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Background; The placenta previa (PP) is an obstetric problem in which the placental tissue is improperly located inside the lower uterine segment. Aim and objectives: was to see how effective uterine artery Doppler velocimetry was in detecting unusually morbidly adhering placentas in patients who had had one or more prior caesarean sections with placenta previa. Subjects and methods; Cross-sectional research of 100 patients was undertaken in the Department of Gynecology and Obstetrics, El- Sayed Galal Hospital, AL- Azhar University. Result; Our results showed highly statistically significant correlation between the presence of abnormal lacunae and histopathological confirmation (P-value > 0.001). In addition, the overall Sensitivity, specificity, PPV, NPV and accuracy were 90%, 100%, 100%, 64.2%, 91.6%. This criterion showed very high sensitivity and specificity with very high positive predictive value and accuracy to become the most important criteria, Conclusion; As a result of this, we conclude that the accuracy of abnormal placental lacunae, loss of the reto-placental clear zone, myometrial thinning, and utero-vesical hypervascularity are the most critical ultrasound criteria for diagnosing placenta accreta in patients who had a previous CS with a placenta previa overlying the previous uterine scar.

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Background: During the last decade, cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) was a current research focus without a standardized classification in digital subtraction angiography (DSA). This study was performed to investigate a device-independent visual cerebral vasospasm classification for endovascular treatment. Methods: The analyses are DSA based rather than multimodal. Ten defined points of intracranial arteries were measured in 45 patients suffering from cerebral vasospasm after SAH at three time points (hospitalization, before spasmolysis, control after six months). Mathematical clustering of vessel diameters was performed to generate four objective grades for comparison. Six interventional neuroradiologists in two groups scored 237 DSAs after a new visual classification (grade 0–3) developed on a segmental pattern of vessel contraction. For the second group, a threshold-based criterion was amended. Results: The raters had a reproducibility of 68.4% in the first group and 75.2% in the second group. The complementary threshold-based criterion increased the reproducibility by about 6.8%, while the rating deviated more from the mathematical clustering in all grades. Conclusions: The proposed visual classification scheme of cerebral vasospasm is suitable as a standard grading procedure for endovascular treatment. There is no advantage of a threshold-based criterion that compensates for the effort involved. Automated vessel analysis is superior to compare inter-group results in research settings.

This paper presents a hardware implementation of flexible and low-cost attitude determination and control system (ADCS) for two-axis-stabilized CubeSat. As small satellite missions are increasing, the CubeSat requires precise ADCS with attitude drift adjustment. This attitude drift if not properly compensated, will cause a slow attitude information loss as the error in attitude rises between the actual and estimated signals. The proposed ADCS comprises two steps; the attitude determination which estimates the current CubeSat’s attitude and a novel simplified intelligent proportional-integral control algorithm that accurately adjusts the attitude. The control algorithm is based on the multi degree-of-freedom controller concept and has no controller gains parameters. The proposed ADCS employs sun sensor, magnetometer, and a micro-electro-mechanical gyroscope sensor to correct the attitude drift by offering a comparative attitude that is utilized for updating the estimated attitude delivered to the Kalman filter for determining the CubeSat’s attitude and angular velocity. The ADCS model verification and validation are accomplished via Matlab/Simulink and hardware implementation. A comparison with other ADCS techniques is presented. The ADCS simulated model demonstrates precision results with error of less than 0.1°.

In this paper, a high-speed microturbine (MT) permanent magnet assisted synchronous reluctance generator (PMa-SynRG) real-time emulation based on linear impedance regulator (LIR) using power hardware-in-the-loop (PHIL) for wind energy generation tests is presented. The LIR is designed without any feedback control loop for reshaping the $s$ -domain performances of the current filter along with the converter inside the PMa-SynRG emulated system. The PHIL platform not only provides a method for eliminating the high cost of using real renewable energy hardware but also it enables the developers to create new, rapid, and reliable controllers for renewable energy testing. This platform can be used in investigating the performance of energy system under various conditions even if the generator prototype is not yet developed or unavailable. PMa-SynRG mathematical model is emulated in the real-time using PHIL platform while the output voltage of the proposed emulator imitates the generated voltage through the simulated model. In addition, a voltage source converter is employed as a voltage amplifier for imitating the PMa-SynRG performance when supplying nonlinear/linear loads. In this paper, the proportional-integral resonant (PIR) controller is utilized at the voltage control loop for tracking the distorted output reference signal voltage. In order to investigate the performance of the proposed PMa-SynRG emulator, it has been simulated and compared with MATLAB/SIMULINK environment.

