Tangential velocity constraint for orbital maneuvers with Theory of Functional Connections

Maneuvering a spacecraft in the cislunar space is a complex problem, since it is highly perturbed by the gravitational influence of both the Earth and the Moon, and possibly also the Sun. Trajectories minimizing the needed fuel are generally preferred in order to decrease the mass of the payload. A classical method to constrain maneuvers is mathematically modeling them using the Two Point Boundary Value Problem (TPBVP), defining spacecraft positions at the start and end of the trajectory. Solutions to this problem can then be obtained with optimization techniques like the nonlinear least squares conjugated with the Theory of Functional Connections (TFC) to embed the constraints, which recently became an effective method for deducing orbit transfers. In this paper, we propose a tangential velocity (TV) type of constraints to design orbital maneuvers. We show that the technique presented in this paper can be used to transfer a spacecraft (e.g. from the Earth to the Moon) and perform gravity assist maneuvers (e.g. a swing-by with the Moon). In comparison with the TPBVP, solving the TV constraints via TFC offers several advantages, leading to a significant reduction in computational time. Hence, it proves to be an efficient technique to design these maneuvers.

Use of non-invasive stimulation in movement disorders: a critical review

BACKGROUND

Noninvasive stimulation has been widely used in the past 30 years to study and treat a large number of neurological diseases, including movement disorders.

OBJECTIVE

In this critical review, we illustrate the rationale for use of these techniques in movement disorders and summarize the best medical evidence based on the main clinical trials performed to date.

METHODS

A nationally representative group of experts performed a comprehensive review of the literature in order to analyze the key clinical decision-making factors driving transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) in movement disorders. Classes of evidence and recommendations were described for each disease.

RESULTS

Despite unavoidable heterogeneities and low effect size, TMS is likely to be effective for treating motor symptoms and depression in Parkinson's disease (PD). The efficacy in other movement disorders is unclear. TMS is possibly effective for focal hand dystonia, essential tremor and cerebellar ataxia. Additionally, it is likely to be ineffective in reducing tics in Tourette syndrome. Lastly, tDCS is likely to be effective in improving gait in PD.

CONCLUSIONS

There is encouraging evidence for the use of noninvasive stimulation on a subset of symptoms in selected movement disorders, although the means to optimize protocols for improving positive outcomes in routine clinical practice remain undetermined. Similarly, the best stimulation paradigms and responder profile need to be investigated in large clinical trials with established therapeutic and assessment paradigms that could also allow genuine long-term benefits to be determined.

Cannabinoids in Neurology - Position paper from Scientific Departments from Brazilian Academy of Neurology

Cannabinoids comprehend endocannabinoids, phytocannabinoids, and synthetic cannabinoids, with actions both in the central and peripherical nervous systems. A considerable amount of publications have been made in recent years, although cannabis has been known for over a thousand years. Scientific Departments from the Brazilian Academy of Neurology described evidence for medical use in their areas. Literature is constantly changing, and possible new evidence can emerge in the next days or months. Prescription of these substances must be discussed with patients and their families, with knowledge about adverse events and their efficacy.

Neuropsychiatric symptoms as first manifestation of olfactory groove meningioma - importance of neuroimaging evaluation

Introduction

Neuropsychiatric symptoms may be the first and only manifestation of brain tumours, while classic neurological symptoms and signs may be minimal or absent at first. These patients will often receive psychiatric treatments for prolonged periods before correct diagnosis.

Objectives

To report the case of a patient with olfactory groove meningioma presenting with neuropsychiatric symptoms as a basis for discussion.

Methods

Retrospective review of clinical notes, neuroimaging results and house photos. Literature review.

Results

A 66-year-old woman was brought by police to the psychiatric emergency department Her neighbours had notified authorities of a bad smell, and police found the house was loaded with garbage. The patients reported depressive symptoms in the last 6 months, including apathy, anhedonia, social isolation, decreased appetite and insomnia; loss of basic skills such as cooking or cleaning; she also reported dizziness and two episodes of urinary and faecal incontinence in public. The patient had a history of being medicated for depression between 2000 and 2006. Currently she was taking only alprazolam 1 mg daily. During evaluation she was conscious, oriented and cooperative, with evident hypomimia, psychomotor inhibition and indifferent attitude. Cranial nerve function was preserved except for anosmia. Cranial CT and MRI showed a solid extra-axial tumour of 5.2x3.5x4.9 centimetres compatible with meningioma of the olfactory groove, and she was referred to Neurosurgery for surgical intervention.

Conclusions

This case illustrates the importance of a thorough organic evaluation, including neuroimaging, in the differential diagnosis of patients with atypical symptoms before making a psychiatric diagnosis and instituting treatment.

