An Exploration of the Optimal Feature-Classifier Combinations for Transradial Prosthesis Control.

Within state-of-the-art gesture-based upper-limb myoelectric prosthesis control, gesture recognition commonly relies on the classification of features extracted from electromyographic (EMG) data gathered from the amputee's residual forearm musculature. Despite best efforts in broadly maximizing gesture recognition accuracy, there does not yet exist a feature-classifier combination accepted as best-practice. In turn, this work hypothesizes that no single feature-classifier combination can consistently maximize accuracy across subjects, positing instead that control schemes should be personalized to the individual. To investigate this hypothesis, the study employed the 40-subject, 49-gesture Ninapro Database 2 (DB2) to compare the performance of 7 different historic, more recent, and state-of-the-art feature sets when classified by 5 machine learning algorithms commonly seen within EMG-based pattern recognition literature. The results demonstrate the ability of Linear Discriminant Analysis (LDA) to marginally exceed other more computationally intensive classifiers in terms of mean accuracy, while the feature set which maximized the highest proportion of individuals' accuracies was shown to vary with both classifier choice and gesture count.

Situational analysis of 10 countries with a high burden of drug-resistant tuberculosis 2 years post-UNHLM declaration: progress and setbacks in a changing landscape.

OBJECTIVES: Globally, drug-resistant tuberculosis (DR-TB) is the leading cause of death globally related to antimicrobial resistance, affecting 500,000 emergent cases annually. In 2018, the first United Nations High-Level Meeting (UNHLM) on tuberculosis declared DR-TB a global public health priority. Bold country targets were established for 2018-2022. This study reviews the DR-TB situation in 2018, and the UNHLM target accomplishments in 10 high-burden countries (HBCs). METHODS: An ecological descriptive analysis of the top 10 DR-TB HBCs (Bangladesh, China, India, Indonesia, Myanmar, Nigeria, Pakistan, Philippines, Russian Federation, and South Africa), which share 70% of the global DR-TB burden, was undertaken, complemented by a cascade-of-care analysis and a survey gathering additional information on key advances and setbacks 2 years after the UNHLM declaration. RESULTS: Most countries are showing historic advances and are on track for the 2018 and 2019 targets. However, according to the cascade-of-care, none of the countries are capable of providing effective care for 50% of the estimated patients. Increasing levels of fluoroquinolone resistance and access to timely susceptibility testing can jeopardize ongoing adoption of shorter, all-oral treatment regimens. The programmatic management of DR-TB in children remains minimal. Achievements for 2020 and beyond may be affected significantly by the coronavirus disease 2019 (COVID-19) pandemic. CONCLUSION: Triggered by the COVID-19 pandemic, there is a global risk of recoil in DR-TB care with long-term consequences in terms of deaths, suffering and wider transmission. Investment to support DR-TB services is more important now than ever to meet the aspirations of the UNHLM declaration.

A multi-site validation in India of the line probe assay for the rapid diagnosis of multi-drug resistant tuberculosis directly from sputum specimens.

UNLABELLED: Rifampicin (R) and isoniazid (H) are key first-line anti-tuberculosis drugs. Failure to detect resistance to these two drugs early results in treatment failure and poor clinical outcomes. The study purpose was to validate the use of the GenoType MTBDRplus line probe assay (LPA) to detect resistance to R and H in Mycobacterium tuberculosis strains directly from smear-positive sputum samples in India. METHOD: Smear positive sputum specimens from 320 patients were subjected to LPA and results compared against those from conventional Lowenstein Jensen (LJ) culture and drug susceptibility testing (C&DST). All specimens with discordant R DST results were subjected to either sequencing of the rpoB gene and/or repeat DST on liquid culture (MGIT 960) at a National Reference Laboratory. RESULTS: Significantly higher proportion of interpretable results were observed with LPA compared to LJ C&DST (94% vs. 80%, p-value <0.01). A total of 248 patients had both LJ and LPA DST results available; 232 (93.5%) had concordant R DST results. Among the 16 discordant R DST results, 13 (81%) were resolved in agreement with LPA results. Final LPA performance characteristics were sensitivity 96% (CI: 90%-98%), specificity 99% (CI: 95%-99%), positive predictive value 99% (CI: 95%-99%), and negative predictive value 95% (CI: 89%-98%). The median turnaround testing time, including specimen transportation time, on LPA was 11 days as compared with 89 days for LJ C&DST. CONCLUSIONS: LPA proved highly accurate in the rapid detection of R resistance. The reduction in time to diagnosis may potentially enable earlier commencement of the appropriate drug therapy, leading to some reduction of transmission of drug-resistant strains.

Formation of octapod MnO nanoparticles with enhanced magnetic properties through kinetically-controlled thermal decomposition of polynuclear manganese complexes.

Polynuclear manganese complexes are used as precursors for the synthesis of manganese oxide nanoparticles (MnO NPs). Altering the thermal decomposition conditions can shift the nanoparticle product from spherical, thermodynamically-driven NPs to unusual, kinetically-controlled octapod structures. The resulting increased surface area profoundly alters the NP's surface-dependent magnetism and may have applications in nanomedicine.

Cubic assembly of a geometrically frustrated {Fe12} spin cluster.

We describe an S(4)-symmetric {Fe(12)} spin cluster [Fe(12)O(4)(OH)(2)(L)(4)(OAc)(8)][Cl](2) {H(4)L = (HOCH(2)CH(2))(2)NCH(2)CH(2)N(CH(2)CH(2)OH)(2)} where the iron(III) centres describe a squashed hexagonal antiprism. The clusters pack into a large cubic cell with circular cavities, lined by weak C-H···O interactions, and a unit cell volume of over 60,000 Å(3) containing large solvent accessible voids. The core of the cluster is stable in solution, as confirmed by electrospray mass spectrometry. The cluster possesses a non-trivial, frustrated S = 0 ground state, due to the presence of multiple competing antiferromagnetic interactions. The finite temperature Lanczos method has been employed to calculate the temperature dependent magnetic properties of an analogous dodecanuclear S(i) = 3/2 model spin system, in order to reduce the very large Hilbert space. Three archetypal models with two independent exchange coupling parameters have been employed that render a low temperature feature possible, as seen in the χ vs. T plot for the {Fe(12)} spin cluster.

Access to an unusual Fe9 core topology from the initial use of tricine in iron(III) cluster chemistry.

We describe an enneanuclear Fe(III) complex with an unusual boat-shaped core topology and an S=11/2 ground state, assembled using the ligands tricine {N-(2-hydroxy-1,1-bis(hydroxymethyl)ethyl)glycine, H(4)L} and 2-phenoxybenzoate.