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The Canada Health Act requires reasonable access to all medically necessary therapies. No information is available to assess the current access to neuromodulation across Canada. This study quantifies the current rate of deep brain stimulation (DBS) for the entire country of Canada. Analyses were performed to determine whether there were differences in access based on provincial or territorial location, rural or non-rural region, or socioeconomic status.
All implanted DBS devices in Canada over a 2-year epoch (January 2015 to December 2016) were supplied by either Boston Scientific or Medtronic. Investigators received anonymized data from these companies, including patient age and home residence region. The 2016 Statistics Canada census data were used to determine the rate of DBS surgery and whether access was related to provincial location, rural versus non-rural region or socioeconomic status.
A total of 722 patients were studied. The rate of DBS surgery for the entire country was ten per million population per year. Saskatchewan was significantly above (374%) the national average, whereas Quebec (40%) and Newfoundland & Labrador (32%) were significantly below the national average. No patients from the three territories received DBS. There were no significant differences in access from rural versus non-rural areas or in regions within provinces with different socioeconomic status.
This is the first study to quantify all patients receiving DBS within an entire country. The current rate of DBS surgery within Canada is ten cases per million per year. Statistically significant regional differences were discovered and discussed.
Current group-average analysis suggests quantitative but not qualitative cognitive differences between schizophrenia (SZ) and bipolar disorder (BD). There is increasing recognition that cognitive within-group heterogeneity exists in both disorders, but it remains unclear as to whether between-group comparisons of performance in cognitive subgroups emerging from within each of these nosological categories uphold group-average findings. We addressed this by identifying cognitive subgroups in large samples of SZ and BD patients independently, and comparing their cognitive profiles. The utility of a cross-diagnostic clustering approach to understanding cognitive heterogeneity in these patients was also explored.
Hierarchical clustering analyses were conducted using cognitive data from 1541 participants (SZ n = 564, BD n = 402, healthy control n = 575).
Three qualitatively and quantitatively similar clusters emerged within each clinical group: a severely impaired cluster, a mild-moderately impaired cluster and a relatively intact cognitive cluster. A cross-diagnostic clustering solution also resulted in three subgroups and was superior in reducing cognitive heterogeneity compared with disorder clustering independently.
Quantitative SZ–BD cognitive differences commonly seen using group averages did not hold when cognitive heterogeneity was factored into our sample. Members of each corresponding subgroup, irrespective of diagnosis, might be manifesting the outcome of differences in shared cognitive risk factors.
Recent data suggest trait-like neurocognitive impairments in bipolar disorder (BPD), with deficits about 1 s.d. below average, less severe than deficits noted in schizophrenia. The frequency of significant impairment in BPD is approximately 60%, with 40% of patients characterized as cognitively spared. This contrasts with a more homogeneous presentation in schizophrenia. It is not understood why some BPD patients develop deficits while others do not.
A total of 136 patients with BPD completed the MATRICS Consensus Cognitive Battery and data were entered into hierarchical cluster analyses to: (1) determine the optimal number of clusters (subgroups) that fit the sample; and (2) assign subjects to a specific cluster based on individual profiles. We then compared subgroups on several clinical factors and real-world community functioning.
Three distinct neurocognitive subgroups were found: (1) an intact group with performance comparable with healthy controls on all domains but with superior social cognition; (2) a selective impairment group with moderate deficits on processing speed, attention, verbal learning and social cognition and normal functioning in other domains; and (3) a global impairment group with severe deficits across all cognitive domains comparable with deficits in schizophrenia.
These results suggest the presence of multiple cognitive subgroups in BPD with unique profiles and begin to address the relationships between these subgroups, several clinical factors and functional outcome. Next steps will include using these data to help guide future efforts to target these disabling symptoms with treatment.
There is a considerable scarcity of reliable population-based data on the prevalence of preventable ear disorders in developing countries. This study was conducted to determine the prevalence of preventable ear disorders in primary school children (aged 5 to 12 years) in northern India.
A pro forma questionnaire was used to screen 15 718 primary school children in New Delhi for ear disorders. Ear examinations were conducted using otoscopy and impedance audiometry.
Impacted cerumen was prevalent in 7.93 per cent of schoolchildren, 4.79 per cent suffered from chronic otitis media and 3.06 per cent suffered from otitis media with effusion. Acute otitis media was detected in 0.65 per cent and foreign bodies were found in 0.34 per cent of the children.
Preventable ear diseases posed a significant health problem among children at primary school level. Regular screening of children during this stage would ensure that their school lives were not affected by hearing impairments or preventable ear disorders. Information gathered in this study will help in effective treatment prioritisation of ear disorders, planning and resource allocation.
