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Monitoring mosquito host choice to identify high-risk groups for different vector-borne diseases is important to devise vector control strategies and disease management. The present study was conducted to develop and validate a PCR-based method to identify human sex in blood-fed Aedes aegypti mosquitoes. Several human genes present in both the X and Y chromosomes were screened and diagnostic PCR primers were successfully designed and amplified for the human STS gene. The limit of detection of this PCR assay was carried out on Ae. aegypti fed with human blood up to 5 days (120 hours) post blood-meal under laboratory condition. The efficiency of this PCR assay was evaluated in field-collected Ae. aegypti mosquitoes and compared with other existing methods. The developed PCR primers can successfully amplify and distinguish human sex in mosquitoes up to 72 hours after a blood meal, with an amplified product of 627bp and 298bp for male (XY) and 627bp for female (XX) blood-fed mosquitoes. Further, validation of this assay in field-collected Ae. aegypti mosquitoes revealed that this assay could detect human sex in mosquito blood meal substantially more efficiently (c2 = 4.5, p = 0.034) than other PCR based assay. The newly developed PCR assay highly specific to human DNA and can distinguish male and female DNA for up to 72 hours. This assay can be is used for identifying highrisk groups and extended to other medically important hematophagous insects to assess their role in disease transmission and epidemic preparedness.
Sujet(s)
Aedes , Réaction de polymérisation en chaîne , Animaux , Aedes/génétique , Femelle , Mâle , Humains , Réaction de polymérisation en chaîne/méthodes , Comportement alimentaire , Vecteurs moustiques/génétique , SangRÉSUMÉ
Myositis is a clinical condition with a wide spectrum of clinical presentation. We present the case of 33 years old woman with acute history of pain and swelling of both legs. Investigations confirmed acute bilateral myositis of both calf muscles. She responded well to conservative management with full recovery. Benign acute myositis is more common in children and usually follows viral infection. Although our case may represent an adult form of benign acute childhood myositis, she had no history of preceding infections. Benign acute myositis is increasingly reported in adults. It appears to be self-limited with spontaneous full recovery. The diagnosis is largely based on clinical features. Therefore, clinicians should be aware of this type of myositis to avoid unnecessary invasive investigations.
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Stereochemically active lone pair (SCALP) cations are attractive units for realizing optical anisotropy. Antimony(III) chloride perovskites with the SCALP have remained largely unknown to date. We synthesized a new vacancy ordered Cs3Sb2Cl9 perovskite single crystals with SbCl6 octahedral linkage containing the SCALP. Remarkably, all-inorganic halide perovskite Cs3Sb2Cl9 single crystals exhibit an exceptional birefringence of 0.12 ± 0.01 at 550 nm. The SCALP brings a large local structural distortion of the SbCl6 octahedra promoting birefringence optical responses in Cs3Sb2Cl9 single crystals. Theoretical calculations reveal that the considerable hybridization of Sb 5s and 5p with Cl 3p states largely contribute to the SCALP. Furthermore, the change in the Sb-Cl-Sb bond angle creates distortion in the SbCl6 octahedral arrangement in the apical and equatorial directions within the crystal structure incorporating the required anisotropy for the birefringence. This work explores pristine inorganic halide perovskite single crystals as a potential birefringent material with prospects in integrated optical devices.
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Correlated electron materials (CEMs) host a rich variety of condensed matter phases. Vanadium dioxide (VO2) is a prototypical CEM with a temperature-dependent metal-to-insulator (MIT) transition with a concomitant crystal symmetry change. External control of MIT in VO2-especially without inducing structural changes-has been a long-standing challenge. In this work, we design and synthesize modulation-doped VO2-based thin film heterostructures that closely emulate a textbook example of filling control in a correlated electron insulator. Using a combination of charge transport, hard X-ray photoelectron spectroscopy, and structural characterization, we show that the insulating state can be doped to achieve carrier densities greater than 5 × 1021 cm-3 without inducing any measurable structural changes. We find that the MIT temperature (TMIT) continuously decreases with increasing carrier concentration. Remarkably, the insulating state is robust even at doping concentrations as high as ~0.2 e-/vanadium. Finally, our work reveals modulation-doping as a viable method for electronic control of phase transitions in correlated electron oxides with the potential for use in future devices based on electric-field controlled phase transitions.
