increases during expansion and it is lost after differentiation. Myosin7 is not expressed in expansion medium and it is highly enhanced after differentiation. In parallel, we aim to setup a co-culture system where we will culture differentiated cochlear orga-noids with spiral ganglion neurons (SGN), to further mimic the in vivo physiology. This research will be the first step to building a functional primary cochlear organoid model to get a better understanding of the regenerative capacities of adult derived tissue. [ABSTRACT FROM AUTHOR]

Introduction: Radiotherapy is a mainstay of cancer therapy for a wide variety of anatomical areas. An unfortunate side effect of treatment can be radiation damage to the skin which can be a painful and debilitating problem. Previous experience from the experimental use of Flamigel® in two large-scale clinical studies on affected skin has proven sufficiently positive for the addition of a new product in the Flamigel® family (now commercially available in the UK as Flamigel RT®, Flen Health UK). The aim of this investigation is to evaluate the use of this new product to study how effective it is in the prevention and/or treatment of radiation-induced skin damage. Materials and methods: A survey was conducted among radiotherapy specialist teams in dedicated UK radiotherapy centres between 1 January 2017 and 31 October 2017. This report is of a preliminary evaluation conducted by UK-based specialists on 108 patients undergoing radiotherapy. The scoring system for skin reactions of the 'Radiation Therapy Oncology Group' was used. Results: Results show that the use of Flamigel® has the potential to soothe (p = 0·0001), reduce pain (p = 0·0001) and reduce pruritus (p = 0·004). The product met the expectations of the clinicians involved (p < 0·0001) of whom most were happy to continue use or to recommend its use to colleagues (p < 0·0001). Conclusions: Flamigel® is an effective treatment in the management of radiation-induced skin reactions. Erythema was unchanged through the study period (p = 0·42). No adverse reactions were reported after the use of Flamigel from twice to six times a day. [ABSTRACT FROM AUTHOR]

This paper presents a framework for generating multi-layer, unconditional soil profiles with complex stratigraphy, which simulates the effects of natural erosion and sedimentation processes. The stratigraphy can have varying degrees of randomness and can include features such as lenses, as well as sloped and undulating layers. The method generates the soil comprising the layers using local average subdivision (LAS), and a random noise component that is added to the layer boundaries. The layers are created by generating coordinates of key points in the simulated ground profile, which are then interpolated with a customised, 2D, linear interpolation algorithm. The resulting simulations facilitate more accurate probabilistic modelling of geotechnical engineering systems because they provide more realistic geologies, such as those usually encountered in the ground. Fortran code implementing this framework is included as supplementary material. [ABSTRACT FROM AUTHOR]

This note investigates the reliability of undrained slopes by the random finite-element method. The focus of this note is on the worst-case spatial correlation length, namely the correlation length at which the probability of slope failure reaches a maximum. It is shown that the worst-case phenomenon is most pronounced when the mean factor of safety is relatively low or the coefficient of variation is relatively high. Knowledge of the worst-case spatial correlation length is valuable, as it can be employed for conservative design in the absence of substantial soil field data. [ABSTRACT FROM AUTHOR]

Natural discontinuities are known to play a key role in the stability of rock masses. However, it is a non-trivial task to estimate the shear strength of large discontinuities. Because of the inherent complexity to access to the full surface of the large in situ discontinuities, researchers or engineers tend to work on small-scale specimens. As a consequence, the results are often plagued by the well-known scale effect. A new approach is here proposed to predict shear strength of discontinuities. This approach has the potential to avoid the scale effect. The rationale of the approach is as follows: a major parameter that governs the shear strength of a discontinuity within a rock mass is roughness, which can be accounted for by surveying the discontinuity surface. However, this is typically not possible for discontinuities contained within the rock mass where only traces are visible. For natural surfaces, it can be assumed that traces are, to some extent, representative of the surface. It is here proposed to use the available 2D information (from a visible trace, referred to as a seed trace) and a random field model to create a large number of synthetic surfaces (3D data sets). The shear strength of each synthetic surface can then be estimated using a semi-analytical model. By using a large number of synthetic surfaces and a Monte Carlo strategy, a meaningful shear strength distribution can be obtained. This paper presents the validation of the semi-analytical mechanistic model required to support the new approach for prediction of discontinuity shear strength. The model can predict both peak and residual shear strength. The second part of the paper lays the foundation of a random field model to support the creation of synthetic surfaces having statistical properties in line with those of the data of the seed trace. The paper concludes that it is possible to obtain a reasonable estimate of peak and residual shear strength of the discontinuities tested from the information from a single trace, without having access to the whole surface. [ABSTRACT FROM AUTHOR]

