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BACKGROUND Radical resection of gastric cancer liver metastases (GCLM) can increase the 5-year survival rate of GCLM patients. However, patients may lose the theoretical feasibility of surgery due to the critical location of liver metastasis in some cases. CASE SUMMARY A 29-year-old woman had a chief complaint of chronic abdominal pain for 1 year. Abdominal computed tomography and magnetic resonance imaging examinations suggested a mass of unknown pathological nature located between the first and second hila and the margin of the lower segment of the right lobe of the liver. The anterior wall of the gastric antrum was unevenly thickened. The diagnosis of (gastric antrum) intramucosal well-differentiated adenocarcinoma was histopathologically confirmed by puncture biopsy with gastroscopy guidance. She underwent radical resection (excision of both gastric tumors and ex vivo liver resection followed by autotransplantation simultaneously) followed by XELOX adjuvant chemotherapy. Without serious postoperative complications, the patient was successfully discharged on the 20th day after the operation. Pathological examination of the excised specimen indicated that gastrectomy with D2 lymph node dissection for primary gastric tumors and R0 resection for liver metastases were achieved. The resected mass was confirmed to be poorly differentiated gastric carcinoma (hepatoid adenocarcinoma with neuroendocrine differentiation) with liver metastases in segments VIII. No recurrence or metastasis within the liver was found during a 7.5-year follow-up review that began 1 mo after surgery. CONCLUSION Application of ex vivo liver resection followed by autotransplantation in radical resection for GCLM can help selected patients with intrahepatic metastases located in complex sites obtain a favorable clinical outcome.

Tomasz Czernicki Department of Neurosurgery, Medical University of Warsaw, Warsaw, PolandCorrespondence: Tomasz CzernickiDepartment of Neurosurgery, Medical University of Warsaw, Banacha Street 1A, Warsaw 02-097, PolandTel +48225992575Fax +48225991574Email tczernicki@wp.plPurpose: In view of the risk associated with the surgical treatment of intracranial meningiomas in the elderly population due to the physiology of aging and multiple comorbidities, an attempt was made to identify factors influencing outcomes and to define the subgroup of patients who should not be operated on due to poor results.Patients and Methods: A retrospective analysis of 58 patients over 70 years old with assessment of short-term and long-term outcomes. Scores by previously described CRGS, SKALE, and GSS grading systems were also calculated for our patients.Results: Neurological morbidity was only associated with a critical location according to the SKALE grading system (P=0.02). Six patients (10.3%) died. Mortality was associated with the Karnofsky Performance Scale score (KPS ≤ 60 vsKPS ≥ 70; P=0.0162), the American Society of Anesthesiologists scale status (ASA 1 or 2 vs ASA 3; P=0.0022) and the WHO grade of meningiomas (P=0.012). Risk factors for tumor recurrence (six patients) were WHO grade (P=0.00048) and Simpson grade of resection (P=0.0437). At follow-up, excluding patients who died due to surgery or recurrence (15.5%), most patients improved (50%) or remained unchanged (25.9%) in relation to the preoperative KPS status.Conclusion: Postoperative neurological deterioration was only associated with a critical tumor location (skull base, eloquent area, large vessels involvement by the tumor). Due to a significantly higher risk of death, careful consideration should be taken for surgery in patients in a poor functional condition (KPS ≤ 60) or in a poor physical condition (ASA 3 status). An improvement or at least nonworsening of the neurological status in relation to the preoperative condition was observed in the majority of patients during follow-up.Keywords: intracranial meningioma, elderly, brain surgery, prognostic factors, complications, recurrence, survival

Atlantoaxial chordomas being quite uncommon pose a significant therapeutic challenge to the surgeon due to their critical location and often late presentation. Recurrences are common after intralesional excision. Although en bloc excision is the preferred treatment, it may not be feasible due to anatomical constraints in this location. Hence, multimodality treatment in the form of surgery (maximal tumor excision) followed by targeted chemotherapy and radiotherapy is considered to be the next best treatment option. We present the case of a young male patient with C2 chordoma treated at our institution by multimodality approach, and follow-up for 21 months after surgery.