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Finding stable analogues of three-dimensional (3D) lead halide perovskites has motivated the exploration of an ever-expanding repertoire of two-dimensional (2D) counterparts. However, the bandgap and exciton binding energy in these 2D systems are generally considerably higher than those in 3D analogues due to size and dielectric confinement. Such quantum confinements are most prominently manifested in the extreme 2D realization in (A)mPbI4 (m = 1 or 2) series of compounds with a single inorganic layer repeat unit. Here, we explore a new A-site cation, 4,4'-azopyridine (APD), whose size and hydrogen bonding properties endow the corresponding (APD)PbI4 2D compound with the lowest bandgap and exciton binding energy of all such compounds, 2.19 eV and 48 meV, respectively. (APD)PbI4 presents the first example of the ideal Pb-I-Pb bond angle of 180°, maximizing the valence and conduction bandwidths and minimizing the electron and hole effective masses. These effects coupled with a significant increase in the dielectric constant provide an explanation for the unique bandgap and exciton binding energies in this system. Our theoretical results further reveal that the requirement of optimizing the hydrogen bonding interactions between the organic and the inorganic units provides the driving force for achieving the structural uniqueness and the associated optoelectronic properties in this system. Our preliminary investigations in characterizing photovoltaic solar cells in the presence of APD show encouraging improvements in performances and stability.
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In the world of semiconductors, organic-inorganic hybrid (OIH) halide perovskite is a new paradigm. Recently, a zealous effort has been made to design new lead-free perovskite-like OIH halides, such as perovskitoids and antiperovskites, for optoelectronic applications. In this context, we have synthesized a perovskitoid compound (Piperidinium)MnCl3 (compound 1) crystallizing in an orthorhombic structure with infinite one-dimensional (1D) chains of MnCl6 octahedra. Interestingly, this compound shows switchable dielectric property governed by an order-disorder structural transition. By controlling the stoichiometry of piperidine, we have synthesized an antiperovskite (Piperidinium)3Cl[MnCl4] (compound 2), the inverse analogue of a perovskite, consisting of zero-dimensional (0D) MnCl4 tetrahedra. This type of organic-inorganic hybrid antiperovskite halide is unique and scarce. Such a dissimilarity in lattice dimensionality and Mn2+ ion coordination ensues fascinating photophysical and magnetic properties. Compound 1 exhibits red emission with a photoluminescence quantum yield (PLQY) of â¼28%. On the other hand, the 0D antiperovskite compound 2 displays green emission with a higher PLQY of 54.5%, thanks to the confinement effect. In addition, the dimensionality of the compounds plays a vital role in the exchange interaction. As a result, compound 1 shows an antiferromagnetic ground state, whereas compound 2 is paramagnetic down to 1.8 K. This emerging structure-property relationship in OIH manganese halides will set the platform for designing new perovskites and antiperovskites.
