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The recent discovery of polar topological structures has opened the door for exciting physics and emergent properties. There is, however, little methodology to engineer stability and ordering in these systems, properties of interest for engineering emergent functionalities. Notably, when the surface area is extended to arbitrary thicknesses, the topological polar texture becomes unstable. Here we show that this instability of the phase is due to electrical coupling between successive layers. We demonstrate that this electrical coupling is indicative of an effective screening length in the dielectric, similar to the conductor–ferroelectric interface. Controlling the electrostatics of the superlattice interfaces, the system can be tuned between a pure topological vortex state and a mixed classical-topological phase. This coupling also enables engineering coherency among the vortices, not only tuning the bulk phase diagram but also enabling the emergence of a 3D lattice of polar textures.

Hierarchical assemblies of ferroelectric nanodomains, so-called super-domains, can exhibit exotic morphologies that lead to distinct behaviours. Controlling these super-domains reliably is critical for realizing states with desired functional properties. Here we reveal the super-switching mechanism by using a biased atomic force microscopy tip, that is, the switching of the in-plane super-domains, of a model ferroelectric Pb0.6Sr0.4TiO3. We demonstrate that the writing process is dominated by a super-domain nucleation and stabilization process. A complex scanning-probe trajectory enables on-demand formation of intricate centre-divergent, centre-convergent and flux-closure polar structures. Correlative piezoresponse force microscopy and optical spectroscopy confirm the topological nature and tunability of the emergent structures. The precise and versatile nanolithography in a ferroic material and the stability of the generated structures, also validated by phase-field modelling, suggests potential for reliable multi-state nanodevice architectures and, thereby, an alternative route for the creation of tunable topological structures for applications in neuromorphic circuits.

Indian Iranis are denotified/nomadic tribes living in India since the sixteenth century. A large migrating group of them was declared criminals under British law. Post-independence too this label continued. Even today, police, media and society treat them as criminals. This article argues that though the British-targeted group of the Indian-Irani community was not involved in crime considerably (28 convictions of petty thefts in 98 years), it was noted as criminal tribes in police reports in and around the Bombay presidency from the year 1842 to 1940. A Police Report on Vagrant Bands of Foreigners of 1879 and notes and books by the then British police officers reflect the same. A then foreign-originated, nontribal, isolated community of Indian Iranis was labelled as criminals by the British colonial administration step-wise. The article briefs that the undue criminalisation of one group from this community further led to the criminalisation of the larger group from this community in independent India. Primary data witnessing the impact of such constant criminalisation on the current generation of the community in Ambivli, Thane district, Maharashtra is also briefly discussed in this article. The theories of labelling in criminology most fit to describe this criminalisation.

The dynamics of complex topological defects in ferroelectric materials is explored using automated experimentation in piezoresponse force microscopy. Specifically, a complex trigger system (i.e., “FerroBot”) is employed to study metastable domain-wall dynamics in Pb0.6Sr0.4TiO3thin films. Several regimes of superdomain wall dynamics have been identified, including smooth domain-wall motion and significant reconfiguration of the domain structures. We have further demonstrated that microscopic mechanisms of the domain-wall dynamics can be identified; i.e., domain-wall bending can be separated from irreversible domain reconfiguration regimes. In conjunction, phase-field modeling was used to corroborate the observed mechanisms. As such, the observed superdomain dynamics can provide a model system for classical ferroelectric dynamics, much like how colloidal crystals provide a model system for atomic and molecular systems.

