Identification of suitable zones and sites for rainwater harvesting using GIS and multicriteria decision analysis.

Identifying suitable zones for surface water storage and groundwater recharge is needed to enhance irrigation water availability. This study was undertaken to map rainwater harvesting (RWH) potential zones using geospatial tools and analytic hierarchy process (AHP). The suitable locations for RWH were also mapped using the Boolean logic concept. The surface runoff is a vital factor to demarcate the appropriate zones for RWH. The curve number approach was used to estimate the surface runoff potential. The runoff coefficient (RC) map was generated based on rainfall and surface runoff depth. Weights have been allocated to selected themes of RC, drainage density, and slope. The themes were integrated using geographic information system (GIS) and AHP to demarcate the suitable zones for RWH. The derived RWH potential map was categorized into zones like "very good," "good," "moderate," "poor," and "very poor" with an aerial extent of 14.3%, 24.7%, 28.3%, 20.2%, and 12.6%, respectively. The area suitable for farm ponds was found to be about 9% (408 km2), 13% (329 km2), and 4% (244 km2) in Mirzapur, Chandauli, and Sonbhadra districts, respectively. Furthermore, 22, 15, and 21 locations were found suitable for check dams in Mirzapur, Chandauli, and Sonbhadra districts, respectively. At a large scale, effective planning of water management strategies based on multicriteria decision analysis and GIS offers increased availability of surface and groundwater resources and may help for enhancing the agricultural land use options. The higher resolution maps may be further utilized to plan RWH strategies at village level.

The relationship between diabetes and depressive symptoms in men with or at risk of HIV infection.

OBJECTIVES: The aim of the study was to compare the prevalence of comorbid diabetes and depressive symptoms in men living with HIV (MLWH) with that in men without HIV infection and to determine associations between glycaemic control and depressive symptoms. METHODS: Participants included 920 MLWH and 840 men without HIV infection from the Multicenter AIDS Cohort Study (MACS) with available data regarding glycaemic status [categorized as normal for fasting blood glucose (FBG) < 100 mg/dL, prediabetes for FBG 100-125 mg/dL, and diabetes, defined by self-report, diabetes medication use or FBG ≥ 126 mg/dL on at least two consecutive visits, with diabetes classified as controlled if Hemoglobin A1c (HbA1C) < 7.5% and uncontrolled if HbA1C ≥ 7.5%]. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression (CES-D) score, with CES-D ≥ 16 scores classified as elevated depressive symptoms. A modified Poisson regression model with robust variance was used and adjusted for covariates including HIV serostatus. RESULTS: Compared to men without HIV infection, MLWH had a higher mean CES-D score, but a similar prevalence of diabetes (11.3% versus 12.8%, respectively; P = 0.33). The concomitant prevalence of diabetes and elevated depressive symptoms did not differ by HIV serostatus (P = 0.215). In an adjusted analysis, men with uncontrolled diabetes had a greater prevalence of depressive symptoms compared to men with normoglycaemia (prevalence ratio = 1.43; 95% confidence interval 1.11, 1.84). The association between glycaemic status and depressive symptoms did not differ by HIV serostatus (P = 0.22 for interaction). CONCLUSIONS: Both controlled and uncontrolled diabetes were independently associated with a greater prevalence of depressive symptoms, regardless of HIV serostatus. These results highlight the importance of identifying depression in people with diabetes.

Potent anti-mycobacterial and immunomodulatory activity of some bioactive molecules of Indian ethnomedicinal plants that have the potential to enter in TB management.

