bluuebunny/crossref_metadata_2025 huggingface dataset:
Protective effect of blackthorn fruits (Prunus spinosa) against tartrazine toxicity development in albino Wistar rats
Authors: Balta Igori , Sevastre Bogdan , Mireșan Vioara , Taulescu Marian , Raducu Camelia , Longodor Adina Lia , Marchis Zamfir , Maris Stefania , Coroian Aurelia
Published: August 2019

Background: Tartrazine (Yellow 5 or E102) is a synthetic food dye able to modify perception and behavior, causingagitation, confusion, rhinitis and can produce hyperactivity syndrome in children when is combined with benzoates.Additionally, it can trigger oxidative stress which consequently generates metabolic disorders. Therefore, the studywas designed to evaluate the harmful effects of the food additive tartrazine and to observe beneficial properties ofblackthorn fruits (Prunus spinosa) on the blood and organs of albino Wistar rats.Materials and methods: This study was carried out on 20 mature Wistar rats, randomly divided into four groupsof five animals. Over the course of the experiment, the control group received only food and drinking water, group Ireceived 75 mg of tartrazine dissolved in (250 ml) water group II was given 75 mg of tartrazine and 200 mg of driedblackthorn fruit powder 200 mg dissolved simultaneously in (250 ml) of tartrazine-water mixture (aiming to reducethe tartrazine toxicity) and group III received a higher dose of tartrazine (100 mg) in (250 ml) of water.Results: At the end of the experiment, values regarding kidney and liver weight were significantly increased, whilethe weight of the spleen was slightly decreased compared with the weight of the control group. Biochemical andhematological assays, of the blood samples show that the addition of tartrazine in the diet of rats caused significantchanges in all biochemical and hematological parameters of the blood. In the group II, which received (P. spinosa)powder combined with tartrazine, the biochemical and hematological parameters had average values similar to thecontrol group.Conclusions: Histopathological assay showed that the application of tartrazine in the group I, II and III producedlesions of the kidneys, spleen and the liver for all rodents. Tartrazine was able to generate histopathological changes,which caused significantly tissue lesions of the liver and significant changes in blood parameters. Blackthorn powdershowed a promising protective role for the blood parameters but demonstrated no significant benefits for the organs.
Kartelisasi Sitasi Ditinjau Dari Perspektif Kristen
Authors: Darmawan I Putu Ayub , Ronda Daniel
Published: August 2019

Artikel ini membahas isu “kartelisasi sitasi” yang ditinjau dari sudut pandang Kristen. Tinjauan dari sudut pandang Kristen diperlukan agar dapat memberi pandangan bagi akademisi Kristen, sehingga dapat mengambil sikap terkait isu tersebut. Dari hasil analisis, “kartelisasi sitasi” merupakan tindakan pengendalian sitasi dalam upaya meningkatkan jumlah sitasi yang akhirnya berdampak pada meningkatnya peringkat indeks di mesin pengindeks maupun peringkat di laman Sinta. Selain itu, “kartelisasi sitasi” merupakan sebuah ketidakjujuran ilmiah, sebab untuk meningkatkan jumlah sitasi dilakukan upaya dengan mendorong orang lain melakukan sitasi pada karya ilmiah seseorang walau tidak terdapat relevansinya.
Intensi berinvestasi di Galeri
Authors: Dr. Hasrini Sari ST
Published: August 2019

Galeri investasi merupakan kerjasama 3 pihak, yaitu BEI, sekuritas, serta universitas yang bertujuan meningkatkan jumlah investor, khususnya dari kalangan civitas academica. Namun, dalam satu tahun terakhir, lebih dari 50% galeri investasi gagal memenuhi target pertumbuhan jumlah investor. Oleh karena itu, perlu dilakukan perancangan terhadap galeri investasi yang lebih berorientasi pada keinginan dan kebutuhan investor dan investor potensial. Penelitian ini menggali faktor-faktor yang dipertimbangkan investor pada saat akan bertransaksi efek melalui galeri investasi dan berinvestasi kembali. Faktor-faktor diturunkan dari studi literatur dan wawancara terhadap pelanggan galeri dan manajemen BEI sehingga diperoleh 12 faktor. Faktor-faktor tersebut diturunkan menjadi 32 indikator dan diuji dengan menggunakan kuesioner daring dan luring terhadap 193 responden dari 7 galeri investasi terbaik di Indonesia. Data yang diperoleh diolah dengan menggunakan analisis faktor sehingga membentuk 5 faktor yaitu perceived image, customer experience, benefit, facilities, serta response time. Hasil ini kemudian diolah untuk melihat hubungan tiap faktor terhadap intensi untuk berinvestasi kembali. Berdasarkan analisis regresi linier majemuk, hanya 4 faktor yang berpengaruh secara signifikan, yaitu perceived image, benefit, facilities, serta customer experience. Hasil penelitian kemudian digunakan untuk menyusun strategi pemasaran galeri investasi.
DevSim: A PowerPoint-Based Simulator Game for Teaching Economic Development
Authors: Fabian Mark
Published: August 2019

This paper explains how to use a game (“DevSim”) built using PowerPoint with an embedded Excel spreadsheet. You can find the game file at the "supplementary materials" link. DevSim plays out key structural changes studied in development economics. The game is inspired by Sid Meier’s simulators, namely Civilization and Alpha Centauri. It provides a fun way to introduce students to central themes of economic development including industrialization, demographic transition, sources of growth, trade, institutions, diminishing returns when land is a fixed factor, the resource curse, and the importance of productivity. The foundation of the game is a production function, with the class allocating labor and capital to different industries each turn in order to grow their economy. More advanced concepts like trade and institutions are introduced each turn in the form of exogenous shocks.
Activities of Student Centralisation, Questionnaire, Modelling, and KBAT Among Science and Non-Science Students
Authors: Shuib Tajul Rosli , Husin Mohd Razimi , Che Md Ghazali Nor Hasnida
Published: August 2019

