Food insecurity of smallholder farming systems in B72A catchment in the Olifants River Basin, South Africa

Traditional smallholder farming systems are characterized by low yields and high risks of crop failure and food insecurity. Through a biophysical model, PARCHED-THIRST and a socio-economic farming systems simulation model, OLYMPE, we evaluated the performance of farming practices based on maize yield, gross margin and total family balance over a 10-year period in semi-arid Olifants River Basin of South Africa. Farm profitability under scenarios of different maize productions, maize grain and fertiliser price variations were explored for the identified farming systems. Farm types (A to E) were identified from farm surveys, and validated with farmers and extension officers. The order of vulnerability to severe droughts and food insecurity, starting with the most vulnerable is farm Type B, C, D, A and E. Severe drought or flood shock resulted in highest farm gross margin and total family balance reductions, partly due to loss of production for family consumption. Labour returns ranged from US$62/capita.year for crop-based farm types to US$ 363/capita.year for livestock-based farm Type E. Results revealed that livestock and crop diversification are most proficient strategies to ensure stable income and food security for smallholder farmers. Thus, smallholder farming technology innovations and policies should engage in solutions to poor yields and livestock farming

Nonlinear magneto-optical rotation of frequency-modulated light resonant with a low-J transition

A low-light-power theory of nonlinear magneto-optical rotation of frequency-modulated light resonant with a J=1->J'=0 transition is presented. The theory is developed for a Doppler-free transition, and then modified to account for Doppler broadening and velocity mixing due to collisions. The results of the theory are shown to be in qualitative agreement with experimental data obtained for the rubidium D1 line.Comment: 11 pages, 5 figures, v.2 edited for clarit

Polymeric carriers for amphotericin B: in vitro activity, toxicity and therapeutic efficacy against systemic candidiasis in neutropenic mice

Objective: To study the toxicity and activity of two new amphotericin B formulations: poly(ε-caprolactone) nanospheres coated with poloxamer 188 (AmB-NP) and mixed micelles with the same surfactant (AmB-MM). Materials and methods: The toxicity of these formulations was evaluated in erythrocytes, J774.2 macrophages and LLCPK1 renal cells, as well as in mice. Activity was determined in clinical isolates and in neutropenic mice. Mice were made neutropenic with 5-fluorouracil, infected with Candida albicans and treated with the antifungal formulations for three consecutive days. AmB association in cells and accumulation in kidneys and liver of animals was quantified by HPLC. Results: Both formulations decreased between 8- and 10-fold the MIC of the polyene against clinical isolates of C. albicans. However, their activity was lower than or equal to that of AmB-deoxycholate when it was assessed against C. albicans-infected macrophages. When given as a single intravenous dose in mice, AmB-MM and AmB-NP had an LD50 of 9.8 and 18.6 mg/kg, respectively, compared with 4 mg/kg for AmBdeoxycholate. Comparison of residual infection burdens in the liver and kidneys showed that AmB-deoxycholate (0.5 mg/kg) was more effective and faster in eradicating yeast cells than polymeric formulations. This fact can be related to a lower AmB accumulation inside macrophages and in liver and kidneys (about 1.5 mg drug/g tissue) of mice, compared with those detected for AmB-deoxycholate (4 mg drug/g). Overall, the efficacy of these formulations at 2 mg/kg was equal to that of AmB-deoxycholate at 0.5 mg/kg. Conclusions: AmB-MM and AmB-NP decreased the in vivo antifungal activity of AmB, and higher concentrations were therefore necessary to obtain a similar therapeutic effect. However, these higher concentrations were achievable owing to the reduced toxicity of these formulations

From spinal central pattern generators to cortical network: integrated BCI for walking rehabilitation

Success in locomotor rehabilitation programs can be improved with the use of brain-computer interfaces (BCIs). Although a wealth of research has demonstrated that locomotion is largely controlled by spinal mechanisms, the brain is of utmost importance in monitoring locomotor patterns and therefore contains information regarding central pattern generation functioning. In addition, there is also a tight coordination between the upper and lower limbs, which can also be useful in controlling locomotion. The current paper critically investigates different approaches that are applicable to this field: the use of electroencephalogram (EEG), upper limb electromyogram (EMG), or a hybrid of the two neurophysiological signals to control assistive exoskeletons used in locomotion based on programmable central pattern generators (PCPGs) or dynamic recurrent neural networks (DRNNs). Plantar surface tactile stimulation devices combined with virtual reality may provide the sensation of walking while in a supine position for use of training brain signals generated during locomotion. These methods may exploit mechanisms of brain plasticity and assist in the neurorehabilitation of gait in a variety of clinical conditions, including stroke, spinal trauma, multiple sclerosis, and cerebral palsy