Tuberculosis (TB) is one of the deadliest infectious diseases of human civilization. Approximately one-third of global population is latently infected with the TB pathogen Mycobacterium tuberculosis (M.tb). The discovery of anti-TB antibiotics leads to decline in death rate of TB. However, the evolution of antibiotic-resistant M.tb-strain and the resurgence of different immune-compromised diseases re-escalated the death rate of TB. WHO has already cautioned about the chances of pandemic situation in TB endemic countries until the discovery of new anti-tubercular drugs, that is, the need of the hour. Analysing the pathogenesis of TB, it was found that M.tb evades the host by altering the balance of immune response and affects either by killing the cells or by creating inflammation. In the pre-antibiotic era, traditional medicines were only therapeutic measures for different infectious diseases including tuberculosis. The ancient literatures of India or ample Indian traditional knowledge and ethnomedicinal practices are evidence for the treatment of TB using different indigenous plants. However, in the light of modern scientific approach, anti-TB effects of those plants and their bioactive molecules were not established thoroughly. In this review, focus has been given on five bioactive molecules of different traditionally used Indian ethnomedicinal plants for treatment of TB or TB-like symptom. These compounds are also validated with proper identification and their mode of action with modern scientific approaches. The effectiveness of these molecules for sensitive or drug-resistant TB pathogen in clinical or preclinical studies was also evaluated. Thus, our specific aim is to highlight such scientifically validated bioactive compounds having anti-mycobacterial and immunomodulatory activity for future use as medicine or adjunct-therapeutic molecule for TB management.

Fire safety and emergency evacuation guidelines for intensive care units and operating theatres: for use in the event of fire, flood, power cut, oxygen supply failure, noxious gas, structural collapse or other critical incidents: Guidelines from the Association of Anaesthetists and the Intensive Care Society.

The need to evacuate an ICU or operating theatre complex during a fire or other emergency is a rare event but one potentially fraught with difficulty: Not only is there a risk that patients may come to harm but also that staff may be injured and unable to work. Designing newly-built or refurbished ICUs and operating theatre suites is an opportunity to incorporate mandatory fire safety features and improve the management and outcomes of such emergencies: These include well-marked manual fire call points and oxygen shut off valves (area valve service units); the ability to isolate individual zones; multiple clear exit routes; small bays or side rooms; preference for ground floor ICU location and interconnecting routes with operating theatres; separate clinical and non-clinical areas. ICUs and operating theatre suites should have a bespoke emergency evacuation plan and route map that is readily available. Staff should receive practical fire and evacuation training in their clinical area of work on induction and annually as part of mandatory training, including 'walk-through practice' or simulation training and location of manual fire call points and fire extinguishers, evacuation routes and location and operation of area valve service units. The staff member in charge of each shift should be able to select and operate fire extinguishers and lead an evacuation. Following an emergency evacuation, a network-wide response should be activated, including retrieval and transport of patients to other ICUs if needed. A full investigation should take place and ongoing support and follow-up of staff provided.

Workplace violence against doctors: Characteristics, risk factors, and mitigation strategies.

Workplace violence is a major occupational issue concerning doctors that has a significant impact on their physical and psychological well-being. This ultimately affects the health care services of the country. Patient-led episodes of verbal violence are more prevalent in Asian countries, especially in the emergency department, psychiatric wards, and intensive care units, mostly faced by junior doctors and residents. Some common precursors of violence against doctors are patients and their attendants' dissatisfaction and low impulse control, poor administration, miscommunication, infrastructural issues especially differences in services between private and public hospitals, and negative media portrayal of doctors. The assessment of risk factors, development and implementation of workplace violence programs, and addressing underreporting of violent episodes have been suggested as some successful organizational mitigation strategies. Recommendations on the management of workplace violence include the development of participative, gender-based, culture-based, nondiscriminatory, and systematic strategies to deal with issues related to violence. This article aims to present a comprehensive review of workplace violence against doctors, discussing the prevalence, degree of violence, predictors, impact on physical and psychological health and intervention strategies to devise practical actions against workplace violence.

Characterization and evaluation of lactic acid bacteria from indigenous raw milk for potential probiotic properties.