The purpose of this study was to identify whether or not there was a significant difference in the variables of student centralisation, teacher questioning, teacher modelling and high-level thinking skills of students based on class stream for low-performing school students in Kudat, Sabah, Malaysia. This quantitative study used a survey method involving 250 respondents from the stated population. This study referred to the Absorption Learning Model (Swartz, Fischer and Parks, 1998) as the basis model for the study. The data were analysed using the T-test with Statistical Packages for Social Science (SPSS) version 22. Based on the class stream in Kudat district, the findings showed that there was a significant difference in the involvement of student centralisation between Science and non-Science students; there was no significant difference in teachers' questioning between Science and non-Science students; there was no significant difference in teacher modelling between Science and non-Science students; there was a significant difference in thinking skills level between Science and non-Science students. It is hoped that this study can provide useful inputs for improving the practice of teaching infusion of teachers to students from every class stream in Kudat region in particular and throughout Malaysia in general.
Controllable Fabrication and Characterization of Gold Nanoparticles: Enhanced Therapeutic Approaches in Cancer
Authors: Ikram Aqsa , Jamil Yasir , Ahmad Tahira , Ikram Hira , Ameen Amna , Qayyum Soban
Published: August 2019

Energy trans-ducting gold nano-particles, with well-being physical, chemical and optical properties for utilization in different types of cancer therapy can be prepared through chemical seed growth reduction method. Gold nano particle is a umbrella term have a variety of size and shape. More regular gold nano-particles can be obtained by reduction of HAuCl4, selection of chemicals and parameters of growth medium are set in accordance with the required category of nano-particles. Nano-particles have longest dimension of 100 nm. Therapeutic treatments like photo-imaging, gene delivery, drug delivery, cell labeling and photo thermal therapy   can be done by gold nano particles.  They reduce the side effects of conventional therapy due to high target specificity and absorb and scatter specific wavelength of laser. Hyperthermia in cancerous cells is generated without damaging surrounding healthy tissues, cause the cell death by necrosis and apoptosis. The overall morphology of gold nano particles can be characterized by SEM and TEM.
Concentration of rare-earth elements by sorption from sulphate solutions
Authors:   Satbayev University, B.K. Kenzhaliyev  ,   “Institute of Metallurgy and Ore Beneficiation” JSC, Т.Yu. Surkova  ,   Satbayev University; “Institute of Metallurgy and Ore Beneficiation” JSC, D.M. Yessimova  ,   Satbayev University; “Institute of Metallurgy and Ore Beneficiation” JSC
Published: August 2019

Constantly increasing demand for rare-earth elements contributes to the involvement in the production of ore processing waste, the content of not extracted REE in which is quite large. One of the types of such waste is man-made mineral formations from the processing of phosphate uranium ores, which serve as raw materials for the production of REE concentrate at SARECO LLP. The technology for producing a concentrate includes the following redistribution: opening of raw materials cleaning of productive solutions from impurities; obtaining a concentrate on rare earth elements. One of the main disadvantages of this technology is the coprecipitation of almost 30% REE with ferrous cake when cleaning the most productive solution from impurities. To extract the rare earth elements ferrous cake is leached with sulphuric acid. The article studies the process of sorption from both model solutions that are similar in composition to the productive leaching of ferrous cake and directly from the productive ones, with the aim of further combining the resulting eluates with solutions supplied to precipitate REE.. Considerable attention has been paid to disrupt by ammonium salts.
Physical and chemical researches of nickel-cobalt concentrates made from wastes of heat-resistant nickel alloys
Authors:   “Institute of Metallurgy and Ore Beneficiation” JSC, Kilibayeva S.K. ,   Satbayev University, Almaty, Kazakhstan, Agapova L.Y. ,   “Institute of Metallurgy and Ore Beneficiation” JSC; Satbayev University, Almaty, Kazakhstan, Kvyatkovskaya M.N. ,   “Institute of Metallurgy and Ore Beneficiation” JSC; Satbayev University, Almaty, Kazakhstan, Amanzholova L.U. ,   “Institute of Metallurgy and Ore Beneficiation” JSC; Satbayev University, Almaty, Kazakhstan, Kuchsh H.P. ,   “Institute of Metallurgy and Ore Beneficiation” JSC; Satbayev University, Almaty, Kazakhstan
Published: August 2019