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INTRODUCTION: The coronavirus disease 2019 (COVID-19) pandemic led to hospitals in the UK substituting face-to-face (FtF) clinics with virtual clinic (VC) appointments. We evaluated the use of virtual two-week wait (2-ww) lower gastrointestinal (LGI) clinic appointments, conducted using telephone calls at a district general hospital in England. METHODS: Patients undergoing index outpatient 2-ww LGI clinic assessment between 1 June 2019 and 31 October 2019 (FtF group) and 1 June 2020 and 31 October 2020 (VC group) were identified. Relevant data were obtained using electronic patient records. Compliance with national cancer waiting time targets was assessed. Environmental and financial impact analyses were performed. RESULTS: In total, 1,531 patients were analysed (median age=70, male=852, 55.6%). Of these, 757 (49.4%) were assessed virtually via telephone; the remainder were seen FtF (n=774, 50.6%). Ninety-two (6%, VC=44, FtF=48) patients had malignant pathology and 64 (4.2%) had colorectal cancer (CRC); of these, 46 (71.9%, VC=26, FtF=20) underwent treatment with curative intent. The median waiting times to index appointment, investigation and diagnosis were significantly lower following VC assessment (p<0.001). The cancer detection rates (p=0.749), treatments received (p=0.785) and median time to index treatment for CRC patients (p=0.156) were similar. A significantly higher proportion of patients were seen within two weeks of referral in the VC group (p<0.001). VC appointments saved patients a total of 9,288 miles, 0.7 metric tonnes of CO2 emissions and £7,482.97. Taxpayers saved £80,242.00 from VCs. No formal complaints were received from patients or staff in the VC group. CONCLUSION: Virtual 2-ww LGI clinics were effective, safe and were associated with tangible environmental and financial benefits.
Sujet(s)
COVID-19 , Tumeurs colorectales , Humains , Mâle , Sujet âgé , Orientation vers un spécialiste , COVID-19/épidémiologie , Téléphone , Rendez-vous et plannings , Tumeurs colorectales/diagnostic , Tumeurs colorectales/thérapieRÉSUMÉ
Co-infection of multiple pathogens complicates diagnosis, treatment and preventive measures based on clinical signs. Therefore, reliable diagnostic tool for timely reporting of suspected diseases is very much essential. A novel one-step triplex PCR assay was developed and evaluated for simultaneous detection of three important viruses namely porcine circovirus type 2 (PCV2), porcine parvovirus (PPV) and classical swine fever virus (CSFV) involved in reproductive problems in pigs. Each of the three pairs of oligonucleotide primers exclusively amplified the targeted fragment of the specific viruses. The multiplex PCR assay was found to be sensitive in detecting at least 300 pg of viral genomic DNA or RNA from a mixture of three viruses in a reaction. No amplification was obtained from other common viruses or pathogens, such as porcine reproductive and respiratory syndrome virus (PRRSV), Japanese encephalitis virus (JEV), porcine group A rotavirus (PoRVA), Escherichia coli and Staphylococcus aureus thereby indicating that the developed multiplex PCR has high specificity. Because of the sensitivity and specificity, the developed multiplex PCR assay will be a useful tool for clinical diagnosis of mixed infections of DNA and RNA viruses in pigs.
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Circovirus , Virus de la peste porcine classique , Co-infection , Parvovirus porcin , Maladies des porcs , Virus , Animaux , Circovirus/génétique , Virus de la peste porcine classique/génétique , Co-infection/diagnostic , Co-infection/médecine vétérinaire , Réaction de polymérisation en chaine multiplex , Parvovirus porcin/génétique , Sensibilité et spécificité , Suidae , Maladies des porcs/diagnostic , Virus/génétiqueRÉSUMÉ
Two seemingly similar crystal structures of the low-temperature (â¼100 K) MAPbX3 (X = I, Br, Cl) perovskites, but with different relative methylammonium (MA) ordering, have appeared as representatives of this orthorhombic phase. Distinguishing them by X-ray diffraction experiments is difficult, and conventional first-principles-based molecular dynamics approaches are often too computationally intensive to be feasible. Therefore, to determine the thermodynamically stable structure, we use a recently introduced on-the-fly machine-learning force field method, which reduces the computation time from years to days. The molecules exhibit a large degree of anharmonic motion depending on temperature: that is, rattling, twisting, and tumbling. We observe the crystal's "librational pathways" while slowly heating it in isothermal-isobaric simulations. Marked differences in the thermal evolution of structural parameters allow us to determine the real structure of the system via a comparison with experimentally determined crystal structures.