Accurate modelling of intracellular calcium ion ( $$Ca^{2+}$$ ) concentration evolution is valuable as it is known to rapidly increase during a Traumatic Brain Injury. In the work presented here, our older non-spatial model dealing with the effect of mechanical stress upon the $$Ca^{2+}$$ transportation in a neuron is spatialized by considering the brain tissue as a solid continuum with the $$Ca^{2+}$$ activity occurring at every material point. Starting with one-dimensional representation, the brain tissue geometry is progressively made realistic and under the action of pressure or kinematic impulses, the effect of dimensionality and material behaviour on the correlation between the stress and concomitant $$Ca^{2+}$$ concentration is investigated. The spatial calcium kinetics model faithfully captures the experimental observations concerning the $$Ca^{2+}$$ concentration, load rate, magnitude and duration and most importantly shows that the critical location for primary injury may not be the most important location as far as secondary injury is concerned.

With the ubiquitous use of mobile devices, location-based services (LBS) have rapidly pervaded daily life. By providing context- and location-specific information, LBS enable a myriad of opportunities for individuals and organizations. However, the manifold advantages come along with a radical increase in location privacy concerns and non-transparent data flows between the various actors involved. While research often focuses on protecting the dyadic relation between the user and LBS provider, the entirety of dark sides constituting privacy violations remains hidden. In this paper, we follow the paradigm of architectural thinking to shed light on the diverse dark sides emerging in today’s LBS. By drawing on a multiple case study and developing a notation for architectural maps that help understand LBS from a socio-technical and privacy-oriented perspective, we reveal six dark side archetypes of LBS.

Background: Paraganglioma of the organ of Zuckerkandl (OZ) is a rare surgically challenging tumor because of its critical location and the nature of catecholamine secretion. We describe the technique of laparoscopic excision as well as provide a literature review to confirm its feasibility. Case Presentation: In a 23-year-old male patient, laparoscopic excision of a 5 × 4 cm tumor located at the aortic bifurcation and indenting the vertebral column was performed. Preoperatively, the patient received α- and β-adrenergic blockers as well as underwent sperm banking. The patient was put in the lateral position, five ports were used: four in the midline and one in the left iliac fossa. The tumor was approached by the reflection of the colon. Ureter, gonadal vein, and sympathetic chain were preserved. Dissection of the tumor from the inferior mesenteric artery was done followed by control of three feeding arteries and two draining veins posteriorly and inferiorly. The procedure was completed laparoscopically with minimal blood loss. Intraoperatively, three episodes of hypertension developed and required stoppage and the administration of vasodilators. The patient recovered on the second day postoperatively and all antihypertensive medications were stopped. At 1 year of follow-up, the patient is tumor-free but developed anejaculation for which he is under current treatment. Conclusion: Laparoscopic excision of paraganglioma located at the OZ is safe and feasible.

Tires are the complex composite product of filled-rubber, steel, and fiber cords, made of as many as 20 components. Filled-rubber used for each component has a different formulation, characteristic, and physical property. Each component of tire is designed to have a set of properties to perform a unique functionality. These different components of tire are adhered together by chemical bonding, van der Waals force, or electrostatic attraction. During the motion of the tire, each rubber component is under continuous fatigue loading, which may cause failure at some critical location in the tire. This research study mainly focuses on establishing the experimental framework for failure in rubber components due to crack generation. An experimental study was carried out on machine fatigue to failure testing (FTFT) for evaluating the life of rubber samples. Further surfaces of failed samples have been studied and compared through advanced microscopy.

Damage in gas turbine engines can accumulate from multiple damage mechanisms including creep, fatigue, and oxidation. Each damage mechanism is influenced by various parameters which typically occur during different portions of engine operation. For instance, fatigue is influenced by large stress/strain ranges that occur during startup and shutdown transient conditions while creep is affected by sustained stress and temperature at dwell conditions. In some cases, the maximum damage location for one mechanism could experience negligible contribution in damage from any other mechanism, but in most cases, there is some degree of influence from two or three mechanisms. In those instances, damage will accumulate at various rates during separate portions of operation under different damage mechanisms. Since some applications require engines to dwell for long periods of time while other applications favor more frequent cycling, every engine will accumulate damage differently at each location. Therefore, it is difficult to estimate which location is critical to durability, rendering it necessary to capture all possible critical locations so that damage can be estimated for each application. This paper suggests a method by which to visualize and select critical locations based on all possible customer use scenarios. Once critical locations are identified, a Reduced Order Model (ROM) can be generated for each point of interest and damage can be estimated and monitored using data collection. Damage mechanisms can be combined if micromechanistic affects are additive, the material response compounds, or the material properties evolve with time. Examples of each case are demonstrated. In addition, the visual representation of damage interaction allows for uncertainty to be visualized and implemented to rank location criticality.

