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1.
BMJ Mil Health ; 168(1): 38-42, 2022 Feb.
Article in English | MEDLINE | ID: mdl-31324707

ABSTRACT

INTRODUCTION: The aim of this study was to compare and contrast the profiles of military veterans seeking formal support for post-traumatic stress disorder (PTSD) in national treatment programmes in Australia and the UK to better understand the needs of this vulnerable population. METHODS: Data were extracted from 1926 participants in these treatment programmes. This consisted of 1230 from the UK who had accessed support between 2014 and early 2019, and 696 from Australia who had accessed support between 2014 and 2018. Comparison was made between a number of sociodemographic characteristics (age, sex and educational achievements), military factors (branch of military, time since leaving the military and whether participants were early service leavers or not) and health outcomes (PTSD, anger, alcohol misuse, anxiety and depression). RESULTS: Small differences were observed, with those in the UK cohort appearing to be younger, having lower educational achievement, being more likely to be ex-Army, having longer periods of enlistment in the military and taking longer to seek help. Further, minor differences were reported in health outcomes, with those in the UK cohort reporting more severe symptoms of PTSD, anger, anxiety and depression. CONCLUSIONS: Overall, the observed differences between the cohorts were modest, suggesting that treatment-seeking veterans from the Australian and UK cohorts reported similar presentations. This provides evidence to support the establishment of international cohorts of treatment-seeking veterans to improve knowledge within this field.


Subject(s)
Military Personnel , Stress Disorders, Post-Traumatic , Veterans , Australia/epidemiology , Humans , Stress Disorders, Post-Traumatic/epidemiology , Stress Disorders, Post-Traumatic/therapy , United Kingdom
2.
Nat Commun ; 12(1): 6209, 2021 Oct 27.
Article in English | MEDLINE | ID: mdl-34707115

ABSTRACT

Stimulated Brillouin scattering experiments in the ionospheric plasma using a single electromagnetic pump wave have previously been observed to generate an electromagnetic sideband wave, emitted by the plasma, together with an ion- acoustic wave. Here we report results of a controlled, pump and probe beat-wave driven Brillouin scattering experiment, in which an ion-acoustic wave generated by the beating of electromagnetic pump and probe waves, results in electromagnetic sideband waves that are recorded on the ground. The experiment used the EISCAT facility in northern Norway, which has several high power electromagnetic wave transmitters and receivers in the radio frequency range. An electromagnetic pump consisting of large amplitude radio waves with ordinary (O) or extraordinary (X) mode polarization was injected into the overhead ionosphere, along with a less powerful probe wave, and radio sideband emissions observed on the ground clearly show stimulated Brillouin emissions at frequencies agreeing with, and changing with, the pump and probe frequencies. The experiment was simulated using a numerical full-scale model which clearly supports the interpretation of the experimental results. Such controlled beat-wave experiments demonstrate a way of remotely investigating the ionospheric plasma parameters.

3.
Neuroradiol J ; 31(5): 509-512, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30089411

ABSTRACT

Introduction Magnetic resonance imaging (MRI) is most sensitive and specific for characterizing venous malformations (VMs). VMs typically demonstrate central enhancement on delayed-contrast imaging. Fluid-fluid levels (FFLs) are uncommon in VMs and common in lymphatic malformations (LMs). Technology has advanced since the initial description of these findings. Rates of detection of these MRI findings in VMs may have changed as MRI technology and techniques have evolved. Methods and methods A prospectively maintained database from a multidisciplinary vascular anomalies clinic was reviewed to identify patients with final diagnosis of VM or LM. Patients with reviewable contrast-enhanced MRIs were selected, reviewing the oldest MRI studies in the database against the newest MRI studies to identify equal numbers of patients from the temporal extremes. Imaging was reviewed to assess for presence of FFLs. Enhancement was quantified by measuring signal in the same location of the lesion both on pre- and postcontrast sequences Results Forty patients were identified for analysis. Twenty studies with sufficient archived imaging for review were performed between 1995 and 2006; 20 such studies were performed between 2011 and 2012. The new imaging cohort had higher rates of FFL visualization ( p = 0.001). Correlation was found between time to imaging following contrast and degree of enhancement ( p < 0.001). Inverse correlation was found between scan date and time to contrast ( p = 0.001) and scan date and enhancement ( p = 0.021). Conclusion FFLs should no longer be considered exclusionary for the diagnosis of VMs. Timing following contrast administration should be maximized to increase degree of enhancement to confirm the diagnosis of VMs.