The wastes of rhenium-containing heat-resistant nickel alloys (HRNA) contain 50-75% of Ni, 3-15% of Co. While electrochemical processing of the wastes of the HRNA up to 80-90% of Re, Ni and Co passes into the solutions, and a small part of them remains in the anode slurry. The remaining part of the metals from the slurry is chemically dissolved into the solution. After electrochemical treatment of wastes and chemical dissolution of slurry the solutions are combined and Re is extracted from them. The Ni – Co concentrate was precipitated (until a pH of 8–9 was established, at a temperature of 40 °C, by intensive stirring for 1 h) from the raffinate (g/dm3: 14.26 Ni; 2.48 Co) after the extraction of Re by NaOH (500 g/dm3) solution. Physical and chemical studies of the concentrate using X-ray fluorescent, X-ray phase, thermo gravimetric and X-ray methods showed that it contains the following phases, wt. %: 62.6 Na2SO4; 37.4 Ni2 (NO3)2 (OH)2 • 2H2O and Co (OH)2. Washing the concentrate from sodium by water at L:S = 10: 1 ratio allowed reducing its mass (~ 2.4 times), reducing the content of sodium, increasing the content of Ni (from 15.68 to 37.55 %) and Co (from 1.89 to 4.48%). When the concentrate is annealed in the temperature range of 300-400 °C, the processes of dehydration of the hydroxides of Ni and Co and their transition to the oxide forms occur. The resulting concentrate can be sent for further processing in order to extract non-ferrous metals from it or used to produce some ferroalloys.
Plant-Derived Essential Oils; Their Larvicidal Properties and Potential Application for Control of Mosquito-Borne Diseases
Authors: Osanloo Mahmoud , Sedaghat Mohammad Mehdi , Sanei-Dehkordi Alireza , Amani Amir
Published: August 2019

Mosquito-borne diseases are currently considered as important threats to human health in subtropical and tropical regions. Resistance to synthetic larvicides in different species of mosquitoes, as well as environmental pollution, are the most common adverse effects of excessive use of such agents. Plant-derived essential oils (EOs) with various chemical entities have a lower chance of developing resistance. So far, no proper classification based on lethal concentration at 50% (LC50) has been made for the larvicidal activity of EOs against different species of Aedes, Anopheles and Culex mosquitoes. To better understand the problem, a summary of the most common mosquito-borne diseases have been made. Related articles were gathered, and required information such as scientific name, used part(s) of plant, target species and LC50 values were extracted. 411 LC50 values were found about the larvicidal activity of EOs against different species of mosquitoes. Depending on the obtained results in each species, LC50 values were summarized as follows: 24 EOs with LC50 < 10 µg/mL, 149 EOs with LC50 in range of 10- 50 µg/mL, 143 EOs having LC50 within 50- 100 µg/mL and 95 EOs showing LC50 > 100 µg/mL. EOs of Callitris glaucophylla and Piper betle against Ae. aegypti, Tagetes minuta against An. gambiae, and Cananga odorata against Cx. quinquefasciatus and An. dirus having LC50 of ~ 1 µg/mL were potentially comparable to synthetic larvicides. It appears that these plants could be considered as candidates for botanical larvicides. [GMJ.2019;8:e1532]
Evaluation of Lung Density and Its Dosimetric Impact on Lung Cancer Radiotherapy: A Simulation Study
Authors: Raj Verma T , Kumar Painuly N , Prasad Mishra S , Yoganathan S A , Singh N , Bhatt M L B , Jamal N
Published: August 2019

Background: The dosimetric parameters required in lung cancer radiation therapy are taken from a homogeneous water phantom; however, during treatment, the expected results are being affected because of its inhomogeneity. Therefore, it becomes necessary to quantify these deviations.Objective: The present study has been undertaken to find out inter- and intra- lung density variations and its dosimetric impact on lung cancer radiotherapy using Monte Carlo code FLUKA and PBC algorithms.Material and Methods: Density of 100 lungs was recorded from their CT images along with age. Then, after PDD calculated by FLUKA MC Code and PBC algorithm for virtual phantom having density 0.2 gm/cm3 and 0.4 gm/cm3 (density range obtained from CT images of 100 lungs) using Co-60 10 x10 cm2 beams were compared.Results: Average left and right lung densities were 0.275±0.387 and 0.270±0.383 respectively. The deviation in PBC calculated PDD were (+)216%, (+91%), (+)45%, (+)26.88%, (+)14%, (-)1%, (+)2%, (-)0.4%, (-)1%, (+)1%, (+)4%, (+)4.5% for 0.4 gm/cm3 and (+)311%, (+)177%, (+)118%, (+)90.95%, (+)72.23%, (+)55.83% ,(+)38.85%, (+)28.80%, (+)21.79%, (+)15.95%, (+)1.67%, (-) 2.13%, (+)1.27%, (+)0.35%, (-)1.79%, (-)2.75% for 0.2 gm/cm3 density mediums at depths of 1mm, 2mm, 3mm, 4mm, 5mm, 6 mm, 7 mm, 8mm, 9mm,10mm, 15mm, 30mm, 40mm, 50mm, 80mm and 100 mm, respectively.Conclusion: Large variations in inter- and intra- lung density were recorded. PBC overestimated the dose at air/lung interface as well as inside lung. The results of Monte Carlo simulation can be used to assess the performance of other treatment planning systems used in lung cancer radiotherapy.
Detection and Characterization of Human Teeth Caries Using 2D Correlation Raman Spectroscopy
Authors: El-Sharkawy Y H
Published: August 2019

