On the rise: Development of a multi-tiered, indoor duckweed cultivation system.

Duckweed species (Lemnaceae) are suitable for remediation and valorization of agri-feed industry wastewaters and therefore can contribute to a more sustainable, circular economy where waste is a resource. Industrial applications will, however, require space efficient cultivation methods that are not affected by prevailing weather conditions. Here, the development and operation of a multi-tiered duckweed bioreactor is described. The developed prototype bioreactor depicted in this paper is composed of four cultivation layers (1 m2 each) with integrated LED lighting (generating up to 150 µmol m-2  s-1 ), a system of pumps and valves to manage the recirculatory flow (2.5 L min-1 ) of wastewater, and an automatic harvesting system. Using a nutrient poor medium, good growth of the duckweed species Lemna minor was achieved in the bioreactor, and this was matched by strong nutrient depletion from the medium, especially for phosphorus (45-mg total phosphorus [TP] removed per m-2  day-1 ). A fully automatic harvesting arm reliably captured similar amounts of duckweed biomass across multiple harvesting cycles, revealing a future scenario whereby labor and interventions by human operators are minimized. Further developments to advance the system towards fully automated operation will include, for example, the use of specific nutrient sensors to monitor and control medium composition. It is envisaged that multi-tiered, indoor bioreactors can be employed in the agri-feed industry where wastewaters are, in many cases, continuously generated throughout the year and need remediating immediately to avoid costly storage. Given the extensive use of automation technology in conventional wastewater treatment plants, multi-tiered duckweed bioreactors can be realistically integrated within the operating environment of such treatment plants. PRACTITIONER POINTS: Duckweed is suitable for remediation and valorization of agri-feed wastewater. Industrial duckweed applications require space efficient cultivation methods. Development and operation of a multi-tiered duckweed bioreactor is detailed. Flow dynamics and automatic harvesting in the bioreactor are optimized. It is concluded that a multi-tiered bioreactor can be used in industry.

Cultivation of Lemna Minor on Industry-Derived, Anaerobically Digested, Dairy Processing Wastewater.

The growth and nutrient uptake capacity of a common duckweed (Lemnaceae) species, Lemna minor "Blarney", on dairy processing wastewater pre-treated by an anaerobic digester (AD-DPW) was explored. L. minor was cultivated in small stationary vessels in a controlled indoor environment, as well as in a semi-outdoor 35 L recirculatory system. The use of AD-DPW as a cultivation medium for L. minor offers a novel approach to dairy wastewater treatment, evolving from the current resource-intensive clean-up of wastewaters to duckweed-based valorisation, simultaneously generating valuable plant biomass and remediating the wastewater.

Flow Rate and Water Depth Alters Biomass Production and Phytoremediation Capacity of Lemna minor.

Given its high biomass production, phytoremediation capacity and suitability as a feedstock for animal and human nutrition, duckweeds are valuable multipurpose plants that can underpin circular economy applications. In recent years, the use of duckweeds to mitigate environmental pollution and valorise wastewaters through the removal of excess nitrogen and phosphate from wastewaters has gained considerable scientific attention. However, quantitative data on optimisation of duckweed performance in phytoremediation systems remain scant. In particular, a mechanistical understanding of how physical flows affect duckweed growth and remediation capacity within vertical indoor multi-tiered bioreactors is unknown. Here, effects of flow rate (0.5, 1.5 or 3.0 L min-1) and medium depth (25 mm or 50 mm) on Lemna minor biomass production and phytoremediation capacity were investigated. Results show that flow rates and water depths significantly affect both parameters. L. minor grew best at 1.5 L min-1 maintained at 50 mm, corresponding to a flow velocity of 0.0012 m s-1. The data are interpreted to mean that flow velocities should be low enough not to physically disturb duckweed but still allow for adequate nutrient mixing. The data presented will considerably advance the optimisation of large-scale indoor (multi-tiered, stacked), as well as outdoor (pond, lagoon, canal), duckweed-based remediation of high nutrient wastewaters.

