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Objectives: To investigate the prevalence of urinary incontinence in Team England female athletes participating in the 2018 Commonwealth Games, the self-imposed lifestyle modifications used to manage symptoms in training and competition and the impact on performance., Study Design: This was a Cross-Sectional Survey. All Team England female athletes participating in 2018 Commonwealth Games were asked to complete a structured questionnaire regarding symptoms and management of urinary incontinence. Chi-squared statistical analysis was applied to relevant data., Results: 103 athletes were included. 52 % reported experiencing urinary incontinence (38 % in training vs 27 % in competition X 2  = 2.68, p0.13). Highest rates of incontinence were seen in cycling and gymnastics, with lowest rates of incontinence in swimming and rugby. In sports requiring form fitting garments, 64 % did not feel they could wear a pad in training, compared with 19 % in sports with less form-fitting clothing. In competition, 75 % of athletes wearing form-fitting clothing did not feel they could wear a pad, compared with 24 % of those with less form-fitting attire (X 2  = 16.9, p < 0.001 in training; X 2  = 24.04, p = <0.001 in competition). 11 % of athletes reported reducing fluid intake to reduce urinary incontinence in training and 8 % reported doing this in competition. Only 3 % of athletes reported that their performance is affected by urinary incontinence., Conclusion: Prevalence of urinary incontinence is higher in athletes than in the general population. Tight-fitting sportswear is a barrier to athletes using pads to manage urinary incontinence. Athletes may reduce fluid intake to reduce urinary leakage in training and competition, which may affect performance. However, few athletes report that urinary incontinence has an impact overall., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Throughout the wheat-growing regions of Australia, chilling temperatures below 2 °C occur periodically on consecutive nights during the period of floral development in spring wheat (Triticum aestivum L.). In this study, wheat plants showed significant reductions in fertility when exposed to prolonged chilling temperatures in controlled environment experiments. Among the cultivars tested, the Australian cultivars Kite and Hartog had among the lowest levels of seed set due to chilling and their responses were investigated further. The developmental stage at exposure, the chilling temperature and length of exposure all influenced the level of sterility. The early period of booting, and specifically the +4 cm auricle distance class, was the most sensitive and corresponded to meiosis within the anthers. The response of microtubules to chilling during meiosis in Hartog was monitored, but there was little difference between chilled and control plants. Other abnormalities, such as plasmolysis and cytomixis increased in frequency, were associated with death of developing pollen cells, and could contribute to loss of fertility. The potential for an above-zero chilling sensitivity in Australian spring wheat varieties could have implications for exploring the tolerance of wheat flower development to chilling and freezing conditions in the field., (© 2014 John Wiley & Sons Ltd.)

At excitatory synapses, decreases in cleft [Ca] arising from activity-dependent transmembrane Ca flux reduce the probability of subsequent transmitter release. Intense neural activity, induced by physiological and pathological stimuli, disturb the external microenvironment reducing extracellular [Ca] ([Ca](o)) and thus may impair neurotransmission. Increases in [Ca](o) activate the extracellular calcium sensing receptor (CaSR) which in turn inhibits nonselective cation channels at the majority of cortical nerve terminals. This pathway may modulate synaptic transmission by attenuating the impact of decreases in [Ca](o) on synaptic transmission. Using patch-clamp recording from isolated cortical terminals, cortical neuronal pairs and isolated neuronal soma we examined the modulation of synaptic transmission by CaSR. EPSCs were increased on average by 88% in reduced affinity CaSR-mutant (CaSR(-/-)) neurons compared with wild-type. Variance-mean analysis indicates that the enhanced synaptic transmission was due largely to an increase in average probability of release (0.27 vs 0.46 for wild-type vs CaSR(-/-) pairs) with little change in quantal size (23 +/- 4 pA vs 22 +/- 4 pA) or number of release sites (11 vs 13). In addition, the CaSR agonist spermidine reduced synaptic transmission and increased paired-pulse depression at physiological [Ca](o). Spermidine did not affect quantal size, consistent with a presynaptic mechanism of action, nor did it affect voltage-activated Ca channel currents. In summary, reduced CaSR function enhanced synaptic transmission and CaSR stimulation had the opposite effect. Thus CaSR provides a mechanism that may compensate for the fall in release probability that accompanies decreases in [Ca](o).

