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1.
Comput Biol Med ; 151(Pt A): 106024, 2022 12.
Article in English | MEDLINE | ID: mdl-36327887

ABSTRACT

BACKGROUND: COVID-19 infected millions of people and increased mortality worldwide. Patients with suspected COVID-19 utilised emergency medical services (EMS) and attended emergency departments, resulting in increased pressures and waiting times. Rapid and accurate decision-making is required to identify patients at high-risk of clinical deterioration following COVID-19 infection, whilst also avoiding unnecessary hospital admissions. Our study aimed to develop artificial intelligence models to predict adverse outcomes in suspected COVID-19 patients attended by EMS clinicians. METHOD: Linked ambulance service data were obtained for 7,549 adult patients with suspected COVID-19 infection attended by EMS clinicians in the Yorkshire and Humber region (England) from 18-03-2020 to 29-06-2020. We used support vector machines (SVM), extreme gradient boosting, artificial neural network (ANN) models, ensemble learning methods and logistic regression to predict the primary outcome (death or need for organ support within 30 days). Models were compared with two baselines: the decision made by EMS clinicians to convey patients to hospital, and the PRIEST clinical severity score. RESULTS: Of the 7,549 patients attended by EMS clinicians, 1,330 (17.6%) experienced the primary outcome. Machine Learning methods showed slight improvements in sensitivity over baseline results. Further improvements were obtained using stacking ensemble methods, the best geometric mean (GM) results were obtained using SVM and ANN as base learners when maximising sensitivity and specificity. CONCLUSIONS: These methods could potentially reduce the numbers of patients conveyed to hospital without a concomitant increase in adverse outcomes. Further work is required to test the models externally and develop an automated system for use in clinical settings.


Subject(s)
COVID-19 , Deep Learning , Adult , Humans , Artificial Intelligence , COVID-19/diagnosis , Machine Learning , Hospitals
2.
Med Vet Entomol ; 34(3): 327-343, 2020 09.
Article in English | MEDLINE | ID: mdl-32357384

ABSTRACT

Relative abundance, species composition and temporal activity of Culicoides midges were studied for a period of 2 years (2012-2014) using suction ultra violet light traps at two sites located in the agriculture heartland of West Bengal, India. Surveillance in close proximity to cattle recorded predominance of five species with C oxystoma and C. peregrinus as the most dominant species followed by C. fulvus, C. innoxius and C. anophelis. The temporal activity of midges was investigated for seven consecutive nights at one site in August-September, 2012 and the predominant species was Culicoides oxystoma followed by Culicoides peregrinus. All of the species exhibited crepuscular activity with their flight activity increasing from dusk to dawn. Engorged adults constituted dominant age group in collections. Studies on population ecology of the adults midges are of considerable importance predicting for the epidemicity of midge-borne diseases in cattle.


Subject(s)
Biodiversity , Ceratopogonidae/physiology , Age Distribution , Animals , Bluetongue/transmission , Body Size , Cattle , Cattle Diseases/transmission , Female , India , Insect Vectors , Male , Movement , Population Dynamics , Seasons
3.
Med Vet Entomol ; 34(4): 411-419, 2020 12.
Article in English | MEDLINE | ID: mdl-32426858

ABSTRACT

The preferential attraction of adult Culicoides (Diptera: Ceratopogonidae) to specific wavelengths was studied in West Bengal, India. A total of 280 collections were made with suction light traps fitted with various colours of light emitting diodes (LEDs) placed at cattle sheds during June, August and November in 2017. In addition, the numbers that have been collected in the evening and morning were compared. Locally manufactured suction light traps fitted with ultra violet (UV), blue, green, yellow, pink, red and white LEDs were compared. UV light attracted the highest number of midges followed by blue and then green LED. Culicoides peregrinus Kieffer and Culicoides oxystoma Kieffer were the most abundant followed by Culicoides fulvus Sen and Das Gupta, Culicoides innoxius Sen and Das Gupta, Culicoides anophelis Edwards and Culicoides huffi Causey. The species composition remained similar across the wavelengths. Although significant variations in midge population have been observed across the months, no significant difference in dusk and dawn abundance was noticed. The females showed a mixed population with less parous individuals.