Social marketing is a proven private sector strategy to provide health-related products, including contraceptives. Pharmacies offer affordable, convenient, and rapid delivery of over-the-counter contraceptives directly to the consumer, providing wider availability and accessibility to family planning (FP) in sub-Saharan Africa. Pilot projects tested the feasibility of including CycleBeads®, the visual tool that supports the use of the Standard Days Method®, into Population Services International (PSI) social marketing programs. The purpose of this article is to review evidence to provide guidance for social marketing CycleBeads in pharmacies in sub-Saharan Africa. Literature on contraceptive provision through pharmacies in comparison to clinics was summarized from developing and developed country contexts, highlighting salient and relevant lessons for the African context in regard to pharmacists’ knowledge and perceptions of FP, clients’ perceptions of pharmacists’ FP knowledge and FP service delivery in pharmacies, and the impact of pharmacy access on contraceptive use. Descriptive data from PSI social marketing initiatives in several African countries, and commercial marketing information were reviewed. Evidence from CycleBeads sales suggests that there is demand for the product and it is affordable in comparison to oral contraceptives. In addition, there were high levels of correct use by women who purchased CycleBeads in pharmacies, suggesting that CycleBeads are an appropriate product for social marketing. Until awareness of and demand for the method increases, social marketing of CycleBeads requires continued subsidy to maintain viability. Training to update pharmacists’ knowledge and increase capacity to provide basic information, positioning of the method, and low profit margins for pharmacies present challenges.

Few community-based data exist on the frequency of cord infection signs in low resource settings, especially in Sub-Saharan Africa. We developed simple sign-based definitions of omphalitis and estimated incidence and risk factors for infection over a range of severity among neonates in Pemba, Zanzibar, Tanzania.

ABSTRACTEscherichia coliO15:K52:H1 is a significant extraintestinal pathogen in Europe (G. Prats et al., J. Clin. Microbiol. 38:201-209, 2000). To search for evidence of this clonal group outside of Europe, 75 non-European E. coliisolates of serogroup O15 were compared with five members of the O15:K52:H1 clonal group from Barcelona, Spain, according to genomic background, virulence genotypes, and antimicrobial resistance profiles. Amplification phylotyping showed that 16 (21%) of the 75 non-European O15 isolates corresponded with the O15:K52:H1 clonal group. The 16 non-European O15:K52:H1 clonal group members represented diverse geographic locales. They were isolated almost exclusively from humans with extraintestinal infections and accounted for 50% of all O15 isolates from five human clinical collections studied. Most non-European clonal group members exhibited a consensus virulence factor profile that included the F16 or F7-2 papAalleles (P fimbrial structural subunit), papGallele II (P fimbrial adhesin), iha(putative adhesin siderophore), and iutA(aerobactin receptor). This resembles the virulence profiles of (i) European representatives of the O15:K52:H1 clonal group and (ii) phylogenetically related “clonal group A,” a recently recognized significant contributor to trimethoprim-sulfamethoxazole resistance in the United States (A. R. Manges et al., N. Engl. J. Med. 345:1007-1013, 2001). Antimicrobial resistance profiles were variable, and resistance was inconsistently transferred by conjugation. These findings indicate that the O15:K52:H1 clonal group is broadly distributed beyond Europe, exhibits previously unrecognized phenotypic and genotypic diversity, and contributes significantly to extraintestinal infections in humans.

Polymorphisms in PapA, the major structural subunit and antigenic determinant of P fimbriae of extraintestinal pathogenic Escherichia coli, are of considerable epidemiological, phylogenetic, and immunotherapeutic importance. However, to date, no method other than DNA sequencing has been generally available for their detection. In the present study, we developed and rigorously validated a novel PCR-based assay for the 11 recognized variants of papA and then used the new assay to assess the prevalence, phylogenetic distribution, and bacteriological associations of the papA alleles among 75 E. coli isolates from patients with urosepsis. In comparison with conventional F serotyping, the assay was extremely sensitive and specific, evidence that papA sequences are highly conserved within each of the traditionally recognized F serotypes despite the diversity observed among F types. In certain strains, the assay detected serologically occult copies of papA, of which some were shown to represent false-negative serological results and others were shown to represent the presence of nonfunctional pap fragments. Among the urosepsis isolates, the assay revealed considerable segregation of papA alleles according to O:K:H serotype, consistent with vertical transmission within clones, but with exceptions which strongly suggested horizontal transfer of papA alleles between lineages. Sequencing of papA from two strains that were papA positive by probe and PCR but F negative in the new PCR assay led to the discovery of two novel papA variants, one of which was actually more prevalent among the urosepsis isolates than were several of the known papA alleles. These findings provide novel insights into the papA alleles of extraintestinal pathogenic E. coli and indicate that the F PCR assay represents a versatile new molecular tool for epidemiological and phylogenetic investigations which should make rapid, specific detection of papA alleles available to any laboratory with PCR capability.