Evaluation of the Effect of Brazilian Savanna (Cerrado) Seasons in Flavonoids and Alkaloids Accumulation: The Case of Duguetia furfuracea

Environmental factors can influence secondary plant metabolism, inducing seasonal variation in chemical composition. Few works report how the seasons of Brazilian savanna (Cerrado), rainy and dry, impacts plant metabolism. We investigated the seasonal effect on the production of secondary metabolites in Duguetia furfuracea. Leaves of three individuals were collected monthly for one year and analyzed by ultra-fast liquid chromatography coupled to diode array detector and mass spectrometry (UFLC-DAD-MS), partial least squares-discriminant analysis (PLS-DA), hierarchical cluster analysis (HCA), volcano plot, and Pearson correlation. The main chemical classes found were benzyltetrahydroisoquinoline derivatives and flavonoids. Alkaloids are virtually perennial, with qualitative variation during the year, and flavonoids accumulate during the rainy season. Dew point temperature seemed to be the most representative weather indicator in the metabolite change. These results showed for the first time the effect of the Cerrado environment on the levels of flavonoids and alkaloids in Duguetia furfuracea. They could be useful for exploring this species since it is used in popular medicine and accumulates valuable secondary metabolites.

The relationship between neuropsychological, emotional and family functioning within a group of patients with multiple sclerosis

MS is a heterogeneous entity that varies in its etiology, classification, clinical course and sequelae, and is included as part of the chronic diseases that cause limitations in many areas. This study aims to assess neuropsychological functions, anxiety and depression in patients with MS, and realize that these variables can be influenced by family functioning.

This study consists of a group of 25 individuals were women with diagnosis of Multiple Sclerosis (ages 25 to 58 years). Data collection was done through: a demographic questionnaire and clinical, a neuropsychological assessment battery (LNNB), a range of Hospital Anxiety and Depression Scale (HADS), and a questionnaire of family functioning (FACES-III). The results suggest that the group of patients evaluated present neuropsychological deficits in several areas, as well as depression and anxiety. They also suggest that there is a higher prevalence of neuropsychological deficits associated with a higher incidence of depressive symptoms and family dissatisfaction. Taken together, these results reveal an involvement of emotional and family functioning on neuropsychological functioning. As such, these factors should be considered in the implementation of intervention programs, both in terms of individual psychotherapy, or the level of family psychotherapy as well as in neuropsychological and psychosocial rehabilitation programs and these patients.

Portuguese consensus document for the management of alpha-1-antitrypsin deficiency

Alpha-1-antitrypsin deficiency (AATD) is a genetic autosomal codominant disorder caused by mutations in SERPINA1 gene. It is one of the most prevalent genetic disorders, although it remains underdiagnosed. Whereas at international level there are several areas of consensus on this disorder, in Portugal, inter-hospital heterogeneity in clinical practice and resources available have been adding difficulties in reaching a diagnosis and in making therapeutic decisions in this group of patients. This raised a need to draft a document expressing a national consensus for AATD. To this end, a group of experts in this field was created within the Portuguese Pulmonology Society - Study group on AATD, in order to elaborate the current manuscript. The authors reviewed the existing literature and provide here general guidance and extensive recommendations for the diagnosis and management of AATD that can be adopted by Portuguese clinicians from different areas of Medicine. This article is part of a supplement entitled "Portuguese consensus document for the management of alpha-1-antitrypsin deficiency" which is sponsored by Sociedade Portuguesa de Pneumologia.

Malignant transformation of a tracheal chondroma: The second reported case and review of the literature

Tracheal tumors are rare, representing only 0.2% of the respiratory tract malignancies. Chondrosarcoma arising in the trachea was first described in 1959 by Jackson et al. and since then only 20 cases have been described. We report the second documented case of malignant transformation from an endotracheal chondroma, in a 75-year-old woman, and review the literature.

Sensory tricks in focal dystonia and hemifacial spasm

BACKGROUND AND PURPOSE

Sensory tricks are sensory, often but not exclusively tactile, stimuli usually in the body part affected by the movement disorder that produce a meaningful alleviation of dystonia. The frequency and clinical features of sensory tricks in different types of dystonia are poorly studied in the literature. There is no information regarding the presence of a similar phenomenon in HFS.

METHODS

We enrolled consecutive patients who had the diagnosis of HFS (26) or the following types of dystonia: cervical dystonia (CD; 21); blepharospasm (BS; 20); and writer's cramp (WC; 10). Patients underwent a structured interview to assess the following items related to sensory trick: presence, type and effectiveness. Statistical analysis used the Verisimilitude Reason test and the significance level was set at 5%.

RESULTS

Sensory trick was more frequent in the CD group (81%) when compared with HFS (38.5%; P=0.004) and WC (20%; P=0.001), but there was no statistical difference from the frequency in BS patients (55%; P=0.078). The most common sensory tricks were facial massage (60%) in HFS; to touch the head with the hands (35.3% in CD); to touch the upper eyelid with the index finger and thumb (81.8%) in BS; and to touch the hand with the contralateral hand (100%) in WC.

CONCLUSIONS

Sensory tricks are common in all types of focal dystonia herein studied, although they are more frequent in CD. Patients with HFS also often display improvement of the movement disorder with tactile stimulation.

