These heterocontacts provide regions withextremely rapid 7Li NMR spin fluctuations giving directevidence for very fast Li+ jump processes in both nanoconfinedLiBH4/Al2O3 and LiBH4-LiI/Al2O3. Compared to the nanocrystalline, Al2O3-free reference system LiBH4-LiI, nanoconfinementleads to a strongly enhanced recovery of the 7Li NMR longitudinalmagnetization. The fact that almost no difference is seen betweenLiBH4-LiI/Al2O3 and LiBH4/Al2O3 unequivocally reveals that the overall 7Li NMR spin-lattice relaxation rates are solely controlledby the spin fluctuations near or in the conductor–insulatorinterfacial regions. Thus, the conductor–insulator nanoeffect,which in the ideal case relies on a percolation network of space chargeregions, is independent of the choice of the bulk crystal structureof LiBH4, either being orthorhombic (LiBH4/Al2O3) or hexagonal (LiBH4-LiI/Al2O3). 7Li (and 1H) NMR shows thatrapid local interfacial Li-ion dynamics is corroborated by rathersmall activation energies on the order of only 0.1 eV. In addition,the LiI-stabilized layer-structured form of LiBH4 guaranteesfast two-dimensional (2D) bulk ion dynamics and contributes to facilitatingfast long-range ion transport.Synthesizing Li-ion-conductingsolid electrolytes with application-relevantproperties for new energy storage devices is a challenging task thatrelies on a few design principles to tune ionic conductivity. Whenstarting with originally poor ionic compounds, in many cases, a combinationof several strategies, such as doping or substitution, is needed toachieve sufficiently high ionic conductivities. For nanostructuredmaterials, the introduction of conductor–insulator interfacialregions represents another important design strategy. Unfortunately,for most of the two-phase nanostructured ceramics studied so far,the lower limiting conductivity values needed for applications couldnot be reached. Here, we show that in nanoconfined LiBH It is strongly anticipated that these two approaches lead to fundamentallydifferent diffusion mechanisms. While anion substitution in LiBH4-LiX  stabilizes the highly conductive hexagonalphase at much lower temperatures than Tpt,15 through nanoconfinement, a large fractionof Li+-ion conductor–(ionic)insulator interfacialregions are introduced, which are suggested to be responsible forincreased long-range ion transport. A definite proof of the latterconcept or effect is, however, still missing for the LiBH4/Al2O3 composites. For LiBH4/SiO2 nanocomposites, the important role of surface groups hasbeen discussed recently.17Two approaches have been establishedand presented in the literaturethat successfully enhance the room-temperature ionic conductivityof LiBH–-ion-conductingBaF2 and CaF2 with thicknesses of 9 nm, whichwere grown by molecular beam epitaxy.18 The foundations of space charge zones in such nanostructured artificialion conductors were laid by Maier,22 explaining such nontrivial sizeeffects that rely on overlapping space charge zones. CuBr/Al2O3(TiO2) composites, as studied by Knauth andco-workers,23 belong to another group ofsuch composites that show enhanced electrical conductivity.25In general, heterocontactsbetween two different phases, viz.,an ion conductor and an insulating phase, or even between two (mixed)conductors, may generate a percolation network of space charge regionswith enhanced charge carrier mobility. The most prominent two-phasesystem is composed of alternating layers of F2O3.26 Later, for the nanocrystalline system Li2O/X2O3 , similar effects28 were observed by 7Li NMR SLR rate measurements.30 Although enhanced Li+ diffusivity was probed, the resultingconductivities28 could not reach any practicalbenchmark needed to realize all-solid-state batteries equipped withceramic electrolytes.In the case of Li-ion conductors, Liang observed increasedionicconductivities in samples of LiI/Al4-LiI/Al2O3 andLiBH4/Al2O3, both showing ionic conductivitiesin the orderof 10–4 S cm–1,31 which is by more than a factor of 100 higher than in orthorhombicLiBH4.13 To understand the syntheticapproaches and their impact on overall ionic transport, the role ofthe conductor–insulator interface in achieving such high conductivitiesneeds to be studied in detail. Preferably, such studies should includespectroscopic methods32 being sensitiveto local Li+ hopping processes in or near these interfacialareas. Here, we used 7Li NMR spectroscopy to quantify theeffect of the conductor–insulator interfacial regions in nanoconfinedLiBH4-LiI/Al2O3 and LiBH4/Al2O3 prepared by melt infiltration. Althougha recent 27Al NMR study in our labs suggested that (unsaturated)penta-coordinated Al centers near the Al2O3 surfaceregions are involved in creating a defect-rich LiBH4/Al2O3 interface,33 theultimate proof via 7Li NMR SLR measurements is still missing.In the present study, we directly compared the 7Li (and 1H) NMR response of longitudinal SLR of LiBH4(-LiI)/Al2O3 with those of bulk LiBH4 and LiI-stabilizedLiBH4. We observed a tremendous effect of the insulatorAl2O3 on 7Li NMR SLR, which is directlyproportional to the diffusive motions of the Li+ ions,clearly showing the superior role of conductor–insulator regionsin solid electrolytes with nanometer-sized dimensions. Only in suchsamples, the volume fraction of these regions is large enough to havea dominant effect on overall ion transport properties.This situation is, however, differentfor nanoconfined LiBH4/Al2O3 and LiBH4-LiI/Al2O3, were preparedvia melt infiltration; LiBH4-LiI served as a referencecompound. A detailed description of the corresponding procedure34 as well as of the preparation and characterizationof the composites31 can be found elsewhereas the same samples were used for earlier studies. Ionic substitutionwas realized in a molar ratio of 80:20 (LiBH4/LiI). Thesamples were kept at 295 °C for 30 min under 50 bar H2 pressure in a stainless steel high-pressure autoclave (Parr). Theaverage diameter of the pores in Al2O3 is inthe order of 10 nm.31 As mentioned above,at room temperature, bulk LiBH4 crystallizes with orthorhombicstructure and transforms into its hexagonal phase at temperatureshigher than 110 °C; the corresponding X-ray diffraction patternsare shown in Figure S1. Here, results fromdifferential scanning calorimetry (DSC), see Figure S2, reveal that the corresponding signal of LiBH4/Al2O3 splits into two peaks at 103 °Cand 114 °C; the signals are significantly decreased comparedto the expected one of bulk LiBH4, which was found at 117°C. We do not observe any diagnostic DSC signals pointing toa phase change in LiBH4-LiI/Al2O3 as for LiBH4-LiI, the hexagonal modification is stabilizedby the introduction of LiI already at lower temperatures. For thesake of completeness, LiBH4-LiI shows a slight endothermicsignal at −19 °C. The thermal behavior of LiBH4/Al2O3 is useful when interpreting the diffusion-induced 7Li NMR data, which were collected as follows.The composite electrolytesinvestigated here, i.e., LiBH7Li (and 1H) NMR 1/T1 SLR rates were measured with a Bruker Avance III 300 spectrometerthat is connected to a 7-Tesla cryomagnet. The corresponding Larmorfrequencies were 116 MHz for 7Li and 300 MHz for 1H. All samples were smoothly hand-pressed in Duran tubes under protectiveatmosphere and sealed. Relaxation rates were determined at temperaturesranging from −100 to 200 °C with an increment of usually20 °C. In the region of the diffusion-induced rate peaks, additional 7Li NMR 1/T1 rates were recordedevery 10 or 5 °C. The laboratory-frame 7Li (and 1H) NMR 1/T1 rates were acquiredwith the well-known saturation recovery pulse sequence; dependingon temperature, the 90° pulse lengths (200 W) varied from 2.5to 2.9 μs (7Li) and from 1.1 to 3.3 μs (1H). Usually four to eight scans were accumulated to obtaina single free induction decay. For a detailed description of the pulseprograms used and for a discussion of the procedure employed to parameterizethe longitudinal NMR transients , we refer to our previous study.33Variable-temperature 36 We took thestructural information from published synchrotron X-ray powder diffractiondata.37 The softBV software executes astructure plausibility check, calculates surface energies, and givesinformation about the positions of interstitial sites and saddle points,as well as the topology and dimensionality of ion-migration pathsand the respective migration barriers.36 For the calculations,Li+ was chosen as the mobile ion and the grid resolutionwas set to 0.1 Å. Pros and cons of the approach via softBV arediscussed elsewhere.36 For the visualizationof the data, we used the VESTA software package.38We also performed bond valence site energy estimationscombinedwith a bond valence pathway analyzer using the softBV software tooldeveloped by Adams and co-workers.4 crystallizes either with orthorhombic or with hexagonal symmetry.At temperatures lower than Tpt = 110 °C,the poorly conducting orthorhombic modification is present  jump processes in the layer-structuredformof LiBH4. This dynamic process, which is 2D in nature asis illustrated in 7Li NMRrate peaks appear if the motional correlation rate 1/τc, which is expected within a factor of ca. 2 to be identicalwith the jump rate 1/τ, reaches the order of the (angular) Larmorfrequency ω0.11 At thetemperature where the peak appears, the condition ω0τ ≈ 1 is fulfilled.43 A symmetricrate peak is only obtained for uncorrelated and isotropic  diffusion. In many cases, structural disorder combined with Coulombinteractions results in asymmetric NMR peaks whose low-T flank shows a lower slope than that characterizing the flank onthe high-T side.43 Moreover,while the slope in the high-T regime is characteristicfor