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Porcine parvovirus (PPV) infection is one of the most important causes of reproductive failure in pigs impacting the piggery industry globally with huge economic losses. A cost-effective, simple, rapid, specific, and sensitive method is critical for monitoring PPV infection on pig farms. The main aim of the present study was to develop and evaluate a loop-mediated isothermal amplification (LAMP) assay for rapid visual detection of porcine parvovirus (PPV) in pigs. A set of six LAMP primers including two outer primers, two inner primers, and two loop primers were designed utilizing the conserved region of capsid protein VP2 gene sequences of PPV and was applied for detection of PPV from porcine samples. Time and temperature conditions for amplification of PPV genes were optimized to be 30 min at 63 °C. The developed assay was ten-fold more sensitive than conventional PCR with analytical sensitivity of 20 pg and 200 pg, respectively. This is the first report of detection of PPV by LAMP assay from India. The assay did not cross-react with porcine circovirus type 2 (PCV2), porcine reproductive and respiratory syndrome virus (PRRSV), or classical swine fever virus (CSFV). The LAMP assay was assembled into a LAMP assay kit of 20 reactions and was validated in different laboratories in India. The newly developed LAMP assay was proved to be a specific, sensitive, rapid, and simple method for visual detection of PPV which does not require even costly equipments for performing the test. It complements and extends previous methods for PPV detection and provides an alternative approach for detection of PPV.
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Techniques de diagnostic moléculaire , Techniques d'amplification d'acides nucléiques , Infections à Parvoviridae , Parvovirus porcin , Maladies des porcs , Animaux , Infections à Parvoviridae/diagnostic , Infections à Parvoviridae/médecine vétérinaire , Parvovirus porcin/génétique , Sensibilité et spécificité , Suidae , Maladies des porcs/diagnosticRÉSUMÉ
It is believed that ferroelectrics may serve as efficient photocatalysts as well as photovoltaic materials but for their large bandgaps which does not allow them to absorb a large part of the solar spectrum. We have explored theoretically within ab-initio density functional theory-based calculations, the efficacy of Cu and Te to co-dope BaTiO3 in reducing its bandgap while retaining its ferroelectric properties. Examining a dopant concentration of 11%, we find an insulating ground state being realized with a band gap reduction of 0.42 eV from the value for undoped BaTiO3 for some doping configurations. Ferroelectric distortions are found to survive even in the presence of doping suggesting possible applications in photocatalysis as well as photovoltaics.
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Suprarenal or adrenal gland haemorrhage is an uncommon but potentially lethal condition if unrecognised. Adrenal masses rarely present with haemorrhage, but they remain an important differential aetiology for adrenal bleeding. We present a novel case of primary adrenal lymphoma with adrenal haemorrhage in a middle-aged woman who presented with right-sided abdominal pain and class 1 haemorrhagic shock. She was found to have spontaneous unilateral adrenal gland haemorrhage in the absence of any underlying previous pathology. Presenting features, diagnosis and subsequent oncological management are reported.
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Tumeurs de la surrénale/imagerie diagnostique , Lymphadénopathie/imagerie diagnostique , Lymphome B diffus à grandes cellules/imagerie diagnostique , Choc hémorragique/diagnostic , Douleur abdominale/étiologie , Maladies des surrénales/imagerie diagnostique , Maladies des surrénales/étiologie , Tumeurs de la surrénale/complications , Tumeurs de la surrénale/traitement médicamenteux , Tumeurs de la surrénale/anatomopathologie , Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Cyclophosphamide/usage thérapeutique , Doxorubicine/usage thérapeutique , Femelle , Hémorragie/imagerie diagnostique , Hémorragie/étiologie , Humains , Lymphome B diffus à grandes cellules/complications , Lymphome B diffus à grandes cellules/traitement médicamenteux , Lymphome B diffus à grandes cellules/anatomopathologie , Adulte d'âge moyen , Prednisone/usage thérapeutique , Rituximab/usage thérapeutique , Choc hémorragique/étiologie , Tomodensitométrie , Échographie , Vincristine/usage thérapeutiqueRÉSUMÉ
Complementary to bulk synthesis, here we propose a designer lattice with extremely high magnetic frustration and demonstrate the possible realization of a quantum spin liquid state from both experiments and theoretical calculations. In an ultrathin (111) CoCr2O4 slice composed of three triangular and one kagome cation planes, the absence of a spin ordering or freezing transition is demonstrated down to 0.03 K, in the presence of strong antiferromagnetic correlations in the energy scale of 30 K between Co and Cr sublattices, leading to the frustration factor of â¼1000. Persisting spin fluctuations are observed at low temperatures via low-energy muon spin relaxation. Our calculations further demonstrate the emergence of highly degenerate magnetic ground states at the 0 K limit, due to the competition among multiply altered exchange interactions. These results collectively indicate the realization of a proximate quantum spin liquid state on the synthetic lattice.