Intradural extramedullary cavernoma is a very rare lesion of the spinal cord, especially of the cervical spine. Its clinical presentation can vary with symptoms of sensory or motor deficits and even with symptoms of subarachnoid hemorrhage (SAH).The authors present a case of a 45-year-old man with SAH with prolonged neck pain and increasing headache confirmed by lumbar puncture. Head computed tomography revealed only discrete blood deposits in the right frontal and biparietal lobes. The finding of pan-cerebral angiography was negative for the cause of bleeding. Spinal magnetic resonance imaging revealed an intradural extramedullary mass lesion at cervical level C5-6. The finding of subsequent cervical angiography was negative. The diagnosis of a cavernous malformation was confirmed histopathologically after surgery. The cavernoma was completely removed, and full recovery of the initial symptoms was achieved.Spinal lesions should be considered in the diagnostic work-up for SAH with excluded origin of bleeding in cranial neuroimaging. An intradural extramedullary cavernous malformation is an extremely rare entity in the differential diagnosis of SAH, and surgical resection is the treatment of choice to prevent further bleeding and neurological deficits.

OBJECTIVE Cranioplasty (CP) is a crucial procedure after decompressive craniectomy and has a significant impact on neurological improvement. Although CP is considered a standard neurosurgical procedure, inconsistent data on surgery-related complications after CP are available. To address this topic, the authors analyzed 502 patients in a prospective multicenter database (German Cranial Reconstruction Registry) with regard to early surgery-related complications. METHODS Early complications within 30 days, medical history, mortality rates, and neurological outcome at discharge according to the modified Rankin Scale (mRS) were evaluated. The primary endpoint was death or surgical revision within the first 30 days after CP. Independent factors for the occurrence of complications with or without surgical revision were identified using a logistic regression model. RESULTS Traumatic brain injury (TBI) and ischemic stroke were the most common underlying diagnoses that required CP. In 230 patients (45.8%), an autologous bone flap was utilized for CP; the most common engineered materials were titanium (80 patients [15.9%]), polyetheretherketone (57 [11.4%]), and polymethylmethacrylate (57 [11.4%]). Surgical revision was necessary in 45 patients (9.0%), and the overall mortality rate was 0.8% (4 patients). The cause of death was related to ischemia in 2 patients, diffuse intraparenchymal hemorrhage in 1 patient, and cardiac complications in 1 patient. The most frequent causes of surgical revision were epidural hematoma (40.0% of all revisions), new hydrocephalus (22.0%), and subdural hematoma (13.3%). Preoperatively increased mRS score (OR 1.46, 95% CI 1.08–1.97, p = 0.014) and American Society of Anesthesiologists Physical Status Classification System score (OR 2.89, 95% CI 1.42–5.89, p = 0.003) were independent predictors of surgical revision. Ischemic stroke, as the underlying diagnosis, was associated with a minor rate of revisions compared with TBI (OR 0.18, 95% CI 0.06–0.57, p = 0.004). CONCLUSIONS The authors have presented class II evidence–based data on surgery-related complications after CP and have identified specific preexisting risk factors. These results may provide additional guidance for optimized treatment of these patients.

In this paper, a model reference adaptive system (MRAS) based super-twisting sliding-mode-based speed observer (STSM) with direct torque control (DTC) strategy of a squirrel cage six-phase induction motor (SC6PIM) for ship propulsion application is presented. The flux estimator is based on the super-twisting (ST) approach which is a second-order SM technique. This estimator is employed as a reference model in the MRAS based-speed observer to get rid of the problem of chattering in the traditional sliding mode (SM) approaches. The STSM controller is employed at the speed, stator flux, and at the torque control loops of SC6PIM to enhance the syatem performance during external load disturbances. In addition, the STSM observer estimates the stator flux and torque with providing a robust performance without the consequences of high chattering problem. The performance of the proposed MRAS-based STSM observer is investigated experimentally for a 750 W SC6PIM and compared with conventional MRAS observer during different speed commands, and low speed command and low load torque conditions.