long-range ion diffusion, the low-T flank ofthe peak is sensitive to short range, that is, local diffusion processes.11Above 4 by the incorporationof LiI leads to several changes of the overall 7Li NMRresponse (see 7Li NMR 1/T1(1/T) rates pass into the low-T flank of the rate peak, which characterizes translational Li+, dynamics already at temperatures equal to or larger than340 K. In agreement with faster Li+ diffusion in LiBH4-LiI, the slope of the low-temperature flank of the rate peakyields an activation energy Ea of 0.36eV  merge into a much broader peak locatedat T ≈ 190 K. Most likely, this change originatesfrom a broader distribution of rotational jump rates in LiBH4-LiI. The shift toward lower temperatures agrees with a reductionof the activation energies Ea associatedwith the BH4– rotational jumps. Here, Ea decreases from 0.26 to 0.12 eV if we considerthe high-T flank of the 7Li NMR rate peaksjust below Tpt  showed some subtle differences in this temperature regime (seethe Supporting Information). As suggestedby Figures S4 and 4(-LiI)/Al2O3 compared to those in the bulk regions of LiBH4.7Li NMR spin-lattice relaxation is seen at highertemperatureswhen Li+ translational ion dynamics start to govern thespin fluctuations  ball milling.13 Melt infiltration leaves behind a defective LiBH4 phase, and we assume tight conductor–insulator contacts.The nanoconfined samples provide a large fraction of these heterocontacts.Our comparative NMR results clearly show that the interfacial regionsplay a dominant role in explaining enhanced ion dynamics in the nanoconfinedsamples regardless of whether LiI is present or not. The latter findingis supported by recent calculations revealing that the poor ion transportin orthorhombic LiBH4 originates from very high defectformation energies.8 The LiBH4/Al2O3 zones are, however, expected to be richin defects, thus facilitating ion transport.33 A similar effect has been described very recently by first-principlescalculations for the interface in LiBH4/MoS2 composites.44 Importantly, in LiBH4/SiO2 composites, the role of surface groups shouldnot be underestimated.17 Surface effects are also importantfor LiBH4/Al2O3: as has been shownquite recently by 27Al NMR,33 penta-coordinated Al centers AlIV get saturated whilegenerating AlIVBH4––Li+, forming a defect-rich zone with vacant or interstitial Li+ sites. The same mechanism has also been proposed by someof us for the recently studied LiF/Al2O3 nanocrystallinecomposites.45Here, this effect turnedout to be much larger than that seen forLiBH7Li NMR rates of the two nanoconfinedAl2O3-containing samples (see 4 (0.18 eV) prepared by ball milling.46 Values in the order of 0.07 eV were also observed indirectlyby 1H NMR SLR measurements above 380 K . Again, weascribe the reduction in activation energy when going from nanostructuredLiBH4 to nanoconfined LiBH4/Al2O3 to the interfacial “insulator effect” generatinga percolation network of fast diffusion pathways for the Li+ ions. Most likely, as detailed above, such a network benefits fromdefect-rich space charge regions that influence the Li+ hopping processes.Up to 330 K, the ples see 2b followT1 ratesof nanoconfined LiBH4/Al2O3 leveloff near 373 K and passinto a region that is characterized by a very low activation energy.As the addition of LiI stabilizes the hexagonal phase at temperatureswell above room temperature, the anisothermic peaks are virtuallyabsent. Again, this comparison shows that it is not the crystal structurebut rather the interaction with the Al2O3 interfacesthat governs ion dynamics in the interfacial regions of the nanoconfinedcomposite samples below the phase transition temperature. Our resultsshow how this effect can be used to turn a poor ion conductor, suchas orthorhombic LiBH4, into a superior material with fastLi+ exchange processes assisting in facile macroscopicionic transport (see below).The 1/T flank of thegiven 1/T1(1/T) ratepeak, are sensitive to the elementary hopping processes, NMR lineshapes, which are governed by spin-spin-relaxation rates, can be usedto probe Li+ transport on longer length scales. To seewhether and to which extent the conductor–insulator effectdoes also affect the corresponding 7Li NMR lines, we recordedvariable-temperature spectra of the reference sample LiBH4-LiI  with a nonvanishing electric fieldgradient (EFG) at the nuclear site. This interaction alters the Zeemanlevels such that for I = 3/2, four inequivalent levelsare generated that depend on the crystallite orientation in the externalmagnetic field. Assuming an (averaged) axially symmetric EFG at thenuclear sites, the corresponding quadrupolar coupling constant Cq of the powder sample is given by Cq = 32 kHz.7Li NMR ratesstart to increase. Satellite singularities come into the picture at313 K. Already at 294 K, approximately 50% of the Li+ ionsin LiBH4-LiI/Al2O3  motional narrowingdoes already set in at temperatures lower than 250 K. This temperatureagrees with the temperature at which the l2O3 see 3b have a94 K see 3c.33 the overall couplingconstant Cq (≈ 20 kHz) turned outto be clearly reduced compared to that of LiBH4-LiI. Importantly,for LiBH4/Al2O3, almost the sameline shapes are detected as for the LiBH4-LiI/Al2O3. Again, this result demonstrates the leading role ofAl2O3 in governing the 7Li NMR signals.Motional narrowing is slightly shifted toward higher T, which is in excellent agreement with the temperature behavior ofthe 7Li NMR rates. The corresponding coupling constant Cq = 23 kHz of LiBH4-Al2O3 resembles that of LiBH4-LiI/Al2O3; see also the magnified spectrum recorded at 433 K. Moreover, at a given temperature,the associated 1/T17Li NMRrates of the fast and slowly decaying part of the underlying freeindication decays do almost coincide. Hence, we conclude that forthe nanometer-sized architecture in the conductor–insulatorcomposites, rather efficient spin diffusion is present. Hence, fromthe point of view of SLR NMR, LiBH4 in LiBH4/Al2O3 appears as an almost homogeneous phase.Importantly, fast spin diffusion connecting the two spinreservoirsin the nanoconfined samples causes single exponential + exchange processes in the interfacial regions of the nanocomposites,it is, in the present case, less sensitive to long-range ion transportin LiBH4-(LiI)/Al2O3. While the twosamples LiBH4-LiI/Al2O3 and LiBH4/Al2O3 show almost the same 7Li NMR response, through-going ionic transport in LiBH4-LiI/Al2O3 is easier (ca. 1.3 × 10–4 S cm–1 (298 K))31 than in LiBH4/Al2O3 (0.3× 10–4 S cm–1 (298 K)).31 Most likely, this difference originates fromthe orthorhombic bulk regions in the latter compound that hinder Li+ ion dynamics; see the schematic illustration in 2O/Al2O3 composites, whose heterogeneous transport propertieswere explained by the percolation concept.48 Here, for both compounds, the LiBH4/Al2O3 interface (heterocontacts) provides fast Li+ diffusionpathways. While at low temperatures Li+ diffusion in theorthorhombic bulk regions of LiBH4 in LiBH4/Al2O3 is slow, and only enhanced at the LiBH4/LiBH4 homocontacts, anion substitution in LiBH4-LiI/Al2O3 additionally ensures fast Li+ self-diffusivity in the hexagonal bulk regions that do notbenefit from interactions with the surface regions. Therefore, thecombination of nanoconfinement and anion substitution enables facile,overall Li+ long-range ion transport as it is necessaryfor, e.g., battery applications.33Noteworthy, while NMR is able to monitor the fast Li4 and nanoconfinedLiBH4-LiI asmodel systems, we investigated the influence of conductor–insulatorinterfacial regions on the overall Li+ translational iondynamics, which we sensed by 7Li NMR spin fluctuations.Al2O3 served as an insulating phase, that is,the phase usually blocking Li+-ion transport. As irregulardiffusive motions trigger  7Li NMR spin-latticerelaxation, with the help of variable-temperature measurements, activationenergies and motional correlation rates can be probed.Using LiBH4-LiI rapid Li+ translationalmotions (0.36 eV) influence the 7Li NMRrates 1/T1 at temperatures above 340 K,in the Al2O3-bearing nanoconfined samples, adrastic change in overall NMR response is seen. For LiBH4-LiI/Al2O3, the low-T flankof the corresponding diffusion-induced rate peak 1/T1(1/T) is already seen at a temperatureas low as 240 K, thus shifted by 100 K toward lower temperatures.Surprisingly, above 270 K, the same flank is also seen for the LiI-freesample unequivocally showing that the conductor–insulator (Al2O3) effect has the authoritative role to explainthe enhanced Li+-ion dynamics in these samples. Clearly,reduced activation energies in the order of only 0.1 eV agree withthe low onset temperatures and underpin the idea of a percolationnetwork of fast diffusion pathways generated by the conductor–insulatorinterfacial regions.Whilein nanoconfined LiBH7Li NMR line shape measurementscorroborate the resultsfrom 7Li NMR relaxometry and reveal, for both samples LiBH4-LiI/Al2O3 and LiBH4/Al2O3, an ensemble of mobile Li+ ions beingsubjected to rapid diffusive motions already at temperatures wellbelow ambient. 7Li NMR quadrupole interactions seen inthe spectra of nanoconfined LiBH4/Al2O3 do reflect both bulk and interfacial regions, with the spins inthe latter areas being highly mobile and benefiting from the interactionwith the insulator surface. Our work highlights the importance ofconductor–insulator interfacial regions in advanced solid electrolyteresearch. The clever introduction of such artificial interfaces, influencingion dynamics by both structural disorder and space charge regions,represents an adjustable tool to manipulate overall (Li+)ion dynamics in solids with nanometer-sized dimensions.


