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Background: Previous studies have shown varied results with respect to the diagnostic utility of a positive nerve root sedimentation sign (SedSign) on MRI for symptomatic lumbar stenosis. The objective of this study was to analyze the clinical characteristics of SedSign utilizing a validated classification for low back and leg pain (Saskatchewan Spine Pathway classification; SSPc). Methods: This was a retrospective review of prospectively-collected data in 367 consecutive adult patients presenting to a spine surgeon with back and/or leg pain between January 1, 2012 and May 31, 2018. Inter- and intra-rater reliability for SedSign was 73% and 91%, respectively (3 examiners). Results: SedSign was positive in 111 (30.2%) and negative in 256 (69.8%) of patients. On the univariate analysis, a positive SedSign was correlated with age, male sex, several components of ODI, EQ5D mobility, cross-sectional area (CSA) of stenosis, and SSPc pattern 4 (intermitted leg dominant pain). On multivariate analysis, SedSign was associated with age, male sex, CSA stenosis and ODI sub-score for walking distance. The sensitivity and specificity of SedSign for neurogenic claudication was 50.3 and 82.9, respectively (positive predictive value 65.8%, negative predictive value 71.9%). Conclusions: The SedSign has high specificity for neurogenic claudication, but the sensitivity is poor.
Background: The nerve root sedimentation sign (SedSign) has been correlated with clinically significant lumbar spinal stenosis (LSS), and promoted as a possible prognostic indicator. However, diagnostic methods were not clearly defined in prior reports. In this study, the clinically validated Saskatchewan Spine Pathway enabled diagnosis of neurogenic claudication due to LSS. The objective was to compare the outcome of lumbar laminectomy for neurogenic claudication with respect to SedSign. Methods: This was a retrospective analysis of prospectively-collected data in patients with neurogenic claudication who underwent lumbar laminectomy. Outcome measures included Oswestry Disability Index, Visual Analogue Scale (VAS) for back and leg pain, and EuroQol 5-Dimension questionnaire. Results: Laminectomy was performed in 106 patients, and 60 were SedSign positive. Outcomes did not differ with respect to SedSign for all outcome measures, in non-instrumented and instrumented cohorts. Improvement in walking distance was associated with dural cross-sectional area of stenosis (p=0.02). VAS back and leg improvements were associated with back dominant (p=0.038) and leg dominant (p=0.0036) pain. Conclusions: This is the largest analysis of SedSign with respect to operative outcomes, and the only study with validated criteria for defining neurogenic claudication. Although other radiological and clinical factors are associated with improvements, SedSign did not correlate with laminectomy outcome.
Background: The natural history of small unruptured intracranial aneurysms (UIAs) <7mm is 0 to 1.3% per year. Our centre provides cerebrovascular care for the entire province allowing for long-term follow-up. We studied the safety of observation for aneurysms <7mm. Methods: We performed a retrospective chart review of patients with intracranial aneurysm referred to our centre between July 2008 and April 2015. Aneurysm characteristics and current status (followed, treated, not followed), were collected along with patient factors. Follow-up duration for each aneurysm was used to calculate total follow-up in aneurysm-years. Statistical evaluation consisted of multivariate analysis and logistic regression analysis. Results: 428 patients harbouring 497 aneurysms <7mm were identified. 67 presented with rupture. Of the remaining 430 aneurysms, there was a 9.3% treatment rate. 2 cases of rupture occurred in those patients who were followed, creating a 0.5% rupture rate. 325 aneurysms were followed for 631.3 total cumulative aneurysm-years, an average of 1.9 aneurysm-years. Smoking status and hypertension associated with presence of aneurysm (p≈0.009,0.026, respectively). Conclusions: In our selected patient group there is a low yearly rate of aneurysm rupture, and observation of aneurysms <7mm is safe. Hypertension and smoking were associated with the development of aneurysm. 9.3% of patients were treated, likely leading to a reduced natural history risk.