Based on recently published deterministic solutions as a benchmark, the random finite-element method is used here to investigate the influence of spatial variability on the undrained stability of normally consolidated random slopes, where the mean strength increases linearly with depth while the coefficient of variation remains constant. Results are presented in the form of charts that give the mean and standard deviation of a dimensionless stability number. Using the charts presented in this note, engineers can obtain a preliminarily assessment of the probability of failure of normally consolidated clay slopes. [ABSTRACT FROM AUTHOR]

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Background and Purpose: Prostanoid EP(4) receptor antagonists may have therapeutic utility in the treatment of migraine since EP(4) receptors have been shown to be involved in prostaglandin (PG)E(2)-induced cerebral vascular dilatation, which may be an important contributor to migraine pain. This study reports the pharmacological characterization of BGC20-1531, a novel EP(4) receptor antagonist.Experimental Approach: BGC20-1531 was characterized in radioligand binding and in vitro functional assays employing recombinant and native EP(4) receptors. Changes in canine carotid haemodynamics were used to assess the pharmacodynamic profile of BGC20-1531 in vivo.Key Results: BGC20-1531 exhibited high affinity at recombinant human EP(4) receptors expressed in cell lines (pK(B) 7.6) and native EP(4) receptors in human cerebral and meningeal artery (pK(B) 7.6-7.8) but showed no appreciable affinity at a wide range of other receptors (including other prostanoid receptors), channels, transporters and enzymes (pKi < 5). BGC20-1531 competitively antagonized PGE(2)-induced vasodilatation of human middle cerebral (pK(B) 7.8) and meningeal (pK(B) 7.6) arteries in vitro, but had no effect on responses induced by PGE(2) on coronary, pulmonary or renal arteries in vitro. BGC20-1531 (1-10 mg.kg(-1) i.v.) caused a dose-dependent antagonism of the PGE(2)-induced increase in canine carotid blood flow in vivo.Conclusions and Implications: BGC20-1531 is a potent and selective antagonist at EP(4) receptors in vitro and in vivo, with the potential to alleviate the symptoms of migraine that result from cerebral vasodilatation. BGC20-1531 is currently in clinical development for the treatment of migraine headache. [ABSTRACT FROM AUTHOR]

Copyright of Géotechnique is the property of Thomas Telford Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose -- The paper sought to clarify the concept of learning organisation/community; to identify the barriers that are perceived to obstruct the creation of learning communities out of traditional schools; to identify how principals go about the task of converting their schools; and the special characteristics of leadership required to transform schools successfully. Design/methodology/approach -- The study was dependent on an extensive review of the literature and generated data from structured interviews of principals from the New South Wales (Australia) public education system. Findings -- Respondents lacked a clear understanding of a learning organisation despite their actions to implement the concept in their own schools; the concept may indeed be too abstract to enable a suitable workable definition; there is, nevertheless, a strong belief that the concept has much to offer; leadership is the key factor in transforming schools; and traditional school structures and cultures, lack of implementation time, and difficulty in obtaining the support of staff and parents are seen as the main barriers to implementation. Originality/value -- The paper explores extensively the possible implications of the study and addresses these to schools and school systems, principals, teachers and parents. [ABSTRACT FROM AUTHOR]

Copyright of Géotechnique is the property of Thomas Telford Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary The purpose of this study was to examine the effects of an external nasal strip (NS), frusemide (FR) and a combination of the 2 treatments (NS + FR) on exercise-induced pulmonary haemorrhage (EIPH) in Thoroughbred horses. It was hypothesised that both the NS and FR would attenuate EIPH as assessed by red blood cell count in bronchoalveolar lavage fluid. In random order, 8 horses completed each of 4 sprint exercise tests on a treadmill: 1) NS; 2) FR (0.5 mg/kg bwt i.v., 4 h pre-exercise); 3) NS + FR; and 4) control (C; no treatment). After a 5 min warm-up (4.5 m/s), horses completed 2 min running at 120% maximum oxygen consumption (V [ABSTRACT FROM AUTHOR]

