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This letter, published in the Journal of Neurology, discusses a case report of a patient with deep brain stimulation (DBS) who experienced a relapse of dystonia despite normal impedance measurements. The patient had a complete unilateral extension fracture, which was not detected by impedance testing. The delay in diagnosing the fracture could have had serious consequences for the patient. The authors emphasize the importance of radiological examination in cases of sudden deterioration in DBS patients, as normal impedance measurements do not rule out hardware malfunction. They also highlight the potential risks of performing an MRI in patients with broken leads or cables. [Extracted from the article]

The seventh edition of the AASHTO LRFD Bridge Design Specifications (2016 interim) includes revised provisions for the design of deep beams using the strut-and-tie method. The validity and accuracy of these provisions as applied to simply supported deep beams loaded in a manner that generates an inflection point between the supports was investigated in this research. As part of a course-related laboratory investigation, graduate students at the University of Texas at Austin used these provisions to design two reduced-scale deep beams. The specimens were subsequently constructed and tested. The experimental behaviors of the specimens including governing failure modes, load-displacement curves, and their ultimate capacities were investigated and compared with estimates developed from the strutand-tie method. The results obtained validated the suitability of the revised provisions for the design of deep beams with inflection points located between supports. Additionally, the students developed pre-test estimates for the behaviors and strengths of the two deep beam specimens using the finite element software program VecTor2. While there was some variation among the computed responses, the blind predictions accurately captured governing failure modes and provided reasonable capacity estimates. [ABSTRACT FROM AUTHOR]

Management of Parkinson's disease (PD) using deep brain stimulation (DBS) requires complex care in specialized, multidisciplinary centers. A well-organized, efficient patient flow is crucial to ensure that eligible patients can quickly access DBS. Delays or inefficiencies in patient care may impact a center's ability to meet demand, creating a capacity bottleneck. Analysis of the current practices within a center may help identify areas for improvement. After external audit of the DBS workflow of the Lyon Neurological Hospital and comparison with other European centers, manageable steps were suggested to restructure the care pathway. Propositions of the audit comprised, for example: (1) directly admitting referred patients to hospital, without a prior neurological outpatient visit and (2) including the preoperative anesthesia consultation in the hospital stay 1 month before surgery, not separately. This reorganization (between 2013 and 2016) was performed without increases in hospital medical resources or costs. The time from patients' first referral to surgery was reduced (from 22 to 16 months; p = 0.033), as was the number of pre- and postoperative patient visits (11-5; p = 0.025) and the total cumulative length of in-hospital stay (20.5-17.5 nights; p = 0.02). Ultimately, the total number of PD consultations increased (346-498 per year), as did the number of DBS implants per year (32-45 patients). In this single center experience, restructuring the DBS care pathway allowed a higher number of PD patients to benefit from DBS therapy, with a shorter waiting time and without decreasing the quality of care. [ABSTRACT FROM AUTHOR]

Prosaposin ( PSAP) deficiency is an ultra-rare, fatal infantile lysosomal storage disorder ( LSD) caused by variants in the PSAP gene, with seven subjects reported so far. Here, we provide the clinical, biochemical and molecular characterization of two additional PSAP deficiency cases. Lysoplex, a targeted resequencing approach was utilized to identify the variant in the first patient, while quantification of plasma lysosphingolipids ( lysoSLs), assessed by liquid chromatography mass spectrometry ( LC-MS/ MS) and brain magnetic resonance imaging ( MRI), followed by Sanger sequencing allowed to attain diagnosis in the second case. Functional studies were carried out on patients' fibroblast lines to explore the functional impact of variants. The two patients were homozygous for two different truncating PSAP mutations (c. 895G>T, p.Glu299*; c.834_835delGA, p. Glu278Aspfs*27). Both variants led to a complete lack of processed transcript. LC-MS/ MS and brain MRI analyses consistently provided a distinctive profile in the two children. Quantification of specific plasma lysoSLs revealed elevated levels of globotriaosylsphingosine ( LysoGb3) and glucosylsphingosine ( GlSph), and accumulation of autophagosomes, due to a decreased autophagic flux, was observed. This report documents the successful use of plasma lysoSLs profiling in the PSAP deficiency diagnosis, as a reliable and informative tool to obtain a preliminary information in infantile cases with complex traits displaying severe neurological signs and visceral involvement. [ABSTRACT FROM AUTHOR]

1 - To assess the anatomical localization of the active contacts of deep brain stimulation targeted to the subthalamic nucleus (STN) in Parkinson’s disease patients. 2 - To analyze the stereotactic spatial distribution of the active contacts in relation to the dorsal and the ventral electrophysiologically-defined borders of the STN and the stereotactic theoretical target. Twenty-eight patients underwent bilateral high-frequency stimulation of the STN (HFS-STN). An indirect anatomical method based on ventriculography coupled to electrophysiological techniques were used to localize the STN. Clinical improvement was evaluated by Unified Parkinson’s Disease Rating Scale motor score (UPDRS III). The normalized stereotactic coordinates of the active contact centres, dorsal and ventral electrophysiologically-defined borders of the STN were obtained from intraoperative X-rays images. These coordinates were represented in a three-dimensional stereotactic space and in the digitalized atlas of the human basal ganglia. HFS-STN resulted in significant improvement of motor function (62.8%) in off-medication state and levodopa-equivalent dose reduction of 68.7% (p < 0.05). Most of the active contacts (78.6%) were situated close to (± 1.6 mm) the dorsal border of the STN (STN-DB), while 16% were dorsal and 5.4% were ventral to it. Similar distribution was observed in the atlas. The euclidean distance between the STN-DB distribution center and the active contacts distribution center was 0.31 mm, while the distance between the active contacts distribution center and the stereotactic theoretical target was 2.15 mm. Most of the space defined by the active contacts distribution (53%) was inside that defined by the STN-DB distribution. In our series, most of the active electrodes were situated near the STN-DB. This suggests that HFS-STN could influence not only STN but also the dorsal adjacent structures (zona incerta and/or Fields of Forel). [ABSTRACT FROM AUTHOR]