Outcomes of distal radial endoprostheses for tumour reconstruction: a single centre experience over 15 years.

We report a retrospective study over a 15-year period, between 2005 and 2020, evaluating clinical and functional outcomes in patients who underwent reconstruction of the distal radius with an endoprosthetic replacement following excision of both malignant and aggressive benign bone tumours. Data was collected retrospectively from a prospectively maintained electronic database, and prospectively via telephone patient consultation. Musculoskeletal Tumour Society and patient-rated wrist evaluation scores were assessed at a minimum of 1 year postoperatively. Of nine implants, five were arthrodeses and four were arthroplasties. One patient required amputation within 6 months for proximal metastatic disease. At last follow-up, eight patients subjectively reported good function. Five patients returned to high functionally demanding jobs. Mean Musculoskeletal Tumour Society and patient-rated wrist evaluation scores were 72% and 50/100, respectively. We conclude that distal radius endoprosthetic replacements offer acceptable functional outcomes and remain a viable option when biological reconstruction is not possible.Level of evidence: IV.

Comparison of next generation diagnostic systems (NGDS) for the detection of SARS-CoV-2.

INTRODUCTION: The World Health Organization (WHO) declared coronavirus disease 2019 (COVID-19) a pandemic in March 2020. Initially, supply chain disruptions and increased demand for testing led to shortages of critical laboratory reagents and inadequate testing capacity. Thus, alternative means of biosample collection and testing were essential to overcome these obstacles and reduce viral transmission. This study aimed to 1) compare the sensitivity and specificity of Cepheid GeneXpert® IV and BioFire® FilmArray® 2.0 next generation detection systems to detect SARS-CoV-2, 2) evaluate the performance of both platforms using different biospecimen types, and 3) assess saline as an alternative to viral transport media (VTM) for sample collection. METHODS: A total of 1,080 specimens consisting of nasopharyngeal (NP) swabs in VTM, NP swabs in saline, nasal swabs, oropharyngeal (OP) swabs, and saliva were collected from 216 enrollees. Limit of detection (LoD) assays, NP VTM and NP saline concordance, and saliva testing were performed on the BioFire® FilmArray® 2.0 Respiratory Panel 2.1 and Cepheid GeneXpert® Xpress SARS-CoV-2/Flu/RSV assays. RESULTS: LoD and comparative testing demonstrated increased sensitivity with the Cepheid compared with the BioFire® in detecting SARS-CoV-2 in NP VTM and saline, nasal, and OP swabs. Conversely, saliva testing on the Cepheid showed statistically significant lower sensitivity compared to the BioFire® . Finally, NP swabs in saline showed no significant difference compared with NP swabs in VTM on both platforms. CONCLUSION: The Cepheid and BioFire® NGDS are viable options to address a variety of public health needs providing rapid and reliable, point-of-care testing using a variety of clinical matrices.

Evaluating sensitivity and specificity of the Biomeme Franklin™ three9 real-time PCR device and SARS-CoV-2 go-strips assay using clinical samples.

We evaluated the sensitivity and specificity of the Biomeme Franklin™ three9 Real-Time PCR Thermocycler and Biomeme SARS-CoV-2 Go-Strips in the detection of SARS-CoV-2. The Biomeme Franklin™ three9 platform is a portable, battery-operated system that could be used in remote settings. We assessed performance of the Biomeme SARS-CoV-2 detection system at a wide range of viral concentrations, examined cross-reactivity of the SARS-CoV-2 Go-Strips against several near-neighbor respiratory pathogens, and evaluated agreement against the BioFire® Respiratory Panel 2.1 in four clinical sample types. Our data indicate the Biomeme Go-Strips can reliably detect SARS-CoV-2 at a concentration of 4.2 × 103 copies/mL. No cross reactivity of the Go-Strips targets was detected against any of the tested near-neighbor respiratory pathogens. Cohen's kappa statistics ranged from 0.68 to 0.92 between results from the Biomeme SARS-CoV-2 Go-Strips and the BioFire® Respiratory Panel 2.1 in all the different sample types. Compared to the BioFire® Respiratory Panel 2.1, the Biomeme SARS-CoV-2 Go-Strips demonstrated statistically significantly lower sensitivity in 3 out of 5 sample types. Overall, our study demonstrates the Biomeme Franklin™ three9 used with the SARS-CoV-2 Go-Strips is an effective system for the detection of SARS-CoV-2 that could potentially be used in a remote or austere environment.