Background: Carious lesions are formed by a complex process of chemical interaction between dental enamel and its environment. They can cause cavities and pain, and are expensive to fix. It is hard to characterize in vivo as a result of environment factors and remineralization by ions in the oral cavity. Objectives: The development of a technique that gives early diagnosis which is non-invasive, is of crucial importance for publichealth. Raman spectroscopy is a technique that can fulfil these requirements. The main goal of this work was to use Raman spectroscopy to differentiate between normal and carious human teethinvivo. The samples used in this study were collected by traditional human teeth. Method: An in vivo Raman spectroscopy system andspecialized fiber optic probe has been designed to obtain spectra from tissue. Theseprobes are filtered to reduce the background signal from the fiber optics and the collection fiberutilizes beam steering to optimize the collection effectiv. Results: In order to detect any demineralization and carious versus sound pit and fissure enamel, the spectral data sets are analyzed by the proposed scheme to demonstrate the utility of generalized 2D correlation spectra. Potential applications of this 2D correlation approach are then explored. The Raman spectra in the normal tissue showed thepresence of vibrational bands in 437.87 cm-1, 581.89 cm-1, 953.89 cm-1 and 1054.73 cm-1 with smaller intensity than in the carious spectra. Image construction from the peak intensity produced chemical maps of apatite concentration.Conclusion: Such two-dimensional correlation spectra emphasize spectral features not readily observable in conventional one-dimensional spectra.No correlation is observed in mode-to-mode intensity fluctuations indicating that the changes inmode intensities are completely independent. Theoreticalcalculations provide convincing evidence that the fluctuationsare not the result of diffusion, orientation or local electromagnetic field gradients but rather are the result of subtle variations ofthe excited-state lifetime, energy and geometry of the molecule and producing a signature response for carious detection.
Evaluation of Electron Specific Absorbed Fractions in Organs of Digimouse Voxel Phantom Using Monte Carlo Simulation Code FLUKA
Authors: Sinha A , Singh N , Dixit B M , Painuly N K , Patni H K , Yadav A
Published: August 2019

Background: For preclinical evaluations of radiopharmaceuticals, most studies are carried out on mice. Values of electron specific absorbed fractions (SAF) have had vital role in the assessment of absorbed dose. In past studies, electron specific absorbed fractions were given for limited source target pairs using older reports of human organ compositions.Objective: Electron specific absorbed fraction values for monoenergetic electrons of energies 15, 50, 100, 500, 1000 and 4000 keV were evaluated for the Digimouse voxel phantom incorporated in Monte Carlo code FLUKA. The organ sources considered in this study were lungs, skeleton, heart, bladder, testis, stomach, spleen, pancreas, liver, kidney, adrenal, eye and brain. The considered target organs were lungs, skeleton, heart, bladder, testis, stomach, spleen, pancreas, liver, kidney, adrenal and brain. Eye and brain were considered as target organs only for eye and brain as source organs. From the latest report (International Commission on Radiological Protection ICRP) publication number 110, organ compositions and densities were adopted.Results: The electron specific absorbed fraction values for self-irradiation decreases with increasing electron energy. The electron specific absorbed fraction values for cross-irradiation are also found to be dependent on the electron energy and the geometries of source and target. Organ masses and electron specific absorbed fraction values are presented in tabular form. Conclusion: The results of this study will be useful in evaluating the absorbed dose to various organs of mice similar in size to the present study.
A Novel Virtual Reality Technique (Cervigame®) Compared to Conventional Proprioceptive Training to Treat Neck Pain: A Randomized Controlled Trial
Authors: Rezaei I , Razeghi M , Ebrahimi S , Kayedi S , Rezaeian Zadeh A
Published: August 2019

Background: Despite the potential benefits of virtual reality technology in physical rehabilitation, only a few studies have evaluated the efficacy of this type of treatment in patients with neck pain.Objective: The aim of this study was to compare the effects of virtual reality training (VRT) versus conventional proprioceptive training (CPT) in patients with neck pain.Methods: Forty four participants with nonspecific chronic neck pain were randomly assigned to VRT or CPT in this assessor-blinded clinical trial. A novel videogame called Cervigame® was designed for VRT. It comprises of 50 stages divided into unidirectional and two-directional stages ordered from easy to hard. CPT consisted of eye-follow, gaze stability, eye-head coordination and position and movement sense training. Both groups completed 8 training sessions over 4 weeks. Visual analogue scale score, neck disability index and Y-balance test results were recorded at baseline, immediately after and 5 weeks post-intervention. Mixed repeated measure ANOVA was used to analyze differences between mean values for each variable at an alpha level of 0.05.Results: There were significant improvements in all variables in both groups immediately after and 5 weeks after the intervention. Greater improvements were observed in the visual analogue scale and neck disability index scores in VRT group, and the results for all directions in Y-balance test were similar in both groups. No side effects were reported.Conclusion: Improvements in neck pain and disability were greater in VRT than CPT group. Cervigame® is a potentially practical tool for rehabilitation in patients with neck pain.
Calculating Weighting Factors for Mixing Megavoltage Photon Beams to Achieve Desirable Dose Distribution in Radiotherapy
Authors: Tahmasebi Birgani M J , Chegeni N , Tahmasbi M , Hazbavi M , Hoseini S M
Published: August 2019

Background: In radiotherapy, low-energy photon beams are better adapted to the treated volume, and the use of high-energy beams can reduce hot spots in the radiation therapy. Therefore, mixing low and high energies with different ratios can control the rate of hotspots, as well as the dose distribution of the target volume.Material and Methods: The percentage depth doses (PDDs) were calculated at various depths, by using a fitted double exponential equation. Then, using quality factor equation and PDD of a 10×10 cm2 field, the amount of energy equivalent to each PDD and the value of weighting factors of 6, 18 MV energies were calculated to produce different energies. To validate the mathematical model, dosimetry of 10 MV energy was used. For this purpose, PDDs and dose Profile of 10 MV obtained from the mix were compared with ones obtained from the measurementResults: The value of weighting factor of 6 MV energy required for the 10 ×10 cm2 field to create dose distribution of 15 MV energy using 6 and 18 MV energies was obtained as equal to 0.57. Comparison of percentage depth dose curves and dose profile shows good agreement with the practical measurements of 10 MV for 10×10 cm2 field using gamma index.Conclusion:The simultaneous use of high and low photon energies with different weighting factors to achieve desirable energy makes possible the treatment of tumors located at various depths without the need for different modes of energy in the accelerator leading to a decrease in the cost of the equipment and a safer treatment of the cancerous patients.
Roll-over analysis of a new design carbon fiber prosthetic foot
Authors: Noori Hamzah Mohsin , AbdulhessenGatta Abdurrahman
Published: August 2019