Raw milk contains wide microbial diversity, composed mainly of lactic acid bacteria (LAB), which are used as probiotics in both human and animal husbandry. We isolated, characterized, and evaluated LAB from indigenous Bangladeshi raw milk to assess probiotic potential, including antagonistic activity (against Escherichia coli O157: H7, Enterococcus faecalis, Salmonella Typhimurium, Salmonella Enteritidis, and Listeria monocytogenes), survivability in simulated gastric juice, tolerance to phenol and bile salts, adhesion to ileum epithelial cells, auto- and co-aggregation, hydrophobicity, α-glucosidase inhibitory activity, and antibiotic susceptibility tests. The 4 most promising LAB strains showed probiotic potential and were identified as Lactobacillus casei, Lactobacillus plantarum (which produced plantaricin EF), Lactobacillus fermentum, and Lactobacillus paracasei. These strains inhibited all pathogens tested at various degrees, and competitively excluded pathogens with viable counts of 3.0 to 6.0 log cfu/mL. Bacteriocin, organic acids, and low-molecular-weight substances were mainly responsible for antimicrobial activity by the LAB strains. All 4 LAB strains were resistant to oxacillin and 3 were resistant to vancomycin and streptomycin, with multiple antibiotic resistance indices >0.2. After further in vivo evaluation, these LAB strains could be considered probiotic candidates with application in the food industry.

Utilization of LD slag from steel industry for the preparation of MF membrane.

This work is focused on utilizing the solid waste generated from steel industry for the fabrication of porous ceramic membrane from Linz Donawitz (LD) slag. Membranes were fabricated using uniaxial method sintered at three different temperatures like 650 °C, 850 °C and 950 °C. Membranes fabricated with raw LD slag gave a highly basic filtrate. In contrast with this issue, LD slag was modified using acetic acid and CO2 purging to convert calcium oxide which is present in the slag to calcium carbonate. The membranes fabricated from modified LD slag showed a filtrate pH of 8.4 and 8.5. Porosity, pore size distribution, flexural strength, chemical stability was determined and pure water flux experiments were conducted to evaluate the efficiency of the prepared membranes. Considering the raw materials cost, the cost of the fabricated membranes was estimated in the range of 32.55-55.7 USD/m2. This work gives a potential path to develop microfiltration ceramic membrane with, high porosity and great quality in terms of strength and chemical stability. The fabricated membranes were utilized in a hybrid technique (flocculation followed by microfiltration) for the treatment of cold roll mill (CRM) wastewater generated from steel industry. Use of LD slag for the fabrication of ceramic membrane is not only an appealing option towards the commercialization of membrane, yet also great option to reduce the solid waste which is dumped to the environment.

Elemental composition of aquaculture fish from West Bengal, India: nutrition versus food safety.

Aquaculture production continues to grow in West Bengal, where on average people consume 8.2 kg capita-1 of fish each year, and an extensive mosaic of aquaculture ponds has developed along the River Hugli as clay pits are repurposed. The adjacent brickworks and industry (especially tanneries) are a source of environmental pollution, with potential for bioaccumulation of potentially harmful elements (PHEs) in fish farmed in these ponds. Fish from aquaculture present an opportunity to meet food sufficiency in West Bengal; however, an investigation to assess their effectiveness for micronutrient supply balanced against food safety is required. Five ponds close to industrial brick manufacture (urban) and three from rural areas were assessed for the degree of pollution within their pond sediments and waters. Fish were also sampled from each location including a subset from the market in Kolkata to determine the concentrations of PHEs in their fish muscle tissue. Dietary intake and PHE loading were calculated for four fish species to evaluate their nutrient content with respect to recommended daily intakes for adults, e.g. calcium (Ca), potassium (K), magnesium (Mg), iron (Fe), zinc (Zn) and selenium (Se), and to establish whether the provisional maximum tolerable intakes (PMTIs) are exceeded for PHEs, e.g. aluminium (Al), arsenic (As), mercury (Hg), chromium (Cr), tin (Sn), copper (Cu) and lead (Pb). Preliminary results suggest that aquaculture is making an important contribution to nutrition, with fish being a good source of Se. However, in contrast to small wild-caught fish, aquaculture fish in the present study were poor sources of Fe, Ca and Zn. The fish also made substantial contributions (> 10%) to the PMTI of Hg and As. Therefore, there is an urgent need for ongoing monitoring and an expanded sampling programme, as well as research into approaches which might improve the nutritional quality of the farmed fish.

The cerebral angiome: High resolution MicroCT imaging of the whole brain cerebrovasculature in female and male mice.