Subject(s)
Ceratopogonidae , Insect Control/methods , Animals , Female , India , Insect Control/instrumentation , Light , Ultraviolet Rays
4.
Animals (Basel) ; 10(3)2020 Feb 28.
Article in English | MEDLINE | ID: mdl-32121116

ABSTRACT

Protocols for assessing the welfare of dairy cows in large scale intensive dairy systems in the developed world have been used extensively. Little attention has been paid to the use of similar welfare assessment protocols for small dairy enterprises in developing countries. We modified part of the standard assessment protocol and used it to assess aspects of the welfare of dairy cows in a field survey of 70 small farms in the Sirajgonj district of Bangladesh. Welfare indicators selected were mainly those of health and economic importance, such as lameness, lesions on the body and limbs, cleanliness levels, milk yield, and body condition. The study included physical examination of 700 cows and use of a structured questionnaire to collect data on health and management practices and farmers' perspectives about animal welfare. Mean milk yield, averaged across farms, was 10.3 L/d (range 6.3-14.2) and body condition assessment indicated that cows were, on average, thin. Hygiene management was often poor, with soiling of body parts with faeces. The prevalence of lameness, at 4.3%, was less than has commonly been observed in larger, more intensive dairy farms, but body injuries were commonly detected at the carpal and hock joints (56 and 51% of cows, respectively). This suggests that floors and/or bedding to lie on were inadequate. Many farmers did not follow routine vaccination and deworming schedules (63% and 31%, respectively) and farmers were not generally aware of the concept of animal welfare. The study demonstrates some similar welfare issues to those that have been commonly identified in large, intensive units, but also some differences, in particular a failure to provide good floors, bedding, and basic health care.

5.
Environ Monit Assess ; 191(7): 440, 2019 Jun 15.
Article in English | MEDLINE | ID: mdl-31203473

ABSTRACT

Production of quality jute fibre primarily depends on the retting process of jute. However, the quality of retting water is of great concern because of the scarcity of available water bodies for retting. A study conducted on physico-chemical and microbiological changes in retting water (pre- and post-retting) from four intensively jute-growing districts namely Nadia, North 24 Parganas, Hooghly and South Dinajpur of West Bengal, India, during jute retting. The post-retting water samples recorded lower pH (6.22 to 7.08) and higher EC (electrical conductivity) (0.509 to 0.850 ds/m) compared with pre-retting water samples (pH 6.63 to 7.44; EC 0.197 to 0.330 ds/m) collected from all the four districts under study. The biological oxygen demand (BOD) and chemical oxygen demand (COD) increased several folds in the post-retting water samples indicating very high microbial growth and activities and depleted oxygen level compared with pre-retting water. The Ca + Mg (calcium + magnesium) content in pre-retting water was high (24.15 to 36.60 ppm) which raised further (61.30 to 103.67 ppm) in post-retting water, while the bicarbonate content also increased and ranged between 2.72 and 6.81 me/l in post-retting water compared with its status in pre-retting water (1.30 to 3.15 me/l). The post-retting water was found to be a rich source of nutrients like nitrogen (N), phosphorus (P), iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu) which increased substantially because of jute retting as compared with their status in pre-retting water. The population of pectinolytic, xylanolytic, cellulolytic and ligninolytic bacterial cfu (colony forming unit) increased by 1.5 times in post-retting water as compared with pre-retting water, because these specific bacterial population were involved in the degradation of pectin, xylan, cellulose and lignin during retting of jute. Thus, post-retting water can be judiciously used as a potent source of primary, secondary and micronutrients for succeeding crops besides having higher BOD and COD as a result of higher microbial growth related to jute retting.


Subject(s)
Bacteria/metabolism , Corchorus/metabolism , Lignin/metabolism , Water/metabolism , Bicarbonates/analysis , Calcium/analysis , Cellulose , Environmental Monitoring , India , Magnesium/analysis , Oxygen/metabolism
6.
Epidemiol Infect ; 147: e15, 2018 Sep 28.
Article in English | MEDLINE | ID: mdl-30264685