Subject(s)
Clinical Protocols , Diagnostic Errors/prevention & control , Magnetic Resonance Imaging/methods , Vascular Malformations/diagnostic imaging , Adolescent , Child , Contrast Media , Female , Humans , Male , Prospective Studies , Retrospective Studies , Young Adult
4.
Psychol Med ; 48(1): 95-103, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29140225

ABSTRACT

BACKGROUND: To determine the patterns and predictors of treatment response trajectories for veterans with post-traumatic stress disorder (PTSD). METHODS: Conditional latent growth mixture modelling was used to identify classes and predictors of class membership. In total, 2686 veterans treated for PTSD between 2002 and 2015 across 14 hospitals in Australia completed the PTSD Checklist at intake, discharge, and 3 and 9 months follow-up. Predictor variables included co-morbid mental health problems, relationship functioning, employment and compensation status. RESULTS: Five distinct classes were found: those with the most severe PTSD at intake separated into a relatively large class (32.5%) with small change, and a small class (3%) with a large change. Those with slightly less severe PTSD separated into one class comprising 49.9% of the total sample with large change effects, and a second class comprising 7.9% with extremely large treatment effects. The final class (6.7%) with least severe PTSD at intake also showed a large treatment effect. Of the multiple predictor variables, depression and guilt were the only two found to predict differences in response trajectories. CONCLUSIONS: These findings highlight the importance of assessing guilt and depression prior to treatment for PTSD, and for severe cases with co-morbid guilt and depression, considering an approach to trauma-focused therapy that specifically targets guilt and depression-related cognitions.


Subject(s)
Military Personnel/psychology , Stress Disorders, Post-Traumatic/therapy , Veterans/psychology , Aged , Australia , Depression/psychology , Female , Guilt , Humans , Logistic Models , Male , Middle Aged , Psychiatric Status Rating Scales , Psychotherapy/methods , Severity of Illness Index
5.
Phys Rev Lett ; 119(18): 184801, 2017 Nov 03.
Article in English | MEDLINE | ID: mdl-29219603

ABSTRACT

Experimental results are presented of a broadband, high power, gyrotron traveling wave amplifier (gyro-TWA) operating in the (75-110)-GHz frequency band and based on a helically corrugated interaction region. The second harmonic cyclotron mode of a 55-keV, 1.5-A, axis-encircling electron beam is used to resonantly interact with a traveling TE_{21}-like eigenwave achieving broadband amplification. The gyro-TWA demonstrates a 3-dB gain bandwidth of at least 5.5 GHz in the experimental measurement with 9 GHz predicted for a wideband drive source with a measured unsaturated output power of 3.4 kW and gain of 36-38 dB. The approach may allow a gyro-TWA to operate at 1 THz.

6.
Vaccine ; 35(31): 3889-3896, 2017 07 05.
Article in English | MEDLINE | ID: mdl-28606813

ABSTRACT

In recent years concern has mounted regarding the possibility of a re-emergence of smallpox through biowarfare or bioterrorism. There is also concern over the incidence of human monkeypox in endemic areas and the potential for monkeypox to be accidentally transported to non-endemic areas. In the event of re-emergence of smallpox or emergence of monkeypox, the accepted route of administration for live replicating smallpox vaccine is dermal scarification, which generates a virus-shedding lesion that persists for several days at the vaccination site. The lesion is a potential source of contact transmission of vaccine to individuals who may be contra-indicated for receipt of the live vaccine. In this study, we compare dermal scarification with intramuscular vaccination for replicating smallpox vaccine in a mouse lethal challenge model. Comparisons are made over multiple vaccine and challenge doses and data recorded for lethality, disease severity, and antibody responses. Qualitative and quantitative differences between the two routes are observed, and for the intramuscular route the febrile response is not suppressed after subsequent virulent vaccinia virus challenge. However both routes generate an immune response and protect from severe disease and death. Although dermal scarification is the preferred route of vaccination for the general population, intramuscular vaccination may be an option for people who are not contraindicated for the live vaccine, but who are close contacts of people who are contraindicated for the live vaccine, in an emergency situation.