Describes the brood duration and marsupial development of three temperate coastal mysid species, Anisomysis mixta australis, Tenagomysis tasmaniae, and Paramesopodopsis rufa, found commonly in Tasmanian waters. Brood durations of larvae cultured in vitro; Materials and methodology used for the study; Results of the study; Discussion and conclusion of the study.

Otolith increment age estimates for a deepwater species, Allocyttus verrucosus, were validated by comparison with the results from Pb:Ra radiometric analysis. Transverse sectioning and subsequent grinding of otoliths to a thickness of ≃ 0.2 mm revealed increments which provided age estimates for a range of fish sizes. Age estimates ranged from 7 yr for an immature fish of 15.2 cm total length (TL) to 130 yr for a female fish of 36.5 cm TL. Age at maturity was estimated as 28 yr for females and 24 yr for males. In comparison, radiometric analysis of whole otoliths, using a single linear otolith-mass growth-rate model suggested maximum ages of 130 to 170 yr for fish of 34 to 35 cm TL. Radiometric ages were also recalculated using a two-phase otolith-mass growth-rate model in which the growth rate was assumed to slow after maturity to 90% of the pre-maturity rate. This reduced the maximum age to 132±15 yr for a mean fish length of 34.5 cm. Age at maturity for females was estimated at 34 yr. The similarity between age estimates from otolith-increment counts and radiometric analysis strongly supports the accuracy of results from both methods, and encourages further use of such comparisons as an alternative to traditional validation techniques. [ABSTRACT FROM AUTHOR]

Background: Twenty-six young men admitted to an Accident and Emergency Department for observation following a minor closed head injury (post-traumatic amnesia (PTA) less than 12 hours) were investigated within 24 hours of admission (day 0) and followed up at 10 days, 6 weeks and 1 year after the trauma.Method: Investigations at day 0 included physical examination, completion of post-concussional symptom and stress-arousal checklists, computerised EEG (CEEG) and auditory brainstem evoked potential (BAEP) recordings. These were repeated at ten days and six weeks. At 12 months follow-up, the Present State Examination (PSE) was carried out and a further post-concussional symptom checklist completed.Results: Post-concussional symptomatology declined progressively from day 0 but half had residual symptoms at 1 year. Seventy-two per cent ran an acute course with recovery by 6 weeks, 8% chronic unremitting course and 20% initially improved but had an exacerbation of symptoms between 6 weeks and 12 months. The CEEG alpha-theta ratios decreased significantly between days 0 and 10, reaching a baseline thereafter. Measures of CEEG recovery from all channels correlated with symptom counts at six weeks; the slower the recovery the greater the symptoms. A relative delay in left temporal recovery was associated with residual psychiatric morbidity (PSE ID scores) at 12 months. Prolonged central brainstem conduction times occurred in 27% of patients at day 0. These correlated positively with PTA and degree of psychiatric morbidity (PSE ID scores) at 12 months.Conclusions: Symptom chronicity was accompanied by continuing brainstem dysfunction, while the degree of transient cortical dysfunction appeared to have a direct influence in the intensity of early organic symptom reaction to the trauma. Levels of perceived stress at the time of the injury, or afterwards, were not related to symptom formation. [ABSTRACT FROM AUTHOR]