The branching pattern of the conducting airways is significantly asymmetrical in the human, and even more so in other species. Although this asymmetry is believed to have an important effect on air flow and other transport processes in the bronchial tree, both experimental and theoretical studies have predominantly employed symmetrical model bifurcations. In this paper, published morphometric data for four species (human, dog, rat and hamster) is used to calculate the frequencies with which different degrees of asymmetry occur, and to examine the relationships between four of its manifestations, asymmetry of the cross-sectional areas, the lengths, the branching angles and the flow rates of the daughter branches. The observed characteristics are compared with some of the theoretical 'branching laws' which have been proposed. Quantification of the correlations between the different manifestations of asymmetry allows the geometrical characteristics to be specified for a range of realistic asymmetrical bifurcations, for use in either theoretical or experimental studies of transport in the bronchial tree.

A diameter-based classification technique, which we have previously used to analyse human bronchial geometry (Phillips et al., Respir. Physiol. 98: 193-217, 1994) is applied also to the partial measurements of the dimensions of dog, rat and hamster conducting airways, made by Raabe et al. (Tracheobronchial Geometry: Human, Dog, Rat, Hamster, 1976). The local branching patterns are characterised by means of three parameters, which reflect the asymmetry and the degree of expansion at each bifurcation, and the ratio of the length of each branch to its diameter. The mean values of these parameters as functions of diameter, calculated from the raw morphometric data, are shown for the four species. A statistical reconstruction technique is then used to estimate from the incomplete measurements of Raabe and coworkers some geometrical properties of the whole system of conducting airways, which are likely to influence transport processes in the lung. These include the distribution of the total airway volume between branches of different diameters, the mean and variance of the total lengths of different pathways through the bronchial tree, and a simple model for the variation of flow velocity with airway diameter. Our results show significant differences between the branching structures of all four species. In particular, the human differs from the others in branching much more symmetrically, and in that branches of a given diameter are typically much longer than in the other species; together, these observations imply that the human bronchial tree is geometrically very different from those of the other species.

We propose an analysis of the branching pattern of the conducting airways of the human bronchial tree, based on classifying airways by diameter rather than by some essentially topological measure of their position in the whole lung. A diameter-based statistical reconstruction technique is applied to the partial measurements of airway dimensions made by Raabe et al. (1976), to quantify some aspects of bronchial geometry likely to influence transport processes in the lung. We give predictions for the total number of airways with each diameter, and for the partitioning of the total bronchial wall area and airway volume between airways of different diameters. We also consider the variability of the lengths of different pathways through the bronchial tree, and using a simple model for the distribution of air flow in the lung, we predict how the average flow velocity depends on airway diameter. Comparison of these results with equivalent predictions derived from Weibel's symmetrical lung model shows qualitative differences, which probably result from Weibel's use of extrapolation techniques to compensate for the lack of data on smaller conducting airways. Comparison with the predictions of Horsfield and Cumming's asymmetrical lung model shows generally good agreement, although there are significant differences relating to the asymmetry of bifurcations and to the diameter-dependence of the flow velocity in the smallest conducting airways.

In this paper we present the mathematical details of the diameter-based reconstruction technique used in the companion paper (Phillips et al., 1994 - referred to below as Part I) to analyse the morphometric data of Raabe et al. (1976) on the human bronchial tree. In the first section we outline the technique as applied to the incomplete set of measurements in order to estimate properties of the bronchial tree as a whole; in the second section we consider what form these properties would take if the bronchial tree were geometrically self-similar, as has often been assumed to be approximately the case.