The cerebrovascular system provides crucial functions that maintain metabolic and homeostatic states of the brain. Despite its integral role of supporting cerebral viability, the topological organization of these networks remains largely uncharacterized. This void in our knowledge surmises entirely from current technological limitations that prevent the capturing of data through the entire depth of the brain. We report high-resolution reconstruction and analysis of the complete vascular network of the entire brain at the capillary level in adult female and male mice using a vascular corrosion cast procedure. Vascular network analysis of the whole brain revealed sex-related differences of vessel hierarchy. In addition, region-specific network analysis demonstrated different patterns of angioarchitecture between brain subregions and sex. Furthermore, our group is the first to provide a three-dimensional analysis of the angioarchitecture and network organization in a single reconstructed tomographic data set that encompasses all hierarchy of vessels in the brain of the adult mouse.

Correction to: Skating on thin ice: pragmatic prescribing for medication refractory schizophrenia.

After publication of the original article [1], the authors have notified us that there was an oversight on acknowledging funding received for the study. They would like to mention that Professor Sukhi Shergill was funded by an ERC Consolidator Award.

Impact of conventional retting of jute (Corchorus spp.) on the environmental quality of water: a case study.

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.

Axion-Driven Cosmic Magnetogenesis during the QCD Crossover.

We propose a mechanism for the generation of a magnetic field in the early Universe during the QCD crossover assuming that dark matter is made of axions. Thermoelectric fields arise at pressure gradients in the primordial plasma due to the difference in charge, energy density, and equation of state between the quark and lepton components. The axion field is coupled to the EM field, so when its spatial gradient is misaligned with the thermoelectric field, an electric current is driven. Because of the finite resistivity of the plasma, an electric field appears that is generally rotational. For a QCD axion mass consistent with observational constraints and a conventional efficiency for turbulent dynamo amplification-driven by the same pressure gradients responsible for the thermoelectric fields-a magnetic field is generated on subhorizon scales. After significant Alfvénic unwinding, it reaches a present-day strength of B∼10^{-13} G on a characteristic scale L_{B}∼20 pc. The resulting combination of BL_{B}^{1/2} is significantly stronger than in any astrophysical scenario, providing a clear test for the cosmological origin of the field through γ-ray observations of distant blazars. The amplitude of the pressure gradients may be inferred from the detection of concomitant gravitational waves, while several experiments are underway to confirm or rule out the existence of axions.

Spectroscopic identification of individual fluorophores using photoluminescence excitation spectra.

The identity of a fluorophore can be ambiguous if other fluorophores or nonspecific fluorescent impurities have overlapping emission spectra. The presence of overlapping spectra makes it difficult to differentiate fluorescent species using discrete detection channels and unmixing of spectra. The unique absorption and emission signatures of fluorophores provide an opportunity for spectroscopic identification. However, absorption spectroscopy may be affected by scattering, whereas fluorescence emission spectroscopy suffers from signal loss by gratings or other dispersive optics. Photoluminescence excitation spectra, where excitation is varied and emission is detected at a fixed wavelength, allows hyperspectral imaging with a single emission filter for high signal-to-background ratio without any moving optics on the emission side. We report a high throughput method for measuring the photoluminescence excitation spectra of individual fluorophores using a tunable supercontinuum laser and prism-type total internal reflection fluorescence microscope. We used the system to measure and sort the photoluminescence excitation spectra of individual Alexa dyes, fluorescent nanodiamonds (FNDs), and fluorescent polystyrene beads. We used a Gaussian mixture model with maximum likelihood estimation to objectively separate the spectra. Finally, we spectroscopically identified different species of fluorescent nanodiamonds with overlapping spectra and characterized the heterogeneity of fluorescent nanodiamonds of varying size.

Spin glass like transition and the exchange bias effect in Co3O4 nanoparticles anchored onto graphene sheets.

We have synthesized Co3O4 nanoparticles having 40 nm average size, which are anchored on reduced graphene oxide. X-ray diffraction, FESEM, TEM and Raman spectroscopy are performed for the characterization. The temperature dependence of field cooled (FC) and zero field cooled (ZFC) magnetization curves exhibits antiferromagnetic (AFM) transition around ∼30 K, as observed for bulk Co3O4. The exchange bias effect is observed below ∼30 K. A significant change in the exchange bias effect is noted around ∼8 K, which is close to a spin-glass-like transition. The spin-glass-like phase has been confirmed by the memory effects observed by different experimental protocols. The possible origin of exchange bias is discussed in the manuscript.

