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Following publication of the original article [1], the authors flagged that the article had gone to publishing with errors in Tables 1-3.

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BACKGROUND: Lung cancer is the leading cause of cancer mortality in Australia. Guidelines suggest that patients with suspected lung cancer on thoracic imaging be referred for urgent specialist review. However, the term "suspected" is broad and includes the common finding of lung nodules, which often require periodic surveillance rather than urgent invasive investigation. The British Thoracic Society recommends that a lung nodule with a PanCan risk > 10% be considered for invasive investigation. This study aimed to assess which factors influence general practitioners (GPs) to request urgent review for a lung nodule and if these factors concur with PanCan risk prediction model variables. METHODS: A discrete choice experiment was developed that produced 32 individual case vignettes. Each vignette contained eight variables, four of which form the parsimonious PanCan risk prediction model. Two additional vignettes were created that addressed haemoptysis with a normal chest computed tomography (CT) scan and isolated mediastinal lymphadenopathy. The survey was distributed to 4160 randomly selected Australian GPs and they were asked if the patients in the vignettes required urgent (less than two weeks) specialist review. Multivariate logistic regression identified factors associated with request for urgent review. RESULTS: Completed surveys were received from 3.7% of participants, providing 152 surveys (1216 case vignettes) for analysis. The factors associated with request for urgent review were nodule spiculation (adj-OR 5.57, 95% CI 3.88-7.99, p < 0.0001), larger nodule size, presentation with haemoptysis (adj-OR 4.79, 95% CI 3.05-7.52, p < 0.0001) or weight loss (adj-OR 4.87, 95% CI 3.13-7.59, p < 0.0001), recommendation for urgent review by the reporting radiologist (adj-OR 4.68, 95% CI 2.86-7.65, p < 0.0001) and female GP gender (adj-OR 1.87, 95% CI 1.36-2.56, p 0.0001). In low risk lung nodules (PanCan risk < 10%), there was significant variability in perceived sense of urgency. Most GPs (83%) felt that a patient with haemoptysis and a normal chest CT scan did not require urgent specialist review but that a patient with isolated mediastinal lymphadenopathy did (75%). CONCLUSION: Future lung cancer investigation pathways may benefit from the addition of a risk prediction model to reduce variations in referral behavior for low risk lung nodules.

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Scorpions are abundant in arid areas, where their population biomass may exceed that of vertebrates. Since scorpions are predators of small arthropods and feed infrequently across multi-year lifespans, a parsimonious explanation for their observed, anomalously high biomass may be a depressed metabolic rate (MR). We tested the hypothesis that scorpion MR is significantly depressed compared with that of other arthropods, and we also measured the temperature-dependence of the MR of scorpions to quantify the interaction between large seasonal variations in desert temperatures and MR and, thus, long-term metabolic expenditure. Scorpion MR increased markedly with temperature (mean Q(10)=2.97) with considerable inter-individual variation. At 25 degrees C, the MRs of scorpions from two genera were less than 24 % of those of typical terrestrial arthropods (spiders, mites, solpugids and insects) of the same mass. It is likely, therefore, that the low MR of scorpions contributes to their high biomass in arid areas. The combination of high biomass and high production efficiency associated with low MR may also favor a density-dependent "transgenerational energy storage" strategy, whereby juveniles are harvested by cannibalistic adults that may be closely related to their juvenile prey.

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ABSTRACT Recent studies on elder abuse suggest that the pathology or impairment of the abuser may be a stronger predictor of elder abuse than characteristics of the victim. To examine the relationship between elder abuse, abuser pathology, and the criminal justice system, the New York City Department for the Aging (DFTA) undertook a survey of older victims of reported domestic abuse seeking assistance from the DFTA Elderly Crime Victims Resource Center. Preliminary findings from the survey indicate that impaired abusers were significantly younger than unimpaired abusers and more likely to live with their elderly victims, to be unemployed, and to have a history of involvement with the criminal justice system.

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This article traces the emergence of forensic social work from the Progressive Era and the founding of the first juvenile court in 1899 to present day policies and practices with victims of violent crimes and with juvenile and adult offenders. Although social workers have been providing outreach to at-risk youths, gang members, offenders, and crime victims for a century, the term "forensic social work" has not previously been widely used. A unifying definition of forensic social work is provided. This article examines the most significant federal initiatives that have provided funding for forensic social workers to reach out to at-risk youths, offenders, and crime victims. It emphasizes the role of forensic social workers in different settings: police departments, juvenile courts, probation departments, adult corrections, and domestic violence and victim assistance programs. This article also includes a discussion of the unique contribution of forensic social workers in advocating for the social service needs of crime victims as well as of offenders.