A novel multi-axial energy-based approach is presented and used to demonstrate the influence of different finite element (FE) modelling techniques on the prediction of the fatigue life of a rubber composite with long oriented fibres. It is shown that the simplest modelling methods using 2D elements with rebar layers, layered 2D elements or layered 3D elements do not allow for a precise determination of the critical location and damage value. In contrast, modelling methods with 3D matrix and discrete reinforcement provide much better results. The predicted critical location corresponds to the measured one, although the predicted fatigue life still differs from the measured results. The most complex microscopic modelling method shows the best agreement between the predicted and measured fatigue life. Since microscopic modelling is not suitable for modelling larger products made of rubber fibre composite, it is also noted that modelling techniques with 3D matrix and discrete reinforcing elements can be used with the same accuracy if the fatigue life curve is obtained from measurements on the specimens made of composite material rather than the specimens made of the critical base material (rubber).

Background Posterior fossa brain tumours are one of the most devastating forms of human illnesses which are more common in children. Brainstem compression, herniation and death are the risks with tumours in this critical location. Objective To evaluate our results, complications and outcome of posterior fossa tumour surgery in Benha University Hospital. Patients and methods A prospective study including 44 patients with posterior fossa tumours were performed at the Neurosurgery Department in Benha University Hospital between the period of March 2015 and October 2018. In each case, diagnosis was made clinically and confirmed radiologically and histo-pathologically. Results Out of 44 patients, 28 (63.6%) patients were males and 16 (36.4%) were females. The mean age was 17.5 + 14.2 years (ranged 2–30 years). This study showed that excellent surgical outcome was observed in 12 cases (27.3%), good in 22 cases (50%) while poor outcome was observed in 10 cases (22.7%). The best outcome is astrocytoma then ependymoma while the worst outcome is metastatic then medulloblastoma which is statistically insignificant. Conclusion The surgical treatment of posterior fossa tumours still represents a challenge for neurosurgeons. Our Benha experience shows the accepted results, complications and surgical outcome in relation to previous clinical studies. Trial registration IRB#3747. Registered 18 September 2018.

In high-pressure die casting component, shrinkage defects plays a major role in leakage of fluid from components; therefore, it becomes necessary to predict the exact location of the shrinkage defect to reduce its intensity to an acceptable level. Nowadays, a localized squeezing process is one of the popular ways of reducing the shrinkage defect in high-pressure die casting components. Squeeze pins can be used to compensate for shrinkage defects in these components. The main reason for the formation of shrinkage porosity at the critical location of a given component is large and poorly fed hot spot. In this paper, shrinkage defects are reduced from level III to level I by determining optimum values of squeeze pin parameters by DOE and flow simulation, obtained results are implemented in order to test and verify effectiveness of the method. An excellent agreement is indicated for the simulation result and the experimental results.

Primary hepatic functional paraganglioma is a rare form of extra-adrenal catecholamine-secreting tumor. Definitive treatment of functioning paraganglioma is challenging because of the critical location of the tumor frequently in close proximity to vital structures and risk of excessive catecholamine release during operative manipulation. We report the multidisciplinary management approach for a case of unresectable primary hepatic functional paraganglioma with invasion into the hepatic veins and suprahepatic vena cava. To our knowledge, this is the first report showing that orthotopic liver transplantation is curative for patients with unresectable primary hepatic paraganglioma. For locally advanced unresectable hepatic paraganglioma that involves the intrapericardial vena cava, a meticulous pre- and intraoperative medical management and transabdominal intrapericardial vascular control of the suprahepatic vena cava during orthotopic liver transplantation allows for complete extirpation of the tumor and achieves optimal outcome.