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It is known that the organic units in hybrid halide perovskites are free to rotate, but it is not clear if this freedom is of any relevance to the structure-property relationship of these compounds. We have employed quasi-elastic neutron scattering using two different spectrometers, thus providing a wide dynamic range to investigate the cation dynamics in methylammonium lead bromide (MAPbBr3) and formamidinium lead bromide (FAPbBr3) over a large temperature range covering all known crystallographic phases of these two compounds. Our results establish a plastic crystal-like phase forming above 30 K within the orthorhombic phase of MAPbBr3 related to 3-fold rotations of MA units around the C-N axis with an activation energy, Ea, of â¼27 meV, which has no counterpart in the FA compound. MA exhibits an additional 4-fold orientational motion of the whole molecule via rotation of the C-N axis itself with an Ea of â¼68 meV common for the high-temperature tetragonal and cubic phases. In contrast, the FA compound exhibits only an isotropic orientational motion of the whole FA unit with Ea ≈ 106 meV within the orthorhombic phase and a substantially reduced common Ea of â¼62 meV for the high-temperature tetragonal and cubic phases. Our results suggest that the rotational dynamics of the organic units, crystallographic phases, and physical properties of these compounds are intimately connected.
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We present a combination of thermodynamic and dynamic experimental signatures of a disorder driven dynamic cooperative paramagnet in a 50% site diluted triangular lattice spin-1/2 system: Y_{2}CuTiO_{6}. Magnetic ordering and spin freezing are absent down to 50 mK, far below the Curie-Weiss scale (-θ_{CW}) of â¼134 K. We observe scaling collapses of the magnetic field and temperature dependent magnetic heat capacity and magnetization data, respectively, in conformity with expectations from the random singlet physics. Our experiments establish the suppression of any freezing scale, if at all present, by more than 3 orders of magnitude, opening a plethora of interesting possibilities such as disorder stabilized long range quantum entangled ground states.
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An echocardiographic investigation is one of the key modalities of diagnosis in cardiology. There has been a rising presence of cardiological comorbidities in patients positive for COVID-19. Hence, it is becoming extremely essential to look into the correct safety precautions, healthcare professionals must take while conducting an echo investigation. The decision matrix formulated for conducting an echocardiographic evaluation is based on presence or absence of cardiological comorbidity vis-à-vis positive, suspected or negative for COVID-19. The safety measures have been constructed keeping in mind the current safety precautions by WHO, CDC and MoHFW, India.