Reduced risk of emergency admission for colorectal cancer associated with the introduction of bowel cancer screening across England: a retrospective national cohort study.

AIM: We wanted to find out if roll-out of the bowel cancer screening programme (BCSP) across England was associated with a reduced risk of emergency hospital admission for people presenting with colorectal cancer (CRC) during this period. METHOD: This is a retrospective cohort study of 27 763 incident cases of CRC over a 1-year period during the roll-out of screening across parts of England. The primary outcome was the number of emergency (unplanned) hospital admissions during the diagnostic pathway. The primary exposure was to those living in an area where the BCSP was active at the time of diagnosis. Patients were categorized into three exposure groups: BCSP not active (reference group), BCSP active < 6 months or BCSP active ≥ 6 months. RESULTS: The risk of emergency admission for CRC in England was associated with increasing age, female gender, comorbidity and social deprivation. After adjusting for these factors in logistic regression, the odds ratio (OR) for emergency admission in patients diagnosed ≥ 6 months after the start-up of local screening was 0.83 (CI 0.76-0.90). The magnitude of risk reduction was greatest for cases of screening age (OR 0.75; CI 0.63-0.90) but this effect was apparent also for cases outside the 60-69-year age group (OR 0.85; CI 0.77-0.94). Living in an area with active BCSP conferred no reduction in risk of emergency admission for people diagnosed with oesophagogastric cancer during the same period. CONCLUSION: The start-up of bowel cancer screening in England was associated with a substantial reduction in the risk of emergency admission for CRC in people of all ages. This suggests that the roll-out of the programme had indirect benefits beyond those related directly to participation in screening.

Quantitative birefringence microscopy with collinearly propagating orthogonally polarized beams.

Full-field evaluation of spatially varying birefringence is realized by allowing two mutually orthogonally polarized collinearly propagating laser beams to be incident on a birefringent sample. This is achieved by use of a modified Sagnac interferometer. A half-wave plate is placed in the exit path of the interferometer to adjust the polarizations of the incident beams as required. Amplitude components of the light emerging from the birefringent object are then selected and/or combined by a polarizer, and intensities for required orientation of the half-wave plate and the analyzer are digitally recorded. It is shown that a maximum of four frames of intensity data is sufficient for complete evaluation of birefringence. The proposed technique is aimed towards birefringence measurements in microscopic biological specimens where the magnitude of retardation lies in the range of 0-π radians. Simulated and experimental results are presented.

Antibacterial activity of polyphenolic fraction of Kombucha against Vibrio cholerae: targeting cell membrane.

The present study was undertaken to determine the mechanism of antibacterial activity of a polyphenolic fraction, composed of mainly catechin and isorhamnetin, previously isolated from Kombucha, a 14-day fermented beverage of sugared black tea, against the enteropathogen Vibrio cholerae N16961. Bacterial growth was found to be seriously impaired by the polyphenolic fraction in a dose-dependent manner. Scanning Electron Microscopy demonstrated morphological alterations in bacterial cells when exposed to the polyphenolic fraction in a concentration-dependent manner. Permeabilization assays confirmed that the fraction disrupted bacterial membrane integrity in both time- and dose-dependent manners, which were proportional to the production of intracellular reactive oxygen species (ROS). Furthermore, each of the polyphenols catechin and isorhamnetin showed the ability to permeate bacterial cell membranes by generating oxidative stress, thereby suggesting their role in the antibacterial potential of Kombucha. Thus, the basic mechanism of antibacterial activity of the Kombucha polyphenolic fraction against V. cholerae involved bacterial membrane permeabilization and morphological changes, which might be due to the generation of intracellular ROS. To the best of our knowledge, this is the first report on the investigation of antibacterial mechanism of Kombucha, which is mostly attributed to its polyphenolic content. SIGNIFICANCE AND IMPACT OF THE STUDY: The emergence of multidrug-resistant Vibrio cholerae strains has hindered an efficient anti-Vibrio therapy. This study has demonstrated the membrane damage-mediated antibacterial mechanism of Kombucha, a popular fermented beverage of sugared tea, which is mostly attributed to its polyphenolic content. This study also implies the exploitation of Kombucha as a potential new source of bioactive polyphenols against V. cholerae.