Molybdenum disulfide is one of the most common lubricant coatings for space systems but it displays enormous susceptibility to environmental conditions making it hard to predict performance throughout the entire lifetime. The majority of mechanisms for space operate in low Earth orbit where temperatures typically reach 120 &deg, C along with exposure to highly reactive atomic oxygen which can be detrimental to lubricant performance. In the present study, a MoS2 lubricant coating is tested using friction force microscopy under different environmental conditions including air and dry nitrogen environments with temperatures ranging from 25 &deg, C to 120 &deg, C. The increased temperature was found to be beneficial for friction behaviour in air up to 100 &deg, C as ambient humidity is removed from the contact, but higher temperatures become detrimental as increased reactivity leads to oxidation. These competing effects resulted in a minimum coefficient of friction at 110 &deg, C in the air environment. The high temperature also increases the wear of the coatings as the intrinsic shear strength decreases with thermal energy which in turn disrupts tribofilm formation leading to increased friction. The run-in duration and magnitude are both found to decrease with temperature as the energy barrier to optimal reconfiguration is reduced. Finally, contextualization of the present findings for mechanisms operating in low earth orbit is discussed.

Flow diversion (FD) is a novel endovascular technique based on the profound alteration of cerebrovascular hemodynamics, which emerged as a promising minimally invasive therapy for intracranial aneurysms. However, delayed post-procedural stroke remains an unexplained concern. A consistent follow-up-regimen has not yet been defined, but is required urgently to clarify the underlying cause of delayed ischemia. In the last two years, 223 patients were treated with six different FD devices in our center. We identified subacute, FD-induced segmental vasospasm (SV) in 36 patients as a yet unknown, delayed-type reaction potentially compromising brain perfusion to a critical level. Furthermore, 86% of all patients revealed significant SV approximately four weeks after treatment. In addition, 56% had SV with 25% stenosis, and 80% had additional neointimal hyperplasia. Only 13% exhibited SV-related high-grade stenosis. One of those suffered stroke due to prolonged SV, requiring neurocritical care and repeated intra-arterial (i.a.) biochemical angioplasty for seven days to prevent territorial infarction. Five patients suffered newly manifested, transient hemicrania accompanying a compensatorily increased ipsilateral leptomeningeal perfusion. One treated vessel obliterated permanently. Hence, FD-induced SV is a frequent vascular reaction after FD treatment, potentially causing symptomatic ischemia or even stroke, approximately one month post procedure. A specifically early follow-up-strategy must be applied to identify patients at risk for ischemia, requiring intensified monitoring and potentially anti-vasospastic treatment.