A mathematical model for steady flow through a discontinuity in the tight junction of an endothelial intercellular cleft is presented. Subject to plausible assumptions the problem of calculating the flow in the cleft, in either the presence or the absence of a fibre matrix, reduces to the solution of Laplace's equation in a two-dimensional domain. For an idealized geometry representing a discontinuity between two semi-infinite tight junction regions, a general analytic solution is found by means of conformal mappings. The model geometry, unlike those assumed in previous studies, allows the tight junction regions to be out of alignment with each other, and even to overlap, modelling flow through a tortuous, rather than a direct, pathway. Useful asymptotic approximations for the flow rate are derived when the discontinuity is either very small or very large. For small discontinuities, the predicted flow rate is much greater than a naïve estimate based on uniform parallel flow through the discontinuity. For the special case where the tight junction regions are aligned with each other, comparison of our results with those of an approximate treatment due to Tsay et al. [Chem. Engng Commun. 82, 67-102 (1989)] shows generally very close agreement.

Analysis of the actions of electric currents on excitable membranes has contributed greatly to our biophysical understanding of the initiation and transmission of impulses in nerve and muscle. The use of electrical stimulation in trying to unravel the complex structure and to understand the integrative properties of the central nervous system (CNS), however, raises problems of a different order. This is true of the application of electrical stimuli to mixed populations of axons in peripheral nerves in attempts to discover the central actions of inputs from the different receptive fields, from skin, for example, or muscle or joint. But the most complex problems of all are those raised by the application of electrical stimuli to the CNS itself, whether to try to find out how it works, or to try to relieve a patient's disabilities. We would like to be able to specify, for any particular configuration of external electrodes, which populations of neurones and axons will be excited by virtue of appropriate orientation with respect to lines of current flowing cathodally within the non-isotropic conducting medium of the CNS. We would also like to know the quantities and locations of the brief excitatory and inhibitory synaptic actions, and the longer-term 'modulating' actions, which they exert at nearby and remote areas of the brain and spinal cord. In man, much could be accomplished by attentive neurological examinations, comparing sensory, motor and autonomic functions in the presence and absence of chronic stimulation, and correlating particular physiological effects with alterations of particular symptoms. Such examination would invoke all the technical resources of clinical neurophysiology. Direct evidence of the stimulation of particular spinal pathways and neurones, and of the distribution of remote excitatory and inhibitory effects, could be obtained only by multiple electrical recordings from brain and cord in animal experiments.

The pattern of Ia-connections to motor nuclei of 17 hindlimb muscles (or groups of muscles) has been investigated in baboons by intracellular recording of Ia-e.ps.p.s evoked in motoneurons from different muscle nerves. The amplitudes are normalized to 70 mV resting potential and compared with similarly normalized Ia-e.ps.p.s in cats. As in the cat, Ia-excitation is drawn from a restricted number of muscles and the homonymous effect is usually dominating. Heteronymous connections to many motor nuclei are different in the two species. For example, hip extensors are generally more Ia-isolated from each other in baboons than in cats, and also knee flexors have fewer Ia-interconnections than in cats. A unidirectional Ia-synergism between some hip extensors and knee flexors in cats has changed to a bidirectional one in baboons, with a tendency to lateralization of the connections. Among ankle extensors, soleus has smaller heteronymous Ia-connections from its synergic ankle extensors than in cats. In baboons, plantaris is heteronymously Ia-excited from gastrocnemius-soleus but not from the intrinsic plantar muscles; whereas in cats there exists a considerable Ia-projection from the intrinsic plantar muscles but not from gastrocnemius-soleus. There is a corresponding difference in the insertion of the plantaris tendon, which shows that this muscle acts as toe extensor in cats but as ankle extensor in baboons. For most of the motor nuclei, the homonymous as well as the total aggregate of Ia-e.ps.p.s is smaller in the baboon than in the cat; but the amplitude range between different motor nuclei is larger in the baboon. Reciprocal Ia-i.ps.p.s are evoked only after spinal transection or when brain function is depressed. It is postulated that baboons, contrary to cats, have descending tonic inhibition of transmission in the reciprocal Ia-inhibitory pathway. The phylogenetic flexibility of Ia-connections is discussed and contrasted with their ontogenetic stability.