ABSTRACTPolymorphisms in PapA, the major structural subunit and antigenic determinant of P fimbriae of extraintestinal pathogenicEscherichia coli, are of considerable epidemiological, phylogenetic, and immunotherapeutic importance. However, to date, no method other than DNA sequencing has been generally available for their detection. In the present study, we developed and rigorously validated a novel PCR-based assay for the 11 recognized variants ofpapAand then used the new assay to assess the prevalence, phylogenetic distribution, and bacteriological associations of thepapAalleles among 75 E. coliisolates from patients with urosepsis. In comparison with conventional F serotyping, the assay was extremely sensitive and specific, evidence thatpapAsequences are highly conserved within each of the traditionally recognized F serotypes despite the diversity observed among F types. In certain strains, the assay detected serologically occult copies of papA, of which some were shown to represent false-negative serological results and others were shown to represent the presence of nonfunctional papfragments. Among the urosepsis isolates, the assay revealed considerable segregation of papAalleles according to O:K:H serotype, consistent with vertical transmission within clones, but with exceptions which strongly suggested horizontal transfer ofpapAalleles between lineages. Sequencing ofpapAfrom two strains that were papApositive by probe and PCR but F negative in the new PCR assay led to the discovery of two novel papAvariants, one of which was actually more prevalent among the urosepsis isolates than were several of the known papAalleles. These findings provide novel insights into the papAalleles of extraintestinal pathogenic E. coliand indicate that the F PCR assay represents a versatile new molecular tool for epidemiological and phylogenetic investigations which should make rapid, specific detection of papAalleles available to any laboratory with PCR capability.

Tenebrio molitor(mealworms) and Hermetia illucens(Black soldier fly) larvae were analysed for the effect of feed composition on the fatty acid profiles. The larvae were raised on various feeds to which the basal diet had been supplemented to various levels with seed meals (flax seed, chia seed, hemp seed, and rapeseed). Fatty acid classes and composition of both insect larvae were similar in T. molitorand H. illucenslarvae fat; however, the actual percentage composition differed; saturated (28.61% and 86.75%), monounsaturated (MUFA) (52.89% and 7.94%), and polyunsaturated (PUFA) fatty acids (18.49% and 5.31%). The supplementation of the basal diet resulted in larvae fat with increased omega-3 fatty acids levels, and subsequently a lower omega-6 to omega-3 ratio (T. molitor; 4.28:1 in the diet with 10% chia seed, H. illucens; 3.52:1 in the diet with 20% hemp seed) than those of the basal diets (50:1 and 9.91:1 in T. molitorand H. illucensrespectively). In most of the larvae samples, the ratio achieved was closer to that recommended for a healthy diet.

The graphene nanosheets have been deposited on silicon nanowires (SiNWs) at room temperature. SiNWs were grown by hot-wire chemical vapor process (HWCVP). A simple and room temperature approach known as electrophoretic deposition (EPD) process was adopted for the deposition of graphene sheets on SiNWs. GO sheets on SiNWs were converted to reduced graphene oxide (rGO) by photo-reduction method. EPD parameters were optimized to get a uniform coating of rGO on SiNWs. It was observed that the rGO deposition is greatly influenced by the deposition time and the applied voltage in the EPD process. rGO deposition was confirmed by FEG-SEM and FEG-TEM, and the reduction of GO to rGO was verified by Raman, UV–Vis and Fourier transform infrared (FTIR) spectroscopy.