Resonant nonlinear magneto-optical effects in atoms

In this article, we review the history, current status, physical mechanisms, experimental methods, and applications of nonlinear magneto-optical effects in atomic vapors. We begin by describing the pioneering work of Macaluso and Corbino over a century ago on linear magneto-optical effects (in which the properties of the medium do not depend on the light power) in the vicinity of atomic resonances, and contrast these effects with various nonlinear magneto-optical phenomena that have been studied both theoretically and experimentally since the late 1960s. In recent years, the field of nonlinear magneto-optics has experienced a revival of interest that has led to a number of developments, including the observation of ultra-narrow (1-Hz) magneto-optical resonances, applications in sensitive magnetometry, nonlinear magneto-optical tomography, and the possibility of a search for parity- and time-reversal-invariance violation in atoms.Comment: 51 pages, 23 figures, to appear in Rev. Mod. Phys. in Oct. 2002, Figure added, typos corrected, text edited for clarit

Advocacy, support and survivorship in prostate cancer

© 2017 The Authors. European Journal of Cancer Care Published by John Wiley & Sons Ltd Across Australia, prostate cancer support groups (PCSG) have emerged to fill a gap in psychosocial care for men and their families. However, an understanding of the triggers and influencers of the PCSG movement is absent. We interviewed 21 SG leaders (19 PC survivors, two partners), of whom six also attended a focus group, about motivations, experiences, past and future challenges in founding and leading PCSGs. Thematic analysis identified four global themes: illness experience; enacting a supportive response; forming a national collective and challenges. Leaders described men's feelings of isolation and neglect by the health system as the impetus for PCSGs to form and give/receive mutual help. Negotiating health care systems was an early challenge. National affiliation enabled leaders to build a united voice in the health system and establish a group identity and collective voice. Affiliation was supported by a symbiotic relationship with tensions between independence, affiliation and governance. Future challenges were group sustainability and inclusiveness. Study findings describe how a grassroots PCSG movement arose consistent with an embodied health movement perspective. Health care organisations who seek to leverage these community resources need to be cognisant of SG values and purpose if they are to negotiate effective partnerships that maximise mutual benefit

Pure phase-locking of beta/gamma oscillation contributes to the N30 frontal component of somatosensory evoked potentials

BACKGROUND: Evoked potentials have been proposed to result from phase-locking of electroencephalographic (EEG) activities within specific frequency bands. However, the respective contribution of phasic activity and phase resetting of ongoing EEG oscillation remains largely debated. We here applied the EEGlab procedure in order to quantify the contribution of electroencephalographic oscillation in the generation of the frontal N30 component of the somatosensory evoked potentials (SEP) triggered by median nerve electrical stimulation at the wrist. Power spectrum and intertrial coherence analysis were performed on EEG recordings in relation to median nerve stimulation. RESULTS: The frontal N30 component was accompanied by a significant phase-locking of beta/gamma oscillation (25-35 Hz) and to a lesser extent of 80 Hz oscillation. After the selection in each subject of the trials for which the power spectrum amplitude remained unchanged, we found pure phase-locking of beta/gamma oscillation (25-35 Hz) peaking about 30 ms after the stimulation. Transition across trials from uniform to normal phase distribution revealed temporal phase reorganization of ongoing 30 Hz EEG oscillations in relation to stimulation. In a proportion of trials, this phase-locking was accompanied by a spectral power increase peaking in the 30 Hz frequency band. This corresponds to the complex situation of 'phase-locking with enhancement' in which the distinction between the contribution of phasic neural event versus EEG phase resetting is hazardous. CONCLUSION: The identification of a pure phase-locking in a large proportion of the SEP trials reinforces the contribution of the oscillatory model for the physiological correlates of the frontal N30. This may imply that ongoing EEG rhythms, such as beta/gamma oscillation, are involved in somatosensory information processing.Comparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