Purpose Bedside examination of premature infants at risk for retinopathy of prematurity (ROP) is performed predominantly with ophthalmoscopic en face viewing of the retina. Although postmortem retinal microstructures have been studied at the vascular–avascular junction, a critical location for pathogenesis of ROP, to date this has not been possible in vivo. Herein we present bedside, nonsedated in vivo cross-sectional imaging and analysis of retinal microstructures at the vascular–avascular junction in infants with ROP using handheld spectral-domain (SD) OCT. Design Prospective observational study. Participants Eleven preterm infants whose parents or guardians gave consent for research imaging during ROP screening examinations. Methods We imaged the vascular–avascular junction in the temporal retina using an SD OCT system (Envisu; Bioptigen, Inc., Research Triangle Park, NC) in 18 eyes from 11 preterm infants with zone I or II and stage 0 through 4 ROP. B-scan and en face images were analyzed and compared with historical light micrographs. Main Outcome Measures Spectral-domain OCT morphologic features at the vascular–avascular junction. Results Multiple bedside SD OCT findings at the vascular–avascular junction were comparable with historic light micrographs. Thickened inner retinal ridge structure in stage 2 ROP was comparable with thickened vanguard and rear guard cells visible on micrographs; vascular tufts on the posterior retinal surface in stage 2 ROP, broad arcs of neovascularization above the retina in stage 3 ROP, and splitting of inner retinal layers into clefts on either side of neovascularization mimicked findings on historic light micrographs. A unique finding was thickening of the avascular inner retinal band adjacent to neovascularization. On SD OCT imaging over several weeks, neovascularization and retinal clefts diminished after intravitreal bevacizumab therapy. Conclusions Retinal morphologic features at the vascular–avascular junction imaged with handheld SD OCT are consistent with known histopathologic features and provide the advantage of monitoring change in vivo over time. These unique findings provide new insights into preterm retinal neurovascular development in ROP.

Tumors of parapharyngeal space are difficult to access for clinical examination, due to critical location of this anatomic area. Most of these tumors are benign. Hemangiopericytomas arising in parapharyngeal space are extremely rare tumors and they have uncertain malignant potential. Radical excision of tumor is the treatment of choice. Here we report a case of young adult male patient who presented with very nonspecific throat symptom and on clinical and radiologic evaluation diagnosis of pre-styloid parapharyngeal space tumor was made and post-surgical histopatholology report showed hemangiopericytoma (solitary fibrous tumor).

Purpose The purpose of this study is to analyze the crowd dynamics of the visitors at Al-Masjid al-Nabawi during the most oversaturated period to characterize the most critical conditions and suggest technical solutions to accommodate visitors and provide them safe passage. Design/methodology/approach In this study, the time of entrance from the Al-Salam Gate to the tomb and from the tomb to the exit from the Al-Baqi’ Gate has been collected in the most oversaturated period. To be precise and to model the worst case, important crowd measures of effectiveness data are collected in the two holiest times considered by Muslims, during the holy month of Ramadan and the month of Dhul-Hijjah and during the busiest hours of the day to consider safety factors while proposing future solutions. The conventional manual head-counting method has been adopted to determine the crowd density and to carry out actual counting of the visitors from the recorded videos and photos captured by the legitimate authority. Findings The analyses revealed that the crowd dynamics in the month of Ramadan (peak) are statistically different from those for other times (off peak). In general, the crowd dynamics at all times on days other than Ramadan are almost identical. Originality/value The results of crowd characterization from this study are expected to help optimize crowd management in the Masjid at the most critical location and time. The data collected in this study could be used for future research to simulate similar crowd scenes or for even different crowd management scenarios in case of emergencies such as fire hazards or evacuation process.

