143 research outputs found
Lithium Phthalocyanine: A Probe for Electron Paramagnetic Resonance Oximetry in Viable Biological Systems.
Lithium phthalocyanine (LiPc) is a prototype of another generation of synthetic, metallic-organic, paramagnetic crystallites that appear very useful for in vitro and in vivo electron paramagnetic resonance oximetry. The peak-to-peak line width of the electron paramagnetic resonance spectrum of LiPc is a linear function of the partial pressure of oxygen (pO2); this linear relation is independent of the medium surrounding the LiPc. It has an extremely exchange-narrowed spectrum (peak-to-peak line width = 14 mG in the absence of O2). Physicochemically LiPc is very stable; its response to pO2 does not change with conditions and environments (e.g., pH, temperature, redox conditions) likely to occur in viable biological systems. These characteristics provide the sensitivity, accuracy, and range to measure physiologically and pathologically pertinent O2 tensions (0.1-50 mmHg; 1 mmHg = 133 Pa). The application of LiPc in biological systems is demonstrated in measurements of pO2 in vivo in the heart, brain, and kidney of rats
International Centre for Guidance Studies (iCeGS) Annual Review 2023 - 25th Anniversary
This publication offers a brief insight into the wide range of activities the iCeGS team has been involved with over the year and the last 25 years. It explores our contribution to policy, research and practice within the career development sector both in the UK and wider afield. iCeGS Annual Review also allows the team to reflect on our many achievements over the last year. Like other years, we feel particularly proud of several activities this year
AI (r)evolution â where are we heading? Thoughts about the future of music and sound technologies in the era of deep learning
Other Side of Breast Cancer: Factors Associated with Caregiver Burden
Purpose This study aimed to determine factors associated with caregiver burden among primary caregivers of women with breast cancer in Iran. Methods This was a descriptive correlation study conducted in 2012 on 150 main caregivers of patients with breast cancer who came to the oncology clinic of Shahid Ghazi hospital in Tabriz, Iran. A questionnaire which included caregiving-related factors and the Zarit Burden Interview was used for data collection after its validity and reliability were determined. Data was analyzed using SPSS 13.0 software with descriptive and analytic statistics. The association between significant variables and the dependent variable with an observation of the effects of other variables was assessed using the multiple linear regression model. Results The mean age of caregivers was 39.60 ñ 13.80 years old, and 77 (51.3) of them were men. The mean score of the Zarit Burden Interview was 30.55 ñ 19.18. In the regression model, the mean score of activities of daily living, level of education, gender, and financial status were identified as the determining factors of the burden of caregivers. Conclusions Primary caregivers need to be financially supported by the relevant organizations. Care skills training and providing palliative care seem helpful in reducing the pain and the burden of family caregivers for patients with breast cancer. é 201
Reactive direction control for a mobile robot: A locust-like control of escape direction emerges when a bilateral pair of model locust visual neurons are integrated
Locusts possess a bilateral pair of uniquely identifiable visual neurons that respond vigorously to
the image of an approaching object. These neurons are called the lobula giant movement
detectors (LGMDs). The locust LGMDs have been extensively studied and this has lead to the
development of an LGMD model for use as an artificial collision detector in robotic applications.
To date, robots have been equipped with only a single, central artificial LGMD sensor, and this
triggers a non-directional stop or rotation when a potentially colliding object is detected. Clearly,
for a robot to behave autonomously, it must react differently to stimuli approaching from
different directions. In this study, we implement a bilateral pair of LGMD models in Khepera
robots equipped with normal and panoramic cameras. We integrate the responses of these LGMD
models using methodologies inspired by research on escape direction control in cockroaches.
Using ârandomised winner-take-allâ or âsteering wheelâ algorithms for LGMD model integration,
the khepera robots could escape an approaching threat in real time and with a similar
distribution of escape directions as real locusts. We also found that by optimising these
algorithms, we could use them to integrate the left and right DCMD responses of real jumping
locusts offline and reproduce the actual escape directions that the locusts took in a particular
trial. Our results significantly advance the development of an artificial collision detection and
evasion system based on the locust LGMD by allowing it reactive control over robot behaviour.
