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The moduli set {2n-1 - 1; 2n+1 - 1; 2n; 2n - 1} has been recently proposed in literature for class of 4n-bit dynamic range in residue number system. Due to only utilizing modulus in the form of 2k - 1 besides modulo 2n, this moduli set enjoys the efficient Arithmetic Unit (AU) in its architecture. Not only does the efficiency of a RNS system depend on the residue arithmetic unit but it also is limited to the residue to binary converter. In this paper, a new two level residue-to-binary converter architecture based on Mixed Radix Conversion (MRC) is presented for the aforementioned moduli set. The proposed converter includes two levels of design based on MRC properties. Firstly, the 3-moduli subset {2n-1 - 1; 2n+1 - 1; 2n - 1} is properly organized and as it does not calculate several values, it results in some cost modifications. Eventually, a two-moduli set {- 2n-1 - 1 -2n+1 - 1 (2n - 1) ; 2n} is formed to compute the binary of RNS counterpart. The proposed architecture is shown to be more efficient both in terms of hardware cost and conversion delay in comparison with the related state-of-the-art works. [ABSTRACT FROM AUTHOR]

Background: It is not well known whether the distributions of variations of circle of Willis (CW) are different in different populations. Previous studies have indicated: (a) The variations of the structure of the CW in different populations and ethnic and (b) some correlation between those congenital anatomical variations and possible cerebrovascular diseases. The frequency of such anatomical variations has not been evaluated sufficiently in the Iranian population. The aim of this study is to find the variations of the anatomy of the vessels in the CW in sample population of Iranian people and compare it with other available studies in the literature, providing a new grouping for variations. Methods: Samples were obtained from 200 autopsies in different ages, all retrieved in the department of Forensic Medicine, Tehran university of Medical Sciences after achieving permission from the Department of Ethics and Medico‑legal Sciences. The CW was examined directly, using magnification, at the base of the brain. The cerebral vessels were observed for their configuration and their calibers were measured directly. Variations were noted and grouped into different categories. Results: Out of the 200 specimens examined, 69 (34.5%) were compatible with the typical anatomy of the CW. In the remaining 65.5% of the specimens, there were variations in the CW. Hypoplasia of the posterior communicating arteries was the most common variation in our study. One of the autopsies showed the presence of an aneurysm (0.5%). Conclusion: The anatomical variations found in our study were not significantly different from those reported in the literature. Based on the available data; (a) there is no evidence that the distribution of the variations of the anatomy of the CW is different in various societies and (b) the prevalence of the congenital aneurysmal changes in this region is not low in the Iranian population. [ABSTRACT FROM AUTHOR]

Background: Transsphenoidal encephaloceles represent a rare clinical entity with wide range of symptoms in adult. Such lesions require accurate diagnosis and surgical treatment. The incidence of congenital encephalocele is very low occurring in approximately 1 in 3000-5000 live births. Even though 63 similar cases have been reported in the literature not all of them have been discussed completely. Due to the rare occurrence of these lesions, we will focus on the main clues in the diagnosis and management of such lesions, which are challenging. Case Description: We intend to present our experience with two cases of trans-sphenoidal meningoencephalocels, one located medially and the other herniating through the Sternberg's canal. The younger was 17 and the elder was 47 years old and both of them presented with cerebrospinal fluid (CSF) leakage. Both patients were treated successfully using pure endoscopic endonasal approach. Conclusion: Ideal surgical approach for such patients is still not clear due to lack of adequate experience in the literature, it is suggested that full preoperative imaging studies might lead the surgeons to undertake minimally invasive skull base approaches in similar patients. [ABSTRACT FROM AUTHOR]