Perihilar cholangiocarcinoma (Klatskin tumor) is one of the most challenging hepatobiliary cancers to treat due to its critical location and tendency to involve nearby vascular structures in the portal hepatic. A combined biliary and major liver resection is often required to achieve a complete oncological resection. Traditionally, Klatskin tumor resection is performed using an "open" approach until recently when the minimally invasive technique becomes popular due to its proven advantages. The laparoscopic technique had been reported; however, the majority of resections were types I and II without the need for ipsilateral hepatectomy. Inherent limitations of straight laparoscopic instruments result in significant technical difficulties in performing precise tissue dissection and vessel repair and creating a fine bilioenteric anastomosis. In this didactical video, we described our technique of type IIIB Klatskin tumor (B3-L perihilar cholangiocarcinoma) resection utilizing a robotic technology. The use of a robotic platform facilitates precise porta hepatic dissection, bleeding control, and creation of a fine bilioenteric anastomosis at the level of the hilar plate. We believe that the robotic platform provides an alternative method for resection of perihilar cholangiocarcinoma with excellent short-term outcomes.

To increase fuel efficiency and reduce emission, aluminium alloys have been increasingly used in automotive body-in-white structures for lightweighting. Due to its advantages over some of the more traditional joining technologies, self-piercing riveting (SPR) has been widely used for these lightweight structures. Research has showed that friction is a very important factor that influences both the riveting process and joint strength for SPR, but these influences have not been fully understood. In this paper, an innovative method was used to modify the local surface of the top sheet around the rivet piercing location with different impression tools (the central pin, the small ring, the medium ring and the large ring) and garnet particles to study the influence of local frictions on rivet inserting process, joint features and static lap shear strength. The results showed that the local surface textures on the aluminium sheet did not have significant influence on the rivet inserting process based on displacement-force curve analysis. The local surface textures could slightly change the joint features, especially the rivet head height, but overall this influence was not significant. The lap shear tests showed that ring impressions with garnet particles and central pin impressions on the bottom surface of the top sheet increased the static lap shear strength of the SPR joints. The results confirmed that the critical location for local friction influence on the lap shear strength was around the rivet leg piercing location.

Many engineering structures are exposed to non-proportional fatigue loading. However, at the critical location of crack initiation, often only one of the load sequences dominates – the individual load cases result in different crack initiation sites. Based on engineering judgment a simplified local uniaxial or proportional loading situation may be assessed. In general, the critical location must be identified by calculating fatigue lives for a variety of locations. The position of the critical location depends on the hypothesis applied for life calculation – besides loading, geometry, material and many other influence factors. For sharp three-dimensional notches the region for the search of the critical location may be restricted considerably. Weld start and stop points are an industrial example for such sharp notches. They are the object of the present investigation. They are exposed to nominal normal and shear loading. The individual hot spots for crack initiation lie necessarily close together. A strong interaction of the loading cases for both proportional and non-proportional loading was experimentally observed. In the numerical investigation notch stresses were calculated using an idealised weld end model. Based on the critical plane approach according to Findley, numerical interaction lines were produced.

Quadrigeminal arachnoid cysts (QAC) are usually accompanied by a symptomatic obstructive hydrocephalus. Several endoscopic and surgical treatments exist; however, the critical location of these cysts further complicates treatment and usually more than one procedure is required. In this report, a 31 year old female with QAC and associated obstructive hydrocephalus was successfully treated with stereotactic placement of a permanent ventricular - cystic stent (intraventricualr - cystic catheterization) in single - session. Intraventricular - cystic stenting provides a long lasting communication between these two compartments, allowing persistent "physiologic" solution to this challenging condition.

Various types of responses have been selected in the past as the driving forces of the top-down cracking. However, the most appropriate candidate for top-down cracking is the horizontal tensile strain at the pavement surface, considering the horizontal tensile strain at the bottom of asphalt layer has been historically used as the critical response for bottom-up cracking in the ME design. In this study, the mechanisms of top-down cracking are investigated based on the horizontal tensile strain at the surface. A multi-layered elastic computer code, APRA, was utilized to compute the horizontal strains at the pavement surface. APRA uses the Lucas algorithm and integration, summation and extrapolation methods to accurately determine the surface responses. The results show that traffic loading may induce significant horizontal tensile strain in the transverse direction at the surface, which is a major cause of the top-down cracking. The critical location of the tensile strain is just outside the tyre edges. It...