Mercury levels in human population from a mining district in Western Colombia.

A biomonitoring study was carried out to examine the adverse impacts of total mercury in the blood (HgB), urine (HgU) and human scalp hair (HgH) on the residents of a mining district in Colombia. Representative biological samples (scalp hair, urine and blood) were collected from volunteered participants (n=63) to estimate the exposure levels of THg using a Direct mercury analyzer. The geometric mean of THg concentrations in the hair, urine and blood of males were 15.98µg/g, 23.89µg/L and 11.29µg/L respectively, whereas the females presented values of 8.55µg/g, 5.37µg/L and 8.80µg/L. Chronic urinary Hg (HgU) levels observed in male workers (32.53µg/L) are attributed to their long termed exposures to inorganic and metallic mercury from gold panning activities. On an average, the levels of THg are increasing from blood (10.05µg/L) to hair (12.27µg/g) to urine (14.63µg/L). Significant positive correlation was found between hair and blood urinary levels in both male and female individuals. Thus the present biomonitoring investigation to evaluate the Hg levels and associated health issues would positively form a framework for further developmental plans and policies in building an ecofriendly ecosystem.

Search for Magnetic Monopoles with the MoEDAL Forward Trapping Detector in 13 TeV Proton-Proton Collisions at the LHC.

MoEDAL is designed to identify new physics in the form of long-lived highly ionizing particles produced in high-energy LHC collisions. Its arrays of plastic nuclear-track detectors and aluminium trapping volumes provide two independent passive detection techniques. We present here the results of a first search for magnetic monopole production in 13 TeV proton-proton collisions using the trapping technique, extending a previous publication with 8 TeV data during LHC Run 1. A total of 222 kg of MoEDAL trapping detector samples was exposed in the forward region and analyzed by searching for induced persistent currents after passage through a superconducting magnetometer. Magnetic charges exceeding half the Dirac charge are excluded in all samples and limits are placed for the first time on the production of magnetic monopoles in 13 TeV pp collisions. The search probes mass ranges previously inaccessible to collider experiments for up to five times the Dirac charge.

Identification of factors associated with treatment refractoriness of oral lesions in pemphigus vulgaris.

BACKGROUND: The oral mucosal lesions of patients with pemphigus vulgaris are known to show more treatment refractoriness than skin lesions. OBJECTIVES: To identify which clinical and laboratory parameters may indicate treatment refractoriness of oral lesions in pemphigus vulgaris. METHODS: This was a prospective study of 50 adults with pemphigus vulgaris and oral lesions; patients were given treatment appropriate for overall disease severity. Treatment refractoriness was defined arbitrarily as less than 75% reduction in oral objective Autoimmune Bullous Skin Disorder Intensity Score (ABSIS) after treatment for 6 months. RESULTS: Of 46 patients who completed the study, 17 (37%) were treatment refractory whereas 29 (63%) were treatment responsive. At baseline, the treatment refractory group had a significantly longer mean duration of disease (P = 0·02) and mean duration of oral lesions (P = 0·01), a higher percentage of lesions in the retromolar trigone (P = 0·05) and on the occlusion line along the buccal mucosa (P = 0·04), a higher percentage of deep/crateriform ulcers (P < 0·001) and erosions with a lichenoid hue (P < 0·001). Herpes simplex virus (HSV) DNA positivity, assessed by polymerase chain reaction in oral tissue scrapings (P = 0·02), was also significantly higher in the treatment refractory group. No other factors we tested for were statistically significant. CONCLUSIONS: Treatment refractoriness of oral lesions was significantly associated with duration of disease/oral lesions; specific morphology and location of oral lesions; and the presence of HSV DNA in the oral cavity. These factors may forewarn the treating physician about a refractory course of oral lesions that may help with counselling patients.