The Critically Endangered Spoon-billed Sandpiper Calidris pygmaeus is one of the most threatened migratory shorebirds in the world, breeding in Russia and wintering in Asia. The global population is declining rapidly and is projected to be extinct within a few decades without intervention. Here, we present the results of shorebird surveys in previously unrecognised site in Bangladesh along the Meghna Estuary, identified for the first time by using species distribution models. Counts and habitat preference of Spoon-billed Sandpipers and other endangered shorebirds are described here with notes on the global importance of the newly discovered site. The sum of the peak counts for each shorebird species across the two surveys was 25,993 including a minimum of 48 Spoon-billed Sandpipers. The majority of the Spoon-billed Sandpipers were observed during low tide while foraging (66.6%) and logistic regression testing for effects on the presence of foraging Spoon-billed Sandpiper indicate that they mainly preferred to forage on shallow mud. We summarise the threats to Spoon-billed Sandpipers and other birds in the new site that is currently not recognized as a Wetland of International Importance under the Ramsar Convention, although it fulfils several Ramsar Criteria. We also propose conservation and monitoring measures for long-term protection of the Spoon-billed Sandpiper and its habitat.
Salmonellosis is a typical zoonotic disease that occurs frequently in poultry flocks. Many salmonella serovars have been found to be responsible for this disease. In this review besides, poultry as a carrier of Salmonella enterica serovar Typhimurium infection, various infectious routes, pathology, sources of infection are discussed as well as diagnostic measures and preventive strategies that aim at reducing the incidence of salmonellosis at the farm level. Among the different diseases occurring in poultry, those caused by the genus Salmonella is the most common, causing serious losses to the poultry industry in terms of mortality, reduced growth and loss of egg production. The diseases caused by S. enterica serovar Typhimurium have got public health significance, as well as being associated with food poisoning in humans. Salmonellosis in humans is mainly caused by S. typhimurium. The ability of this serovar to infect birds and contaminate eggs makes it a potent infection agent for humans. As S. typhimurium shows foodborne pathogenesis, it is important to comprehend how it can affect eggs and what strategies are needed to enhance control over infection.
Poultry can be exposed to different kinds of immunosuppressive agents that impair health and welfare by destroying innate and acquired immunity leading to diminished genetic potential of poultry for efficient production. Immunosuppression is a condition characterised by humoral and cellular immune dysfunction that leads to increased susceptibility to secondary infections and vaccine failure. Immune dysfunction at the humoral level is largely due to change in soluble factors mediated by complement or chemokines for innate immunity or due to alterations in antibodies or cytokines for adaptive immunity. In contrast, immune dysfunctions at cellular levels include alterations in neutrophils, monocyte/macrophage, and natural killer cells for innate immunity or changes in B or T lymphocytes for adaptive immunity. In poultry, stress-induced immunosuppression is manifested by failure in vaccination, and increased morbidity and mortality of flocks. Immunosuppressive agents can have cytolytic effects on lymphocyte populations leading to atrophied and depleted lymphoid organs. Immunosuppression can be due to infectious agents or non-infectious agents or due to a combination of them. At present, several modern cellular and molecular approaches are being used to determine the status of the immune system during stress and disease. Comprehensive methodologies for the evaluation of immunosuppression by combined non-infectious and infectious aetiologies have not found general application. Currently, investigations are being developed in order to detect genetic expression of immunologic mediators and receptors by microarray technology. It is likely that this new technique will initiate the development of new strategies for the control and prevention of immunosuppression in poultry. A long term immunosuppression preventive approach involves genetic selection for resistance to immunosuppressive diseases. In general, intervention approaches for immunosuppressive diseases largely rely on minimising stress, reducing exposure to infectious agents through biosecurity, and increasing immune responses by vaccination against immunosuppressive agents.
The critical period during which maternal hyperglycemia predisposes offspring to develop reproductive disorders in adult life is not known. The relationship between maternal hyperglycemia at different stages and reproductive functions of male offspring was investigated. A single intraperitoneal injection of alloxan (90 mg/kg body weight) was administered at gestation days (GD) 1, 8 and 15. Animals were subsequently given 10% glucose solution daily as drinking water until parturition. All male pups were sacrificed on the 63rd day of postnatal life. Birth weight, anogenital distance index (AGDi), testes descent day, preputial separation day, sperm profile, serum testosterone, luteinizing hormone and follicle-stimulating hormone levels and the histology of the testis were assessed. Data significance test was based on 95% confidence interval. GD1 pups showed a significant increase in mean birth weight, whereas GD8 pups and GD15 pups had significantly reduced birth weight as compared with control. AGDi was significantly increased in GD8 and GD15 pups. Testes descent and preputial separation in all the experimental groups were significantly earlier. There was a significant reduction in sperm count and viability in GD8 offspring. Sperm motility was reduced in all test groups. Testosterone level was reduced in all test groups. Histology of the testis showed varying degrees of pathologies. It was deduced from this study that maternal hyperglycemia caused alterations in reproductive functions in male offspring of Wistar rats irrespective of the period of gestation involved, although GD8 pups were most severely affected.