Background: Primary spinal primitive neuroectodermal tumors (PNET) and/ or spinal extraskeletal Ewing's sarcoma family tumors (ESET) are rare lesions appearing in the spinal extradural space. One hundred forty-one primary spinal PNETs, including 29 intramedullary lesions, have been reported in the literature. Encountering a case of primary epidural EES/peripheral PNET (pPNET) in sacral level, which is the fifth one occurring at this level in the literature, we have tried to conduct a meta-analysis of the reported cases. Case Description: A 44-year-old lady with epidural EES/pPNET is reported here. She was once operated for L5/S1 herniated disc, which did not ameliorate her symptoms. The clinical, imaging, surgical, and histopathologic characteristics of our case are presented and wide search of the literature is also done. All the reports were level 3 or less evidences and most of the series had missing parts. 106 cases of primary intraspinal (extradural/extramedullary-intradural) EES/pPNET and 29 cases of primary intramedullary PNET (CNS-PNET) have been reported in the literature. The most common clinical presentation in both entities was muscle weakness proportionate to the tumor location. Distant metastasis occurred in 38 of 99 (38%) cases of primary intraspinal EES/pPNET, while the rate of metastasis was 48% in patients with PNETs occurring in the intramedullary region (P > 0.05). One-year survival rate of the patients who underwent chemo-radiation after total or subtotal resection was better than those who did not receive chemotherapy or radiotherapy, or did not have total or subtotal resection. However, this difference was not repeated in 2-year survival rate in any of the tumor groups. Conclusion: It seems that total or subtotal removal of the tumor and adjuvant chemo- and radiation therapy can improve the outcome in these patients. [ABSTRACT FROM AUTHOR]

This paper assesses the impact of exclusive truck facilities on urban freeway performance. A large-scale regional microscopic traffic simulation model is developed for morning and afternoon peak hours and is used to model two alternative truckway configurations in the Greater Toronto Area (GTA), including a truck-only highway and a truck lane conversion on Highway 401. Demand inputs to the microsimulation model are generated by a regional transportation demand model that provides origin-destination (OD) matrices for light, medium, and heavy trucks and passenger cars. Plug-ins are developed to represent a truck-only lane in the simulation environment. The simulation model is successfully calibrated to reflect observed road counts and to produce realistic congestion patterns. The effect of infrastructure changes on travel distances, travel times, exclusive truck lane usage, and travel speeds is assessed. Microscopic simulation allows queuing formation/dissipation and bottlenecks to be represented and allows for separate analysis of truck and car performance. Addition of a 4-lane truck-only highway results in greater travel time improvements for trucks, and it sometimes results in shifting of traffic bottlenecks on Highway 401 to downstream locations. Conversion of a freeway lane on Highway 401 results in increased congestion for passenger cars, but improved travel speeds for trucks. Both scenarios show truck facility usage ranges from 100 to 800 trucks per hour per direction. [ABSTRACT FROM AUTHOR]

Background: It is almost an accepted scenario that trigeminal neuralgia (TN) occurs when there is a kind of vascular compression on the root entry zone of trigeminal nerve at pons. There are occasional reports about trigeminal neuralgia as the presenting sign of intracranial tumors but temporal glioma has rarely been included in the list. Case Description: We report three cases of temporal lobe glioma which presented with trigeminal neuralgia as the initial manifestation and review the relevant literature briefly. The patients were 19-, 20-, and 31-year-old males who presented with partially controlled TN. The tumor mass could be detected in paraclinical evaluations when the usual modalities of therapy for facial pain in our community were not effective. Excisional surgery led in full pain control in all the cases. Two of the patients died because of tumor recurrence after a year and the other one is being treated by adjuvants. Conclusion: We add these types of intracranial tumors to the list of the etiologies for TN and the possible mechanisms for the initiation of pain in these types of intracranial tumors are discussed. [ABSTRACT FROM AUTHOR]

Background/Subject: A rare case of osteoblastoma of the third cervical vertebra (C3) occurring in a 16-year-old adolescent is presented. He was admitted suffering from neck pain for more than 3 years. Method: Plain X-rays, technetium bone scanning, CT scan and MRI indicated an expansile, partially sclerotic lesion of the C3 involving the superior facet and pedicle on the right side. The lesion was excised through a posterior approach. Result: Even though the 18-month follow-up is still a very short interval in our case, the subject's neck pain has resolved completely and there has been no sign of tumor recurrence in the recently taken imaging. There has been no clinical or radiologic sign of instability in the follow-up investigations. To the best of our knowledge, this is the third case of C3 osteoblastoma reported in the literature, highlighting the predilection of the reported cases to occur in 14- to 16-year-old boys. Conclusion: A full investigation is indicated in youngsters suffering from persisting neck pain and complete resection of the lesion can prevent recurrence and malignant transformation. Long-term follow-up is needed to declare a lifelong cure of the disease. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Optic nerve glioma (ONG) originating purely from the intracranial part of the optic nerve is a very rare presentation of optic pathway gliomas. We encountered a 48-year-old woman presenting with an intra-axial lesion in preoperative magnetic resonance imaging (MRI), which turned out to be a lesion originating from the intracranial segment of the optic nerve. We intend to present the case and discuss the interesting and misleading images and the different aspects of management of this rare pathology briefly. [ABSTRACT FROM AUTHOR]