In this work, initiation and growth of pre-embedded delamination in the adhesive-bonded lap shear joint (LSJ) made out of laminated fibre-reinforced polymer (FRP) considering flat geometry subjected to transverse load have been investigated. 3D nonlinear finite element technique has been employed to monitor the damage mechanism. The critical location to place the delamination has been obtained from the Tsai-Wu failure criterion. It is found to occur between the first and second layers of the bottom adherend of the Lap shear joint. Proper contact elements have been employed to avoid any interpenetration of delaminated surfaces. Interlaminar peel and shear stresses are obtained and found to be three dimensional in behavior. Virtual crack closure technique (VCCT) is used to determine the three components of strain energy release rates (SERR) with respect to sliding (Mode I), opening (Mode II) and cross sliding (Mode III) modes of failure. These values are found to be different along two delamination fronts which show the dissimilar nature of propagation of delamination.

In the present paper, fatigue life of a steel box girder bridge has been evaluated by two approaches and the influencing parameters on fatigue life have been studied. In the first approach, the box girder bridge has been idealized as a Euler–Bernoulli beam and the coupled bridge–vehicle equations are developed. In the second approach, vehicle equations are first solved taking bridge as rigid. The pavement force found from the vehicle response and road roughness has been given as input in 3-D FEM model created in CSI Bridge. Fatigue life of the bridge component at the critical location has been found out using Miner approach and the stress time history from coupled and uncoupled schemes has been used for comparison purpose. The parameters which affect the fatigue life, i.e., velocity of the vehicle and road surface roughness are varied to observe the effect on fatigue life.

When remembering an object at a given location, participants tend to return their gaze to that location even after the object has disappeared, known as Looking-at-Nothing (LAN). However, it is unclear whether LAN is associated with better memory performance. Previous studies reporting beneficial effects of LAN have often not systematically manipulated or assessed eye movements. We asked 20 participants to remember the location and identity of eight objects arranged in a circle, shown for 5 s. Participants were prompted to judge whether a location statement (e.g., “Star Right”) was correct or incorrect, or referred to a previously unseen object. During memory retrieval, participants either fixated in the screen center or were free to move their eyes. Results reveal no difference in memory accuracy and response time between free-viewing and fixation while a LAN effect was found for saccades during free viewing, but not for microsaccades during fixation. Memory performance was better in those free-viewing trials in which participants made a saccade to the critical location, and scaled with saccade accuracy. These results indicate that saccade kinematics might be related to both memory performance and memory retrieval processes, but the strength of their link would differ between individuals and task demands.

Early endosomes, also called sorting endosomes, are known to mature into late endosomes via the Rab5-mediated endolysosomal trafficking pathway. Thus, early endosome existence is thought to be maintained by the continual fusion of transport vesicles from the plasma membrane and the trans-Golgi network (TGN). Here we show instead that endocytosis is dispensable and post-Golgi vesicle transport is crucial for the formation of endosomes and the subsequent endolysosomal traffic regulated by yeast Rab5 Vps21p. Fittingly, all three proteins required for endosomal nucleotide exchange on Vps21p are first recruited to the TGN before transport to the endosome, namely the GEF Vps9p and the epsin-related adaptors Ent3/5p. The TGN recruitment of these components is distinctly controlled, with Vps9p appearing to require the Arf1p GTPase, and the Rab11s, Ypt31p/32p. These results provide a different view of endosome formation and identify the TGN as a critical location for regulating progress through the endolysosomal trafficking pathway., Makoto Nagano et al show that in budding yeast, endosome formation requires vesicle transport from the Golgi. They find that endocytic internalisation is not needed for activation of the key early endosome regulator Rab5, but instead this involves the recruitment of the Rab5 GEF Vps9p to the trans-Golgi network and its subsequent shuttling to the endosome.