Many researchers adopted the quasi static roll over testing in the calculation of a prototype prosthetic feet roll over shape. In this work, the prototype of a new carbon fiber prosthetic foot was tested for roll over characteristic. An inverted pendulum like apparatus has been built to achieve the required test, and the prosthesis roll over shape calculated. Roll over characteristics were estimated as: effective radius of curvature about 202mm, center of curvature of 26.55mm, and the forward travel against shank angle was plotted.
Multi-Objective Optimization of Turning Process during Machining of AISI 1025 on CNC machine Using Multi-objective particle swarm optimization
Authors: E. Radhi H. , jammel alsalhy Mohammed
Published: August 2019

Parametric optimization of the transformation process is a task of improving multiple objectives. In general, no single set of input parameters can provide the best hardness of the metal and the best finish of the surface at the same time. While when using the genetic algorithm proved that it is possible to obtain more than one goal of the function at the same time. In the current research the use of Multi-objective particle swarm optimization (MOPSO) to determine the best hardness of the metal and less roughness of the surface operator at the same time. A mathematical model was also developed to predict the hardness of the metal and surface roughness using Taguchi technology depending on the input variables (cutting speed, cutting depth and feeding rate). Experiments were conducted on a CNC machine in turning carbon steel AISI 1025 using carbide cutting tool. It was found that the most influential factor on the surface roughness is the feeding  rate, while the most important effect on the hardness is the cutting speed.
The benefit and risk of stereotactic radiosurgery for prolactinomas: an international multicenter cohort study
Authors: Hung Yi-Chieh , Lee Cheng-Chia , Yang Huai-che , Mohammed Nasser , Kearns Kathryn N. , Nabeel Ahmed M. , Abdel Karim Khaled , Emad Eldin Reem M. , El-Shehaby Amr M. N. , Reda Wael A. , Tawadros Sameh R. , Liscak Roman , Jezkova Jana , Lunsford L. Dade , Kano Hideyuki , Sisterson Nathaniel D. , Martínez Álvarez Roberto , Martínez Moreno Nuria E. , Kondziolka Douglas , Golfinos John G. , Grills Inga , Thompson Andrew , Borghei-Razavi Hamid , Maiti Tanmoy Kumar , Barnett Gene H. , McInerney James , Zacharia Brad E. , Xu Zhiyuan , Sheehan Jason P.
Published: August 2019

OBJECTIVE

The most common functioning pituitary adenoma is prolactinoma. Patients with medically refractory or residual/recurrent tumors that are not amenable to resection can be treated with stereotactic radiosurgery (SRS). The aim of this multicenter study was to evaluate the role of SRS for treating prolactinomas.

METHODS

This retrospective study included prolactinomas treated with SRS between 1997 and 2016 at ten institutions. Patients’ clinical and treatment parameters were investigated. Patients were considered to be in endocrine remission when they had a normal level of prolactin (PRL) without requiring dopamine agonist medications. Endocrine control was defined as endocrine remission or a controlled PRL level ≤ 30 ng/ml with dopamine agonist therapy. Other outcomes were evaluated including new-onset hormone deficiency, tumor recurrence, and new neurological complications.

RESULTS

The study cohort comprised 289 patients. The endocrine remission rates were 28%, 41%, and 54% at 3, 5, and 8 years after SRS, respectively. Following SRS, 25% of patients (72/289) had new hormone deficiency. Sixty-three percent of the patients (127/201) with available data attained endocrine control. Three percent of patients (9/269) had a new visual complication after SRS. Five percent of the patients (13/285) were recorded as having tumor progression. A pretreatment PRL level ≤ 270 ng/ml was a predictor of endocrine remission (p = 0.005, adjusted HR 0.487). An increasing margin dose resulted in better endocrine control after SRS (p = 0.033, adjusted OR 1.087).

CONCLUSIONS

In patients with medically refractory prolactinomas or a residual/recurrent prolactinoma, SRS affords remarkable therapeutic effects in endocrine remission, endocrine control, and tumor control. New-onset hypopituitarism is the most common adverse event.
Conflicts of interest in randomized controlled trials reported in neurosurgical journals
Authors: Staartjes Victor E. , Klukowska Anita M. , Sorba Elena L. , Schröder Marc L.
Published: August 2019

OBJECTIVE

Randomized controlled trials (RCTs) form the basis of today’s evidence-based approach to medicine, and play a critical role in guidelines and the drug and device approval process. Conflicts of interest (COIs) are commonplace in medical research, but little is known about their influence. The authors aimed to evaluate the extent and influence of COIs in recent RCTs published in core neurosurgical journals using a cross-sectional analysis.

METHODS

Through review of 6 general neurosurgical journals, all interventional RCTs published from January 2009 to January 2019 were identified. Because it is difficult to objectively assess study outcome, the authors opted for a strict rating approach based on the statistical significance of unambiguously reported primary endpoints, and the reported statistical protocol.