Subject(s)
Smallpox Vaccine/administration & dosage , Smallpox Vaccine/immunology , Vaccinia virus/immunology , Vaccinia/prevention & control , Administration, Cutaneous , Animals , Disease Models, Animal , Female , Injections, Intramuscular , Mice, Inbred BALB C , Survival Analysis , Treatment Outcome , Vaccines, Attenuated/administration & dosage , Vaccines, Attenuated/immunology
7.
Int J Obstet Anesth ; 29: 18-25, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27720613

ABSTRACT

BACKGROUND: During spinal anesthesia for cesarean delivery phenylephrine is the vasopressor of choice but can cause bradycardia. Norepinephrine has both ß- and α-adrenergic activity suitable for maintaining blood pressure with less bradycardia. We hypothesized that norepinephrine would be superior to phenylephrine, requiring fewer rescue bolus interventions to maintain blood pressure. METHODS: Eighty-five parturients having spinal anesthesia for elective cesarean delivery were randomized to Group P (phenylephrine 0.1µg/kg/min) or Group N (norepinephrine 0.05µg/kg/min) fixed-rate infusions. Rescue bolus interventions of phenylephrine 100µg for hypotension, or ephedrine 5mg for bradycardia with hypotension, were given as required to maintain systolic blood pressure. Maternal hemodynamic variables were measured non-invasively. RESULTS: There was no difference between groups in the proportion of patients who required rescue vasopressor boluses (Group P: 65.8% [n=25] vs. Group N: 48.8% [n=21], P=0.12). The proportion of patients who received ⩾1 bolus of phenylephrine was similar between groups (Group P: 52.6% [n=20] vs. Group N: 46.5% [n=20], P=0.58). However, more patients received ⩾1 bolus of ephedrine in the phenylephrine group (Group P: 23.7% [n=9] vs. Group N: 2.3% [n=1], P<0.01). The incidence of emesis was greater in the phenylephrine group (Group P: 26.3% vs. Group P: 16.3%, P<0.001). Hemodynamic parameters including heart rate, the incidence of bradycardia, blood pressure, cardiac output, cardiac index, stroke volume, and systemic vascular resistance and neonatal outcome were similar between groups (all P<0.05). CONCLUSION: Norepinephrine fixed-rate infusion has efficacy for preventing hypotension and can be considered as an alternative to phenylephrine.


Subject(s)
Anesthesia, Obstetrical/adverse effects , Anesthesia, Spinal/adverse effects , Cesarean Section/adverse effects , Hypotension/prevention & control , Norepinephrine/therapeutic use , Phenylephrine/therapeutic use , Adult , Female , Humans , Infusions, Intravenous , Pregnancy , Treatment Outcome , Vasoconstrictor Agents/therapeutic use
8.
J Perinatol ; 37(2): 150-156, 2017 02.
Article in English | MEDLINE | ID: mdl-27853321

ABSTRACT

OBJECTIVE: The purpose of this study was to explore the multilevel contextual factors that influenced the implementation of the Obstetric Hemorrhage Initiative (OHI) among hospitals in Florida. STUDY DESIGN: A qualitative evaluation was conducted via in-depth interviews with multidisciplinary hospital staff (n=50) across 12 hospitals. Interviews were guided by the Consolidated Framework for Implementation Research and analyzed in Atlas.ti using rigorous qualitative analysis procedures. RESULT: Factors influencing OHI implementation were present across process (leadership engagement; engaging people; planning; reflecting), inner setting (for example, knowledge/beliefs; resources; communication; culture) and outer setting (for example, cosmopolitanism) levels. Moreover, factors interacted across levels and were not mutually exclusive. Leadership and staff buy-in emerged as important components influencing OHI implementation across disciplines. CONCLUSION: Key contextual factors found to influence OHI implementation experiences can be useful in informing future quality improvement interventions given the institutional and provider-level behavioral changes needed to account for evolving the best practices in perinatology.