J.E. Purkynĕ was the first to discover, by achromatic microscopy of stained and fixed as well as of fresh material, that animal tissues in general, and those of the central nervous system in particular, are made up of cells, as are those of plants. His discoveries laid the foundations of modern research on the ultrastructure and biophysies of the cerebellar neurons which bear his name, as well as on other types of neurons, in vitro as well as in vivo.

The posterior wall of the central sulcus in forelimb area of SI has been expolred with extracellular micro-electrodes in baboons lightyl anaesthetized with nitrous oxide and sodium thiopentone. 2. The excitatory responses of 130 single units to low intensity electrical stimulation of the deep radial (muscle) and the superficial radial (cutaneous) nerves have been investigated. 3. Units that responded only to muscle nerve stimulation were located in area 3a but overlapped into area 3b. Units that responded only to cutaneous nerve stimulation were found mainly in area 3b but a number occurred in area 3a. Units that responded to both muscle and nerve stimuli (convergent units) were found throughout area 3a and the rostral part of area 3b. 4. Latency analyses of all three response groups revealed a single population of units responding to low threshold muscle nerve stimulation (mean latency 8.5 msec), and both early and late populations responding to low threshold cutaneous nerve stimulation (mean latencies 9.5 and 13.6 msec respectively). A number of the convergent units had very similar latencies for both inputs. 5. Electrical stimulation within area 3a deminstrated a projection from areas 1 and 3b to area 3a; such a pathway may provide a route for excitation of the late skin population which was found mainly in area 3a. 6. In area 3a units commonly responded to light touch, local pressure or deep pressure but only rarely to movement of hairs. A number of the convergent units responded to natural stimulation of cutaneous receptors.

The neocortical motor areas of monkeys were discovered by epicortical electrical stimulation. Ferrier in 1875 drew non-overlapping circles for face, limbs and tail. His 'centres' were postcentral as well as precentral. In the 1880s Horsley added an arm and face area on the medical surface (where Penfield's supplementary motor area is now ensconced). At the turn of the century the newborn science of cortical architectonics discovered striking differences between precentral and postcentral areas. Sherrington got no responses from the postcentral gyrus of apes. At mid-century, however, Woolsey reinstated the postcentral motor map (his Sm 1). The discrepancies between these classical maps could probably be explained by sensitivity to levels of anaesthesia and to arbitrarily chosen configurations of stimuli whose intracortical actions remained obscure. Some of the modes of action of epicortical stimulation have since been worked out. These are relevant to the results of electrical and magnetic stimulation of the human brain through scalp and skull. Today's research is differentiating the functions of the precentral and postcentral areas (4, 6PM, 6SMA, 3a, 3b, 1): at the microscopic level, by studies of sampled neurons whose discharges can be related to specific components of learnt motor performances, and whose connectivities can be traced by electroanatomical and microscopical labelling of their perikarya, axons and synapses; at the macroscopic level, by studies of Bereitschaftspotential and regional cerebral metabolism in motor performances in intact humans.