RESULTS

A total of 129 RCTs met the inclusion criteria. During the study period, the Journal of Neurosurgery published the largest number of RCTs (n = 40, 31%). Any potential COI was disclosed by 57%, and a mean of 12% of authors had a personal COI. Nonfinancial industry involvement was reported in 10%, while 31% and 20% received external support and sponsoring, respectively. Study registration was reported by 56%, while 51% of studies were blinded. Registration showed an increasing trend from 17% to 76% (p < 0.001). The median randomized sample size was 92 (interquartile range 50–153), and 8% were designed to investigate noninferiority or equality. Sixty-three RCTs (49%) unambiguously reported a primary endpoint, of which 13% were composite primary endpoints. In 43%, study outcome was positive, which was associated with a noninferiority design (31% vs 3%, p = 0.007) and a composite primary endpoint (46% vs 9%, p = 0.002). Potential COIs were not significantly associated with study positivity (69% vs 59%, p = 0.433). In the multivariate analysis, only a composite primary endpoint remained predictive of a positive study outcome (odds ratio 6.34, 95% confidence interval 1.51–33.61, p = 0.017).

CONCLUSIONS

This analysis provides an overview of COIs and their potential influence on recent trials published in core neurosurgical journals. Reporting of primary endpoints, study registration, and uniform disclosure of COIs are crucial to ensure the quality of future neurosurgical randomized trials. COIs do not appear to significantly influence the outcome of randomized neurosurgical trials.
Form follows function: estimation of CSF flow in the third ventricle–aqueduct–fourth ventricle complex modeled as a diffuser/nozzle pump
Authors: Longatti Pierluigi , Fiorindi Alessandro , Peruzzo Paolo , Basaldella Luca , Susin Francesca Maria
Published: August 2019

OBJECTIVE

In the last 20 years, researchers have debated cerebrospinal fluid (CSF) dynamics theories, commonly based on the classic bulk flow perspective. New hypotheses do not consider a possible hydraulic impact of the ventricular morphology. The present study investigates, by means of a mathematical model, the eventual role played by the geometric shape of the “third ventricle–aqueduct–fourth ventricle” complex in CSF circulation under the assumption that the complex behaves like a diffuser/nozzle (DN) pump.

METHODS

DN pumps are quite recent devices introduced as valveless micropumps in various industrial applications given their property of driving net flow when subjected to rhythmic pulsations. A novel peculiar DN pump configuration was adopted in this study to mimic the ventricular complex, with two reservoirs (the ventricles) and one tube provided with a conical reach (the aqueduct–proximal fourth ventricle). The flow was modeled according to the classic equations of laminar flow, and the external rhythmic pulsations forcing the system were reproduced as a pulsatile pressure gradient between the chambers. Several physiological scenarios were implemented with the integration of data acquired by MRI in 10 patients with no known pathology of CSF dynamics, and a quantitative analysis of the effect of geometric and hydraulic parameters (diverging angle, sizes, frequency of pulsations) on the CSF net flow was performed.

RESULTS

The results showed a craniocaudal net flow in all the given values, consistent with the findings of cine MRI studies. Moreover, the net flow estimated for the analyzed cohort of patients ranged from 0.221 to 0.505 ml/min, remarkably close to the values found on phase contrast cine MRI in healthy subjects. Sensitivity analysis underlines the pivotal role of the DN configuration, as well as of the frequency of forcing pressure, which promotes a relevant net flow considering both the heart and respiration rate.

CONCLUSIONS

This work suggests that the geometry of the third ventricle–aqueduct–fourth ventricle complex, which resembles a diverter, appears to be functional in the generation of a net craniocaudal flow and potentially has an impact on CSF dynamics. These conclusions can be drawn by observing the analogies between the shape of the ventricles and the geometry of DN pumps and by recognizing the basis of the mathematical model of the simplified third ventricle–aqueduct–fourth ventricle complex proposed.
Vasa vasorum formation is associated with rupture of intracranial aneurysms
Authors: Miyata Haruka , Imai Hirohiko , Koseki Hirokazu , Shimizu Kampei , Abekura Yu , Oka Mieko , Kawamata Takakazu , Matsuda Tetsuya , Nozaki Kazuhiko , Narumiya Shuh , Aoki Tomohiro
Published: August 2019

OBJECTIVE

Subarachnoid hemorrhage (SAH) has a poor outcome despite modern advancements in medical care. The development of a novel therapeutic strategy to prevent rupture of intracranial aneurysms (IAs) or a novel diagnostic marker to predict rupture-prone lesions is thus mandatory. Therefore, in the present study, the authors established a rat model in which IAs spontaneously rupture and examined this model to clarify histopathological features associated with rupture of lesions.

METHODS

Female Sprague Dawley rats were subjected to bilateral ovariectomy; the ligation of the left common carotid, the right external carotid, and the right pterygopalatine arteries; induced systemic hypertension; and the administration of a lysyl oxidase inhibitor.

RESULTS

Aneurysmal SAH occurred in one-third of manipulated animals and the locations of ruptured IAs were exclusively at a posterior or anterior communicating artery (PCoA/ACoA). Histopathological examination using ruptured IAs, rupture-prone IAs induced at a PCoA or ACoA, and IAs induced at an anterior cerebral artery–olfactory artery bifurcation that never ruptured revealed the formation of vasa vasorum as an event associated with rupture of IAs.