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In most animals the central pathways of olfactory systems are associated with glomerular neuropil and lack topographic mapping of sensory inputs. Among arthropods, the insect and crustacean olfactory (antennal) pathways are typical examples. Two orders of chelicerate arthropods, the scorpions and solpugids (Cl. Arachnida), present striking exceptions to this generalization. The major chemosensory organs of scorpions are the pectines, two ventral appendages that contact the substrate intermittently as the animal searches for food or mates. In solpugids chemosensory input is from the antennalized pedipalps and first leg pairs, and from ten fan-shaped malleoli extending ventrally to the substrate from the 4th leg pair. The pectinal and malleolar sensory systems have highly ordered arrangement of 10(5) to 10(6) primary chemoreceptors, with one (pectines) forming a two-dimensional array and the other (malleoli) assembled in a linear array. The spatial frequencies of these chemoreceptive inputs exceed 100/mm and 1000/mm, respectively, indicating a capacity for resolving structure of chemical deposits on substrates. Using several histological and axonal tracing techniques, the organization of pectinal and malleolar central projections has been resolved. The pectinal projection terminates posteriorly in the cephalothoracic mass and shows a high degree of topographic precision, perhaps to the level of individual receptors in the sensory field. This chemosensory 'map' is imposed on laminar cytoarchitecture posteriorly in the brain but merges anteriorly into glomerular substructures. The sensory projection from the malleoli shows less topographic order with fewer and larger glomeruli reminiscent of the insect olfactory system. These comparisons between arthropod taxa suggest that olfactory projections are, to varying degrees, typically glomerular but may evolve topographic and laminar organization when the stimulus field is of fixed form.

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By behavioral and anatomical criteria, the pectinal sensory appendages of scorpions appear to be chemoreceptive organs specialized for detection of substances on substrates. These comb-like, midventral appendages contain tens of thousands of minute (< 5 microns), truncated setae, called pegs, arranged in dense, two-dimensional arrays on the ventral surface. In this study we used extracellular recording techniques to examine spontaneous and stimulated activity of sensory neurons within individual pegs. Chronic recordings lasting several days showed long-term fluctuations in spontaneous activity of sensory units in single peg sensilla, with peak activity coinciding with the animal's normal period of foraging. Several units were identified by the stereotypical waveforms of action potentials they elicit. Near-range olfactory stimulation of peg sensilla by volatile alcohols, aldehydes, ketones, esters, and carboxylic acids produced dose-dependent patterns of neural response. Contact stimulation with these chemicals, or water, or mechanical deflection of the peg tip also evoked activity in identifiable units. The peg sensilla appear to be broadly sensitive to odorants and tastants, suggesting they function similarly to the antennae of mandibulate arthropods.

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The pectines of scorpions are ventral bilateral appendages supporting 10(4)-10(5) chemosensory sensilla called pegs. Each peg contains 10-18 sensory neurons, some of which show ultrastructural evidence of axo-axonic synapses with other sensory neurons in the same sensillum. In extracellular recordings from single-peg sensilla, individual sensory units can be distinguished by impulse waveform and firing frequency. Cross-correlation analysis of impulse activity showed that at least two of these units, types 'A1' and 'A2', are inhibited during the 100-ms period immediately following activity of a third unit, type 'B'. This interaction between sensory units in a single sensillum also occurs in surgically isolated pectines, indicating that it does not involve efferent feedback from the central nervous system. Other sensillar neurons appear to have excitatory interactions. Thus, in scorpion pectine, chemosensory information undergoes some form of processing within individual sensilla prior to its relay to the CNS, making this an unusually accessible preparation for study of first-order chemosensory processing events.