Escherichia coli (DEC) strains are common causes of morbidity and mortality worldwide. Waterborne DEC could pose a health risk to humans through domestic use of contaminated water. However, epidemiological studies on DEC in well water are scarce in Nigeria. This study determined the prevalence, diversity and factors associated with the presence of DEC in well water in Ile-Ife, southwestern Nigeria.Diarrhoeagenic E. coli by amplifying their 16S rRNA gene. Five diarrhoeagenic E. coli pathotypes were sought using multiplex polymerase chain reaction (PCR). (GTG)5 repetitive PCR and Shannon diversity index were used to determine isolates diversity. Multivariate analysis was used to reveal the factors associated with the presence of DEC in  well water.We assessed 143 wells for safety and a questionnaire was administered. Contaminating isolates were identified as E. coli. Wells with dirty platforms, undercut by erosion and sited near septic tanks significantly harboured DEC (p <  0.05). There was a preponderance of Shiga-toxin producing E. coli among the isolates with 10 (17.9%) wells contaminated by multiple DEC. The DEC isolates showed 45 unique fingerprints and were divided into six clades, with an overall diversity index of 18.87.Fifty-six (39.2%) wells were contaminated by diarrhoeagenic The presence of DEC in well water highlights the risk to human health associated with the use of untreated water. There was a high degree of genetic diversity among the isolates implying multiple sources of contamination. There is a need for periodic sanitation and inspection of wells for cracks to prevent seepages and possible outbreaks of waterborne diseases. Escherichia coli, a member of faecal coliforms has a significant place in water microbiology as an indicator of faecal pollution and a pathogen in drinking water. As a pathogen, it causes a variety of diseases ranging from urinary tract infections, sepsis, meningitis and bacteraemia to diarrhoea [Diarrhoeal diseases are significant public health problems in developing countries . Each yeiarrhoea .Escherichia coli (DEC) account for about 40% of episodes of acute diarrhoea in children in developing countries. They also play a significant causative role in diarrhoea in Nigeria, in both adults and children. Currently, there are eight pathotypes of DEC strains: enterotoxigenic, enterohaemorrhagic, enteroinvasive, enteropathogenic, enteroaggregative, diffusely adherent, cytolethal distending toxin-producing and cell detaching E. coli. Each pathotype of DEC has a distinct set of virulence factors encoded in the plasmids or chromosome. The genes that encode these factors are conserved among strains that are isolated from diverse sources in different parts of the world [Diarrhoeagenic Escherichia coli can enter drinking water via inadequate or failing septic or sewer systems, runoff from land applied with animal wastes or animal feeding operations and wildlife. Identification of the source of pollution is a high priority in order to protect source water quality and to assess the public health risk associated with contamination from a particular host source. Consequently, much progress has been made over the years to develop many phenotypic and genotypic microbial source tracking (MST) methods which are recommended components of faecal pollution reduction strategies [DEC strains are usually transmitted via a faecal-oral route which involves contaminated sources of water or food and may be involved in outbreaks of waterborne diarrhoea. rategies , 6.Nigeria is one of the countries in the world where about 90 million people don’t have access to potable water and 130,000 children under the age of five die each year from avertable waterborne diseases due to uncoordinated efforts of various agencies of government. The larger part of the population, particularly those in the rural and suburban communities resort to water from wells and streams for domestic purposes , 7. ThosE. coli contaminated water, very little data is available on this in Ile-Ife, and the pathogenic potential, diversity of implicated isolates and factors associated with their presence in well water remain unknown. Therefore this study determined the prevalence, diversity and factors associated with the presence of DEC in well water in Ile-Ife, Southwestern Nigeria.Despite the risk posed by exposure to The study was done in Ife East Local Government Area, Ile-Ife, Osun State, Nigeria. Ife East Local Government Area is divided into six wards which are: Moore ward, Ilode ward 1, Ilode ward 2, Okerewe ward 1, Okerewe ward 2 and Okerewe ward 3. Ile-Ife is an ancient city in southwestern Nigeria with a population of 509, 035 . The citThis study was approved by the Health Research Ethics Committee (HREC), Institute of Public Health, Obafemi Awolowo University, Ile-Ife, Nigeria (HREC No: IPHOAU/12/863). A total of 143 water samples were collected from wells that are distributed across the wards between March and December 2019 based on the formula of Sullivan and Soe [The quality of the samples was determined using the multiple tube fermentation technique as described by Cheesbrough . A threeE. coli in the samples. All positive bottles from the previous test were subcultured into fresh double strength and single strength MacConkey broth and peptone water and incubated at 37 °C for 24 h. The MacConkey bottles were checked after incubation for lactose fermentation (yellow colouration) and gas production (presence of a bubble in the Durham tubes). All positive MacConkey bottles were noted and three drops of Kovac’s reagent were added to their corresponding peptone water bottles to detect indole (indicated by a red coloured ring). All positive samples were cultured on Eosin Methylene Blue Agar plates and incubated aerobically at 37 °C for 24 h. Up to three distinct colonies showing green metallic sheen were aseptically picked and streaked onto Nutrient agar (NA)  plates which were, in turn, incubated aerobically at 37 °C for 24 h [E. coli isolates were stored at -20 °C in glycerol broths for further examination.The Eijkman method was used to detect the presence of for 24 h . All susAll isolates were subcultured from glycerol broths on nutrient agar plates and incubated at 37 °C for 24 h. Three colonies were picked from each culture and suspended in 50μl of sterile distilled water in an Eppendorf tube to extract the DNA of the isolates. The suspension was boiled for 10 min, kept on ice for 10 min, and centrifuged at 10,000 rpm for 10 min . The supE. coli by their phenotypic characteristics were confirmed as E. coli by amplifying their 16S rRNA gene , 2.4 μl of the DNA template and made up with Nuclease Free Water. Amplification conditions were as follows: Initial denaturation at 95 °C for 5 min; 35 cycles of denaturation at 94 °C for 45 s, annealing at 45 °C for 45 s, and extension at 72 °C for 1 min; followed by a final extension at 72 °C for 5 min. Each PCR product (10 μl) was electrophoresed on a 1.5% (w/v) agarose gel in 1X TAE. Gels containing 5ul of 10μg/ml of ethidium bromide were visualized under ultraviolet (UV) light using a UVitec transilluminator .All organisms suspected to be E. coli comprising enteroinvasive E. coli (EIEC), enteropathogenic E. coli (EPEC), enterotoxigenic E. coli (ETEC), enteroaggregative E. coli (EAEC) and enterohaemorrghagic E. coli (EHEC) including shiga toxin producing E. coli (STEC) as described by Aranda et al. [bfpA (bundle-forming pilus of EPEC), stx1 and/or stx2 (shiga toxins 1 and 2 of EHEC and STEC), eltB and/or estA (enterotoxins LT and ST of ETEC), ipaH (invasion plasmid found in EIEC and Shigella) and pCVD (pCVD432 of EAEC). E. coli strains E2348/69, O42, H10407, EDL 933 and E137 served as positive controls for EPEC, EAEC, ETEC, EHEC and EIEC respectively while sterile water was used as a negative control. For PCR 1 : Amplification conditions were as follows: Initial denaturation at 95 °C for 3 mins; 37 cycles of denaturation at 94 °C for 30 s, annealing at 45 °C for 30 s, and extension at 72 °C for 1 min; followed by a final extension at 72 °C for 7 min. For PCR 2 : Amplification conditions were as follows: Initial denaturation at 94 °C for 3 mins; 37 cycles of denaturation at 94 °C for 45 s, annealing at 39 °C for 30 s, and extension at 72 °C for 54 min; followed by a final extension at 72 °C for 7 min. Each PCR product (10 μl) was electrophoresed on a 1.5% (w/v) agarose gel in 1X TAE. Gels containing 5ul of 10μg/ml of ethidium bromide were visualized under ultraviolet (UV) light using a UVitec transilluminator .All isolates were screened for virulence genes characteristic of five pathotypes of diarrhoeagenic a et al.  with mod(GTG) 5-PCR was used to subtype the isolates. PCR was performed with a 25 μl reaction mixture containing 12.5uL 2XMaster mix, 10 pmol each of the primer (5’GTGGTGGTGGTGGTG3’), 2.4 μl of the DNA template and made up with Nuclease Free Water. Amplification conditions were as follows: Initial denaturation at 95 °C for 5 mins; 35 cycles of denaturation at 95 °C for 60 s, annealing at 40 °C for 60 s, and extension at 68 °C for 8 min; followed by a final extension at 68 °C for 8 min. Each PCR product (10 μl) was electrophoresed on a 1.5% (w/v) agarose gel in 1X TAE . Gels coH) formula [The genetic diversity of DEC isolates was calculated using the Shannon diversity index . Cross tables were produced with in water . The P-vEscherichia coli in the study area from 143 wells. The sampling locations are shown on the map in Fig. n = 108; 75.5%), some were partially covered , and a few were not covered . The majority of well owners were Christians , artisans  with secondary education  and lived in tenement . The mean age of the wells was 21 years and the average depth was 29.3 ft.This study investigated water quality and characterized One hundred and ten  wells were contaminated with coliforms bacteria. Ilode ward 2 36; 32.7%) had the highest number of contaminated wells while Okerewe ward 3  had the least number , yielding a total of 69 DEC strains. Okerewe 1(n = 15) had the highest number of wells that were contaminated with DEC, while Okerewe 3(n = 5) had the least number. There was a preponderance of STEC (n = 35) among the strains, followed by ETEC (n = 10). Two and five strains were both STEC/tEPEC and ETEC/STEC respectively. Multiple pathotypes of DEC were recovered from 10 (17.9%) wells.Fifty-six (39.2%) wells were contaminated by diarrhoeagenic Of the wells that were contaminated by DEC, 16 (28.6%) were undercut by erosion, 26 (46.4%) were sited near septic tanks, 24(41.4%) had dirty platforms, 22 (37.9%) were owned by those who keep pets, 39(69.6%) were used by those in a tenement, 19(33.9%) were sited near livestock and 40(71.4%) were owned by artisans. The average age and depth of the wells were 17.5 ± 22.2  and 31.5 ± 23.5  respectively (Table p = 0.018), sited near septic tanks (0.005), had dirty platforms (0.001), owned by those who kept pets (0.035), used by those in tenement (0.012) significantly harboured diarrhoeagenic E.coli.Univariate analysis revealed that wells that were undercut by erosion (p = 0.046), sited near septic tank , had dirty platforms  were significantly associated with the presence of DEC in wells. However, there was no significant association between wells that were owned by those who kept pets  and those used in tenement  and the presence of diarrhoeagenic E. coli 5-PCR fingerprint picture is shown in Fig. In all, the isolates were highly diverse as indicated by Shannon diversity index (H = 18.87). Isolates from Okerewe ward 1 (H = 5.41) were the most diverse while those from Okerewe ward 3 were the least diverse (H = 3.17). Other diversity indices are: Moore (H = 4.93), Ilode ward 1 (H = 4.68), Ilode ward 2 (H = 4.93) and