Subject(s)
Health Knowledge, Attitudes, Practice , Interdisciplinary Communication , Postpartum Hemorrhage/prevention & control , Postpartum Hemorrhage/therapy , Quality Improvement/organization & administration , Female , Florida , Health Plan Implementation/organization & administration , Humans , Interviews as Topic , Perinatology , Personnel, Hospital , Pregnancy , Qualitative Research
9.
J Perioper Pract ; 26(5): 106-13, 2016 May.
Article in English | MEDLINE | ID: mdl-27400488

ABSTRACT

We used electronic medical record (EMR) analysis to determine errors in operating room (OR) time utilisation. Over a two year period EMR data of 44,503 surgical procedures was analysed for OR duration, on-time, first case, and add-on time performance, within 19 surgical specialties. Maximal OR time utilisation at our institution could have saved over 302,620 min or 5,044 hours of OR efficiency over a two year period. Most specialties (78.95%) had inaccurately scheduled procedure times and therefore used the OR more than their scheduled allotment time. Significant differences occurred between the mean scheduled surgical durations (101.38 ± 87.11 min) and actual durations (108.18 ± 102.27 min; P < 0.001). Significant differences also occurred between the mean scheduled add-on durations (111.4 ± 75.5 min) and the actual add-on scheduled durations (118.6 ± 90.1 minutes; P < 0.001). EMR quality improvement analysis can be used to determine scheduling error and bias, in order to improve efficiency and increase OR time utilisation.


Subject(s)
Efficiency, Organizational/standards , Electronic Health Records/organization & administration , Operating Room Nursing/organization & administration , Time Management/organization & administration , Appointments and Schedules , Humans , Perioperative Nursing/organization & administration , West Virginia
10.
Phys Rev Lett ; 115(11): 114802, 2015 Sep 11.
Article in English | MEDLINE | ID: mdl-26406835

ABSTRACT

We demonstrate both theoretically and experimentally the possibility of correlating the phase of a Cherenkov superradiance (SR) pulse to the sharp edge of a current pulse, when spontaneous emission of the electron bunch edge serves as the seed for SR processes. By division of the driving voltage pulse across several parallel channels equipped with independent cathodes we can synchronize several SR sources to arrange a two-dimensional array. In the experiments carried out, coherent summation of radiation from four independent 8-mm wavelength band SR generators with peak power 600 MW results in the interference maximum of the directional diagram with an intensity that is equivalent to radiation from a single source with a power of 10 GW.

11.
Phys Rev Lett ; 113(15): 155002, 2014 Oct 10.
Article in English | MEDLINE | ID: mdl-25375713

ABSTRACT

In this Letter, we present theory and particle-in-cell simulations describing cyclotron radio emission from Earth's auroral region and similar phenomena in other astrophysical environments. In particular, we find that the radiation, generated by a down-going electron horseshoe distribution is due to a backward-wave cyclotron-maser emission process. The backward wave nature of the radiation contributes to upward refraction of the radiation that is also enhanced by a density inhomogeneity. We also show that the radiation is preferentially amplified along the auroral oval rather than transversely. The results are in agreement with recent Cluster observations.

12.
Clin Exp Dermatol ; 39(3): 344-7, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24635076

ABSTRACT

Primary cutaneous amyloidosis describes a group of disorders in which amyloid is deposited in the skin without evidence of systemic involvement. Nodular localized primary cutaneous amyloidosis (NLPCA) is a rare form of these skin-restricted amyloidoses. We present an unusual case of NLPCA in a 51-year-old man, who had clinical and histopathological evidence of subepidermal bullous formation, a unique feature in NLPCA. The possible pathogenesis of this change is discussed.