Within and between-day loading response to ballet choreography

Overuse pathologies are prevalent in ballet injury. Ten amateurballet dancers (age: 23.20 ± 3.08 years) completed a progressive5-stage choreographed routine on two consecutive days. Tri-axialaccelerometers positioned at C7 and the dominant and nondominant lower-limb were used to calculate accumulatedPlayerLoadTM (PLTOTAL) and uni-axial contributions of the anteriorposterior (PLAP), medial-lateral (PLML), and vertical (PLV) planes.PLTOTAL increased significantly (p = 0.001) as a function of exerciseduration within-trial, however there was no significant changebetween trials (p = 0.18). PLTOTAL at C7 was significantly(p = 0.001) lower than both lower-limbs, with no bilateral asymmetry evident (p = 0.97). Planar contributions to PLTOTAL were significantly greater in PLV than PLAP and PLML (p = 0.001). PlayerLoadTMdemonstrated within-trial sensitivity to the progressive routine,however no residual fatigue effect was observed between trials.The results of this study suggest that accelerometers have efficacyin athlete monitoring and injury screening protocols, however unitplacement should be considered for practical interpretation

The relationship of social determinants and distress in newly diagnosed cancer patients

Patients with a new cancer diagnosis can experience distress when diagnosed. There are disparities in treatment of cancer patients based on social determinants, but minimal research exists on the relationship of those social determinants and distress after a new cancer diagnosis. Our goals were to determine the social determinants associated with distress after a new cancer diagnosis and determine the relationship of distress with outcome. Patients with a new cancer diagnosis at one institution from January 2019 to December 2020 were analyzed. Patients were given the National Comprehensive Cancer Network (NCCN) distress thermometer during their first visit. Demographics, tumor characteristics, clinical variables and survival were recorded. Patients were also asked to share specific factors that led to distress, including: (1) financial, (2) transportation, (3) childcare and (4) religious. A total of 916 patients returned distress thermometers. Mean age was 59.1 years. Females comprised 71.3 (653/916) percent of the cohort. On Dunn\u27s multiple comparison, the following factors were associated with increased distress level: female (p \u3c 0.01), ages 27 to 45 (p \u3c 0.01), uninsured (p \u3c 0.01) and unemployed (p \u3c 0.01). Patients with higher distress scores also experienced worse overall survival (p \u3c 0.05). Females, young patients, uninsured patients and unemployed patients experience more distress after a new cancer diagnosis. Increased distress is independently associated with worse overall survival. Social determinants can be used to predict which patients may require focused interventions to reduce distress after a new cancer diagnosis

Do Gravity-Related Sensory Information Enable the Enhancement of Cortical Proprioceptive Inputs When Planning a Step in Microgravity?

International audienceWe recently found that the cortical response to proprioceptive stimulation was greater when participants were planning a step than when they stood still, and that this sensory facilitation was suppressed in microgravity. The aim of the present study was to test whether the absence of gravity-related sensory afferents during movement planning in microgravity prevented the proprioceptive cortical processing to be enhanced. We reestablished a reference frame in microgravity by providing and translating a horizontal support on which the participants were standing and verified whether this procedure restored the proprioceptive facilitation. The slight translation of the base of support (lateral direction), which occurred prior to step initiation, stimulated at least cutaneous and vestibular receptors. The sensitivity to proprioceptive stimulation was assessed by measuring the amplitude of the cortical somatosensory-evoked potential (SEP, over the Cz electrode) following the vibration of the leg muscle. The vibration lasted 1 s and the participants were asked to either initiate a step at the vibration offset or to remain still. We found that the early SEP (90–160 ms) was smaller when the platform was translated than when it remained stationary, revealing the existence of an interference phenomenon (i.e., when proprioceptive stimulation is preceded by the stimulation of different sensory modalities evoked by the platform translation). By contrast, the late SEP (550 ms post proprioceptive stimulation onset) was greater when the translation preceded the vibration compared to a condition without pre-stimulation (i.e., no translation). This suggests that restoring a body reference system which is impaired in microgravity allowed a greater proprioceptive cortical processing. Importantly, however, the late SEP was similarly increased when participants either produced a step or remained still. We propose that the absence of step-induced facilitation of proprioceptive cortical processing results from a decreased weight of proprioception in the absence of balance constraints in microgravity