Okerewe ward 2 (H = 4.60).E. coli (DEC) [Diarrhoeal disease is a leading cause of morbidity and mortality in children globally and a high percentage of bacterial gastroenteritis is caused by diarrhoeagenic li (DEC) . In NigeE. coli strains were isolated from 98 out of 110 wells that were contaminated by coliform bacteria. All the isolates were screened for eight different diarrhoeagenic genes possessed by five E. coli pathotypes. We detected DEC in 56 wells in the six wards of the local government area. Our observation aligns with the reports of previous investigators which observed that drinking water can be a reservoir of DEC in the environment [E. coli in drinking water highlights the potential risk for environmental transmissibility of these strains in different parts of the world.In this study, 169 ironment , 24. Theironment  (28.1%) ironment  (33.3%),In order to identify the risk factors associated with the presence of DEC in water in the study environment, we used binomial logistic regression models to test for association. Our analysis revealed a significant association between the presence of DEC and wells that were undercut by erosion, sited near septic tanks and those with dirty platforms. Findings from previous studies have also highlighted these factors to have a significant association with water contamination –29. SitiWe observed that the DEC pathotypes’ prevalence varied according to location, probably due to the prevailing associated factors in each location. Okerewe ward 1 had the highest number of wells that were contaminated with DEC, while Okerewe 3 had the least number. Furthermore, multiple DEC pathotypes were recovered from ten wells in the sampled locations. Previous studies in Burkina Faso , BangladE. coli isolates from water samples in France was STEC [All the five pathotypes of DEC that we sought were identified with a preponderance of STEC. The occurrence of STEC in drinking water has been reported globally , 35; alowas STEC . Intereswas STEC . Therefostx2 which is strongly associated with haemorrhagic colitis and haemolytic uraemic syndrome in humans. Even though eae is a significant determinant of virulence in STEC infection, most of the stx2 -positive isolates did not have it, apart from three isolates that harboured eae with stx2 and stx1. While considering the reported health risk attributable to STEC, the detection of eae-negative STEC strains in our study could be a public health concern as outbreaks of bloody diarrhoea and hemolytic-uremic syndrome (HUS) caused by STEC strains without the eae gene have been reported, which suggests that Shiga toxin is the primary virulence trait responsible for HUS [stx2 gene has been documented to be more strongly associated with severe disease in humans than the stx1, thus, signifying its importance in human infection.Most of our STEC harboured  for HUS , 36. BesE. coli isolated from water were ETEC which differs from the prevalence of 14.5% we got in our study, but higher than Rodrigues da Silva et al. [ETEC, EAEC, EPEC have been linked with waterborne outbreaks of gastroenteritis. In our study, ETEC was second to STEC in terms of prevalence. Kambire et al.  found tha et al.  that repa et al. . In thisa et al. . The EPEa et al.  and Sidha et al.  detectedE. coli pathotype that causes watery diarrhoea and dysentery similar to Shigella in terms of pathogenesis. In this study, EIEC was detected in four (5.8%) DEC isolates. Compared with our findings, higher prevalence rates of EIEC have been reported from China (9.1%) [EIEC is an important a (9.1%)  and Sudaa (9.1%)  probablyE. coli pathotypes isolated from some water samples: STEC and tEPEC (N = 2/56) (3.6%), ETEC and STEC (N = 5/56) (8.9%), tEPEC, ETEC and STEC (1/56)(1.8%), EAEC and tEPEC (1/56) (1.8%). Remarkably, this is the first study to report these combinations in waterborne DEC isolates. Other studies reported a different combination of genes from both EAEC and EHEC [Moreover, our results showed two and three combinations of diarrhoeagenic genes of different and EHEC , 46. ThiE. coli with a short generation time interval as well as easy acquisition of mobile genetic elements under selection pressure provides a greater degree of genetic diversity among E. coli strains. The extensive diversity among the DEC strains isolated from different sources largely rules out between/within location transmissibility of isolates. Likewise, several independent studies have reported the existence of diverse populations of E. coli in several hosts and environments [There have been reports on the prevalence of DEC pathotypes in healthy and diseased individuals from Nigeria; however, there is a paucity of waterborne DEC studies that reveal the relatedness of isolates according to their sources of isolation. Therefore, to determine the degree of diversity among DEC pathotypes, all isolates were subjected to (GTG)5 rep-PCR typing, a genotypic technique for the detection of diversity. In our study, complex fingerprint patterns were obtained for all DEC isolates. In addition, all the DEC isolates clustered together with six clades of strains observed. Generally, we obtained a diverse profile among and between the isolates recovered from different sources. The highly adaptive nature of ronments . Clade 5E. coli in drinking water highlights the risk to human health associated with the use of untreated water. There was a high degree of genetic diversity among the isolates implying multiple sources of contamination thus emphasizing the need for periodic sanitation and inspection of wells for cracks to prevent seepages, runoff and possible outbreaks of waterborne diseases. Also, there is a need to sensitise well owners and consumers to inculcate the habit of boiling untreated water before use. Regulatory agencies in charge of well construction and water quality must take the appropriate measures to ensure proper well siting, construction, and maintenance to prevent contamination.This study reports a high prevalence of DEC in well water with a preponderance of STEC. The presence of these pathogenic strains of


This survey study assesses the factors associated with continued use of telehealth services, including experience with, cost of, and benefits or barriers to video-based clinician visits among adult patients. What role do US adults envision for telehealth in their future medical care?In this survey study of 2080 adults, most respondents were willing to use video visits in the future but, when presented with the choice between an in-person or a video visit for nonemergency care, most preferred in-person care. Willingness to pay for preferred visit modality was higher for those who preferred in-person care, and those who preferred video visits were more sensitive to out-of-pocket cost.The findings of this study suggest that awareness of patient preferences will help define telehealth’s role in US health care after the COVID-19 pandemic. Telehealth use greatly increased in 2020 during the first year of the COVID-19 pandemic. Patient preferences for telehealth or in-person care are an important factor in defining the role of telehealth in the postpandemic world.To ascertain patient preferences for video visits after the ongoing COVID-19 public health emergency and to identify patient perceptions of the value of video visits and the role of out-of-pocket cost in changing patient preference for each visit modality.This survey study was conducted using a nationally representative sample of adult members of the RAND American Life Panel. The data were obtained from the American Life Panel Omnibus Survey, which was fielded between March 8 and 19, 2021.Preferences for video visits vs in-person care were analyzed in the survey. The first question was about participants’ baseline preference for an in-person or a video visit for a nonemergency health issue. The second question entailed choosing between the preferred visit modality with a cost of $30 and another modality with a cost of $10. Questions also involved demographic characteristics, experience with video visits, willingness to use video visits, and preferences for the amount of telehealth use after the COVID-19 pandemic.A total of 2080 of 3391 sampled panel members completed the survey . Participants in the weighted sample had a mean (SE) age of 51.1 (0.67) years and were primarily women (1079 [51.9%]). Most participants (66.5%) preferred at least some video visits in the future, but when faced with a choice between an in-person or a video visit for a health care encounter that could be conducted either way, more than half of respondents (53.0%) preferred an in-person visit. Among those who initially preferred an in-person visit when out-of-pocket costs were not a factor, 49.8% still preferred in-person care and 23.5% switched to a video visit when confronted with higher relative costs for in-person care. In contrast, among those who initially preferred a video visit, only 18.9% still preferred a video visit and 61.7% switched to in-person visit when confronted with higher relative costs for video visits.This survey study found that participants were generally willing to use video visits but preferred in-person care, and those who preferred video visits were more sensitive to paying out-of-pocket cost. These results suggest that understanding patient preferences will help identify telehealth’s role in future health care delivery. A nationally representative survey from 2020 found that 40% of patients with a health condition used telehealth in the spring of 2020.6 Surveys from before the COVID-19 pandemic found that 49% to 66% of the respondents were interested in using video visits, with greater preference for telehealth when seeing their own clinician vs a new clinician.10 Although numerous studies have shown that patients are satisfied with telehealth and appreciate its convenience,13 data are scarce on the role that patients would like telehealth to play in their overall care, including within hybrid care models, and the perceived value of telehealth compared with other visit modalities. Such information is key to understanding the implications of different coverage and reimbursement policies, including cost sharing, for the demand for telehealth and the potential backlash of rolling back the telehealth flexibilities that were implemented for the COVID-19 pandemic.Payers are currently making decisions about postpandemic reimbursement policy and considering telehealth’s implications for quality, costs, fraud, and abuse. These decisions are informed by claims data analyses of telehealth utilizationWe conducted a nationally representative survey study using conjoint analysis, a technique in which respondents make hypothetical choices between alternatives that vary in 1 or more attributes, to ascertain patient preferences for video visits after the ongoing COVID-19 public health emergency. Specifically, we sought to identify patient perceptions of the value of video visits and the role of out-of-pocket cost in changing patient preferences for each visit modality. We also asked participants about their willingness to use video visits in the future and their preferences for the amount of video visits that they will incorporate in their medical care after the COVID-19 pandemic.14 The survey was approved by the RAND Institutional Review Board, which waived the informed consent requirement because the American Life Panel survey data collection fell under the adult interview and survey exemption. We followed the American Association for Public Opinion Research (AAPOR) reporting guideline.We conducted this survey using the RAND American Life Panel, which produces nationally representative estimates from a probability-based representative sample of the US adult