ABSTRACT

Giardiasis is one of the most important non-viral causes of human diarrhoea. Yet, little is known about the epidemiology of giardiasis in the context of developed countries such as Australia and there is a limited information about local sources of exposure to inform prevention strategies in New South Wales. This study aimed to (1) describe the epidemiology of giardiasis and (2) identify potential modifiable risk factors associated with giardiasis that are unique to south-western Sydney, Australia. A 1:2 matched case-control study of 190 confirmed giardiasis cases notified to the South-Western Local Health District Public Health Unit from January to December 2016 was employed to investigate the risk factors for giardiasis. Two groups of controls were selected to increase response rate; Pertussis cases and neighbourhood (NBH) controls. A matched analysis was carried out for both control groups separately. Variables with a significant odds ratio (OR) in the univariate analysis were placed into a multivariable regression for each matched group, respectively. In the regression model with the NBH controls, age and sex were controlled as potential confounders. Identified risk factors included being under 5 years of age (aOR = 7.08; 95% confidence intervals (CI) 1.02-49.36), having a household member diagnosed with a gastrointestinal illness (aOR = 15.89; 95% CI 1.53-164.60) and having contact with farm animals, domestic animals or wildlife (aOR = 3.03; 95% CI 1.08-8.54). Cases that travelled overseas were at increased risk of infection (aOR = 19.89; 95% CI 2.00-197.37) when compared with Pertussis cases. This study provides an update on the epidemiology and associated risk factors of a neglected tropical disease, which can inform enhanced surveillance and prevention strategies in the developed metropolitan areas.

7.
Phys Chem Chem Phys ; 19(39): 26862-26869, 2017 Oct 11.
Article in English | MEDLINE | ID: mdl-28952613

ABSTRACT

The effects of solvents on the conformation of hemin and their implications on the dynamics of the complex have been studied using the time-resolved optical Kerr effect (OKE) with 35 fs laser pulses (at a central wavelength of 800 nm). The OKE enabled estimation to be made of the third-order nonlinear electronic susceptibility (χ(3)) of hemin solutions: it was found to be significantly smaller than that in hemin thin films. The real and imaginary components of χ(3) were negative in both the solvents, suggesting that one-photon as well as two-photon absorption processes contribute to the nonlinear electronic susceptibility of hemin. Our study of the ultrafast heme dynamics not only unveils the instantaneous electronic response related to electronic susceptibility but also brings to the fore a novel libration process that has hitherto remained undetected. The hindered rotation in the femtosecond domain that may be responsible for this libration process possibly stems from π-π hemin oligomers formed in aqueous solution. The present results provide new insights into the conformational dynamics in the self-assembly of heme oligomers that may also be significant in certain pathogenic conditions where free heme is formed in biological systems.

8.
Phys Rev Lett ; 119(1): 017401, 2017 Jul 07.
Article in English | MEDLINE | ID: mdl-28731770

ABSTRACT

We have utilized a plethora of transient and steady state optical and magneto-optical spectroscopies in a broad spectral range (0.25-2.5 eV) for elucidating the primary and long-lived photoexcitations in a low band-gap π-conjugated donor-acceptor (DA) copolymer used for efficient photovoltaic solar cells. We show that both singlet excitons (SE) and intrachain triplet-triplet (TT) pairs are photogenerated in the DA-copolymer chains. From the picosecond transient magnetic field response of these species we conclude that the SE and TT spin states are coupled. The TT decomposition into two intrachain geminate triplet excitons maintains spin coherence and thus their spin entanglement lasts into the microsecond time domain.

9.
Intern Med J ; 46(8): 955-63, 2016 Aug.
Article in English | MEDLINE | ID: mdl-26602489

ABSTRACT

BACKGROUND: Opioid prescribing/dispensing data can inform policy surrounding regulation by informing trends and types of opioid prescribed and geographic variations. In Australia so far only partial data on dispensing have been published, and data for states/territories remain unknown. AIM: Using a range of measures, this study examines 20-year (1992-2011) trends in prescription opioid analgesics in Australia - both nationally and for individual jurisdictions. METHODS: Dispensing data were obtained from the Drug Utilisation Sub-Committee and the Pharmaceutical Benefits Scheme (PBS) websites. Trends in numbers of prescriptions and daily defined dose (DDD)/1000 people/day were examined over time and across states/territories. Seasonal variations in PBS/Repatriation Pharmaceutical Benefits Scheme (RPBS) items for nationwide dispensing were adjusted using a centred moving smoothing technique. RESULTS: In two decades, 165.32 million prescriptions for opioids were dispensed, with codeine and its derivatives the most prescribed formulation (50.1%) followed by tramadol (13.5%) and oxycodone derivatives (12.7%). In terms of DDD/1000 people/day, dispensing increased from 5.38 in 1992 to 14.46 in 2011. There are significant increasing trends for total, PBS/RPBS and under co-payment prescriptions (priced below patient co-payment). The DDD/1000 people/day for items dispensed through PBS/RPBS was highest in Tasmania. CONCLUSION: Prescription opioid dispensing increased substantially over the study period. With an ageing population, this trend is likely to continue in future. A growing concern about harms associated with opioid use warrants balanced control measures so that harms could be minimised without reducing effective pain treatment. Research examining utilisation in small geographic areas may help design spatially tailored interventions. A real-time drug-monitoring programme may reduce undue prescribing and dispensing.