BACKGROUND: Human amniotic fluid-derived stem cells (hAF-MSCs) have a high proliferative capacity and osteogenic differentiation potential in vitro. The combination of hAF-MSCs with three-dimensional (3D) scaffold has a promising therapeutic potential in bone tissue engineering and regenerative medicine. Selection of an appropriate scaffold material has a crucial role in a cell supporting and osteoinductivity to induce new bone formation in vivo. AIM: This study aimed to investigate and evaluate the osteogenic potential of the 2nd-trimester hAF-MSCs in combination with the 3D scaffold, 30% Nano-hydroxyapatite chitosan, as a therapeutic application for bone healing in the induced tibia defect in the rabbit. SUBJECT AND METHODS: hAF-MSCs proliferation and culture expansion was done in vitro, and osteogenic differentiation characterisation was performed by Alizarin Red staining after 14 & 28 days. Expression of the surface markers of hAF-MSCs was assessed using Flow Cytometer with the following fluorescein-labelled antibodies: CD34-PE, CD73-APC, CD90-FITC, and HLA-DR-FITC. Ten rabbits were used as an animal model with an induced defect in the tibia to evaluate the therapeutic potential of osteogenic differentiation of hAF-MSCs seeded on 3D scaffold, 30% Nano-hydroxyapatite chitosan. The osteogenic differentiated hAF-MSCs/scaffold composite system applied and fitted in the defect region and non-seeded scaffold was used as control. The histopathological investigation was performed at 2, 3, & 4 weak post-transplantation and scanning electron microscope (SEM) was assessed at 2 & 4 weeks post-transplantation to evaluate the bone healing potential in the rabbit tibia defect. RESULTS: Culture and expansion of 2nd-trimester hAF-MSCs presented high proliferative and osteogenic potential in vitro. Histopathological examination for the transplanted hAF-MSCs seeded on the 3D scaffold, 30% Nano-hydroxyapatite chitosan, demonstrated new bone formation in the defect site at 2 & 3 weeks post-transplantation as compared to the control (non-seeded scaffold). Interestingly, the scaffold accelerated the osteogenic differentiation of AF-MSCs and showed complete bone healing of the defect site as compared to the control (non-seeded scaffold) at 4 weeks post-transplantation. Furthermore, the SEM analysis confirmed these findings. CONCLUSION: The combination of the 2nd-trimester hAF-MSCs and 3D scaffold, 30% Nano-hydroxyapatite chitosan, have a therapeutic perspective for large bone defect and could be used effectively in bone tissue engineering and regenerative medicine.

Lipomatosis of the nerve (LN) commonly presents with neurologic dysfunction due to massive fibro-fatty enlargement of the peripheral nerves. It is uniquely associated with adipose proliferation in the subcutaneous tissue and muscle in the innervated territory, along with osseous abnormalities. Herein, we present the case of a 56-year-old woman who presented with severe right ulnar distribution pain involving the medial forearm and hand (9/10 on a numerical rating scale), declining right-hand strength, movement-dependent hypoesthesias, paresthesias, and a pronounced claw deformity of the right hand with intrinsic atrophy. Electrodiagnostic studies demonstrated pronounced fibrillations, decreased voluntary activation, and minimal collateral reinnervation in the abductor digiti minimi and abductor pollicis brevis, consistent with dysfunction of the lower trunk of the right brachial plexus. Magnetic resonance imaging (MRI) and computed tomography (CT) of the brachial plexus were interpreted as a tumor on the right supra- and infraclavicular brachial plexus. At surgery, the brachial plexus was embedded in relatively tight connective tissue with a typical lipoma posteriorly. The lipoma was resected, and the plexus was explored extensively. This case is the 10th report of LN involving the brachial plexus and demonstrated the cardinal features of LN. It provides insight into the pattern of lesions associated with innervation by LN.

BACKGROUND: Cell therapies offer a promising potential in promoting bone regeneration. Stem cell therapy presents attractive care modality in treating degenerative conditions or tissue injuries. The rationale behind this is both the expansion potential of stem cells into a large cell population size and its differentiation abilities into a wide variety of tissue types, when given the proper stimuli. A progenitor stem cell is a promising source of cell therapy in regenerative medicine and bone tissue engineering. AIM: This study aimed to compare the osteogenic differentiation and regenerative potentials of human mesenchymal stem cells derived from human bone marrow (hBM-MSCs) or amniotic fluid (hAF-MSCs), both in vitro and in vivo studies. SUBJECTS AND METHODS: Human MSCs, used in this study, were successfully isolated from two human sources; the bone marrow (BM) and amniotic fluid (AF) collected at the gestational ages of second or third trimesters. RESULTS: The stem cells derived from amniotic fluid seemed to be the most promising type of progenitor cells for clinical applications. In a pre-clinical experiment, attempting to explore the therapeutic application of MSCs in bone regeneration, Rat lumbar spines defects were surgically created and treated with undifferentiated and osteogenically differentiated MSCs, derived from BM and second trimester AF. Cells were loaded on gel-foam scaffolds, inserted and fixed in the area of the surgical defect. X-Ray radiography follows up, and histopathological analysis was done three-four months post- operation. The transplantation of AF-MSCs or BM-MSCs into induced bony defects showed promising results. The AF-MSCs are offering a better healing effect increasing the likelihood of achieving successful spinal fusion. Some bone changes were observed in rats transplanted with osteoblasts differentiated cells but not in rats transplanted with undifferentiated MSCs. Longer observational periods are required to evaluate a true bone formation. The findings of this study suggested that the different sources; hBM-MSCs or hAF-MSCs exhibited remarkably different signature regarding the cell morphology, proliferation capacity and osteogenic differentiation potential CONCLUSIONS: AF-MSCs have a better performance in vivo bone healing than that of BM-MSCs. Hence, AF derived MSCs is highly recommended as an alternative source to BM-MSCs in bone regeneration and spine fusion surgeries. Moreover, the usage of gel-foam as a scaffold proved as an efficient cell carrier that showed bio-compatibility with cells, bio-degradability and osteoinductivity in vivo.