population aged 20 years or older.15 Participants have been recruited from other nationally representative probability-based panels, sampling in zip codes with high percentages of racial minority groups, and random digit dialing.15 Panel participants are given internet-connected devices and are paid for completing surveys. For the present survey study, the data were obtained from the American Life Panel Omnibus Survey, which was fielded between March 8 and 19, 2021. Weights are generated through a raking process using the demographic data of participants  rather than the national estimates of these variables in the Current Population Survey Annual Social and Economic Supplement.15The American Life Panel recruited its first wave of participants in 2002 and is continually refreshed to create a total current panel size of approximately 6000 participants.We hypothesized that some people would prefer in-person care and others would prefer video visits. Thus, we asked respondents first about their baseline preference for an in-person or a video visit for a nonemergency health issue that their personal physician indicated could be handled through either visit modality. Given that telehealth is an umbrella term and can include telephone visits, video visits, store-and-forward encounters, and remote patient monitoring, we narrowed the scope of the questions by specifying video visits.16 The cost difference of $20 was used to assess the relative value placed on each visit modality. We also asked questions about demographic characteristics, experience with video visits, willingness to use video visits, and preferences for the amount of telehealth use after the COVID-19 pandemic. Participants self-reported their race and ethnicity, choosing from a set of options defined by the American Life Panel survey investigators. For ethnicity, the question was, “Do you consider yourself Hispanic or Latino?” with a yes or no option. For race, the question was to choose from these options: White/Caucasian, Black/African American, Asian or Pacific Islander, American Indian or Alaska Native, or other race. We assessed race and ethnicity to identify potential disparities in access to telehealth and to capture any differences in preferences for future use of telehealth. Visit modality–related questions are shown in the eTable in the For those who expressed a preference for either an in-person or a video visit, we posed a second question, offering their preferred modality for an out-of-pocket cost of $30 or the other modality for an out-of-pocket cost of $10, and asking which option they preferred. These costs were selected because they represent the lower and higher bounds of typical co-payments for outpatient visits.17 We calculated descriptive statistics  and cross-tabulated frequencies and percentages. We used Rao-Scott χ2 tests for bivariate comparisons of in-person or video visit preferences by demographic variables  and for adjusted logistic regression analyses of binary outcomes of telehealth preferences after the COVID-19 pandemic by demographic variables . Missing data were limited  and likely random; entries with missing values were dropped from the adjusted analyses.We used the American Life Panel response weights to produce nationally representative estimates of answers to the survey questions.P < .05.Analyses were conducted using SAS/STAT software, version 9.4 of the SAS System for Linux (SAS Institute). The threshold for statistical significance was a 2-sided Of the 3391 sampled panel members, 2080 completed the survey, for a 61.3% participation rate. Of the final weighted sample 51.9% of participants were women (n = 1079) and 48.1% were men (n = 1001), with a mean (SE) age of 51.1 (0.67) years. Among the participants, 18.2% self-identified as Hispanic/Latino, 11.8% as non-Hispanic Black/African American, and 63.8% as non-Hispanic White/Caucasian. Complete weighted demographic characteristics of the panel are described in P < .001). In comparison, of the participants without experience with video visits, 60.2% preferred an in-person visit and only 12.2% preferred a video visit (P < .001)  .P < .001). Individuals with higher income were also more likely than those with lower income to prefer video visits. Among individuals making under $35 000 per year, 55.1% preferred in-person visits and 16.0% preferred video visits (P < .001). Meanwhile, of the participants making more than $100 000 per year, 44.0% preferred in-person visits and 26.5% preferred video visits (P < .001)  .P = .02), and Hispanic/Latino respondents were more likely to prefer video visits compared with individuals from other racial and ethnic groups . Differences in modality preferences by race and ethnicity were statistically significant. Educational level was also associated with preferences for video visits, with 64.4% of respondents who did not complete high school preferring in-person care compared with 55.6% of high school graduates and 46.7% of college graduates (P = .03). Conversely, 24.5% of respondents with a bachelor’s degree or higher preferred video visits compared with 17.8% of those who did not complete high school and 18.8% with a high school diploma (P = .03). These differences were statistically significant.Black/African American respondents were more likely than respondents of other races and ethnicities to prefer in-person care  when out-of-pocket cost was not considered were asked about their preferences for a more expensive in-person visit ($30) and a less expensive video visit ($10) . When faced with this scenario, 548 participants (49.8%) still preferred an in-person visit, 259 (23.5%) switched and preferred a video visit, and 295 (26.8%) did not have a preference or did not know .Those participants who preferred video visits (weighted n = 434) when out-of-pocket cost was not a factor were asked about their preferences for a more expensive video visit ($30) and a less expensive in-person visit ($10). When faced with this scenario 82 participants (18.9%) still preferred a video visit, 268 (61.7%) switched and preferred an in-person visit, and 83 (19.1%) did not have a preference or did not know . For botUsing these stated preferences, we explored participants’ willingness to pay for their preferred visit modality for nonemergency visits in the general population . Of the P < .001), as were younger age  and having a higher family income. Lower family income was associated with lower likelihood of wanting at least some (vs no) video visits .When all participants were asked how much of their medical care they wanted to receive through video visits after the COVID-19 pandemic, 731 (33.5%) preferred all of their care to be in person and 1348 (66.5%) wanted at least some video visits  . The oddIn this survey of a nationally representative sample, we found a general willingness to use video visits among US adult respondents. However, when faced with a choice between an in-person or a video visit for a nonemergency health issue, participants generally preferred in-person care, and those who were younger, had higher income, and had a higher educational level were more likely to opt for video visits. Experience with telehealth was associated with preference for video visits, and only 2.3% of those who had participated in a video visit were unwilling to do so again. This finding suggests that, although many participants used telehealth for the first time during the COVID-19 pandemic out of necessity, their experiences were beneficial enough to encourage ongoing use.18 Further research is needed to explore the reason that certain patients are not interested in hybrid care models, which combine in-person and video visits. For example, it is not clear whether these patients simply do not value telehealth as much as in-person care or do not view telehealth as feasible or practical given their personal circumstances .19Only 33.5% of participants did not see any role for video visits in their medical care. These respondents were generally older, had lower income, lived in more rural areas, and had lower educational level. Although telehealth can expand access to care for underserved populations  if deployed in a targeted manner, findings of this survey suggest that these populations may be the least likely to demand it and that ongoing efforts to promote equity of access to telehealth need to consider these preferences.21 Patients may perceive that in-person visits allow for easier referrals for diagnostic testing. Alternatively, some patients may perceive benefits to in-person care that even the highest quality telehealth visit cannot replicate , outweighing the additional costs associated with in-person care .Those who preferred in-person care in the choice task had a higher willingness to pay for their preferred visit modality compared with those who preferred video visits. Those who preferred video visits were more sensitive to out-of-pocket cost than those who preferred in-person visits, as a $20 increase in cost was associated with switching from video visits to in-person care. This difference in perceived value has many potential explanations. Patients may like telehealth in certain circumstances  but may not perceive video visits to have the same value as in-person care. For example, they may not believe that clinicians are able to offer an equivalent service or are putting in as much clinical effort.This survey study, to our knowledge, was among the first efforts to explore the value of different visit modalities in the US population and provide important insights into the role that telehealth can play after the COVID-19 pandemic. Although improving the delivery of telehealth is important, it is only part of the story. Awareness of patient preferences will help to identify telehealth’s role in postpandemic health care delivery.This study has some limitations. First, with the limited conjoint questions that we asked participants, we were unable to conduct a full willingness-to-pay analysis to identify the mean willingness to pay for each visit modality, but we were able to provide some insight into the general value that a nationally representative sample ascribes to each visit modality. Second, the stated preferences approach also had limitations. Respondents may be unfamiliar with making choices between hypothetical options and may have never had to choose between telehealth and in-person care in the past. Third, we were limited in what demographic data were available from the American Life Panel. For example, data on health status were lacking in the American Life Panel Omnibus Survey. Respondents with poor health status may be more or less interested in video visits than those with good health. In addition, respondents may have certain health conditions that make video visits more or less feasible. For example, patients with stable chronic conditions that can be managed through prescription medications, such as diabetes, may be easier to manage than patients with health conditions that require physical examinations, such as cardiac disease. However, lack of such data was not a major limitation given that the goal of this study was to produce nationally representative estimates of preferences. The absence of unmeasured potential confounders did not affect the ability of the study to produce those estimates.This survey study found that adult respondents were generally willing to use video visits but preferred in-person care to a video visit for a nonemergency health issue. Previous use of telehealth was associated with preference for video visits, and those who preferred video visits were more sensitive to out-of-pocket cost. Awareness of patient preferences will help to identify telehealth’s role in postpandemic health care delivery.