Subject(s)
Analgesics, Opioid/administration & dosage , Drug Prescriptions/statistics & numerical data , Drug Utilization/trends , Pain/drug therapy , Pain/epidemiology , Australia/epidemiology , Humans , Pain Management , Practice Patterns, Physicians'
10.
Indian J Nephrol ; 24(5): 308-11, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25249721

ABSTRACT

Lupus cystitis is a rare complication of systemic lupus erythematosus (SLE) and occurs in association with gastrointestinal symptoms. This rare disorder has been reported mainly from Japan. We report a 20 year old female who diagnosed as having SLE associated with paralytic ileus and chronic interstitial cystitis. Treatment with intravenous methylprednisolone, cyclophosphamide pulse therapy followed by oral prednisolone and azathioprine led to amelioration of manifestations. Later she developed lupus nephritis which was treated with mycophenolate mofetil.

12.
J Phys Condens Matter ; 25(38): 385603, 2013 Sep 25.
Article in English | MEDLINE | ID: mdl-23995074

ABSTRACT

A frustrated, effective ½-filled band Hubbard-Heisenberg model has been proposed for describing the strongly dimerized charge-transfer solid families κ-(ET)2X and Z[Pd(dmit)2]2. In addition to showing unconventional superconductivity, these materials also exhibit antiferromagnetism, candidate spin-liquid phases, and, in the case of Z=EtMe3P, a spin-gapped phase that has sometimes been referred to as a valence bond solid. We show that neither superconductivity nor the valence bond order phase occurs within the Hubbard-Heisenberg model. We suggest that a description based on »-filling, that is reached when the carrier concentration per molecule instead of per dimer is considered, thus may be appropriate.

13.
Ann Trop Med Parasitol ; 105(3): 197-208, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21801498

ABSTRACT

India is among the countries that are worse affected by human malaria, one of the major vector-borne diseases that continue to affect vast populations across the world. In a recent household survey in the Terai region of eastern India, the factors that might explain the occurrence and clustering of human malaria and the consequent healthcare-seeking behaviour of the human population were explored. The topography and geo-climatic conditions in Terai appear to intensify the risks of malaria but some socio-economic attributes, such as engagement in agricultural occupations, poor economic status and congested household environments, were also identified as significant risk factors for the disease. In the study area, public health facilities predominate as sources of medical care for malaria, although, at least in the early stages of treatment seeking, informal providers and pharmacies are also often involved. Unfortunately, despite the high frequency of malarial outbreaks, the local public health facilities were found to be ill-equipped to tackle and contain the spread of malaria. Preventive public-health measures, health education on malaria and malaria-awareness exercises were found to be scarce and irregular. The reliance on a reactive strategy of offering curative care to the affected led to overcrowding in healthcare facilities and shortages of medicines and diagnostic procedures. Along with a more efficient and reliable emergency system to deal with major outbreaks of malaria, more effective convergent interventions, by the local government and other stakeholders, should be developed to help prevent the disease.


Subject(s)
Malaria/epidemiology , Patient Acceptance of Health Care/statistics & numerical data , Public Health , Adolescent , Adult , Age Distribution , Aged , Antimalarials/supply & distribution , Antimalarials/therapeutic use , Attitude to Health , Child , Child, Preschool , Disease Outbreaks , Health Behavior , Health Facilities/statistics & numerical data , Humans , India/epidemiology , Infant , Infant, Newborn , Malaria/diagnosis , Malaria/drug therapy , Middle Aged , Prevalence , Risk Factors , Rural Health/statistics & numerical data , Seasons , Socioeconomic Factors , Young Adult
14.
Phys Rev Lett ; 106(21): 216401, 2011 May 27.
Article in English | MEDLINE | ID: mdl-21699322

ABSTRACT

A natural explanation for the carrier concentration-dependent electronic behavior in the layered cobaltates emerges within correlated-electron Hamiltonians with finite on-site and significant nearest neighbor hole-hole Coulomb repulsions. The nearest neighbor repulsion decreases hole double occupancy below hole density 1/3, but increases the same at higher hole densities. Our conclusion is valid for both single-band and three-band extended Hubbard Hamiltonians, and sheds light on concentration dependent e'(g) hole occupancy within the latter.