Scatter of structural fatigue life is mainly caused by the variability in structures and load-time histories. To study the scatter of structural load-time history of aircrafts in a fleet, this research is focused on analysis of operational load spectra at four typical structure details, of which representative coupon fatigue tests have been carried out. First, operational load-time histories at critical locations in question of each aircraft are obtained according to the flight-data based load equation and transfer function relating the monitored load to the critical location stresses. Then, the fatigue notch coefficient in local stress-strain method is calibrated and validated by representative coupon test data and then used to calculate fatigue damage under different structural load-time histories of each aircraft. Finally, statistical analysis of the fatigue damages is conducted on the assumption of log-normal distribution and scatter factor are obtained. It has indicated that there are significant differences in the scatter factor of different structural load-time histories. It may be advisable to fully consider the differences of scatter factor among different structures in structure fatigue life assessment.

With the proliferation of location-aware devices, trajectory data have been widely collected, published, and analyzed in real-life applications. However, published trajectory data often contain sensitive attributes, so an attacker who can identify an individual from such data through record linkage, attribute linkage, or similarity attacks can gain sensitive information about this individual. To resist from these attacks, we propose a scheme called Data Privacy Preservation with Perturbation (DPPP). To protect the privacy of sensitive information, we first determine those critical location sequences that can identify specific individuals. Then we perturb these sequences by adding or deleting some moving points while ensuring the published data satisfy (l, α, β)-privacy, an enhanced privacy model from ldiversity. Our experiments on both synthetic and real-life datasets suggest that DPPP achieves better privacy while still ensuring high utility, compared with existing privacy preservation schemes on trajectory.

The present work is dedicated to the analytic analysis of the non-similar wall jet flows subject to various suction/injection profiles for the 1st time. To this end, it is employed regular perturbation technique to expand the solution about the Glauert origin. We have propagated the perturbed field up to the 15th order to identify the compatibility of the technique with the problem of interest as well as to explore some important features associated with the various suction/injection profiles. In the case of suction, the maximum normalized shear stress at the wall evolves as the exponent of the suction profiles varies; afterwards, a decrease in the quantity is expected so as to eventually annihilate the entire jet. Similarly, in the injection case, the exponent of the injection profiles plays a core role in the evolution of the normalized shear stress at the wall, the universal distance in which the quantity becomes zero and the recovery of the quantity after this critical location.

The introduction of Global Positioning Systems (GPS) to the public has provided millions of people with navigation and positioning services around the globe. However, it is known that no matter the improvements to accuracy, fundamentally, GPS cannot provide location information in extreme environments, such as underwater and underground. Hence, there is a growing need for alternative technologies and methodologies of providing localization in such extreme or GPS-less environments. This paper introduces a low-power and low-cost substitute founded on Long Range (LoRa) to realize similar localization capabilities, based on the Received Signal Strength Indicator (RSSI) techniques. LoRa transceivers support swift deployment in GPS-less emergency scenarios, providing emergency teams with critical location and sensing data. According to outdoor experimental results, LoRa is a promising solution for wireless localization systems at GPS-less environments.

For RC columns exposed to blast loads, fibre reinforced polymer (FRP) is employed to examine its effectiveness in strengthening the concrete structure against blast load. It should be noted that no systematic studies could be found in the literature to derive pressure and impulse (P-I) diagram for FRP retrofitted RC columns. Therefore, the objective of this research is to develop finite element model to provide data for use in the development of P-I diagram that can be used to mitigate blast hazards and predict damage in RC columns retrofitted with FRP. In this study, various strengthening scheme performed against blast loads numerically by running computer simulations using the commercial software LS-DYNA. Validation of the models is performed based on the blast field test to investigate the accuracy of model simulations to present the behaviour of the models. The research compared the structural behaviour of an un-strengthened RC column with various column strengthened with different FRP wrap thickness, strength and arrangement. The results of the simulations showed that strengthening with FRP is an effective way to increase the blast resistance capacity of columns. This information would allow the designer to identify the critical location for placing blast barriers for protection purpose.

In trolleybuses in service, fatigue cracks were frequently encountered in a welded structural detail in their rear axle housing. Sufficiently representative stress-time histories for the critical cross section through this part were obtained by measurement during rides with empty as well as fully-loaded vehicles. The fatigue characteristics of the critical location had to be established by estimation. This information was used as the basis for parametric calculations of fatigue life. The main purpose of these calculations was to ascertain whether these in-service failures could have been predicted (and prevented) during the design stage, and what their main cause had been. Furthermore, this investigation explored the feasibility of verifying this structural detail's service life using the fatigue life distribution function.