CONCLUSIONS

The authors propose the contribution of a structural change in an adventitia, i.e., vasa vasorum formation, to the rupture of IAs. Findings from this study provide important insights about the pathogenesis of IAs.
Usefulness of positron emission tomography for differentiating gliomas according to the 2016 World Health Organization classification of tumors of the central nervous system
Authors: Takei Hiroaki , Shinoda Jun , Ikuta Soko , Maruyama Takashi , Muragaki Yoshihiro , Kawasaki Tomohiro , Ikegame Yuka , Okada Makoto , Ito Takeshi , Asano Yoshitaka , Yokoyama Kazutoshi , Nakayama Noriyuki , Yano Hirohito , Iwama Toru
Published: August 2019

OBJECTIVE

Positron emission tomography (PET) is important in the noninvasive diagnostic imaging of gliomas. There are many PET studies on glioma diagnosis based on the 2007 WHO classification; however, there are no studies on glioma diagnosis using the new classification (the 2016 WHO classification). Here, the authors investigated the relationship between uptake of 11C-methionine (MET), 11C-choline (CHO), and 18F-fluorodeoxyglucose (FDG) on PET imaging and isocitrate dehydrogenase (IDH) status (wild-type [IDH-wt] or mutant [IDH-mut]) in astrocytic and oligodendroglial tumors according to the 2016 WHO classification.

METHODS

In total, 105 patients with newly diagnosed cerebral gliomas (6 diffuse astrocytomas [DAs] with IDH-wt, 6 DAs with IDH-mut, 7 anaplastic astrocytomas [AAs] with IDH-wt, 24 AAs with IDH-mut, 26 glioblastomas [GBMs] with IDH-wt, 5 GBMs with IDH-mut, 19 oligodendrogliomas [ODs], and 12 anaplastic oligodendrogliomas [AOs]) were included. All OD and AO patients had both IDH-mut and 1p/19q codeletion. The maximum standardized uptake value (SUV) of the tumor/mean SUV of normal cortex (T/N) ratios for MET, CHO, and FDG were calculated, and the mean T/N ratios of DA, AA, and GBM with IDH-wt and IDH-mut were compared. The diagnostic accuracy for distinguishing gliomas with IDH-wt from those with IDH-mut was assessed using receiver operating characteristic (ROC) curve analysis of the mean T/N ratios for the 3 PET tracers.

RESULTS

There were significant differences in the mean T/N ratios for all 3 PET tracers between the IDH-wt and IDH-mut groups of all histological classifications (p < 0.001). Among the 27 gliomas with mean T/N ratios higher than the cutoff values for all 3 PET tracers, 23 (85.2%) were classified into the IDH-wt group using ROC analysis. In DA, there were no significant differences in the T/N ratios for MET, CHO, and FDG between the IDH-wt and IDH-mut groups. In AA, the mean T/N ratios of all 3 PET tracers in the IDH-wt group were significantly higher than those in the IDH-mut group (p < 0.01). In GBM, the mean T/N ratio in the IDH-wt group was significantly higher than that in the IDH-mut group for both MET (p = 0.034) and CHO (p = 0.01). However, there was no significant difference in the ratio for FDG.

CONCLUSIONS

PET imaging using MET, CHO, and FDG was suggested to be informative for preoperatively differentiating gliomas according to the 2016 WHO classification, particularly for differentiating IDH-wt and IDH-mut tumors.
Improving medical student recruitment to neurosurgery
Authors: Lubelski Daniel , Xiao Roy , Mukherjee Debraj , Ashley William W. , Witham Timothy , Brem Henry , Huang Judy , Wolfe Stacey Quintero
Published: August 2019

OBJECTIVE

Neurosurgery seeks to attract the best and brightest medical students; however, there is often a lack of early exposure to the field, among other possible barriers. The authors sought to identify successful practices that can be implemented to improve medical student recruitment to neurosurgery.

METHODS

United States neurosurgery residency program directors were surveyed to determine the number of medical student rotators and medical students matching into a neurosurgery residency from their programs between 2010 and 2016. Program directors were asked about the ways their respective institutions integrated medical students into departmental clinical and research activities.

RESULTS

Complete responses were received from 30/110 institutions. Fifty-two percent of the institutions had neurosurgery didactic lectures for 1st- and 2nd-year medical students (MS1/2), and 87% had didactics for MS3/4. Seventy-seven percent of departments had a neurosurgery interest group, which was the most common method used to integrate medical students into the department. Other forms of outreach included formal mentorship programs (53%), lecture series (57%), and neurosurgery anatomy labs (40%). Seventy-three percent of programs provided research opportunities to medical students, and 57% indicated that the schools had a formal research requirement. On average, 3 medical students did a rotation in each neurosurgery department and 1 matched into neurosurgery each year. However, there was substantial variability among programs. Over the 2010–2016 period, the responding institutions matched as many as 4% of the graduating class into neurosurgery per year, whereas others matched 0%–1%. Departments that matched a greater (≥ 1% per year) number of medical students into neurosurgery were significantly more likely to have a neurosurgery interest group and formal research requirements. A greater percentage of high-matching programs had neurosurgery mentorship programs, lecture series, and cadaver training opportunities compared to the other institutions.

CONCLUSIONS

In recent decades, the number of applicants to neurosurgery has decreased. A major deterrent may be the delayed exposure of medical students to neurosurgery. Institutions with early preclinical exposure, active neurosurgery interest groups, research opportunities, and strong mentorship recruit and match more students into neurosurgery. Implementing such initiatives on a national level may increase the number of highly qualified medical students pursuing neurosurgery.
Intraoperative acquisition of DTI in cranial neurosurgery: readout-segmented DTI versus standard single-shot DTI
Authors: Elliott Cameron A. , Danyluk Hayden , Aronyk Keith E. , Au Karolyn , Wheatley B. Matt , Gross Donald W. , Sankar Tejas , Beaulieu Christian
Published: August 2019

OBJECTIVE

Diffusion tensor imaging (DTI) tractography is commonly used in neurosurgical practice but is largely limited to the preoperative setting. This is due primarily to image degradation caused by susceptibility artifact when conventional single-shot (SS) echo-planar imaging (EPI) DTI (SS-DTI) is acquired for open cranial, surgical position intraoperative DTI (iDTI). Readout-segmented (RS) EPI DTI (RS-DTI) has been reported to reduce such artifact but has not yet been evaluated in the intraoperative MRI (iMRI) environment. The authors evaluated the performance of RS versus SS EPI for DTI of the human brain in the iMRI setting.