Takayasu's Arteritis in a Patient with Sydenham's Chorea: is There an Association?

BACKGROUND

Takayasu's arteritis (TA) has been associated with many conditions. Herein described is a case of TA in a patient with rheumatic fever complicated with Sydenham's chorea.

CASE REPORT

A 17-year-old female presented at age 6 with rheumatic fever followed by chorea a month later. At the age of 16, she developed a blood pressure discrepancy between the arms and faint pulses. Computed tomography angiography revealed diffuse aortic involvement and narrowing of the arteries.

DISCUSSION

The presence of rheumatic fever and Sydenham's chorea in TA raises the possibility of an immunological basis for the pathogenesis of the disease.

Multiple sclerosis: psychological and psychopathological study

Multiple Sclerosis (MS) is the most common demyelinating disease of the central nervous system and one that presents more neuropsychiatric manifestations.

The authors of this paper proposes to characterize psychological and psychopathologically a group of patients sent from Neurology to Psychiatry at St. João Hospital - Porto.

The initial group consisted of 48 patients (35 women and 13 men). Data collection was done through a semi-formant interview to obtain socio-demographic and clinical data. The psychological and psychopathological evaluation was made with the following tools: MMSE (Mini Mental State Examination), Raven, MOS SF-36 (Medical Outcomes Study 36-Item Short Form Health Survey), SCL-90 (Hopkins Symptoms Distress Checklist 90), HADS (Hospital Anxiety and Depression Scale), scale and EDSS (Expanded Disability Status Scale).

On this sample the median duration of disease was 11 years and the value of EDSS has an average of 2.49. The sample does not show significant levels of psychopathology. However the results suggest that the worse is the overall severity of MS (EDSS) and the greater the duration of illness, the worst seems to be general physical and emotional functioning. In this study, no associations were found between variables of MS and psychopathological findings. However cognitive dysfunction appears to worsen with the greatest severity of MS, as in other works.

Neuropsychological assessment in patients with multiple sclerosis

Multiple Sclerosis (MS) is one of the most common neurological diseases and disabling in young adults, who often have cognitive dysfunction.

The authors of this paper proposes to assess neuropsychological functions most affected in a group of MS patients and compares them with a group of healthy people.

This study consists of two groups: the group of patients with definite diagnosis of MS (n = 31) and the control group (n = 15). Data collection is done through a questionnaire sociodemographic and clinical data and a battery of neuropsychological assessment (Luria Nebraska Neuropsychological Battery). Data analysis is performed using the program SigmaStat.

The results show that the group of MS patients compared with the control group presented a significantly lower performance at various scales, and also indicate that in this patient group, there is no relationship between cognitive functioning and duration of disease (as noted in several studies).

This work also indicates a strong diagnostic validity of the Luria Nebraska Neuropsychological Battery, in the differentiation between normal individuals and patients in the neurological point of view (including patients with MS).

Treatment of Sydenham chorea with corticosteroids

Despite treatment with valproic acid and neuroleptics, a significant proportion of patients with Sydenham chorea (SC) remain with chorea. We evaluated the effect of intravenous methyl-prednisolone followed by oral prednisone in patients with SC refractory to conventional treatment. Patients were enrolled in the study if they failed to improve with conventional treatment, despite the development of side effects. Chorea was rated on a 0 to 4 score. Five patients, 3 of them women, were included in the study. The median pretreatment rating score of the chorea was 3 (range, 3-4) and dropped to 1 (range, 0-2) after a median follow-up of 7 months (range, 3-7 months). Two patients developed Cushing syndrome. Our data suggest that intravenous methyl-prednisolone followed by oral prednisone is an effective and well-tolerated treatment of refractory SC.

Development of Coronal Mass Ejections: Radio Shock Signatures

We present observational imaging evidence for the existence of metric radio bursts closely associated with the front edge of coronal mass ejections (CMEs). These radio bursts drift in frequency similarly to type II bursts. They are weak and usually go undetected on spectrograph data. We find the same measured projected velocity for the displacement of, respectively, the radio source (when observed at two or more frequencies) and the CME leading edge. The position of the emitting source coincides with the CME leading edge. Among the events analyzed, the fastest of them, with a velocity over 1400 km s-1, was associated with interplanetary type II bursts.

Pregnancy complicated by primary antiphospholipid antibody syndrome

BACKGROUND

Primary antiphospholipid antibody syndrome is a clinical entity that may threaten the health of both fetus and mother.

CASE

We report a fatal case of primary antiphospholipid antibody syndrome in a woman who developed catastrophic disease due to multisystem thrombosis in the postpartum period following a fetal death. Three years before her admission, primary antiphospholipid antibody syndrome was diagnosed on the basis of high titers of immunoglobulin G anticardiolipin antibody, a positive lupus anticoagulant, a false-positive VDRL, and fibrin deposits in the biopsy of a palmar lesion.

CONCLUSION

The physician must recognize the potentially catastrophic complications of pregnancy and the postpartum period in patients with antiphospholipid antibodies, and appropriate patient counseling should be provided.