Voltage stability margins of modernbulk power systems are significantly affected by renewable energy sources (RESs). The intermittency of these units can constantly move the critical location driving the system to voltage collapse along different coherence regions. Traditional approaches were not designed to deal with this scenario, typically providing a centralized actuation based on a system-wide perspective. In this sense, this paper proposes a novel area-based outlook to take advantage of the new possibilities enabled by power systems distributed controllable resources, e.g. flexible resources, to tackle this critical operational challenge. For this sake, a novel area-based sensitivity index, exploring both the network-wide sensitivity and the local characteristics of voltage collapse is proposed to determine the most effective buses for voltage support and their respective capability of increasing the system's load margin. Comparative case studies indicate the superior capability of the proposed direct method to deal with the new perspectives of modern power systems.

This paper explores the drivers of political instability and how political instability affects the economy in the context of Yemen. It is a low country income, although the critical location is at the southern end of the Arabian Peninsula with 200 islands. The country is rife with terrorists and lives under much socio-political strife. We implemented an empirical model to test the correlations and multiple regression between political instability and economic growth. The study found that there is a high negative correlation between volatility and economic growth with negative correlations value. Furthermore, we investigate the significance of the regression -enter method- stepwise method which show the existence of the impact of the political instability index conflict, and civil war in economic growth.

The wing leading edge is one of the aircraft structures which are vulnerable to birdstrike. Therefore, Federal Aviation Regulation has clear requirements of anti-birdstrike performance for wing leading edge. However, the impact location is not specified in aviation regulation. The forefront of the wing leading edge is selected as a critical location for the birdstrike in most researches. But the rationality of the selection is not given. This paper proposes an analytical method for determining the critical location that causes the most severe damage under impact due to birdstrike. The analysis is based on the concept of effective impact, i.e. the component of the bird velocity perpendicular to the surface of wing leading edge. A birdstrike model is established using Pam-crash and used to validate the analytical prediction. The numerical model proves its effectiveness compared to the birdstrike test. The residual compressive strength of the spar when the birdstrike is at the critical impact location determined by the proposed method is 44.5% of that at the traditional impact location. Moreover, the critical penetrating velocity of the traditional impact location is not the lowest. In other words, the traditional impact location is not the weakest. Airworthiness verification experiment of birdstrike on wing structure should pay attention to this aspect.

Pineal region tumors represent a heterogeneous group of different histologic entities, for which the management can be a significant challenge, due to their critical location and frequent aggressive behavior. Traditional management includes surgical resection, fractionated radiation therapy, and chemotherapy. Stereotactic radiosurgery (SRS) is being increasingly used in the treatment of these tumors. It is used as primary therapy for pineocytomas and papillary tumors of the pineal region, as an adjuvant radiation boost in combination with radiation or chemotherapy for pineoblastomas and germ cell tumors, or in the context of tumor recurrence. The reported morbidity is low, consisting in transient oculomotor disturbance in most cases. As a non-invasive alternative to microsurgical resection, SRS should always be considered when discussing these challenging cases.

In the past few decades, effect of natural hazards such as earthquake, wind etc. on existing structures has attracted the attention of designers. Progressive collapse is nothing but a condition of indigenous failure of prime structural element which in turn leads to the collapse of connecting members and then it leads to the additional collapse. For the case of progressive collapse, damage is included in the model through the elimination of important structural component like column. The progressive collapse design guidelines primarily suggest the simplified analysis actions occurred due to the sudden removal of specific columns in a building. The study of analytical approaches for evaluating progressive collapse is carried out by linear static analysis using Alternate Path Method (APM) recommended in General Service Administration (GSA) guidelines and the same is presented in this study. This study involves the use of various general methods of progressive collapse design & evaluation based on numerical mock up and experimental information. For this study, a multistoried composite building (i.e. G+7) is considered. The prime objective of this study is to analyze the composite building by removing columns at different locations and finding out critical location of column vulnerable to progressive collapse and also prevention of progressive collapse of structure using linear static analysis. Location of removed column, Number of floors, vertical irregularity were studied and their influence was also carried out in this research.