In this survey, we review different text mining techniques to discover various textual patterns from the social networking sites. Social network applications create opportunities to establish interaction among people leading to mutual learning and sharing of valuable knowledge, such as chat, comments, and discussion boards. Data in social networking websites is inherently unstructured and fuzzy in nature. In everyday life conversations, people do not care about the spellings and accurate grammatical construction of a sentence that may lead to different types of ambiguities, such as lexical, syntactic, and semantic. Therefore, analyzing and extracting information patterns from such data sets are more complex. Several surveys have been conducted to analyze different methods for the information extraction. Most of the surveys emphasized on the application of different text mining techniques for unstructured data sets reside in the form of text documents, but do not specifically target the data sets in social networking website. This survey attempts to provide a thorough understanding of different text mining techniques as well as the application of these techniques in the social networking websites. This survey investigates the recent advancement in the field of text analysis and covers two basic approaches of text mining, such as classification and clustering that are widely used for the exploration of the unstructured text available on the Web.
In recent practice, we have used tissue transfer (pedicled or free flap) to augment the pharyngeal circumference of the neopharynx following salvage total laryngectomy, even in patients who have sufficient pharyngeal mucosa for primary closure. In this study, the rates of pharyngocutaneous fistula were compared in soft tissue flap reconstructed patients versus patients who underwent primary closure.
A retrospective assessment was carried out of all patients who had undergone a salvage total laryngectomy between 2000 and 2010. The presence or absence of a pharyngocutaneous fistula was compared in those who received reconstruction closure versus those who received primary closure.
The reconstruction closure group (n = 7) had no incidence of pharyngocutaneous fistula, whereas the primary closure group (n = 38) had 10 fistulas, giving pharyngocutaneous fistula rates of 0 per cent versus 26 per cent, respectively.
The findings revealed a lower rate of pharyngocutaneous fistula with tissue transfer compared with primary closure of the neopharynx.
Rabies is a major public health problem in Bangladesh, where most of the population live in rural areas. However, there is little epidemiological information on rabies in rural Bangladesh. This study was conducted in 30 upazilas (subdistricts) covering all six divisions of the country, to determine the levels of rabies and animal bites in Bangladesh. The total population of these upazilas was 6 992 302. A pretested questionnaire was used and data were collected by interviewing the adult members of families. We estimated that in Bangladesh, 166 590 [95% confidence interval (CI) 163 350–170 550] people per year are bitten by an animal. The annual incidence of rabies deaths in Bangladesh was estimated to be 1·40 (95% CI 1·05–1·78)/100 000 population. By extrapolating this, we estimated that 2100 (95% CI 1575–2670) people die annually from rabies in Bangladesh. More than three-quarters of rabies patients died at home. This community-based study provides new information on rabies epidemiology in Bangladesh.
Unprecedented high rates of anthrax outbreaks have been observed recently in cattle and humans in Bangladesh, with 607 human cases in 2010. By enrolling 15 case and 15 control cattle smallholdings in the spatial zone in July–September 2010, we conducted a case-control study, data of which were analysed by matched-pair analysis and multivariable conditional logistic regression. Feeding animals with uprooted and unwashed grass [odds ratio (OR) 41·2, 95% confidence interval (CI) 3·7–458·8, P=0·003], and feeding water hyacinth (Eichhornia crassipes) (OR 22·2, 95% CI 1·2–418·7, P=0·039) were independent risk factors for anthrax in cattle.
In this paper, we consider the question of existence of solutions and their regularity properties for a large class of stochastic evolution equations governed by B-evolutions involving two different Hilbert spaces. This allows dynamic boundary conditions together with noisy boundary data. They cover also stochastic boundary value problems. Our results are illustrated by two practical examples.