This paper presents the real-time validation of micro-satellite (MS) attitude determination and control system (ADCS) using modified proportional-integral (MPI) attitude control on the hardware-in-the-loop (HIL) platform. This platform eliminates the high costs of using real hardware in attitude control of satellite system and enables researchers to develop new, rapid, and reliable controllers in space tests. Due to the increasing demands for using small satellites in space, MS requires accurate ADCS and attitude drift regulation. In case the non-proper compensation of the attitude drift, thus, attitude information will be lost as the attitude error will be rise between actual along with estimated signals. MS's attitude is determined by estimating its current attitude and the attitude control is performed via using MPI attitude controller which can precisely correct the MS's attitude. This controller has simple design without controller gains parameters. ADCS emulated model has accuracy results with attitude error approximately 0.01 degree.

Cubesat is a nano-satellite system standard, where a nano-satellite has structure, power, telemetry, payload among other subsystems, however, it fits up to 1.3 kilograms and 10cm×10cm×10cm modules [1]. Nano-satellites present flexibility in design; in recent years there are several proposals on how to implement the subsystems. The resolution continued to improve, which in turn lead to the need for higher accuracy pointing. They push the bounds of small size and low cost developed to provide cheap access to space and used primarily by universities, these satellites are measured in the tens of centimeters, weigh between one and ten kilograms, and usually cost in the tens of thousands of dollars.

The neuropathology following traumatic brain injury (TBI) is poorly understood. From the primary biomechanical injury, secondary injuries develop, including neuro-inflammatory processes. These secondary injuries are regarded as a potential targets for treatment and diagnostics. The translocator protein 18 kDa (TSPO) is robustly upregulated in response to brain injury, making it a suitable biomarker for glia activation and the neuro-inflammatory response. Second-generation radioligands of TSPO, such as [123I]CLINDE, offer higher affinity and signal-to-noise ratio compared to PK11195, the prototypical ligand. Applicability of [123I]CLINDE was demonstrated in both neurodegenerative disease models and patient studies and therefore demonstrate the translational value of this tracer. We therefore investigated TSPO expression in a rat model of TBI with [123I]CLINDE , a selective and clinically relevant TSPO-radioligand. Adult Sprague-Dawley rats were subjected to moderate Controlled-Cortical-Impact injury (CCI, n=5 per group). Sham (n=5), craniotomy (n=3), and naïve animals (n=3) served as different control groups. Animals were sacrificed at 6h, 24h, 72h, and 28 days post-surgery, and TSPO expression was assessed in brain section employing [123I]CLINDE in vitro autoradiography. From 24 h to 28 d post-surgery, injured animals exhibited a marked and time-dependent increase of binding in the ipsilateral motor, somatosensory and parietal cortex, as well as in the hippocampus and thalamus. Furthermore, binding was significantly elevated in the contralateral motor cortex following TBI. Craniotomy also caused a significant increase in [123I]CLINDE binding per se. Radioligand binding was consistent with an increase in TSPO mRNA expression and OX-42 immunoreactivity at the contusion site. In conclusion, this study demonstrates the applicability of [123I]CLINDE for brain regional and quantitative assessment of neuro-inflammatory activity in experimental models of TBI.