METHODS

Pre- and intraoperative 3-T 3D T1-weighted and 2D multislice RS-iDTI (called RESOLVE [readout segmentation of long variable echo-trains] on the Siemens platform) and SS-iDTI images were acquired in 22 adult patients undergoing intraaxial iMRI resections for suspected low-grade glioma (14; 64%), high-grade glioma (7; 32%), or focal cortical dysplasia. Regional susceptibility artifact, anatomical deviation relative to T1-weighted imaging, and tractographic output for surgically relevant tracts were compared between iDTI sequences as well as the intraoperative tract shifts from preoperative DTI.

RESULTS

RS-iDTI resulted in qualitatively less regional susceptibility artifact (resection cavity, orbitofrontal and anterior temporal cortices) and mean anatomical deviation in regions most prone to susceptibility artifact (RS-iDTI 2.7 ± 0.2 vs SS-iDTI 7.5 ± 0.4 mm) compared to SS-iDTI. Although tract reconstruction success did not significantly differ by DTI method, susceptibility artifact–related tractography failure (of at least 1 surgically relevant tract) occurred for SS-iDTI in 8/22 (36%) patients, and in 5 of these 8 patients RS-iDTI permitted successful reconstruction. Among cases with successful tractography for both sequences, maximal intersequence differences were substantial (mean 9.5 ± 5.7 mm, range −27.1 to 18.7 mm).

CONCLUSIONS

RS EPI enables higher quality and more accurate DTI for surgically relevant tractography of major white matter tracts in intraoperative, open cranium neurosurgical applications at 3 T.
Field tests of photogrammetric evaluation technique of snow-glacial surface albedo
Authors: Zhuravskiy D. M. , Prokhorova U. V. , Ivanov B. V. , Yanjura A. S. , Kuprikov N. M. , Kurapov M. V.
Published: August 2019

The article discusses the results of applying in Antarctica an original technique for estimating albedo from photogrammetric data and exposure parameters by an unmanned aerial vehicle (UAV). The complexities of the photogrammetric observations under extreme conditions are considered. Conclusions are drawn on ways to improve the recording equipment and the direction of improving the technique for calculating albedo values based on photogrammetric materials and metadata.
Using radar polarimetry to monitor changes in backscattering mechanisms in landslide zones for the case study of the Bureya river bank collapse
Authors: Bondur V. G. , Chimitdorzhiev T. N. , Dmitriev A. V. , Dagurov P. N. , Zakharov A. I. , Zakharova L. N.
Published: August 2019

The possibilities of radar polarimetry methods for identification of landslide zones are analyzed here. The fact of transformation of the dominant scattering type by the reflecting surface was used as a key feature of the landslide zone. ALOS-2 PALSAR-2 polarimetric data were processed using the Freeman–Durden and Cloude–Pottier decompositions for the four test sites selected in the area of a landslide caused by the Bureya river bank collapse. The decomposition results are consistent with each other in general, however, some areas show significant differences due to the specifics of the basic model provisions. It is shown that before the landslide event on the landslide area there were three main mechanisms of radar signal scattering: surface, volume, and double scattering. After the collapse, this area is characterized by a single scattering from the surface with large-scale irregularities and without vegetation. So, the landslide area can be confidently recognized. The considerable potential of using the radar polarimetry method for remote diagnostics of the effects of landslide phenomena has been demonstrated.
Water circulation in the north-western Bering sea studied by satellite data
Authors: Andreev A. G.
Published: August 2019

The surface water circulation in the Bering Sea for the period from 2002 to 2017 has been investigated using satellite data. In January, the main stream of surface waters was directed to the south-west along the continental slope, and anticyclonic water circulation was observed on the shelf. In July, the surface water flow was oriented to the northeast along the continental slope, and on the shelf the cyclonic movement of water prevailed. The formation of mesoscale anticyclones in the winter period was caused by the supply of shelf waters with low temperature and salinity. The temporal variability of the currents during the summer is associated with coastal upwelling caused by the winds of the southern points over the western part of the Bering Sea. The presence of upwelling and anticyclonic eddies should be considered as one of the factors leading to the formation of a region with a high concentration of chlorophyll near the coast in the summer season.
Evaluación de la calidad de los servicios hoteleros de segunda categoría del sector céntrico de Guayaquil
Authors: Zambrano Camacho Nuria , Arteaga Cisneros Janina
Published: August 2019

La presente investigación trata de la evaluación de la calidad de los servicios en los establecimientos hoteleros de segunda categoría del sector céntrico de la ciudad de Guayaquil, con el objetivo de determinar si existen falencias en el servicio para mejorar  la gestión de sus elementos tangibles e intangibles que inciden en la satisfacción de sus usuarios.De  igual forma se recopilo información por medio de encuestas, lo que permitió conocer la situación actual de los hoteles de segunda categoría así como la percepción que tienen sus usuarios referentes al cumplimiento de sus expectativas y proponer planes de mejora.