Fabrication processes of metal-oxide semiconductor (MOS) capacitors on n-type, Si-face, 6H-SiC were studied. The effects of thermal oxidation conditions at temperatures between 1100 and 1250°C on the electrical properties of MOS capacitors were determined. The wafers were annealed under argon to improve the C-V characteristics. C-V characteristics of AI-SiO2-SiC metal-oxide-semiconductor were measured at high frequency in the dark and under illumination. In the dark inversion does not occur, probably owing to the absence of minority carriers due to the large band gap of 6H-SiC. The accumulation, depletion, and inversion regions were clearly observed when the C-V measurements were made under illumination for both wet and dry thermally grown oxides. The interface trap densities and emission time constants of fast states were determined by ac conductance measurements. From the analysis of data we obtained a total of Fixed charges and the slow interface traps, Nf + NssSlow of 1.5 to 3.3 × 1012 cm-2, fast interface trap densities, NssFast of 0.5 to 1.7 × 1011 cm-2 eV-1 and emission times constant of 0.3 to 1.4 μsec for wet oxidation. For dry oxidation, Nf + N, ssSlow of 3.5 to 11.2 × 10cm-2, NssFast of 0.7 to 1.25 × 1010 cm-2 eV-1 and emission time constants of 0.6 to 2 μsec were obtained.
Engineering of nanoparticles to detect ultraviolet light within a specified range and its feasibility to make a device has been demonstrated. It is shown that the absorption edge of a material can be shifted to significantly lower wavelengths in the UV range by using nanoparticles and that this feature can be incorporated within a device. All experimental work was focused on ZnO. Both commercially obtained ZnO nanoparticles as well as in-house synthesized ZnO nanoparticles were examined. For the in-house developed particles it was shown that varying the diameter of the ZnO nanoparticles could vary the absorption wavelength from 315 to 365 nm. Commercially available nanoparticles did not show this shift due to their relatively larger sizes (diameter ≅ 20 nm) as well as their broad size distributions.
A photocurrent effect of UV light on thin films prepared with nanoparticles has been demonstrated. Not only the optical band-gap value depends on the size of the nanoparticles but also the mobility gap of the material and, as a consequence, the onset of photocurrent.
In February 2007 an outbreak of Nipah virus (NiV) encephalitis in Thakurgaon District of northwest Bangladesh affected seven people, three of whom died. All subsequent cases developed illness 7–14 days after close physical contact with the index case while he was ill. Cases were more likely than controls to have been in the same room (100% vs. 9·5%, OR undefined, P<0·001) and to have touched him (83% vs. 0%, OR undefined, P<0·001). Although the source of infection for the index case was not identified, 50% of Pteropus bats sampled from near the outbreak area 1 month after the outbreak had antibodies to NiV confirming the presence of the virus in the area. The outbreak was spread by person-to-person transmission. Risk of NiV infection in family caregivers highlights the need for infection control practices to limit transmission of potentially infectious body secretions.
Bangladesh faced two epidemic waves of highly pathogenic avian influenza (HPAI) H5N1 in two consecutive years. The peaks of the waves were observed in February–July 2007 and January–April 2008, respectively. We examined the spatial and temporal patterns of the 293 outbreaks in 143 subdistricts in 2007 and 2008. Global clustering assessed by K-function was seen at distances 150–300 km between subdistricts. Significant local clusters were detected by space–time scan statistics. In both waves, significant primary clusters of HPAI outbreaks were identified in the central part of the country dominated by commercial production systems and in the northwestern part primarily in backyard production systems. Secondary clusters varied from the northwestern part in 2007 and the southern part in 2008. The findings are highly relevant for the successful planning and implementation of control, prevention and surveillance strategies by highlighting areas where detailed investigations should be initiated.
Global production and trade in small pelagic fish (SPF) are affected by complex interactions between physical, ecological and economic systems, which give rise to relatively long-term, asynchronous cycles in SPF abundance and distribution. These cycles can have serious impacts on local SPF fisheries' production, but because they tend to be counterbalancing, global production of SPF tends to remain relatively stable. Nevertheless, recent patterns of landings indicate that most SPF are being harvested at or near their maximum yield levels, which in the face of increasing demand is expected to result in rising prices in supply-limited markets. Adding to these concerns are the uncertainties of climate change, which leads us to consider important economic issues related to SPF fisheries production, starting with how the redistribution of SPF resources affects respective rates of resource utilization, particularly when SPF move between independently managed fishing zones. This entails an associated issue, the time preferences for experiencing the range of benefits from SPF resources among nations sharing access to these resources. Because the ecological and economic impacts of climate change will extend well beyond directed SPF fisheries, we consider the economic impact of a climate–SPF regime shift from an ecosystem perspective. Of interest here is the full range of economic benefits SPF resources provide; not only their commercial value, but as prey for commercially valuable predators, and for recreational and non-commercial predators. In this context we examine the socially optimum use of these resources, balancing the benefits from commercially harvesting SPF with those from leaving them in the ocean ecosystem.