Presents a case of congenital dermoid tumor of the right cerebellopontine angle-tentorial notch region containing 12 mature teeth and 14 pseudocartilagenous structures in a six-year old boy. Shapes of calcifications; Difficulties in classifying dermoid tumors and teratomas.

Highlights from the article: There is no flow chart, and two of the mentioned keywords do not match with the MESH linked with aneurysm surgery, i.e., "commonest anterior circulation aneurysm treated by keyhole approach" and "complete occlusion rate." The incision is made within the eyebrow, it is almost always visible, and the hair loss at the margin of the incision makes the incision more visible. The most striking aspects of the approach are that the surgeon must position his patient as optimally as possible so that gravity can be used to let the frontal lobe fall by itself and that the surgeon is forced to minimize frontal lobe retraction and manipulation.

Off-peak delivery (OPD) is the delivery of goods during the evening and overnight hours. This strategy has the potential to alleviate peak period congestion, improve efficiency of delivery firms, and reduce emissions. This paper investigates benefits and challenges of a pilot OPD program in the Region of Peel, with the goal of informing potential broader implementations of OPD. In contrast to other previously implemented OPD projects, this OPD pilot focuses on deliveries in suburban areas. Three firms, delivering to 14 pilot retail stores, participated in the OPD pilot in the Region of Peel from March to August 2019. The analysis shows that during the six-month pilot, the average speed of the trips that were made in off-peak hours, from 7:00 p.m. to 7:00 a.m. the next day, is 18.1% faster than those that happened in day-time hours. Furthermore, the total greenhouse gas emissions/km decreased by 10.6%, and emissions factors for air quality pollutants, including CO, NOx, PM10, and PM2.5 reduced by 10.8% to 15.0% in off-peak hours. Results for service times varied between firms, but on average increased by 15.2%, indicating activities in the off-peak hours at the retail stores that prevented overall improvements in service time compared to day-time deliveries. A post-pilot interview was done with logistics managers of the three firms, which provides rich insights about challenges, successes, and ways that the OPD program could be improved. [ABSTRACT FROM AUTHOR]

Nonmissile low-velocity penetrating brain injuries are unusual among civilian population. Workrelated penetrating head wounds are rarer among this group. Here, we report two rare cases of penetrating head wounds caused by industrial grinder tool. The patients (both men) were struck to the head by detached blades of the grinder tool. Depressed fractures, penetrated bone fragments, and dural lacerations were all treated by the routine fashion. Paranasal sinus damage and further cerebrospinal fluid leakage were also treated conservatively. The reported cases are unexpected variants of injuries that neurosurgeons may come across and their management is still beyond the scope of textbooks. Skill and experience of the general neurosurgeons can handle the cases properly but prevention of such incidents using safer and guarded instruments should be stressed to manufacturers. [ABSTRACT FROM AUTHOR]

Reading with interest the manuscript "A single centre's experience of managing sphenoorbital meningiomas: lessons for recurrent tumour surgery" Acta Neurochirurgica 10.1007/s00701-019-03977-3 [[2]], the researchers have retrospectively analyzed the medical records of 31 consecutive patients who underwent surgery for spheno-orbital meningioma at a single tertiary center between 2005 and 2016. Seven patients had a pterional craniotomy, 19 had orbitozygomatic craniotomy, and 8 underwent a modified mini-orbitozygomatic craniotomy. The authors have come to a nice: "good clinical and cosmetic outcomes may be achieved with a smaller craniotomy and custom-made implants, irrespective of whether the operation is the patient's first procedure". [Extracted from the article]