Subject(s)
Amyloidosis/pathology , Foot Dermatoses/pathology , Skin Diseases, Vesiculobullous/pathology , Humans , Male , Middle Aged , Toes
14.
Int J Obstet Anesth ; 19(4): 373-8, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20696564

ABSTRACT

BACKGROUND: Epidural analgesia is widely used for pain relief during labor. The purpose of this study was to determine if ultrasound measurement of the depth from skin to epidural space before the epidural technique decreases the failure rate of labor analgesia. A secondary objective was to correlate ultrasound depth to the epidural space with actual depth of the needle at placement. METHODS: In this prospective, randomized, non-blinded study, 370 parturients requesting labor epidural analgesia were randomized to receive their epidural technique by first year anesthesia residents with or without prior ultrasound determination of epidural space depth. Outcome variables included the incidence of epidural catheter replacement for failed analgesia and the number of epidural attempts and accidental dural punctures. RESULTS: The ultrasound group had fewer epidural catheter replacements (P<0.02), and epidural placement attempts (P<0.01) compared to the control group. Pearson's correlation coefficients comparing the actual versus ultrasound estimated depth to the epidural space in the longitudinal median and transverse planes were 0.914 and 0.909, respectively. Pearson's correlation coefficient comparing the ultrasound estimated depths to the epidural space in the transverse and longitudinal median planes was 0.940. No significant differences were noted with respect to staff interventions, top-ups, accidental dural punctures, and delivery outcome. CONCLUSIONS: Ultrasound measurement of the epidural space depth before epidural technique placement decreases the rate of epidural catheter replacements for failed labor analgesia, and reduces the number of epidural attempts when performed by first year residents and compared to attempts without ultrasound guidance.


Subject(s)
Anesthesia, Epidural/methods , Anesthesia, Obstetrical/methods , Epidural Space/diagnostic imaging , Adult , Catheters , Double-Blind Method , Female , Humans , Internship and Residency , Linear Models , Medical Errors/statistics & numerical data , Needles , Pregnancy , Prospective Studies , Treatment Failure , Ultrasonography
15.
Phys Rev E Stat Nonlin Soft Matter Phys ; 79(6 Pt 2): 066401, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19658606

ABSTRACT

Models of the elastic, inelastic, and reactive collisions of energetic hydrogen ions, atoms, and molecules are developed for predicting H_{alpha} and H2 near-uv emission, H_{alpha} Doppler profiles, and ion energy distributions for low-pressure, low-current discharges in H2 . The model is applied to spatially uniform electric field E to gas density N ratios of 350 Td< or =E/N< or =45 kTd and 8 x10;{19}< or =Nd< or =10 x10;{21} m;{-2} , where d is the electrode separation and 1 Td=10;{-21} V m;{2} . Mean ion energies at the cathode are 5-1500 eV. Cross sections for H+ , H2+ , H3+ , H, H2 , and excited H(n=3) collisions with H2 and reflection probabilities from electrodes are updated and summarized. Spatial and energy distributions of ions and fast neutrals are calculated using a "multibeam" technique. At the lower E/N and Nd , electron excitation of H_{alpha} dominates near the anode. Excitation of H_{alpha} by fast H atoms near the cathode increases rapidly with pressure through a multistep reaction sequence. At higher E/N , fast H atoms produced at the cathode surface excite much of the H_{alpha} . The model agrees with experimental spatial distributions of H_{alpha} emission and Doppler profiles. Ion energy distributions agree with experiments only for H2+ . Cross sections are derived for excitation of the near-uv continuum of H2 by H atoms.

16.
Phys Rev E Stat Nonlin Soft Matter Phys ; 80(1 Pt 2): 016408, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19658824

ABSTRACT

Spatial distributions of H alpha , H beta , and the near-uv continuum emission from the H2 a ;{3}Sigma g;+ state are measured and compared with a model for low-current electrical discharges in H2 at high E/N and low Nd , where E is the spatially uniform electric field, N is the gas density, and d is the electrode separation. Data are analyzed for 300 Td

17.
Phys Rev E Stat Nonlin Soft Matter Phys ; 80(6 Pt 2): 066401, 2009 Dec.
Article in English | MEDLINE | ID: mdl-20365280