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Maladies cardiovasculaires/imagerie diagnostique , Infections à coronavirus/prévention et contrôle , Infection croisée/prévention et contrôle , Échocardiographie/méthodes , Pandémies/prévention et contrôle , Sécurité des patients , Pneumopathie virale/prévention et contrôle , COVID-19 , Cardiologie , Maladies cardiovasculaires/épidémiologie , Infections à coronavirus/épidémiologie , Femelle , Humains , Inde , Prévention des infections/méthodes , Mâle , Pandémies/statistiques et données numériques , Pneumopathie virale/épidémiologie , Guides de bonnes pratiques cliniques comme sujet , Syndrome respiratoire aigu sévère/épidémiologie , Syndrome respiratoire aigu sévère/prévention et contrôle , Sociétés médicalesRÉSUMÉ
Monitoring of anti-malarial drug resistance is vital in Northeast India as this region shares its international border with Southeast Asia. Genetic diversity of Plasmodium parasites regulates transmission dynamics, disease severity and vaccine efficacy. P. falciparum chloroquine resistance transporter (Pfcrt), multidrug resistance-1 (Pfmdr-1) and kelch 13 propeller (PfK-13) genes which govern antimalarial drug resistance and three genetic diversity markers, merozoite surface protein 1 and 2 (Pfmsp-1, Pfmsp-2) and glutamate rich protein (Pfglurp) were evaluated from Tripura, Northeast India using molecular tools. In the Pfcrt gene, 87% isolates showed triple mutations at codons M74I, N75E and K76T. 12.5% isolates in Pfmdr-1 gene showed mutation at N86Y. No polymorphism in PfK-13 propeller was found. Polyclonal infections were observed in 53.85% isolates and more commonly in adults (p = 0.0494). In the Pfmsp-1 locus, the K1 allelic family was predominant (71.2%) followed by the 3D7/IC family (69.2%) in the Pfmsp-2 locus. RII region of Pfglurp exhibited nine alleles with expected heterozygosity of 0.85. The multiplicity of infection for Pfmsp-1, Pfmsp-2 and Pfglurp were 1.56, 1.31 and 1.06 respectively. Overall, the study demonstrated a high level of chloroquine resistance and extensive parasite diversity in the region, necessitating regular surveillance in this population group.
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Antipaludiques/pharmacologie , Résistance aux substances/génétique , Mutation , Plasmodium falciparum/génétique , Chloroquine/pharmacologie , Variation génétique , Inde , Paludisme à Plasmodium falciparum/parasitologie , Plasmodium falciparum/effets des médicaments et des substances chimiquesRÉSUMÉ
A facile route to anchor pseudocapacitive materials on multiwalled carbon nanotubes (CNTs) to realize high-performance electrode materials for asymmetric supercapacitors (ASCs) is reported. The anchoring process is developed after direct decomposition of metal-hexacyanoferrate complex on the CNT surface. Transmission electron microscopy (TEM) analysis reveals that the nanoparticles (NPs) are discretely attached over the CNT surface without forming a uniform layer, thus making most of the entire NP surface available for electrochemical reactions. Accordingly, CNT-Mn3O4 nanocomposite cathode shows significantly improved capacitive performance as compared to pristine CNT electrode, validating the efficacy of designing the composite electrode. With CNT-Fe3O4 nanocomposite as the paired anode, the hybrid ASC delivers a specific capacitance of 135.2 F/g at a scan rate of 10 mV/s within a potential window of 0-1.8 V in the aqueous electrolyte and retains almost 100% of its initial capacitance after 15,000 cycles. The serially connected ASCs can power commercial light-emitting diodes (LEDs) and mobile phones, reflecting their potential in next-generation storage applications.
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Low dimensional lead halide perovskites have attracted huge research interest due to their structural diversity and remarkable photophysical properties. The ability to controllably change dimensionality/structure of perovskites remains highly challenging. Here, we report synthetic control on structure/dimensionality of ethylenediammonium (ED) lead bromide perovskite from a two dimensionally networked (2DN) sheet to a one dimensionally networked (1DN) chain structure. Intercalation of solvent molecules into the perovskite plays a crucial role in directing the final dimensionality/structure. This change in dimensionality reflects strongly in the observed differences in photophysical properties. Upon UV excitation, the 1DN structure emits white light due to easily formed " self-trapped" excitons. 2DN perovskites show band edge blue emission (â¼410 nm). Interestingly, Mn2+ incorporated 2DN perovskites show a highly red-shifted Mn2+ emission peak at â¼670 nm. Such a long wavelength Mn2+ emission peak is unprecedented in the perovskite family. This report highlights the synthetic ability to control the dimensionality/structure of perovskite and consequently its photophysical properties.