Optical microscope and tapered fiber coupling apparatus for a dilution refrigerator

We have developed a system for tapered fiber measurements of optomechanical resonators inside a dilution refrigerator, which is compatible with both on- and off-chip devices. Our apparatus features full three-dimensional control of the taper-resonator coupling conditions enabling critical coupling, with an overall fiber transmission efficiency of up to 70%. Notably, our design incorporates an optical microscope system consisting of a coherent bundle of 37,000 optical fibers for real-time imaging of the experiment at a resolution of ∼1 μm. We present cryogenic optical and optomechanical measurements of resonators coupled to tapered fibers at temperatures as low as 9 mK.

Clinical and neuroimaging factors associated with 30-day fatality among indigenous West Africans with spontaneous intracerebral hemorrhage

BACKGROUND

Spontaneous intracerebral hemorrhage (ICH) is associated with a high case fatality rate in resource-limited settings. The independent predictors of poor outcome after ICH in sub-Saharan Africa remains to be characterized in large epidemiological studies. We aimed to determine factors associated with 30-day fatality among West African patients with ICH.

METHODS

The Stroke Investigative Research and Educational Network (SIREN) study is a multicentre, case-control study conducted at 15 sites in Nigeria and Ghana. Adults aged ≥18 years with spontaneous ICH confirmed with neuroimaging. Demographic, cardiovascular risk factors, clinical features and neuroimaging markers of severity were assessed. The independent risk factors for 30-day mortality were determined using a multivariate logistic regression analysis with an adjusted odds ratio (OR) and 95% confidence interval (CI).

RESULTS

Among 964 patients with ICH, 590 (61.2%) were males with a mean age (SD) of 54.3(13.6) years and a case fatality of 34.3%. Factors associated with 30-day mortality among ICH patients include: Elevated mean National Institute of Health Stroke Scale(mNIHSS);(OR 1.06; 95% CI 1.02-1.11), aspiration pneumonitis; (OR 7.17; 95% CI 2.82-18.24), ICH volume > 30mls; OR 2.68; 95% CI 1.02-7.00)) low consumption of leafy vegetables (OR 0.36; 95% CI 0.15-0.85).

CONCLUSION

This study identified risk and protective factors associated with 30-day mortality among West Africans with spontaneous ICH. These factors should be further investigated in other populations in Africa to enable the development of ICH mortality predictions models among indigenous Africans.

B-30 Sturge-Weber Syndrome in Adulthood: A Case Study of Superior Cognitive Reserve

Objective

Sturge-Weber Syndrome (SWS) is a neurological disorder usually diagnosed in childhood and characterized by facial port-wine stains, seizures, and intracranial vascular malformations. SWS is associated with a variety of neuropsychological presentations in children, but the adult cognitive profile of this disease is not well established. Specifically, little is known about how cerebral abnormalities found using Magnetic Resonance Imaging (MRI) correlate with cognitive difficulties in adulthood or if certain prognostic factors can predict cognitive outcome.

Methods

The present case involved a 53-year-old, left-handed, Caucasian female with 20 years of education with SWS, possible seizures, multiple concussions, posttraumatic stress disorder (PTSD; multiple reported traumas) and bipolar disorder, referred for a neuropsychological evaluation for progressive problems with memory, word-finding, and coordination over the last 14 years. A neuropsychological evaluation was administered and structural neuroimaging was reviewed.

Results

MRI studies revealed left hemispheric atrophy with enlargement of the left ventricle, cortical calcification in the left temporo-occipital region, cerebrovascular disease particularly in the frontal lobes, and vascular malformations. Despite severe neuroanatomical abnormalities associated with SWS, as well as comorbid psychiatric disorders, a neuropsychological evaluation revealed a relatively intact cognitive profile, with only scattered minor inefficiencies in attention/processing speed, executive functioning, and motor functioning.

Conclusions

This case provided an example of good prognosis of SWS in adulthood, despite significant brain abnormalities, potential seizure activity, multiple concussions, and psychiatric comorbidity. Further research is needed to conceptualize the neuropsychological impact of SWS in adulthood, specifically whether aspects of superior cognitive reserve (e.g., higher education) are associated with better prognosis.

Neuropsychological Considerations of the Cultural and Linguistic Challenges of Working with a Bilingual/Bicultural Patient with Multiple System Atrophy (MSA): A Case Report

Objective

This case highlights the importance of understanding bilingualism, English as a second language (ESL), immigration as an older adult, and acculturation, in light of neuropsychological test results of an individual with MSA.

Case Description

Mrs. X is a right-handed, 73-year-old, South African woman. Her first language is Afrikaans while her second language is English. She has a history of MSA (2015). She reported a significant decline in her previously mastered English fluency. Challenges with language (i.e., reading comprehension, conversation), focus, balance, and activities of daily living, bilateral arm jerks, and difficulties with ambulation, Pisa Syndrome (left), loss of appetite, incontinence, fluctuating temperature, depression, personality changes, and suspected auditory hallucinations were also expressed.

Diagnostic Impressions and Outcomes

The neurocognitive findings indicated global impairment. Aside from an average score in her reading recognition, and low-average in a test of mental flexibility, Mrs. X had impairment in attention, learning, immediate and delayed memory, executive functioning, receptive and expressive language, confrontation naming, and visuospatial abilities. Mrs. X’s motoric difficulties and parkinsonism made it difficult for her to participate in testing comfortably. Language barriers were prominent: Mrs. X occasionally required English-Afrikaans translation and multiple repetitions of prompts. Summary and impressions of test results acknowledged the cultural and linguistic limitations of the evaluation. She was diagnosed with Major Neurocognitive Disorder secondary to MSA.

Discussion

In patients with diffuse impairment, it is essential to understand the role of dual language processes, ESL, and cultural limitations of assessments in order to accurately differentiate between neurodegenerative processes (i.e., Alzheimer’s Disease vs. other disorders), as well as to determine the impact of MSA on the linguistic abilities of bilingual individuals.