15.
J Phys Condens Matter ; 22(27): 272201, 2010 Jul 14.
Article in English | MEDLINE | ID: mdl-21399248

ABSTRACT

The competition between antiferromagnetic and spin-singlet ground states within quantum spin models and the ½-filled band Hubbard model has received intense scrutiny. Here we demonstrate a frustration-induced transition from Néel antiferromagnetism to a spin-singlet state in the interacting »-filled band on an anisotropic triangular lattice. While the antiferromagnetic state has equal charge densities, 0.5, on all sites, the spin-singlet state is a paired-electron crystal, with pairs of charge-rich sites separated by pairs of charge-poor sites. The paired-electron crystal provides a natural description of the spin-gapped state proximate to superconductivity in many organic charge transfer solids. Pressure-induced superconductivity in these correlated-electron systems is likely a result of a transition from the »-filled band valence bond solid to a valence bond liquid.

16.
Indoor Air ; 19(1): 3-13, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19191923

ABSTRACT

UNLABELLED: Quick information on airborne infectious disease transmission in airliner cabins is essential to reduce the risk of infection of passengers and crew members. This investigation proposed a one-dimensional analytical model that can predict the longitudinal transmission of airborne contaminants or disease viruses inside an airliner cabin. The model considered both diffusive and convective transport of contaminants in the longitudinal direction of the cabin but assumed complete mixing of contaminants in the cabin cross-section. The effect of recirculation of the cabin air and efficiency of the high-efficiency particulate air (HEPA) filters is also considered in the model. The analytical solution for the one-dimensional contaminant transport model is obtained by using the principle of superposition and the method of separation of variables. The analytical solutions agree well with the computational fluid dynamics (CFD) results. The coupling of a CFD model with the one-dimensional analytical model could capture the impact of local airflow on contaminant transport. This analytical model has been used for analyzing contaminant transport in a 30-row all-economy-class airliner cabin with minimal computing effort. PRACTICAL IMPLICATIONS: The paper presents a new one-dimensional analytical model that can provide quick information on global airborne contaminant transmissions in airliner cabins for effective response plans. The model can be used to study the effects of air exchange rates, recirculation, efficiency of the high-efficiency particulate air (HEPA) filters and longitudinal airflow on airborne contaminant transport in airliner cabins with minimal computing effort.


Subject(s)
Air Movements , Air Pollution, Indoor , Aircraft , Models, Theoretical , Disease Transmission, Infectious
17.
Phys Rev Lett ; 101(16): 166403, 2008 Oct 17.
Article in English | MEDLINE | ID: mdl-18999691

ABSTRACT

We report exact calculations of magnetic and superconducting pair-pair correlations for the half-filled band Hubbard model on an anisotropic triangular lattice. Our results for the magnetic phases are similar to those obtained with other techniques. The superconducting pair-pair correlations at distances beyond nearest neighbor decrease monotonically with increasing Hubbard interaction U for all anisotropy, indicating the absence of frustration-driven superconductivity within the model.

19.
Nano Lett ; 7(8): 2351-5, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17628114

ABSTRACT

We measured the optical properties of mixed valent vanadium oxide nanoscrolls and their metal-exchanged derivatives in order to investigate the charge dynamics in these compounds. In contrast to the prediction of a metallic state for the metal-exchanged derivatives within a rigid band model, we find that the injected charges in Mn2+-exchanged vanadium oxide nanoscrolls are pinned. A low-energy electronic excitation associated with the pinned carriers appears in the far infrared and persists at low temperature, suggesting that the nanoscrolls are weak metals in their bulk form, dominated by inhomogeneous charge disproportionation and Madelung energy effects.


Subject(s)
Crystallization/methods , Manganese/chemistry , Nanostructures/chemistry , Nanostructures/ultrastructure , Nanotechnology/methods , Vanadium Compounds/chemistry , Electron Transport , Energy Transfer , Macromolecular Substances/chemistry , Materials Testing , Metals/chemistry , Molecular Conformation , Particle Size , Surface Properties
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