Background: We test the hypotheses that (a) cognitive therapy is of comparable efficacy to psychodynamic psychotherapy, (b) 8-10 sessions of therapy is as effective as 16-20 sessions, and (c) brief therapist training is as effective as intensive training.Method: Of 178 out-patients referred to a clinical trial of psychological treatment for generalised anxiety, 110 patients met DSM-III-R criteria for generalised anxiety disorder and were randomly assigned to three different forms of psychotherapy. The main comparison was between cognitive therapy and analytic psychotherapy, delivered by experienced therapists at weekly or fortnightly intervals over six months. A third treatment, anxiety management training, was delivered at fortnightly intervals by registrars in psychiatry after a brief period of training. Eighty patients completed treatment and were assessed before treatment, after treatment, and at six-month follow-up.Results: Cognitive therapy was significantly more effective than analytic psychotherapy, with about 50% of patients considerably better at follow-up. Analytic psychotherapy gave significant improvement but to a lesser degree than cognitive therapy. There was no significant effect for level of contact. Patients receiving anxiety management training showed similar improvements to cognitive therapy after treatment, with rather lower proportions showing clinically significant change.Conclusions: Cognitive therapy is likely to be more effective than psychodynamic psychotherapy with chronically anxious patients. Significant improvements in symptoms can be achieved by trainee psychiatrists after only brief instruction in behaviourally based anxiety management. However, the superiority of cognitive therapy at follow-up suggests that the greater investment of resources required for this approach is likely to pay off in terms of more sustained improvement. There is no evidence that 16-20 sessions of treatment is more effective, on average, than 8-10 sessions. [ABSTRACT FROM AUTHOR]

The study consisted of a prospective investigation of 45 consecutively admitted patients who had sustained a mild head injury. In all cases the duration of post-traumatic amnesia was less than 24 hours. Head injury patients had an average of three adverse life events in the year preceding injury compared with 1.5 for controls. Using the PSE, 39% of the group were diagnosed psychiatric cases at six weeks after the injury. For cases the mean level of chronic social difficulties (3.3) was four times that for non-cases (0.8). Six months after injury, 28% of the head injury group had three or more symptoms. These chronic cases were on average ten years older than those whose symptoms had remitted. Chronic cases had, on average, three social difficulties, twice as many as found among those whose symptoms had remitted. The emergence and persistence of the postconcussional syndrome are associated with social adversity before the accident. While young men are most at risk of minor head injury, older women are most at risk of chronic sequelae. [ABSTRACT FROM AUTHOR]

The article presents a study on the characteristics of hysteroepilepsy. The term implies brain mechanisms in common between epilepsy and hysteria wherein no such direct link between these two conditions exists. However, there are a number of indirect associations between epilepsy and hysteria that could lead to confusion in the differential diagnosis and management of the patient. Hysterical psuedoseizures are attacks are attacks of sudden unconsciousness, usually associated with dramatic motor manifestations.

Using a classical click/flash paradigm the contingent negative variation (CNV) was recorded from 60 consecutive male admissions to Broadmoor Hospital. Clinical and psychometric Minnesota Multiphasic Personality Inventory (MMPI) assessments were made independently of the electroencephalography (EEG) data. A trend for higher amplitude CNV's to be recorded from patients with a clinical diagnosis of antisocial (psychopathic) personality was observed. Patients with a Mental Health Act diagnosis of psychopathic disorder had significantly higher voltage CNV's than those in the mental illness category. These CNV differences were only found in the primary (non-anxious, sociable) psychopaths. Secondary (neurotic, unsociable) psychopaths did not differ from staff controls. A positive association between CNV voltage and the personality factor of sociability(sociable-shy dimension) was observed. A weak, negative correlation between CNV amplitude and impulsivity (impulsive-controlled dimension) was also apparent. All subjects showed an habituation effect across trials. No difference in response variability between successive series of trials was apparent in any of the patient groups. [ABSTRACT FROM AUTHOR]

An analysis of a reinforced masonry flexural testing program carried out at Carleton University is presented with data obtained from other published sources. Practical design relationships are proposed in keeping with the current limit state design philosophy to deal with flexural capacity and minimum and maximum reinforcement ratios. [ABSTRACT FROM AUTHOR]

Four channels of EEG (T4-T6, P4-02, T3-T5, P3-01) were recorded from several groups of control subjects and schizophrenia patients on analogue tape. They were later digitized and analysed by computer; power spectra were computed for 30 second epochs of EEG per channel; eyes closed, eyes open. No difference between normal controls and neurotic in-patients was apparent. An acute schizophrenic group had less alpha power, this change being confined largely to the temporal areas. A chronic outpatient sample showed less alpha and beta power, while chronic long-stay schizophrenic patients had an excess of delta power. The changes in both chronic patient groups were diffuse rather than local. [ABSTRACT FROM AUTHOR]