Irradiation of vapor-deposited C60 films with a KeV ion beam (Ar+ or Ga+) transforms the surface layer of C60 into a non-volatile carbon film. During the subsequent annealing at 900°C, the modified C60 layer confines the underlying C60 on the silicon surface, allowing the formation of SiC. With this method, patterned SiC structures on silicon with the high lateral resolution possible with ion beams are fabricated
We demonstrate that picosecond ultrasonics provides detailed information on the structure and properties of patterned arrays of copper fine lines used in silicon chip interconnections. In this method, the sample surface is momentarily heated several °C using a pump laser beam, and the transient change in the optical reflectivity is measured by a probe laser beam. Measurements of the optical reflectivity are made on time scales ranging from picoseconds to nanoseconds, revealing information on electronic, acoustic and thermal properties. We have applied this method to samples consisting of copper line arrays of 0.4 µm linewidth, 0.65 µm pitch and 0.35 µm depth in SiO2 on silicon wafers. For comparison, we examined the picosecond ultrasonic response of 200 nm-thick blanket copper thin films. The patterned Cu lines are found to have long-term oscillations at frequencies of 4.39 and 8.29 GHz with lifetimes at least 10 times longer than the oscillations in the blanket Cu film. A two-dimensional mechanical analysis was developed which uses as input parameters the dimensions and sound velocities of the materials in the sample, and finds the normal mode frequencies and displacements. The main vibrational modes are identified and described for the patterned lines, and the simulations confirm that the lowest frequency modes have very small damping coefficients. Also, the time-dependent signal is shown to reveal details of interface layers and integrity of the copper/liner interface.
Sputtered Mo films with a thickness of 2μm or greater have been previously shown by xray and TEM studies to grow with strong in-plane and out-of-plane textures under dynamic deposition conditions. In this work, the geometric conditions and mechanisms causing preferential grain alignment in the plane of growth for sputtered Mo films, with a nominal thickness of 2μm, were explored. Four different deposition configurations, obtained by varying the parameters such as the deposition angle and the rotation speed of the substrates, were used in order to modify the texture as studied by x-ray and SEM techniques. While a  type out-of-plane texture was observed for all four deposition configurations, a (110) type in-plane texture, and the corresponding grain alignment in the plane of growth, was observed only when the flux of adatoms was hitting the substrates at an oblique angle. The texture characteristics and the microstructure of the Mo films, as analyzed using the pole figure x-ray and SEM techniques, were observed to be very similar for films deposited on three different substrates, namely the Si(100) and Ni3Al(321) single crystals, and laboratory grade glass slides. The in-plane texture development under oblique deposition conditions was proposed to be due to a combination of two mechanisms, namely the preferential resputtering of some of the grains normal to and in the plane of growth caused by the higher energy adatoms in the flux, followed by termination of the preferentially sputtered grains due to geometric shadowing.
Pulsed laser deposited cerium oxide (CeO2) nanoporous thin film on platinum (Pt) coated glass has been used for immobilization of glucose oxidase (GOx) by electrostatic interaction. Atomic force microscopy studies reveal the formation of nanoporous surface morphology of CeO2 thin film. Differential pulse voltammetric and optical measurements show that the GOx/CeO2/Pt bioelectrode is sensitive to the detection of glucose over the concentration upto 300 mg/dl. A low value of enzyme's kinetic parameter (Michaelis-Menten constant∼1.01 mM) indicates enhanced enzyme affinity of GOx to glucose.
The morphologic variations of mixed totally anomalous pulmonary venous connection are many and varied. In this review, we give an account of all cases previously described as mixed totally anomalous pulmonary venous connection, analyzing in detail those cases where an accurate anatomical description was provided. We identified 182 suitable cases, from 54 investigations, and reviewed the clinical presentation, anatomic variations, diagnostic features, and management of the patients described.
Cross-sectional echocardiography, and cardiac catheterization, provided the necessary diagnostic information, and defined the anatomy before surgery in 139 patients. Magnetic resonance imaging and computerized tomographic angiography had been used for further clarification of the pulmonary venous anatomy. An obstructive pattern of drainage, involving one or more pulmonary veins, had been described in over half of the patients. We then grouped the lesions into categories that have a bearing on the appropriate surgical approach, discussing the appropriate repair for each group. For the overall group, the operative mortality remains high, at 22.9%. We submit that an increased appreciation of various types of mixed totally anomalous pulmonary venous connection may well contribute to improved future surgical management.
A patent vertical vein might be desirable in patients with obstructive totally anomalous pulmonary venous connection with pulmonary hypertension, in order to decrease perioperative pulmonary arterial pressure and avoid pulmonary hypertensive crises. A subset of patients with an unligated vertical vein requires interruption of the vein due to the development of significant left-to-right shunt and right heart failure. We describe here a new device, permitting adjustable ligation of the vertical vein, which permits us to avoid multiple reoperations.
Patients and methods
In five patients, aged 2, 4, 3, 4, and 3 months respectively, and undergoing rechannelling of totally anomalous pulmonary venous connection with an unligated vertical vein, were treated with a device permitting adjusted ligation of the vertical vein over the course of postoperative congestive cardiac failure.