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1. The heart of the nudibranch mollusc Archidoris montereyensis is uniquely responsive to regulation by identifiable cardiac motor neurons. The neurotransmitters mediating the strong excitatory and inhibitory actions of the neurons are unknown. 2. In this study we developed an infused, in vitro preparation of the Archidoris heart to determine which of several cardioactive transmitters described in mollusks could affect changes in the rate, amplitude, or tonus of cardiac contractions. Several neurotransmitters we tested increased the rate and amplitude of heart contractions, including serotonin (threshold < 10 nM), dopamine (100 nM), and the neuropeptides R15 alpha 2 (3 nM), small cardioactive peptide B (10 nM), and FMRFamide (20 microM). Myomodulin also excited the heart (0.8 microM) and potentiated the cardioexcitatory action of serotonin at subthreshold concentrations. 3. Only acetylcholine (10 nM) inhibited the heart, decreasing the rate, amplitude, and tonus of contraction. Glycine and the peptides substance P and R15 alpha 1 had no effect on the heart. 4. Antisera against the active neurotransmitters labeled central neurons and nerves innervating the heart in a pattern consistent with their putative cardioregulatory functions. 5. Thus, despite the simplicity of the cardiac motor circuit in Archidoris, contractile activity of the heart appears to be regulated by several neurotransmitters, each with subtly different modes and thresholds of action.

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We describe a group of neurons with egg-laying bioactivity in the cerebral ganglia of an opisthobranch mollusc, the nudibranch Archidoris montereyensis. These cells, the intercerebral white cells (IWCs), share morphological, biochemical, and electrophysiological characteristics with the egg-laying neuroendocrine cells of two other molluscs, Aplysia californica (bag cells) and Lymnaea stagnalis (caudodorsal cells). The IWCs, comprising two superficial clusters of about 100 neurons each, were located immediately posterior to the intercerebral commissure in the cerebral ganglia. The somata of these cells were small (< 20 microns) and possessed varicose, bifurcating unipolar processes that collectively formed a loop within the commissure and bilateral extensions into the cerebral ganglia. The IWC clusters and commissural processes were enveloped by a large ganglionic vascular sinus, forming a potential neurohemal release site. Homogenates of whole cerebral ganglia or isolated IWC clusters induced egg-laying behavior within hours of injection into the hemocoel of quiescent animals. The IWCs were immunoreactive for alpha bag-cell peptide, one of the neuropeptide transmitters encoded by the egg-laying hormone gene of Aplysia. Electrophysiologically, the IWCs were silent neurons with large resting potentials and appeared to be highly refractory to electrical stimulation. The similarities of the IWCs to the egg-laying neuroendocrine cells in Aplysia and Lymnaea suggest that they are members of a homologous group of neurons controlling egg-laying behavior in gastropod molluscs.

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This review concerns the organization and function of arterial vasculature in Aplysia californica, especially the vasomotor reflexes that support circulatory homeostasis, and fixed patterns of response that may reroute blood flow during changes in behavioral state. The observations presented here raise three hypotheses for further study: 1) Arterial vasculature is functionally organized with precisely structured, independently regulated subdivisions; these are most evident for arterial systems serving digestive and reproductive processes; 2) arterial musculature is inherently responsive to local pressure changes, having both static and dynamic reflexes that promote efficient, evenly-distributed flow of blood; and 3) complex, long-lasting behaviors like egg laying have, as part of their makeup, equally prolonged and stereotypical changes in the pattern of circulation. Taken together, these observations support the view that maintenance and adjustment of blood flow in gastropod molluscs is an unexpectedly complex and highly integrated component of behavior.

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The heart of the nudibranch mollusc Archidoris montereyensis is regulated by a small number of powerful effector neurons located in the right pleural and visceral ganglia. Two identifiable neurons in the pleural ganglion, a heart excitor (PlHE) and a heart inhibitor (PlHI), are especially important regulators of cardiac function in that low levels of spontaneous activity in either cell significantly alters the amplitude and rate of heart contractions. These neurons have extensive dendritic arbors within the right pleural ganglion and branching axonal processes within the visceral ganglion. The visceral ganglion also contains a heart excitor neuron (VHE) and at least two heart inhibitor neurons (VHI cells), but their influence on cardiac activity is weaker than that of the pleural ganglion cells. All of these heart effector cells appear to be motor neurons with axons that terminate predominantly in the atrio-ventricular valve region of the heart via the pericardial nerve. The simplicity and strength of these neuronal connections to the heart of Archidoris make this a favorable preparation for studies of cardiac regulation.

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Mesophyll chloroplasts from sodium-deficient compared to normal plants of the C(4) species Kochia childsii and Amaranthus tricolor were found to have significantly less stacking in their grana. On the other hand, no marked difference of thylakoid arrangement between bundle sheath chloroplasts from sodium-deficient and normal plants of A. tricolor were observed.