At a famous meeting of the International Medical Congress held in London on August 4, 1881 Goltz of Strassburg (as it was then spelt) confronted Ferrier of London on the subject of the localization of function in the cerebral cortex. In the first part of this paper the events of that meeting are recalled. Goltz was reluctant to accept the idea of localization because of the restitution of function after injury to the cortex, and because of the general rather than specific residual disabilities of his lesioned dogs. On the other hand, Ferrier's monkeys with cortical lesions demonstrated convincingly that local lesions can produce loss of specific functions. One hundred years later a meeting was held in Oxford on the same topic, and the discussions that took place are summarized in the second part of this paper. No-one doubted the doctrine of localization, namely that different parts of the cerebral cortex normally perform different specialized roles. However, there was no unanimity about how to separate or count the number of different parts of the cortex, nor about the nature of the specialized roles of the parts, nor about any common characteristics of the functions of different parts. In other words, though localization was agreed upon, precisely what the functions are that are localized remained obscure. The third section of this paper advances some speculations on this point. Is a theory of cortical function that would encompass the diverse roles of different parts perhaps within sight, which might even explain the plasticity that must underlie the restitution of function that so impressed Goltz one hundred years ago?

1. Much current thinking about voluntary movement assumes that the segmental gamma loops can function as a servomechanism operated by the brain. However, the alpha motoneurones of the baboon's hand receive a powerful monosynaptic (CM) projection from the precentral gyrus. If servo-driving from the same cortical area is to be possible, it must project independently to the fusimotor neurones and have sufficient power to increase the afferent signalling from the muscle spindles. The cortical thresholds for contraction of m. extensor digitorum communis and for acceleration of the discharges of its muscle spindles have therefore been compared.2. Significant results in this context require that the spindles studied be coupled in parallel with the responding extrafusal muscle fibres. Many spindles were not unloaded by the submaximal contractions evoked by cortical stimulation, although all so tested were unloaded by maximal motor nerve twitches. Reasons are given for thinking that such apparent lack of parallel coupling is an artifact of complex intramuscular anatomy and limitation of shortening by ;isometric' myography.3. A brief burst of corticospinal volleys at 500/sec, which is specially effective in exciting alpha motoneurones over the CM projection, failed to excite spindle afferents at or below the threshold for a cortical ;twitch'.4. In a few epileptiform discharges, bursts of spindle acceleration occurred independently of the clonic contractions. A relatively direct and independent cortico-fusimotor (CF) projection may therefore exist.5. Prolonged near-threshold stimulation at 50-100/sec, which allows time for temporal summation in the less direct projections (e.g. cortico-interneuronal, cortico-rubro-spinal) and does not cause frequency-potentiation at CM synapses, gives abundant evidence of independent alpha and fusimotor projections, whose actions hardly outlast the stimulation period.6. Although independent CF projections would permit servo-driving in natural movements of the hand (given adequate loop gain), there has been no evidence of servo-driving by cortical stimulation or in the spontaneous contractions of light anaesthesia.7. Independent projections would provide for controlled alphagamma co-excitation in the servo-governing of natural movements (Matthews, 1964).8. Evidence is reviewed that the CM projection itself may be part of an important control loop for voluntary movement in primates. A corollary would be a diminished importance of CF projections for segmental loops and an increased importance for maintaining the spindle input to cortical loops.

1. The precentral and postcentral banks of the Rolandic fissure of the arm area of the baboon's cortex have been probed to their depths with extracellular micro-electrodes under nitrous oxide and oxygen anaesthesia, supplemented by minimal intravenous pentobarbitone or chloralose.2. Afferent volleys were sent in from the deep (motor) radial nerve and the deep palmar (motor) branch of the ulnar nerve. Their entry into the central nervous system was timed at the dorsal root entry zone. The nerves were stimulated in continuity and the effects of stimuli below threshold for the motor axons were investigated.3. Area 3a, in the depths of the postcentral bank, which is cytoarchitectonically transitional between areas 3 and 4, is the receiving area for afferent impulses from muscle.4. Evoked potential waves and unitary discharges began 4 msec, and the majority of units discharged between 5 and 10 msec, after the afferent volley reached the dorsal root entry zone.5. Similar responses were elicited by a brief pull (70 mu in 1 msec) or brief vibration (50 mu at 250-400 Hz) applied to the tendons of m. extensor digitorum communis.6. No potential waves were evoked in area 4, even in the depths adjacent to area 3a, by muscle afferent volleys.