There was no early or late death. Postoperatively, all ligatures were tightened gradually over a period of 24 to 96 hours, maintaining stable haemodynamics. At a mean follow-up of 55.40 months, there was no evidence of congestive heart failure in any patient, the clinical risk score varying from zero to 2, and no requirement of anti-failure medications. Computed tomographic angiograms during follow-up revealed absence of flow through the vertical vein, and ruled out distortion of the left upper pulmonary and left brachiocephalic veins.
Use of a percutaneously adjustable device to ligate the vertical vein allows gradual tightening or loosening of the ligature under optimal physiologic conditions, without re-opening the sternum, or having to resort to another thoracotomy once the reactive components of pulmonary hypertension disappear.
The systematics of two Southeast Asian green pitviper species, Trimeresurus hageni and T. sumatranus, are investigated by canonical variate analysis. Preliminary results reveal two morphological forms corresponding to mainly T. hageni in West Malaysia, Thailand and Singapore and T. sumatranus in Borneo. Allopatric populations of both taxa are examined from Sumatra. Geographic variation is present in both species, which are distinguished mainly by head scalation, but also by colour and pattern.
Background and objective: Auditory impairment is among the lesser known complications of spinal analgesia. The aim of the present study was to determine the degree of vestibulocochlear dysfunction in patients undergoing spinal analgesia for lower abdominal surgery.
Methods: Eighty patients who had received spinal analgesia for lower abdominal surgery were studied. Males were undergoing inguinal herniorraphy and the females tubectomy. Audiograms were performed before operation and on the second and seventh postoperative days. Hearing levels were measured from 250 Hz-8 kHz. In Group 1 (n = 40) a 22-gauge, cutting type of spinal needle (Howard Jones) was used. In Group 2 (n = 40) a 25-gauge, non-cutting spinal needle (Whitacre) was used.
Results: Hearing loss ' 10 dB was noticed in three patients in Group 1 and none in Group 2. The mean hearing level was more reduced in Group 1 patients.
Conclusions: Use of cutting type spinal needle is associated with a greater decrease in mean hearing levels compared to the non-cutting type.
Poorly defined cohorts and weak study designs have hampered cross-cultural comparisons of course and outcome in schizophrenia.
To describe long-term outcome in 18 diverse treated incidence and prevalence cohorts. To compare mortality, 15- and 25-year illness trajectory and the predictive strength of selected baseline and short-term course variables.
Historic prospective study. Standardised assessments of course and outcome.
About 75% traced. About 50% of surviving cases had favourable outcomes, but there was marked heterogeneity across geographic centres. In regression models, early (2-year) course patterns were the strongest predictor of 15-year outcome, but recovery varied by location; 16% of early unremitting cases achieved late-phase recovery.
A significant proportion of treated incident cases of schizophrenia achieve favourable long-term outcome. Sociocultural conditions appear to modify long-term course. Early intervention programmes focused on social as well as pharmacological treatments may realise longer-term gains.
This prospective, double-blind, randomized study assessed effect of pre-emptive peritonsillar block in 30 ASA–I children, aged 6–12 years, of both sexes, scheduled for tonsillectomy. Patients were divided into three groups: those in group I received a sham block, whereas peritonsillar blocks with bupivacaine 0.25% were given to the children before tonsillectomy (group II) or immediately after surgery had been completed (group III). Constant pain, pain on swallowing, blood glucose, serum epinephrine and norepinephrine concentrations were measured immediately after surgery and 4 h after operation. Patients in group I experienced more pain (P < 0.05) than those in groups II and III, both in the immediate postoperative period and over the next 4 h. Patients in groups II and III experienced similar pain (P > 0.05). The pain experienced when water was swallowed was similar to that of the constant pain. The rise of serum norepinephrine concentration in group II was significantly less (P < 0.05) compared to groups I and III. We found both pre-emptive and postoperative block to be equally effective in treating postoperative pain, with pre-emptive block being more effective in preventing the rise in norepinephrine concentration.
In this work the effect of grain size and magnetic switching volume on media noise due to intergranular coupling for CoCrTaPt/Cr thin film media deposited at substrate temperature of 160 and 260°C are investigated. The film deposited at substrate temperature of 260°C showed weaker intergranular interaction and lower media noise compared to the film deposited at 160°C. The magnetic switching volume (V*) is an important consideration for thermal stability and media noise in high density recording media. The magnetic switching volume V* for the film deposited at 160 and 260°C was calculated to be 3.7 x 10-18 and 3.2 x 10-18 cm3 respectively. The magnetic switching volume is correlated to the average Co-alloy grain size, media noise and the interactions between the grains.
The imposition of swirl on co-axial jets exhausting into confined space, akin to a combustor model, has far reaching effects on their mixing and flow development. In the present paper, the influence of swirl on both the jets has been determined in terms of velocity and pressure distributions in the confined space. It has been shown that swirl in the central jet leads to faster mixing whereas higher swirl in the annular jet improves both mixing and development.