ABSTRACT

Absolute spectral emissivities for Doppler broadened H(alpha) profiles are measured and compared with predictions of energetic hydrogen ion, atom, and molecule behavior in low-current electrical discharges in H2 at very high electric field E to gas density N ratios E/N and low values of Nd , where d is the parallel-plate electrode separation. These observations reflect the energy and angular distributions for the excited atoms and quantitatively test features of multiple-scattering kinetic models in weakly ionized hydrogen in the presence of an electric field that are not tested by the spatial distributions of H(alpha) emission. Absolute spectral intensities agree well with predictions. Asymmetries in Doppler profiles observed parallel to the electric field at 4

19.
Int J Obstet Anesth ; 17(2): 123-9, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18295470

ABSTRACT

BACKGROUND: This prospective, randomized study was performed to see if intermittent labor epidural analgesia was protective against maternal intrapartum fever, compared to continuous epidural infusion. METHODS: Ninety-two healthy, term, nulliparous women in spontaneous labor were assigned to either intermittent (ILEA) or continuous labor epidural analgesia (CLEA), 46 in each group. In both groups, epidural analgesia was established with fentanyl 100 microg, and 8 mL of either 0.125% bupivacaine with fentanyl 0.0002%, or 0.1% ropivacaine with fentanyl 0.0002%. Maintenance in the CLEA group was with the same bupivacaine/fentanyl or ropivacaine/fentanyl solutions at 10-15 mL/h. In the ILEA group, additional boluses of the same solution were given as needed. Maternal tympanic temperature was measured before epidural insertion, 4-hourly during labor and 4 h post partum. Fever was defined as a temperature of > or =38 degrees C. Newborn temperature was noted within 60 min of birth. RESULTS: The incidence of fever in ILEA was significantly lower at four hours (2/42, vs. 10/44 in CLEA, P=0.036). No significant differences were detected at other time periods. Mean maternal temperatures did not differ between groups at any time. There were no differences in neonatal temperature or neonatal sepsis evaluation rate (CLEA vs. ILEA 0/46 vs. 2/43, P=0.45). CONCLUSIONS: Intermittent epidural injections appear to protect against intrapartum fever in the first 4 hours of labor analgesia, compared to continuous infusion. This may be due to intermittent partial recovery of heat loss mechanisms between injections. Neonatal sepsis evaluation rates were similar in the two groups.


Subject(s)
Analgesia, Epidural , Analgesia, Obstetrical , Body Temperature/drug effects , Fever/prevention & control , Obstetric Labor Complications/prevention & control , Adult , Analgesia, Epidural/adverse effects , Analgesia, Epidural/methods , Analgesia, Obstetrical/adverse effects , Analgesia, Obstetrical/methods , Body Temperature/physiology , Female , Fever/etiology , Humans , Incidence , Infant, Newborn , Multivariate Analysis , Obstetric Labor Complications/etiology , Pain Measurement/methods , Postnatal Care/methods , Pregnancy , Prospective Studies , Sepsis/etiology , Time Factors
20.
Phys Rev E Stat Nonlin Soft Matter Phys ; 76(5 Pt 2): 056406, 2007 Nov.
Article in English | MEDLINE | ID: mdl-18233775

ABSTRACT

The first operation of a coaxial free-electron maser (FEM) based on two-dimensional (2D) distributed feedback has been recently observed. Analytical and numerical modeling, as well as measurements, of microwave radiation generated by a FEM with a cavity defined by coaxial structures with a 2D periodic perturbation on the inner surfaces of the outer conductor were carried out. The two-mirror cavity was formed with two 2D periodic structures separated by a central smooth section of coaxial waveguide. The FEM was driven by a large diameter (7 cm), high-current (500 A), annular electron beam with electron energy of 475 keV. Studies of the FEM operation have been conducted. It has been demonstrated that by tuning the amplitude of the undulator or guide magnetic field, modes associated with the different band gaps of the 2D structures were excited. The Ka-band FEM generated 15 MW of radiation with a 6% conversion efficiency, in good agreement with theory.

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