Fermented Duckweed as a Potential Feed Additive with Poultry Beneficial Bacilli Probiotics.

In this study, the duckweed varieties Lemna minor, Spirodela polyrhiza, and a commercially processed duckweed food supplement were investigated as potential substrates for the propagation of two probiotic Bacillus strains, B. subtilis KATMIRA1933 and B. amyloliquefaciens B-1895. Both L. minor and S. polyrhiza were found to be suitable substrates for the propagation of both bacilli, with 8.47-9.48 Log CFU/g and 10.17-11.31 Log CFU/g after 24 and 48 h growth on the substrates, respectively. The commercial duckweed product was a less favorable substrate, with growth reaching a maximum of 7.89-8.91 CFU/g after 24 h with no further growth after 48 h. Growth and adherence of the bacilli to the three products were confirmed via electron microscopy. These strains have demonstrated health-promoting benefits for poultry and thereby have the potential to enhance duckweed as an animal feed through the process of fermentation. Duckweed has been shown to be a promising alternative resource for protein and has the opportunity to become a valuable resource in multiple industries as a potential means to increase sustainability, food security, and reduce environmental impact.

Evaluation of an Industrial Soybean Byproduct for the Potential Development of a Probiotic Animal Feed Additive with Bacillus Species.

Probiotics are gaining public attention for their application in animal husbandry due to their ability to promote growth and prevent infections. Bacillus subtilis KATMIRA1933 and Bacillus amyloliquefaciens B-1895 are two spore-forming probiotic microorganisms that have been demonstrated to provide health benefits for poultry when supplemented into their diet. These strains can be propagated on a wide range of substrates, including soybean-derived byproducts from the food processing industry. Soybean-derived byproducts are often incorporated into animal feeds, but the value of an additive could potentially be increased by the addition of probiotic microorganisms, which may decrease production costs and reduce environmental impact. In this study, a soybean byproduct and a desalted version of this byproduct were evaluated as potential substrates for the growth of two probiotic bacilli species. Chemical analysis of these byproducts showed favorable carbohydrate, fat, and amino acid profiles, which were not affected by the desalting process. The desalted byproduct was further evaluated as a substrate for the growth of B. subtilis KATMIRA1933 and B. amyloliquefaciens B-1895 under solid-state conditions, and samples from this experiment were visualized by scanning electron microscopy. The results of this study indicate that the desalted soybean byproduct is a suitable substrate for the propagation of the two Bacillus species, which grew to numbers sufficient for the formulation of a probiotic animal feed additive.

Cognitive functioning in children with pantothenate-kinase-associated neurodegeneration undergoing deep brain stimulation.

AIM: To examine the cognitive functioning of young people with pantothenate-kinase-associated neurodegeneration (PKAN) after pallidal deep brain stimulation (DBS). PKAN is characterized by progressive generalized dystonia and has historically been associated with cognitive decline. With growing evidence that DBS can improve motor function in adults and children with PKAN, there is now the opportunity to study the cognitive profiles of these patients over time. METHOD: We present a case series of seven children (mean age 11 y 7 mo, SD 3 y 2 mo) undergoing bilateral pallidal DBS for the management of severe PKAN-associated dystonia. We administered standardized measures of intellectual ability and memory where possible, before DBS and 1 to 4 years after DBS. RESULTS: No cognitive decline was observed and scores improved in all but one child (whose dystonia could not be adequately controlled owing to multiple medical problems). In line with a stabilization or reduction in their dystonia, all but one child was able to tolerate longer assessment sessions and complete either the same or a greater number of subtests. INTERPRETATION: These findings suggest that apparent cognitive impairments may reflect difficulties in accessing cognition owing to severity of dystonia. Intellectual decline previously associated with PKAN may have been overestimated.