Patients often confuse the role of the radiologist with that of the technician. The aim of this study is to explore patients’ current perceptions about the radiology department and to evaluate how it’s possible to get rid of misconceptions using informative animated video in the waiting room.www.makeradiologyvisible.com). The remaining patients did not watch the video.In this multi-centric study , 278 patients of all ages and education levels were surveyed in the radiology waiting room. 107 patients filled out the survey after watching an informative animated video  in the non-video group believe the radiologist “performs the scanning”, compared to 19% (20/107) in the video group (p < 0.001). Patients who think their own physician will interpret the images is 36% (61/171) in the non-video group and 10% (11/107) in the video group (p < 0.001). In the non-video group, 32% (55/171) believe the technician performs the exam compared to 59% (63/107) in the video group (p < 0.001). After the video, 67% (72/107) of patients have more respect for the work of the radiologist, 52% (56/107) experience less anxiety and 65% (70/107) think the video is of added value to their visit. All items showed a better impact in high-educational subgroups.Animated informative videos help to increase patient knowledge about the radiology department. It moderates expectations, reduces anxiety, and ameliorates the overall experience. Although, the learning curve is steeper in highly educated patients, all educational levels benefit. Throughout history, the diagnostic radiologist has developed an increasing distance from the patient . BecauseOne can expect that patients will better comply to medical advice if the medical qualifications of the radiologist are well understood. Likewise, patient care (or the perception of care) could be impacted because the radiologist’s medical qualifications are misunderstood . BesidesWe hypothesized that an informational animated video could help educate patients in the radiology waiting room about the specific role of the radiologist in their care. We created a two-minute animated video in which we walk the patient through the radiology process. In this study, we investigated the impact of such a video on patient knowledge about the job of radiologist/technician. We examined whether the learning curve depended on patient educational levels.Figure 1). The survey was not conducted in ultrasound waiting rooms as these exams are performed by the radiologist in Belgium. The goal of the study is to teach patients a basic understanding of who performs medical exams (the technician) and who interprets the images (the radiologist).A total of 278 patients  were surveyed in our study conducted in two different hospitals in Belgium . Every patient who presented to the Magnetic Resonance Imaging (MRI), Computed Tomography (CT) and X-ray waiting rooms, willing and able to fill out the survey was included. The inclusion criterion was an average knowledge of the Dutch language in order to understand all questions. The survey was filled out on portable tablets to reach every age group. In our experience, all ages feel more comfortable with this technology compared to computers (www.makeradiologyvisible.com.)First, patients were surveyed without a video playing. On a different day, a non-intrusive, muted, animated, informative video was shown on a wall-mounted TV in loop, in the radiology waiting room. In the video, are explained the consecutive steps patients go through when having an imaging exam. We explain that the patient will be called out by a technician to the exam room. Afterwards, technicians will position and guide the patient during the exam and produce all the images in close contact with the supervising radiologist. Patients are told they would ask the technician to meet the supervising radiologist if necessary since, they will not likely need to meet him otherwise. After the exam, all data are sent to the diagnostic radiologist who will interpret the images, make a diagnosis, and issue a report. The video explains that a radiologist is a certified medical doctor with an additional five-year specialization in medical imaging interpretation after the master’s degree in medicine. Lastly, a short fragment of the video teaches patients about the work behind the scenes as the diagnostic radiologist interacts with other medical specialists that are also interventional radiologists.  and a “video group” of 107 patients (38.5%). Why some patients did not see the video when it was playing was beyond the scope and the intent of this study. Plausible reasons are smartphone usage and short radiology waiting times. Nobody was actively asked to look at the video. The video group was additionally questioned on their appreciation of the video and what influence it had on their visit.The data collection was anonymous and only non-specific demographic data were obtained . Multiple-choice questionnaire in the survey included the following:– Did you see the animated video play?– Who performs the exam?– What is the qualification of the radiologist?– What are the core tasks of the radiologist?– How long (after high school) does it take to become a radiologist?– What education does a radiologist have?– What is the role of the radiologist in your care?– Do you expect to meet the radiologist?Patients who watched the video received those additional questions:– Were you more at ease prior to the exam, because of the video?– Was the video of added value for your visit?– Do you feel more respect for the job of the radiologist after watching the video?Ethical evaluation and approval were obtained from the OBC of the Catholic University of Leuven, Belgium (File number: MP015121). To measure the changes in patient understanding about the role of the diagnostic radiologist, results were computed and analysed using Qualtrics. Proportions are given in percentages and compared using chi-squared tests.In the non-video group, 43% (73/171) of patients select “taking X-rays” and 50% (86/171) select “performing scans” as core tasks for the radiologist. In the video group, that number lowers respectively to 14% (15/107) and 19% (20/107) . Only half of the patients  in the non-video group know that radiologists have a “full medical degree”, whereas the video group patients realise radiologists are doctors in a higher frequency .Table 1).Further, in the non-video group, 66% (113/171) patients know that part of the radiologist’s job is to interpret the images and report the findings, whereas in the video group that number rises up to 94% . Only 32% (55/171) know that the exam will be conducted by technicians, and in the video group this number almost doubles to 59% . 36% (61/171) of patients in the non-video group believe the referring physician does the imaging interpretation and in the video group this frequency drops to a mere 10% . In the non-video group, 47% (81/171) expect to meet the radiologist compared to 30%  in the video group (Table 2).Out of 278 patients, 243 provided information about their educational level; 53% (142) of patients had a maximum educational level of a high school diploma (“the less-schooled group”); 38% (101) had a higher degree of education (“the well-schooled group”). Both educational groups show a similar percentage of patients in the video-group .In the non-video group, 35% (30/87) of the less-schooled patients are correctly informed about the medical qualifications of the radiologist, compared to 39% (24/61) in the well-schooled group. After watching the video, 43% (24/55) of the less-schooled  and 70% (28/40) of the well-schooled  patients answered correct  of the less-schooled check the “>10 years” box, compared to 10% (6/61) in the well-schooled group. After seeing the video, 26%  of the less-schooled group answers correctly, a moderate increase. The well-schooled group now answers correctly in 63%  of cases. Again a steeper increase (+53% compared to +16% in the less-schooled group).When asked if the radiologist has a master’s degree in medicine, 45% (67/148) in the non-video group answers correctly, in the video group 73% (69/95) answers correctly (p < 0.001), this equals +32% in the well-schooled group compared to +18% in the less-schooled group.Figure 3).The video group is further evaluated on the use of method for information transfer (animated video). Almost all 94% (100/107) perceives a better understanding of what a radiologist is and does. Nearly half of patients 52% (56/107) have less pre-exam anxiety and feel more at ease in the waiting room. Most patients 65% (70/107) reacted fondly on the extra information and the format in which it was presented, for them it was of added value for their visit. Most strikingly, 67% (72/107) of the patients feel more respect towards the radiologist solely due to the video/obtained knowledge, without having to meet a radiologist . When compared the study of O’Mahony et al. [For the above reasons we opted to produce a modern animated y et al. , BelgianCaution is needed when comparing our results with the study of O’Mahony et al.  because It is also plausible that our patients have a better understanding of the role of the radiologist compared to those in the UK where the technician is named “radiographer” which could be confusing given this term similarities with the word “radiologist”. The Dutch word for a technician meanwhile is a literal translation of “image-maker” that quite obviously explains the job content and therefore causes less confusion.Different patients were surveyed in the non-video versus the video group . Therefore, we cannot objectify a person-based learning curve. Population-wide interpretation of the results can be justified given the consistent outcomes in both institutions .According to this study, animated informative video in the radiology waiting room helps getting rid of misconceptions about the role of the radiologist and the technician in all educational levels, although well-schooled patients benefit more. Animated informative video is of added value for a radiology department visit as it decreases pre-exam anxiety and increases overall patient respect for the radiology profession, without having to meet a radiologist in person.


Falls are a major health burden for older adults with Parkinson’s disease (PD), but there is currently no reliable questionnaire to capture the circumstances and consequences of falls in older adults with PD. This study aimed to develop a PD-specific falls questionnaire and to evaluate its test-retest reliability in older adults with PD.n = 30, paper n = 16), who completed the questionnaire twice, 4 weeks apart. Kappa (κ) statistics were used to establish test-retest reliability of the questionnaire items.A novel PD-specific falls questionnaire (PDF-Q) was developed in two modes (online and paper-based version) and used to assess falls and near-falls events over the past 12-months. Questions were agreed upon by an expert group, with the domains based on previous falls-related questionnaires. The questions included the number and circumstances  of falls and near-falls, and consequences  of falls. The PDF-Q was distributed to 46 older adults with PD (online κ = 0.41) and the number of near-falls (κ = 0.51) in the previous 12-months demonstrated weak agreement, while questions on the location of falls (κ = 0.89) and near-falls (κ = 1.0) demonstrated strong to almost perfect agreement. Questions on the number of indoor (κ = 0.86) and outdoor (κ = 0.75) falls demonstrated moderate to strong agreement, though questions related to the number of indoor (κ = 0.47) and outdoor (κ = 0.56) near-falls demonstrated weak agreement. Moderate to strong agreement scores were observed for the most recent fall and near-fall in terms of the direction , activity  and cause .Pooled results from both questionnaires for all participants were used to assess the overall test-retest reliability of the questionnaire. Questions assessing the number of falls (The new PDF-Q developed in this study was found to be reliable for capturing the circumstances and consequences of recent falls and near-falls in older adults with PD.The online version contains supplementary material available at 10.1186/s12877-021-02555-6. Falls are a major health burden for both healthy –3 and neTo our knowledge, there are no reliable PD-specific falls questionnaires. To date, most of the previous research examining the circumstances and consequences of falls in older adults with PD have utilised either semi-structured interviews or self-report falls diaries –24. WhilIn community-dwelling older adults, questionnaires have been used to assess falls risk factors and falls circumstances –30, inclAlthough most falls-specific questionnaires have traditionally been administered using the pen and paper method, this method has some limitations including the cost to administer and enter the data from such questionnaires, the time taken for participants to respond and potential limitations related to population