In this article we report the growth and optical defect characterization of a novel family of alkali halide crystals, produced by the mixing of four ionic salts. These quaternary crystals imply the existence of four ternary crystals, one of these recently studied. The characterization is applied to two crystals with different component concentrations, one of these with a Europium impurity (an impurity with high optical sensitivity). We obtain the lattice constant by X-ray diffractometry. The optical absorption spectra of irradiated crystals show a single F band. The Generalized Vegard's law, applied to the novel ternary system recently studied, was extended to the quaternary crystal. Good agreement with the experimental results was obtained. [ABSTRACT FROM AUTHOR]

This paper addresses the experimental and theoretical investigations of mechanical properties of polymer resins reinforced with natural fibers. These materials have potentially a wide area of applications and relatively low cost because they are made of inexpensive resins and fibers obtained from plants available in the Mexican desert. We present the results of experimental investigations of elastic properties and strength of composites based on three types of polymer resins reinforced with natural fibers of Palma Zamandoca. Theoretical analysis of effective elastic and strength properties of short-fiber matrix composites is given based on the advanced self-consistent scheme permitting to account for interactions between fibers. The method utilizes the idea of introducing the effective strain field which affects every inclusions in the composite. In distinction to the traditional forms of the effective (i.e., self-consistent) field method we assume that the effective field is not constant and the same for all fibers but rather depends on the orientation of each of them. This allows to take into account the characteristics of the spatial distributions of fibers in the volume of composite. The scheme utilizes the asymptotic solution of elastic problem for rigid cylindrical bar. The results of theoretical analysis are compared with extensive experimental data on composites with natural fibers manufactured and tested by the authors as well as with the data for composites with inorganic fibers (e.g., glass and carbon fibers) available in literature. [ABSTRACT FROM PUBLISHER]

By using a commercial polyester resin as the matrix and a natural fiber grass (palma samandoca) as the reinforcement material, a composite was prepared. A technique was developed for the preparation of samples and moulds for testing were built based upon standards and the samples were characterized mechanically. These results indicate that there exists a concentration and length of fiber for which a maximum resistance and rigidity is obtained for the composite as compared to the pure resin. [ABSTRACT FROM PUBLISHER]

Two samples of commercially-available styrene-butadiene block copolymers (SBC) were tested for suitability for use in biomedical applications. A 30% sample and a 40% sample of styrene-containing polymers with very similar molecular weights (approximately 300,000) were characterized before and after being placed in a physiological serum for a period of six months. SEM, FTIR, and atomic absorption spectroscopy were used to characterize the polymers. Scanning and transmission electron micrographs showed that the SBC's morphology was clearly affected by the serum. A difference was observed with the higher styrene-containing polymer which showed no degradation of the elastomeric portion of the copolymer, whereas the 30% sample showed that considerable degradation occurred in this area. Atomic absorption results showed a clear difference in the capability of both materials to absorb K+, Na+ and Caions with a clear advantage for the 40% styrene-containing material. FTIR results indicate that both polymer samples degraded in the serum, showing loss of both the polystyrene and polybutadiene portions, as well as oxidation of the double bonds in the latter. [ABSTRACT FROM PUBLISHER]

FT-Raman spectroscopy of commercial amorphous and crystalline nylon 6-12 filaments subjected to various γ-radiation doses are presented. The results show that a difference exists in the interaction of γ-radiation with these polyamides, depending on the crystallinity which can be evaluated by measuring the CH-stretching/CH-bending Raman band intensity ratio as a function of applied γ-dose. [ABSTRACT FROM AUTHOR]

Commercial nylon 6-12 fibers were subjected to various doses of γ-radiation. The mechanical and some thermal properties, as compared to those of non-irradiated fibers, show changes which are discussed in terms of the radiation-matter interactions. [ABSTRACT FROM AUTHOR]

Purpose.To show the feasibility and consequences at 1 year of the use of the International Classification of Functioning, Disability and Health, version for Children and Youth (ICF-CY) in the process of social and scholastic inclusion for students with disability in a district of Northeastern Italy (Treviso province). Methods.We describe the novel procedure for inclusion of students with disability launched by disability and education Services of the Treviso Province. The protocol was organized in four steps and involved health professionals and teachers throughout the whole Province. The implementation was preceded by intensive exposure of the involved professionals to the ICF-CY model and structure and by workshops in which the participants elaborated the actual documents accompanying the process of scholastic inclusion according to the specific Law (104/1992): the notification card, the identification of the student with disabilities, the functional diagnosis, the dynamic functional profile and the individual educational plan. Results.The results show that the adherence to the new protocol was very satisfactory, as well as the perceived validity and relevance of the new documents elaborated with ICF language. The experimentation in progress provided interesting indications on the way to apply the ICF-CY to the scholastic inclusion processes. Conclusions.The largest alphabetization effort on ICF attempted in a Public Health System (disability service) and in the school system improve the social and scholastic participation of student with disability and can reduce the barriers in the environment. [ABSTRACT FROM AUTHOR]