The TE4D-Cog: a new test for detecting early dementia in English-speaking populations.

BACKGROUND: The screening test usually used to detect dementia (Mini Mental State Examination, MMSE) is limited by a ceiling effect and high false positive rates, as are other similar instruments. There is therefore a need for a more sensitive and specific screening tool to aid early detection and diagnosis of dementia. OBJECTIVE: The hypothesis of the study was that the TE4D-Cog would be more sensitive and specific than the MMSE in detecting mild cognitive impairment in patients with AD. METHOD: The TE4D (Test for the Early Detection of Dementia from Depression) was adapted from its original German version for English-speaking populations. This new scale (the TE4D-Cog) was then administered together with the MMSE and the cognitive subscale of the Alzheimer's disease Assessment Scale (ADAS-Cog) to 178 people with a diagnosis of Alzheimer's disease and 25 cognitively intact comparators. The sensitivity and specificity in detecting dementia of the TE4D-Cog and the MMSE were compared in those with mild dementia and those without dementia. RESULTS: The TE4D-cog had high sensitivity with an acceptable specificity and low false positive rate. It also had good concurrent validity, high inter-rater reliability, good internal consistency and strong predictive validity. CONCLUSIONS: The TE4D-Cog is easy to administer, short and acceptable. Results are independent of age, gender and level of education. The TE4D-Cog may therefore be a useful alternative to the MMSE as a dementia screening instrument.

Anxiety and depression in family caregivers of people with Alzheimer disease: the LASER-AD study.

OBJECTIVE: There are high rates of stress, distress, and psychological illness in family caregivers of people with dementia. Female caregivers and those caring for people with neuropsychiatric symptoms are particularly at risk. The authors report on the prevalence of anxiety and depression in a sample of family caregivers of people with Alzheimer disease (AD) and compare the characteristics of those who did or did not have those conditions. METHODS: A group of 153 people with AD and their caregivers were interviewed as part of a larger study of AD. RESULTS: In all, 23.5% of caregivers scored at or above caseness level for anxiety, and 10.5%, at levels for depression. Care-recipient (CR) activities of daily living (ADL) impairment, being a caregiver living with the CR, being a female caregiver, reporting a poorer quality of relationship with the CR, and caregivers reporting their health as being poor all predicted anxiety disorder. CR irritability, caregivers reporting poor health, and a poorer quality of relationship with the CR predicted depression. CONCLUSIONS: Clinicians should be aware of the high rates of anxiety as well as depressive symptoms in family caregivers of people with AD, especially in female caregivers. CRs and Caregivers' impaired physical health put them at risk for psychological morbidity and should be treated energetically. A poor-quality relationship between the caregiver and the CR predicts both caregiver depression and anxiety. Caregivers living with the CR are much more likely to be anxious than depressed.

Shortage specialties: changes in career intentions from medical student to newly qualified doctor.

There is currently a shortage of doctors in Britain, especially in general practice, psychiatry and pathology. This study aimed to examine whether career intention, especially in the shortage specialties, changes between undergraduate level and graduation. The 234 participants were Senior House Officers and Pre-Registration House Officers, who had provided information about their career intentions in their fourth year of medical school. Participants completed a postal questionnaire about their current career intentions. 38.9% of medical students rising to 63.3% of doctors definitely intended to pursue a particular specialty. While the numbers of people who definitely wanted to pursue general practice and psychiatry increased, in line with nearly all other specialties, the overall attractiveness of these shortage specialties fell. Early career advice and support during medical school and immediately after graduation may help doctors to be confident in pursuing shortage specialties to which they were originally attracted.