β-Catenin stabilization achieved either via GSK-3β specific inhibition or involving canonical Wnt signalling pathway, contributes to neuroprotection in an oxygen-glucose deprivation (4h OGD) in vitro hypoxia model performed on human cortical neural progenitor cells previously differentiated into neurons and glia. Neuroprotection mechanisms include both acquiring tolerance to injury throughout preconditioning (72 h prior to OGD) or being pro-survival during 24h reoxygenation after the insult. Four hours of OGD induced apoptotic cell death elevation to 73 ± 1% vs. 12% measured in control and the LDH level, indicative of necrotic cell injury, elevation by 67 ± 7% (set to 100%). A significant reduction in apoptosis occurred at 24h reoxygenation with indirubin supplement which was 49 ± 6% at 2.5 μM BIO while LDH level was only 47 ± 5% of OGD. Kenpaullone was efficient in reducing both cell deaths at 5 μM (apoptosis 38 ± 1% and necrosis 33 ± 3% less than in OGD). Wnt agonist reduced apoptosis to 45 ± 3% at 0.01 μM, while LDH value was decreased to a level of 53 ± 5% of control. Our findings suggest that GSK-3beta inhibitors/β-catenin stabilizers may ultimately be useful drugs in neuroprotection and neuroregeneration therapies in vivo.

Experimental human fetal neural progenitor cell (hfNPC) transplantation has proven to be a promising therapeutic approach after traumatic brain injury (TBI). However the long-term efficacy and safety, which are both highly important for clinical translation of this approach, have not been investigated so far. This study investigated the effect of local (1x105 cells) (L) and systemic (5x105 cells) (S) administration of PKH-26-labeled pre-differentiated hfNPCs over a period of twelve weeks, twenty-four hours after severe controlled cortical impact TBI in Sprague-Dawley rats. Accelerating rotarod testing revealed a trend of functional improvement beginning one week after transplantation and persisting until the end of the experiment. The traumatic lesion volume as quantified by magnetic resonance imaging was smaller in both treatment groups when compared to control (C) animals (C = 54.50 mm3, L = 32 mm3, S = 37.50 mm3). Correspondingly, NeuN staining showed increased neuronal survival at the border of the lesion in both transplanted groups (S: 92.4%; L: 87.2%; 72.5%). Histological analysis of brain compartments revealed transiently increased angiogenesis and reduced astroglial reaction during the first four weeks post-transplantation. PKH-26-positive cells were detected exclusively after local transplantation without any evidence of tumor formation. However, graft differentiation was only observed in very rare cases. In conclusion, transplantation of hfNPCs improved the long-term functional outcome after TBI, diminished trauma lesion size and increased neuronal survival in the border zone of the lesion. This therapeutic effect was most unlikely due to cell replacement but was associated with transiently increased angiogenesis and reduced astrogliosis.

Background: Numerous studies have reported a beneficial impact of neural progenitor cell transplantation on functional outcome after traumatic brain injury (TBI) during short and medium follow-up periods. However, our knowledge regarding long-term functional effects is fragmentary while a direct comparison between local and systemic transplantation is missing so far. Objectives: This study investigated the long-term (12 week) impact of human fetal neuronal progenitor cell (hNPC) transplantation 24 h after severe TBI in rats. Methods: Cells were either transplanted stereotactically (1 × 105) into the putamen or systemically (5 × 105) via the tail vein. Control animals received intravenous transplantation of vehicle solution. Results: An overall functional benefit was observed after systemic, but not local hNPC transplantation by area under the curve analysis (p < 0.01). Surprisingly, this effect vanished during later stages after TBI with all groups exhibiting comparable functional outcomes 84 days after TBI. Investigation of cell-mediated inflammatory processes revealed increasing microglial activation and macrophage presence during these stages, which was statistically significant after systemic cell administration (p < 0.05). Intracerebral hNPC transplantation slightly diminished astrogliosis in perilesional areas (p < 0.01), but did not translate into a permanent functional benefit. No significant effects on angiogenesis were observed among the groups. Conclusion: Our results suggest the careful long-term assessment of cell therapies for TBI, as well as to identify potential long-term detrimental effects of such therapies before moving on to clinical trials. Moreover, immunosuppressive protocols, though widely used, should be rigorously assessed for their applicability in the respective setup.