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The abdominal ganglion of the mollusk Aplysia californica receives most of its blood supply through a small caudal artery that branches off the anterior aorta near its junction with the heart. Injection of an ink/gelatin mixture into the caudal artery revealed a consistent pattern of arterial branching within the ganglion and a general proximity of larger vessels to identified neurons controlling circulation in this animal. This morphological arrangement was particularly evident for the heart excitor interneuron, cell L10, which lies next to the caudal artery near its entry into the ganglion. In electrophysiological experiments, L10 was excited when blood flow or oxygen tension within the ganglion was reduced. This effect was expressed as a gradual increase in impulse frequency of L10 and conversion from tonic to bursting mode of spike discharge. L10 follower cells in the RB and LD neuron clusters were affected synaptically by the changes in L10 activity, while other follower cells (L3 and RD neurons) responded independently of L10's synaptic influence. The neurosecretory white cells (R3 to R14) that innervate the major arteries and pericardial tissues were also excited when ganglionic circulation was interrupted. In innervated preparations of the heart and respiratory organs, decreased circulation through the abdominal ganglion stimulated a transient increase in the rate and amplitude of respiratory (gill) pumping and pericardial contractions and caused a sustained increase in activity of the heart. Both responses increase cardiac output and both appear to involve a direct influence of ganglionic circulation on interneurons controlling the gill and heart. These results indicate that the cell-specific patterns of excitation and inhibition caused by fluctuations in ganglionic circulation may be important factors for maintaining circulatory homeostasis in this animal.

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Respiratory pumping of the gill and siphon of Aplysia californica is a fixed-action pattern coordinated by a defined set of interneurons and motor neurons. In semi-intact preparations of the gill and siphon innervated by the abdominal ganglion, respiratory pumping is facilitated for a prolonged period following activation of the peptidergic bag cell neurons. The induced changes in contractile behavior of the gill and siphon correlate with cell-specific actions of the bag cells on motor neurons regulating these organs. Our results suggest that peptidergic neurons can alter the expression of a fixed pattern of behavior by modulating the excitability of motor neurons controlling the behavior.

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The relationship between long-term electrical activity and protein phosphorylation was investigated in single, identifiable neurons in the abdominal ganglion of Aplysia californica by the intracellular injection of radiolabeled ATP followed by sodium dodecyl sulfate (SDS) gel electrophoresis. Natural and pharmacological treatments that alter the impulse activity of neurons L6 and R15 for prolonged periods did not appear to affect the phosphorylation of most of the 15 major phosphoproteins examined in these cells. Long-term excitation of L6 induced by the phosphodiesterase inhibitor IBMX correlated with phosphorylation of a 29,000-dalton protein. Long-term inhibition of L6 induced by afterdischarge of peptidergic bag-cell neurons appeared to cause dephosphorylation of a 29,000-dalton protein. Burst augmentation of R15 induced by bag-cell afterdischarge did not cause detectable changes in the phosphorylation of the major proteins we examined. These data are consistent with other studies of neural and nonneural tissues which have found a correlation between activity and the level of phosphorylation of a 29,000-dalton protein.

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The bag cell neurons of the marine mollusk Aplysia are a putative multitransmitter system which utilizes two or more neuropeptides that are enzymatically cleaved from a common precursor protein. It has been proposed that one of the neuropeptides, egg-laying hormone (ELH), acts nonsynaptically as a neurotransmitter in the abdominal ganglion by diffusing long distances to target neurons compared to conventional transmitters acting at synapses. To test this idea further, we investigated the physiological properties of neurotransmission mediated by ELH. We found that ELH acts directly to duplicate two types of responses produced by a burst discharge of the bag cells: prolonged excitation of LB and LC cells, and the previously described effect of ELH, burst augmentation of cell R15. Analysis of perfusate collected after electrical stimulation of the bag cells showed that the peptide is released in sufficient quantity to diffuse long distances within the ganglion without being completely inactivated. To mimic the way the peptide is thought to be released physiologically, ELH was arterially perfused into the ganglion. The response normally produced by bag cell activity was duplicated by 0.5 to 1.0 microM concentrations of ELH and showed no rapid desensitization. ELH had no effect on cells that are unaffected by bag cell activity and no effect on cells that are inhibited (LUQ cells) or transiently excited (cells L1 and R1) by bag cell activity. Acidic peptide, another peptide encoded on the ELH precursor protein, was found to be synthesized and released by the bag cells, but it had no effect on the cells we tested. We conclude that the combined properties of ELH neurotransmission resemble the properties of transmission at autonomic nerve endings on cardiac and smooth muscle rather than those of conventional synaptic transmission. ELH released from bag cells is dispersed throughout the interstitial and vascular spaces of the ganglion to produce responses in the cells that have receptors for the peptide. The results also suggest that ELH mediates only a subset of the responses induced by bag cell activity; they are consistent with data indicating that the other responses are mediated by other bag cell peptides derived from the same precursor protein as ELH.