1. One hundred and fifty efferent axons innervating m. extensor digitorum communis (EDC) were isolated in filaments of C7 and C8 ventral roots of baboons. Conduction velocities were measured antidromically by stimulating the muscle nerve and recording from the filaments, and fell into two groups: a fast (49-84 m/sec) and a slow (22-41m/sec), presumably fusimotor group. The threshold for these latter axons exceeded the strength needed to elicit the maximal motor twitch.2. Stimulation of ventral root filaments containing slow axons produced no contractile tension in EDC.3. Stimulation of ventral root filaments containing fast-group axons elicited all-or-nothing twitches of motor units of EDC. The twitch tensions of 66.3% of the units were < 2.0 g wt.; only 8.7% were > 5.0 g wt. Tetanus-twitch ratios were 1.4-4.7 in a sample of 14 units. Contraction times were between 15 and 35 msec in 97% of the units. There was no correlation between contractile properties and axonal conduction velocity.4. Afferent volleys from the stimulated EDC nerve were recorded from C6 or C7 dorsal roots. The threshold was below the threshold for a just-detectable motor twitch in ten out of eleven baboons. Conduction velocity of the earliest component of the muscle afferent volley was 67-83 m/sec.5. The conduction velocities of twenty-eight spindle afferents, identified by their responses to linear stretches of EDC and by their unloading by maximal twitches, were all < 70 m/sec. Higher dynamic sensitivity tended to be associated with higher conduction velocity.

1. Intracellular records were obtained from motoneurones innervating muscles of the baboon's forearm and hand. Monosynaptic excitatory postsynaptic potentials (EPSPs) were elicited by stimulation of motor cortex (CM EPSPs) and peripheral nerves (Ia EPSPs).2. CM EPSPs were larger on average in motoneurones innervating intrinsic hand muscles and extensor digitorum communis (EDC) than in neurones of other forearm muscles.3. Among motoneurones of the median nerve, the CM EPSP tended to be larger for cells with more rapidly conducting axons than for those with more slowly conducting axons. Among motoneurones of EDC the opposite tendency was found.4. The afferent fibres responsible for the Ia EPSP nearly always had a lower stimulus threshold than that of motor axons in the same nerve. Some observations were made concerning the distribution of heteronymous Ia EPSPs.5. Among motoneurones of a given nerve, those with large Ia EPSPs tended to receive larger CM EPSPs than did cells in which the Ia EPSP was small.6. The results are discussed in relation to problems concerning the pyramidal control of hand and finger movement.

1. Peripheral nerves of the baboon's forelimb were stimulated at different sites, and the latencies of antidromic action potentials were measured in intracellular records from forelimb motoneurones.2. The conduction velocity of single motor axons was slower in the brachial plexus than in the nerves of the arm and forearm. This proximal slowing of conduction velocity was more marked for rapidly conducting axons than for the more slowly conducting ones.3. Gross recordings from dorsal and ventral roots showed that the conduction velocity was slower in the brachial plexus than in the arm for fast afferent as well as efferent nerve fibres.4. The proximal slowing of conduction velocity was shown to be due neither to errors of measurement nor to proximo-distal differences of temperature.

1. The corticospinal connexions that are responsible for the firing of fusimotor impulses at short latency in response to brief, high-frequency stimulation of the baboon's motor cortex have been investigated by micro-electrode recording from antidromically identified fusimotor neurones of the forearm and hand.2. Of nineteen fusimotor neurones investigated by intracellular recording, six showed EPSPs at monosynaptic latency.3. In extracellular records, the latency of firing of an early fusimotor impulse was always too long to be explained by monosynaptic excitation by the corticospinal D volley, but could be explained by monosynaptic excitation from an I volley.4. Four of the nineteen intracellularly recorded fusimotor neurones showed short-latency (?disynaptic) IPSPs in response to brief high frequency cortical bursts.