The success of this approach may also indicate some important areas to be pursued in future
biological research
A global survey on changes in the supply, price, and use of illicit drugs and alcohol, and related complications during the 2020 COVID-19 pandemic
Background and Aims : COVID-19 has infected more than 77 million people worldwide and impacted the lives of many more, with a particularly devastating impact on vulnerable populations, including people with substance use disorders (SUDs). Quarantines, travel bans, regulatory changes, social distancing, and "lockdown" measures have affected drug and alcohol supply chains and subsequently their availability, price, and use patterns, with possible downstream effects on presentations of SUDs and demand for treatment. Given the lack of multicentric epidemiologic studies, we conducted a rapid global survey within the International Society of Addiction Medicine (ISAM) network in order to understand the status of substance-use patterns during the current pandemic. Design : Cross-sectional survey. Setting : Worldwide. Participants : Starting on April 4, 2020 during a 5-week period, the survey received 185 responses from 77 countries. Measurements : To assess addiction medicine professionals' perceived changes in drug and alcohol supply, price, use pattern, and related complications during the COVID-19 pandemic. Findings : Participants reported (among who answered "decreased" or "increased") a decrease in drug supply (69.0%) and at the same time an increase in price (95.3%) globally. With respect to changes in use patterns, an increase in alcohol (71.7%), cannabis (63.0%), prescription opioids (70.9%), and sedative/hypnotics (84.6%) use was reported, while the use of amphetamines (59.7%), cocaine (67.5%), and opiates (58.2%) was reported to decrease overall. Conclusions : The global report on changes in the availability, use patterns, and complications of alcohol and drugs during the COVID-19 pandemic should be considered in making new policies and in developing mitigating measures and guidelines during the current pandemic (and probable future ones) in order to minimize risks to people with SUD.Publisher PDFPeer reviewe
A Survey of Air-to-Ground Propagation Channel Modeling for Unmanned Aerial Vehicles
In recent years, there has been a dramatic increase in the use of unmanned
aerial vehicles (UAVs), particularly for small UAVs, due to their affordable
prices, ease of availability, and ease of operability. Existing and future
applications of UAVs include remote surveillance and monitoring, relief
operations, package delivery, and communication backhaul infrastructure.
Additionally, UAVs are envisioned as an important component of 5G wireless
technology and beyond. The unique application scenarios for UAVs necessitate
accurate air-to-ground (AG) propagation channel models for designing and
evaluating UAV communication links for control/non-payload as well as payload
data transmissions. These AG propagation models have not been investigated in
detail when compared to terrestrial propagation models. In this paper, a
comprehensive survey is provided on available AG channel measurement campaigns,
large and small scale fading channel models, their limitations, and future
research directions for UAV communication scenarios
Biallelic SQSTM1 mutations in early-onset, variably progressive neurodegeneration.
OBJECTIVE: To characterize clinically and molecularly an early-onset, variably progressive neurodegenerative disorder characterized by a cerebellar syndrome with severe ataxia, gaze palsy, dyskinesia, dystonia, and cognitive decline affecting 11 individuals from 3 consanguineous families. METHODS: We used whole-exome sequencing (WES) (families 1 and 2) and a combined approach based on homozygosity mapping and WES (family 3). We performed in vitro studies to explore the effect of the nontruncating SQSTM1 mutation on protein function and the effect of impaired SQSTM1 function on autophagy. We analyzed the consequences of sqstm1 down-modulation on the structural integrity of the cerebellum in vivo using zebrafish as a model. RESULTS: We identified 3 homozygous inactivating variants, including a splice site substitution (c.301+2T>A) causing aberrant transcript processing and accelerated degradation of a resulting protein lacking exon 2, as well as 2 truncating changes (c.875_876insT and c.934_936delinsTGA). We show that loss of SQSTM1 causes impaired production of ubiquitin-positive protein aggregates in response to misfolded protein stress and decelerated autophagic flux. The consequences of sqstm1 down-modulation on the structural integrity of the cerebellum in zebrafish documented a variable but reproducible phenotype characterized by cerebellum anomalies ranging from depletion of axonal connections to complete atrophy. We provide a detailed clinical characterization of the disorder; the natural history is reported for 2 siblings who have been followed up for >20 years. CONCLUSIONS: This study offers an accurate clinical characterization of this recently recognized neurodegenerative disorder caused by biallelic inactivating mutations in SQSTM1 and links this phenotype to defective selective autophagy
Using hydroxyl radical footprinting to explore the free energy landscape of protein folding.
Characterisation of the conformational states adopted during protein folding, including globally unfolded/disordered structures and partially folded intermediate species, is vital to gain fundamental insights into how a protein folds. In this work we employ fast photochemical oxidation of proteins (FPOP) to map the structural changes that occur in the folding of the four-helical bacterial immunity protein, Im7. Oxidative footprinting coupled with mass spectrometry (MS) is used to probe changes in the solvent accessibility of amino acid side-chains concurrent with the folding process, by quantifying the degree of oxidation experienced by the wild-type protein relative to a kinetically trapped, three-helical folding intermediate and an unfolded variant that lacks secondary structure. Analysis of the unfolded variant by FPOP-MS shows oxidative modifications consistent with the species adopting a solution conformation with a high degree of solvent accessibility. The folding intermediate, by contrast, experiences increased levels of oxidation relative to the wild-type, native protein only in regions destabilised by the amino acid substitutions introduced. The results demonstrate the utility of FPOP-MS to characterise protein variants in different conformational states and to provide insights into protein folding mechanisms that are complementary to measurements such as hydrogen/deuterium exchange labelling and Ί-value analysis
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