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The peptide-secreting bag cell neurons of Aplysia californica activate a long-lasting, complex behavior called egg laying. During egg laying some organ systems (reproductive) are more active than others (digestive) suggesting that blood flow to these tissues may change in accordance with their activities during egg laying. To examine this possibility we used a semi-intact preparation of the three major arteries innervated by the abdominal ganglion. We found that electrically stimulated bursts of bag cell activity triggered a long-lasting (greater than 1 h) increase in contractile activity in two arteries, the anterior and gastroesophageal, but did not affect contractions of the third (abdominal) artery. The arterial responses were not affected either in form or duration by denervation of the arteries, suggesting that the increase in contractile activity was mediated by hormonal actions of bag cell transmitters on vasoconstrictor muscles. In intact animals this differential action on the arterial system may cause a long-term decrease in blood flow to relatively inactive tissues (digestive and locomotory organs) while increasing circulation to tissues involved in egg production (ovotestis and oviduct).

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1. The bag cells are a group of neuroendocrine cells located in the abdominal ganglion of Aplysia. Accumulated evidence suggests they synthesize and release egg-laying hormone (ELH), a peptide that induces egg laying. In this and the following paper (37) we describe five types of prolonged neural responses in cells of the isolated abdominal ganglion that are produced by stimulated bag cell activity. 2. Prolonged, 5- to 40-min bursts of spike activity were triggered in the normally silent bag cells by local stimulation of one of the bag cell clusters with brief, 0.6- to 2-strains of pulses. This local stimulation minimized the possible effects of the stimulus on other ganglion cells and initiated bag cell activity similar to what has been recorded in intact animals at the initiation of egg laying. 3. Following onset of triggered bag cell activity there is an increase in the amplitude of the bursting pacemaker potential in cell R15 that results in augmented bursting activity in this autoactive cell for up to 3 h. The increase begins in less than 1 min and reaches a maximim after 8--20 min. In two other bursting pacemaker cells, L3 and L6, there is a second type of response, slow inhibition, consisting of a smoothly graded hyperpolarization that begins in 5--14 s, reaches a peak value of 10--20 mV after 30 s, and results in a decrease in the spontaneous spike activity of these cells for 3 h or longer. Both types of responses are contingent on the occurrence of bag cell activity, they depend on prolonged bag cell activity for their normal expression, and they occur in the absence of the fast interactions characteristic of conventional synapses. 4. The results reveal at the level of intracellular recordings prolonged actions of peptide-secreting neuroendocrine cells on the central nervous system. The role of ELH as a putative mediator of one or more of these actions is discussed.

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1. A survey of identified cells of the abdominal ganglion of Aplysia was undertaken to determine the extent of bag cell influence in the ganglion. Bursts of bag cell spike activity lasting 5--40 min were elicited by brief, 0.6- to 2 s local stimulation while recording simultaneously from bag cells and other ganglion cells with intracellular electrodes. 2. Slow inhibition occurs in giant cell R2, neurosecretory cells R3-R14, and ink-gland motoneurons, L14A, B, C. The cells remain hyperpolarized for from 15 to 60 min. 3. Transient excitation occurs in mechanoreceptor cells L1 and R1. The cells are strongly depolarized by a slow excitatory potential that lasts for about 10 min and produces spike activity for 3--7 min. 4. Prolonged excitation occurs in some cells of the LB and LC identified cell clusters. The cells are depolarized and spike activity is increased for 3 h or more. 5. A biphasic response occasionally occurs in the command interneuron L10. Inhibition of this cell lasts 10--15 min and is followed by excitation for several hours. Excitation is accompanied by facilitation of synaptic potentials for 40--60 min in cells innervated by L10; the facilitation apparently results from the increase in L10 firing rate. 6. The results indicate that the bag cells have multiple types of actions and affect large numbers of ganglion neurons. All effects have the slowly graded onsets and prolonged durations to be expected of hormonally mediated interactions. 7. Previous studies have indicated that in intact animals the bag cell burst discharge initates a stereotyped egg-laying behavioral pattern that persists for several hours (3, 27). The present data support the hypothesis that certain elements of egg-laying behavior and homeostasis are regulated by a direct action of the bag cells on the central nervous system.

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