reach . As a reApproval for this study was granted by the Deakin University Human Research Ethics Committee (HEAG-H 32_2016). The PD falls questionnaire (PDF-Q) was constructed using a step-wise strategy previously used for the development of reliable questionnaires , 43. ThiQuestionnaire domains were developed based on previous studies exploring falls circumstances among geriatric populations , 27, 44,From the studies exploring falls circumstances among geriatric populations , 27, 44,Participants were included in this study if they were medically diagnosed with having PD, taking PD medication, and not receiving deep brain stimulation. Participants were excluded if they had not experienced a fall or near-fall in the previous 12-months. Furthermore, participants were asked to complete the Montreal Cognitive Assessment and a cut-off score < 26 of 30 was used to indicate the presence of mild cognitive impairment, which precluded participation in this study.http://www.SurveyMonkey.com), with instructions on when to complete the test and retest questionnaire. For the paper-based questionnaire, 36 older adults with PD were contacted who had previously participated in a research project ). In this regard, the proxy respondents were instructed to list the falls responses based on the information provided directly by the participant only and were required to do the same at retest.This study implemented a two-part recruitment process for the online and paper-based questionnaires, which began after pilot testing. To assess test-retest reliability of either the online or paper-based questionnaires, participants were asked to complete the PDF-Q twice, four-weeks apart. A four-week washout period is recommended as an acceptable time period to avoid memory response bias . The tim project  conducte“do not remember”, or unanswered questions, were subsequently coded as missing. The following standards were used to interpret the level of agreement for the κ coefficient between items: 0–0.20 = None, 0.21–0.39 = Minimal, 0.40–0.59 = Weak, 0.60–0.79 = Moderate, 0.80–0.90 = Strong, > 0.90 = Almost Perfect [Statistical analysis was conducted using Stata/SE 15 . Independent t-test for continuous variables and chi-square tests for categorical variables were used to compare demographic, physical and disease status characteristics between participants that completed the paper and online version of the questionnaire. Test-retest reliability for the PDF-Q was assessed by comparing the agreement between the first and second administered questionnaires for the online and paper-based questionnaire separately and both combined. Levels of agreement were determined using the Kappa (κ) statistic (with standard error) for each fall and near-fall individual questions within the PDF-Q. For ordinal response variables, weighted κ was calculated using the default weighting matrix provided in Stata/SE 15. To provide an estimate of the reliability of each domain, the individual κ scores from each question within each domain were averaged to provide an overall κ score of the domain. The first 10 questions of the PDF-Q consisted of standard physical characteristic and disease-specific items, which did not relate specifically to falls or near-falls and were therefore excluded from the test-retest examination to eliminate a false test-retest reliability outcome. All participants were instructed to respond to all questions. However, for the test-retest analysis, any responses of  Perfect .n = 46) responses (combined online and paper-based questionnaire data). However, for transparency and descriptive purposes, we have reported the findings from each questionnaire separately.Previous research suggests that sample sizes of at least 25 participants for test-retest reliability experiments are needed to meet the confidence interval bound ratio requirements . It has Characteristics of participants completing the paper and online versions of the questionnaire and all participants combined are reported in Table n = 16), the focus of the results is on the test-retest reliability outcomes of the pooled responses from both questionnaires combined (n = 46). However, for the majority of the individual questions, there was comparable test-retest reliability for the online and paper-based questionnaire. Furthermore, only data for the participants’ two most recent falls and near-falls were included as most participants either could not remember the details of the events beyond the two most recent falls and near-falls  or did not have more than two falls or near-falls .Descriptive statistics and test-retest agreement for each question of the PDF-Q are provided for falls Table , near-faκ = 0.41), but the questions concerning the location of falls (κ = 0.89) and the number of indoor (κ = 0.86) and outdoor (κ = 0.75) falls all demonstrated moderate to strong agreement. For the most recent indoor and outdoor fall, there was moderate to strong agreement for the questions related to the location , direction , activity , and cause . Similar results were observed for the second most recent indoor and outdoor fall questions regarding the circumstances   domain based on the pooled questionnaire results was 0.79, which represented moderate agreement. As shown in Table κ = 0.51), while questions concerning the location of near-falls demonstrated almost perfect agreement (κ = 1.0) (Table κ = 0.47) and outdoor (κ = 0.56) near-falls, while the direction , activity  cause  of near-falls questions all demonstrated between weak to moderate agreement  domain for the pooled questionnaire results was 0.60, which represented moderate agreement. Questions assessing the number of near-falls in the previous 12-months demonstrated weak agreement (0) Table . In contnt Table . Once mont Table .κ = 0.90), the number of injurious falls (indoor κ = 0.59), number of visits to a healthcare professional (indoor κ = 0.65), injuries sustained as a result of an injurious fall  and medical treatment sought for any injurious fall (κ = 0.89). Due to only one person in this cohort experiencing a fracture, the κ values were not provided for fracture-related questions. Similarly, only one person reported experiencing an injurious outdoor fall, and so the κ values for these questions were also not provided.The overall average κ score for the injurious falls domain based on the pooled questionnaire results was 0.73, which represented moderate agreement. As shown in Table To our knowledge, the PDF-Q used in this study is the first falls-specific questionnaire to be developed and tested for reliability among older adults with PD. The main finding from this study was that the pooled results from the online and paper modes for the PDF-Q collectively demonstrated moderate to strong agreement (reliability) scores for most questions related to the circumstances and consequences of falls and near-falls, though there was a weaker agreement for the number of falls and near-falls questions. These findings indicate that the PDF-Q represents a reliable tool to capture the circumstances and consequences of falls and near-falls in older adults with PD, yet the recall length (previous 12-months) may be too long to accurately remember the number of falls and near-falls sustained.Since there is no previous data on the reliability of PD-specific falls-related questionnaires, it is difficult to make direct comparisons with our test-retest results. In non-PD older adults, there is data on the test-retest reliabilities of both the Carefall Triage Instrument  and the κ = 0.60) demonstrated relatively weaker reliability than the circumstances of the falls domain (κ = 0.79), although both domains still demonstrated moderate reliability. Firstly, near-fall events may be a less traumatic experience compared to an actual fall, particularly if the individual experiences an injury as a result of the fall [n = 21, κ = 0.89). Thus, it may be that older adults with PD are more likely to recall the circumstances of events preceding a fall resulting in injury, compared to near-falls where injuries are less likely. Jayasinghe et al., [“any incident where you may have fallen but were able to catch yourself and did not come to rest on the ground”. Although this definition may be open to interpretation, we were still able to demonstrate mostly moderate levels of agreement for each question within the near-falls domain. As such, despite the relatively weaker reliability scores compared to the circumstances of the falls domain, we believe that the PDF-Q represents a reliable tool to capture near-falls information in older adults with PD.As a comparison between the pooled PDF-Q domains for falls and near-falls, there are some potential explanations for why the near-falls circumstances domain  to reduce memory bias and improve the precision of the responses , 50. As n > 25) of individuals with PD who have suffered an injurious fall(s) to strengthen these findings.The pooled results for the injurious falls domain demonstrated moderate to strong agreement for each question within the PDF-Q. To our knowledge, no studies have reported test-retest reliability for injurious falls among older adults with PD. In this study, data from 15 participants were used for the test-retest analysis on the number and circumstances of injurious falls in the past 12-months. As such, the reliability results for the injurious falls questions must be interpreted with caution, as it has been reported that at least 25 participants are required for acceptable test-retest reliability analysis . Neverthn = 16) we were unable to directly compare the test-retest reliability findings with the online version. Nevertheless, it is worth noting that for many of the individual questions there was a similar level of agreement (reliability) between the online and paper-based version. Consistent with this observation, several previous studies have shown comparable responses (and similar reliabilities) between paper and online questionnaires among healthy populations [most recent’ fall/near-fall event following the four-week washout period. However, we postulate that given the acceptable levels of agreement scores for the majority of questions, many of the most recent falls/near-falls remained the same even after 4 weeks. Third, we acknowledge that with the falls and near-falls domains some descriptive questions presented lower agreement scores compared to others, which may have been the result of inadequate instruction; particularly concerning the order of the most recent events. However, given the high number of “don’t remember” responses from participants for falls/near-falls 3 and 4 compared to falls/near-falls 1 and 2, we suspect that participants interpreted fall/near-fall 1 as being their most recent event and fall/near-fall 2 as their second most recent, and so on. Indeed, it may be that older adults with PD find it difficult to recall falls/near-falls events beyond the two most recent events [A strength of this study was the step-wise development of the PDF-Q, which included a literature search and expert consensus regarding the questions and domains of the instrument. However, there are several limitations associated with this study that must be acknowledged. Firstly, we experienced difficulties in recruiting older adults with PD to complete the paper-based version of the PDF-Q, and due to this small sample size (ulations , 60–62. ulations . Second,ulations , 64, it t events , 53. ResIn conclusion, the new PDF-Q developed in this study was found to be reliable for capturing the circumstances and consequences of recent falls and near-falls in older adults with PD, but showed weaker agreement for the questions concerning the number of falls and near-falls in the previous 12-months. It is possible that the recall period was too long for participants to accurately remember the number of falls and near-falls events experienced, though more research is needed to investigate the reliability of these questions using shorter recall lengths to confirm this. There was also a comparatively weaker agreement between the near-falls circumstances domain and the circumstances of the falls domain of this questionnaire. This is possibly due to older adults with PD being less able to precisely recall the events surrounding near-falls, which are generally less traumatic compared to falls. However, further exploration is needed comparing the precision of recalling the events surrounding near-falls to falls among older adults with PD to verify our contention. The step-wise design of the PDF-Q was sufficient in establishing content validity of the instrument. Despite this, future studies should aim to establish criterion and construct validities of the PDF-Q. Overall, this is the first attempt of any kind to develop and demonstrate test-retest reliability of a PD-specific falls questionnaire, which will serve as a valuable tool for accurately capturing falls, near-falls and injurious falls information from older adults with PD.Additional file 1.