Using a classical click/flash paradigm, the CNV was recorded from the following three groups of subjects at Broadmoor Hospital: (1) 14 'psychopathic' patients selected by use of the 4/9 MMPI profile and confirmed by independent clinical diagnosis; (2) 15 'non psychopathic' patients, all psychotic and mainly schizophrenic; (3) 14 healthy staff control subjects. All three groups were matched for age and sex; the two patients groups were also matched for length of stay. Two series of 32 paired stimuli were used, separated by an interval of 30 minutes. The mean CNV voltage was significantly lower in the 'non-psychopathic' patients. The amplitude of the 'psychopath's' CNV response did not differ significantly from that of the staff controls, but the response variability between the first and second series of trials was much greater in the 'psychopathic' patients than in the other two subject groups. The 'psychopathic' subjects tended to show more rapid initial development of the CNV. [ABSTRACT FROM AUTHOR]

The article cites a study that analyzes a group of 178 male patients who are admitted to Broadmoor Hospital in England, and differentiates and contrasts findings with those of an earlier research on offender patients in an area mental hospital. Broadmoor Hospital is one of the three Special Hospitals designed for the treatment of patients of dangerous or violent propensities. Several tables are presented which differentiate the Broadmoor group and groups of non-offender patients and offender patients. A relative excess of schizophrenic illness is diagnosed in both offender patient groups, while psychopathic disorders are common in Broadmoor patients. More similarities are observed between the 2 offender patient groups. Fewer Broadmoor patients are found to have previous hospital admissions.

Focuses on the introduction of an electrocardiogram (ECG) compression algorithm which was based on a combination of the Karhunen-Loeve transform (KLT) and multirate sampling. What is reduced by multirate sampling; Details on what the ECG is used for; Basis of the ECG recording for clinical use.

A four-choice reaction time test was carried out on 45 minor head injury cases, 24 hours after the injury and 6 weeks later. Twenty-eight subjects were re-tested after a six month interval. Reaction time measures were also obtained in a matched, general practice control group. The concussion cases displayed significantly poorer performances than the matched controls in four measures, at day 0 and at 6 weeks. The patients also showed serial improvement in these measures up to six months after the injury, when their scores excelled those of the matched controls. [ABSTRACT FROM AUTHOR]

Describes a study which investigated the relationship between the vision and five dimensions of leadership behaviour of principals in Hong Kong. A survey was carried out on 48 secondary schools involving 548 teachers. Half of the sample schools wer e in a pilot scheme of school-based management, the school management initiative (SMI). Factor analysis and multiple regression were used to analyse the data. The results suggested that five dimensions of leadership behaviour were all significantly relat ed to the vision of principals for both types of schools. Whether the school was participating in the SMI or not also had a significant effect on the relationship between the vision of principals and three dimensions of leadership behaviour. Contrary to the expectations of the SMI and the suggestions by some researchers that teachers need to be particularly empowered in schools undergoing reforms, the findings of this study demonstrated that for principals with average and below average scores on vision , the degree of empowerment perceived by teachers in schools under the SMI was lower than for schools not under the reform. However, principals with high vision in schools under the reform had the highest scores in all five dimensions of leadership behav iour. The SMI may provide opportunities for leaders with vision to bring about a better environment for school improvement. These results provide important insights for those responsible for the implementation and evaluation of the SMI in Hong Kong, and perhaps for other systems devolving decision-making power to more self-managing schools. [ABSTRACT FROM AUTHOR]

Addresses the persistent tension that exists between centralized, as opposed to decentralized (devolved), structures of school governance. Examines the claims made in the literature for the positive benefits of devolution and conversely for its neg ative outcomes, and proposes some more realistic expectations. Focuses on the relationship between devolution and improved teaching and learning. Contributes to future research by providing a detailed analysis of the meaning of devolution and proposes a preliminary research paradigm with a special focus on the variables likely to have a direct effect on student learning outcomes. Calls for a co-ordinated international programme of research into the effects of devolution under the leadership of the Commo nwealth Council of Educational Administration [ABSTRACT FROM AUTHOR]