Elderly population is more likely to suffer from malnutrition due to aging-associated factors that influence nutritional status like loss of appetite, swallowing difficulties, digestive problems, and chronic illness. There is insufficient information related to the nutritional status of the elderly in Nepal. Hence, this study aims to determine the prevalence of malnutrition among elderly people living in the rural area of the Kavrepalanchok district.A descriptive cross-sectional study was conducted among 320 elderly people aged ≥60 years in a rural area of Kavre district from August to October 2019. Ethical approval was taken from the Institutional Review Committee (IRC-KUSMS: 68/19). Convenient sampling was done. Data analysis was performed using the Statistical Program for Social Sciences version 23.2 (Mean ± SD).The prevalence of malnutrition was higher among females 19 (15%) compared to males 18 (9.3%).The prevalence of malnutrition and risk of malnutrition was 37 (11.6%) and 159 (49.7%), respectively. Of 320 elderly persons, 193 (60.3%) males and 127 (39.7%) females, with a mean age of 68.23±7.38 years, participated in this study. The mean BMI was 22.54±3.25 kg/mThe prevalence of malnutrition and risk of malnutrition is high in the study population. Interventions to improve the nutritional status of the elderly should focus primarily on older people, females, and those who have co-morbidities. Ethical approval was taken from the Institutional Review Committee (IRC) of Kathmandu University School of Medical Sciences (Ref No.: 68/19). Informed consent was read and explained to the participants and verbal consent was obtained. The study was conducted from August to October 2019.The study population comprised elderly people aged 60 years and above and holding permanent resident status at the time of the study, defined as at least one year of residence. Individuals unable to respond due to serious physical or mental illness were excluded from the study.Sample size was calculated as,Where,n = sample sizeZ = 1.96 at 95% Confidence Interval (CI)16p = prevalence of elderly malnutrition i.e. 24%q = 1-pe = margin of error, 5%Considering a 15% non-response rate, the sample size estimated for the study was 322. The convenience sampling method was used to select the household. Only one eligible participant was selected from each household. If there were more than one eligible participant in a household, we selected one participant using a simple random sampling technique following the lottery method.16 Tool comprises eighteen questions and has four sections: anthropometric measurement, global health and social assessment, dietary assessment, and subjective assessment of health and nutrition. According to the score obtained using the MNA tool, nutritional status was categorized as score ≥ 24 are having normal nutrition, 17 - 23.5 “at risk” of malnutrition, <17 malnourished.17A pre-designed structured interview schedule was used for additional data collection regarding socio-demographic and lifestyle variables including age, sex, ethnicity, religion, educational status, marital status, smoking status, alcohol consumption and type of family.The nutritional status was assessed using the translated and well-validated Nepali version of the Mini Nutritional Assessment tool specifically designed for elderly people.In four anthropometric assessments, height was measured with a portable standard stature scale, without footwear. The participant stood on a flat surface facing the interviewer with their feet together and heels against the backboard with knees straight. Height was recorded in centimeters. Weight was measured with a portable digital weighing scale. The instrument was placed on a firm, flat surface. Weight was measured with minimum clothes and no footwear. Weight was recorded in kilograms. Body Mass Index (BMI) was calculated using formula weight in kilograms divided by the square of the height in meters. Mid Upper Arm Circumference (MUAC), and calf circumference were measured to the nearest 0.1 cm using a non-stretchable measuring tape.19Participants were categorized into three ethnic groups, namely: Upper Caste, Janjatis and Dalit. These three ethnic groups generally represented higher, medium, and lower social status, with the Dalit representing the most marginalized of all groups.16 According to smoking habits, participants were categorized as never smoker, current smoker (smoking for at least a year), and former smoker (quit over one year ago). Alcohol consumption was defined as: never, infrequent (consumed once in a month), frequent (who consumed once or more in a week).20Participants were categorized as illiterate, informal, and literate according to their educational status. Informal education referred to having some literacy skills but no formal education.Data analysis was performed using the Statistical Program for Social Sciences (SPSS) version 23. Sample characteristics were described using mean and standard deviation for continuous variable and percentage for a categorical variable.A total of 320 individuals participated in the study  and females: 127 (39.7%)). Socio-demographic characteristics of the study population are provided .The ages of the participants ranged from 60 to 98 years, with a mean age of 68.23±7.38 years (Mean±SD). A majority of 193 (60.3%) of the elderly was in the age group of 60-69. A majority of the participants, 213 (66.6%) belonged to the upper caste category, were Hindu 276 (86.3%) by religion and were illiterate 216 (67.5%). Most of the study subjects, 248 (77.5%) were married. A total of 97 (30.3%) participants were current smokers and 90 (28.1%) reported to have ever consumed alcohol. The mean BMI of the study participants was 22.54±3.25 (Mean±SD). The prevalence of normal nutrition, risk of malnutrition and malnutrition was 38.7%, 49.7% and 11.6%, respectively.The nutritional status of the respondents as per the MNA scores. Total 124 (38.7%) had normal nutritional status, 159 (49.7%) were at risk of malnutrition, while 37 (11.6%) of the respondents were malnourished with MNA scores less than 17 points .21 findings from Rajasthan were 11.6%  and 46% ,22 studies from Tamilnadu reported 14% malnourished and 49% at risk of malnutrition,23 Aliabadi M et al. in their study in Iran reported 12% malnourished and 45.3% at risk of malnutrition.24 Our findings are comparable to all of the above-mentioned studies that used MNA as a tool for assessing nutritional status. Compared to our findings, Ghimire et al.16 and Tamang et al.,25 in their study among Nepal's rural population, reported a higher prevalence of malnutrition . Similarly, studies conducted in Manipur, West Bengal, Karnataka, and Bangladesh also found a higher prevalence of malnutrition .28 There are studies conducted in Pakistan,29 India30 and Hong Kong31 which found a much lower prevalence of malnutrition  than our study. This discrepancy may be due to differences in the socioeconomic conditions of the study population.In this study, we assessed the nutritional status of the elderly population aged 60 years and above using Mini Nutritional Assessment (MNA) Questionnaire. The current study in rural Nepal on 320 elderly participants showed that 11.6% of the elderly were malnourished and about 49.7% of the elderly were at risk of malnutrition. A study from Kerala reported 11.6% were malnourished and 46.5% at risk of malnutrition,35 This observation could be because, with the aging, cumulative effect of many factors like physical inactivity, loss of appetite, presence of other diseases, and adverse economic conditions can contribute to malnutrition in elderly people.In our study, we found that the prevalence of malnutrition increased with the increase in age. Similar findings have been reported in the previous studies.36 In contrast to our finding, Ramya MS et al. in their study reported that the prevalence of malnutrition was more in males.34 Higher prevalence of malnutrition in our findings could be because of the cultural practices in Nepal. According to the tradition, women are the ones to eat last after feeding men and children with nutritious food. At times women may be left with little food and which may be less nutritious. However, we think more detailed studies should be carried out to gather more evidence to support this finding.Consistent with our finding, several studies from different parts of the world have found a high prevalence of malnutrition in elderly females than males.16 Bangladesh,28 Pakistan29 and Iran.37Our findings that the prevalence of malnutrition was high among participants who reported to have comorbidities are consistent with the results of earlier studies conducted in Nepal,There were certain limitations of the study; however, this being a cross-sectional study establishing a causal relationship was not possible. The study's findings cannot be generalized as it covered only a sample of individuals from one community.Based on our findings, we can conclude that prevalence of malnutrition and at risk of malnutrition in the study, the population is 11.6% and 49.7%, respectively. Our study found that the prevalence of malnutrition was high among the older age group, female gender and participants with co-morbidities. Interventions to improve the nutritional status of the elderly should focus primarily on older people, the female gender and those who have co-morbidities.


Near-death experiences receive mention in VRE, because near-deathfulfils James’ criteria for a spiritual experience whereby ‘feelings,acts and experiences’ touch ‘whatever they may consider thedivine’. For James mystical experiences eclipse the influence of near-death. However, sinceRaymond Moody’s ‘Life after Life’ in 1975, near-deathexperiences have gained wide attention, forging a deeply imbedded image of whatspiritual experience means to many people today. The drama of going through a tunnel,being enveloped by ‘the light’, hovering above one’s body duringcrisis and meeting deceased loved ones or spiritual beings constitutes a powerfulnarrative repeatedly portrayed in popular media. Broad interest in near-death could alsobe fuelled by the likelihood of its common occurrence. Syncope in a safe laboratoryenvironment provokes the core experiences of near-death,Understanding brain mechanisms during spiritual experience has obviously advanced sharplysince James’ time. Mystical experience currently enjoys a scientific and medicalrenaissance aided by recognizing the role of serotonergic 2a receptor agonists.Furthermore, accumulating evidence supports the notion that rapid eye movement (REM)consciousness intruding into wakefulness contributes essential elements to near-deathexperience. Such insights allow a fuller exploration of these sublime experiences.In this issue, Peinkhofer and colleaguesTheir first line of evidence stems from the array of creatures showing immobility withthreat. From insect to humankind, thanatosis represents convergent evolution given thediversity of nervous systems sub-serving the phenomena across phyla. Ascribing biologicpurpose invites anthropomorphic bias, a caution acknowledged by the authors, for atoniaand stillness bolster many survival strategies. The immobility of insects can representthreat assessment. Stillness also supports camouflage and not feigning death. Rabbitsfreeze, immobile but not atonic, to improve the odds of being undetected by predators.In rats, freezing signals danger to others. Prey movement triggers predator attacks,such as the North American cougar, prompting wildlife experts to advise against runningwhen humans confront the cat. Felines carry their young to safety by lifting them by thescruff of their necks reflexively inducing atonia.The investigators examined near-death experiences during encounters with‘modern’ predators. This analysis is notable because the content ofnear-death is shaped by immediate surroundings and events as well as prior lifeexperiences. The number of subjects with near-death provoked by ‘modern’predators represents a clear minority of their cases. This finding seems counter totheir argument, until considering how the contemporary causes of near-death are tied topredation. Many studies report the most frequent proximate cause of near-death involvesa threat to cerebral blood flow (syncope or cardiac arrest), conditions readilyenvisioned arising from struggles with predators. Furthermore, simply believing onefaces death is sufficient for experiences nearly indistinguishable from near-death inlife-threatening circumstances.,The principal strength of the hypothesis ties the evolutionary value of stillness toproposed mechanisms of near-death experience. In particular, REM intrusion of whichatonia, useful for feigning death, constitutes a major feature. Other features of REMintruding into wakefulness include hallucinations and autoscopy. Individualsexperiencing near-death have arousal systems predisposed to REM intrusion.REM mechanisms have a long-recognized association with cardiopulmonary function.Stimulating cardiopulmonary afferents rapidly, ‘reflexively’ triggersREM in animalsA component of the pontine REM flip-flop switch is the ventrolateral portion of theperiaqueductal grey (vlPAG). The vlPAG favours waking consciousness, functioning as aREM-off component suppressing REM. The vlPAG reacts vigorously to physiologic crisis.Pain, hypoxia and moderate blood loss stimulate the vlPAG, promoting wakefulness. Yetthe vlPAG response changes when systemic blood flow becomes profoundly low. Withmoderate blood loss, the vlPAG supports the adrenergic system to maintain bloodpressure. Paradoxically, with marked blood loss, vlPAG neurons diminish the peripheraladrenergic cardiovascular tone, bringing the cholinergic system to dominance,Atonia in the setting of severe hypotension could aid prey to lie quietly hidden withoutthrashing or issuing cries of distress, behaviour irrelevant to feigning death.Alternatively, although submission to predators following severe injury isdisadvantageous to the individual, this trait could be advantageous to the species bycurtailing attack upon on others. Sacrificing one for the many contains evolutionaryvalue. Behaviour resulting from atonia can foster more than a single evolutionaryadvantage, with thanatosis as one. Syncopal atonia with physical collapse improvingvenous return to the heart, as another.The investigators point out that thanatosis may share characteristics of laughter fromtickling as a preserved behaviour with no clearly defined biologic purpose. Laughter isa well-recognized precipitant of cataplexy in orexin deficient narcolepsy, a disorderclinically defined by pathologic REM intrusion. Laughter suppresses motor neurons,possibly sharing the physiology of REM cataplexy.Those motionless moments evoked by REM mechanisms may be one form of stillness leading toexperiences presently regarded as near-death. Some find this thought unsettling,especially when reducing these experiences to vestigial consequences of primal biology.Here James offers counsel to persons whose near-death experience steadfastly transformedpersonal meaning and spirituality: ‘by their fruit ye shall know them, not bytheir roots’.