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The diagnosis of MS relies on a combination of imaging, clinical examinations, and biological analyses, including blood and cerebrospinal fluid (CSF) assessments. G-Oligoclonal bands (OCBs) are considered a "gold standard" for MS diagnosis due to their high sensitivity and specificity. Recent advancements have involved the introduced of kappa free light chain (k-FLC) assay into cerebrospinal fluid (CSF) and serum (S), along with the albumin quotient, leading to the development of a novel biomarker known as the "K-index" or "k-FLC index". The use of the K-index has been recommended to decrease costs, increase laboratory efficiency, and to skip potential subjective operator-dependent risk that could happen during the identification of OCBs profiles. This review aims to provide a comprehensive overview and analysis of recent scientific articles, focusing on updated methods for MS diagnosis with an emphasis on the utility of the K-index. Numerous studies indicate that the K-index demonstrates high sensitivity and specificity, often comparable to or surpassing the diagnostic accuracy of OCBs evaluation. The integration of the measure of the K-index with OCBs assessment emerges as a more precise method for MS diagnosis. This combined approach not only enhances diagnostic accuracy, but also offers a more efficient and cost-effective alternative. [ABSTRACT FROM AUTHOR]

Abstract: The Kardashian Index was designed for comedic purposes and meant to highlight researchers with minimal scholar contribution but oversized social media influence. We sought to examine attitudes and understanding of the Kardashian index by conducting a retrospective observational study of tweets retrieved from the Twitter API, Academic Track. From July 30th, 2014 to May 1st, 2021, 5826 unique tweets containing the phrase "Kardashian index” or related search terms were identified. Interest in the Kardashian Index peaked around the time of publication (July 30th, 2014), though the metric received continued discussion. One hundred random tweets were analyzed to see if the conversation points were positive, negative, or neutral. A majority (29%) of the tweets were neutral. Twenty-three percent of the tweets addressed the user’s own K-Index value, while 21% and 17% of the tweets were either critical or joking, respectively. Only a minority of tweets are critical of or appreciate the humor of the Kardashian index. The majority discuss the term matter-of-factly. Although the Kardashian Index was created in a lighthearted manner, a more serious tone emerges, prompting questions about the shifting role of scholarly and public influence.

We conducted a statistical study of polar mesospheric summer echoes (PMSEs) in relation to magnetic local time (MLT), considering the geomagnetic conditions using the K-index (or K). Additionally, we performed a case study to examine the velocity profile, specifically for high velocities (≥ ~100 m/s) varying with high temporal resolution at high K-index values. This study utilized the PMSE data obtained from the mesosphere–stratosphere–troposphere radar located in Esrange, Sweden (63.7°N, 21°E). The change in K-index in terms of MLT was high (K ≥ 4) from 23 to 04 MLT, estimated for the time PMSE was present. During the near-midnight period (0–4 MLT), both PMSE occurrence and signal-to-noise ratio (SNR) displayed an asymmetric structure with upper curves for K ≥ 3 and lower curves for K < 3. Furthermore, the occurrence of high velocities peaked at 3–4 MLT for K ≥ 3. From case studies focusing on the 0–3 MLT period, we observed persistent eastward-biased high velocities (≥ 200 m/s) prevailing for ~18 min. These high velocities were accompanied with the systematic motion of profiles at 85–88 km, including large shear formation. Importantly, the rapid variations observed in velocity could not be attributed to neutral wind effects. The present findings suggest a strong substorm influence on PMSE, especially in the midnight and early dawn sectors. The large zonal drift observed in PMSE were potentially energized by local electromagnetic fields or the global convection field induced by the electron precipitation during substorms.

Multiple sclerosis (MS) is a chronic disease of the central nervous system (CNS) most commonly diagnosed in young adults. In recent decades, new treatments have emerged that have radically changed the prognosis and quality of life of these patients. However, this has also raised new challenges in predicting the course and activity of the disease before the development of new neurological deficits that aggravate the disability and in prescribing the most appropriate disease-modifying therapy for the individual patient in a timely manner. One of the possible solutions that could help answer these questions is the use of laboratory biomarkers in MS. In addition to the oligoclonal bands (OGB) and the immunoglobulin G index, which are already well known and clinically useful laboratory tests, other biomarkers have been discovered that can assess the inflammatory and neurodegenerative processes occurring in the CNS. Kappa free light chains and K-index have been identified as new potential diagnostic biomarkers for MS, with similar sensitivity and specificity to OGB. Some biomarkers have also shown the ability to differentiate a clinically isolated syndrome from MS and to identify the clinical course of MS. The concentration of chitinase-3-like protein in the cerebrospinal fluid is currently the only biomarker that can help distinguish MS from a clinically isolated syndrome. Levels of glial fibrillary acidic protein in cerebrospinal fluid and blood serum can help distinguish primary progressive MS from the relapsing-remitting course of this disease. Serum neurofilament light chain levels are considered the most useful biomarker for monitoring disease activity and treatment efficiency. This article discusses the most promising biomarkers for MS diagnosis, disease activity, and treatment response.

Identifying a subgroup of patients who may have an enhanced treatment effect in a randomized clinical trial has received increasing attention recently. For time-to-event outcomes, it is a challenge to define the effectiveness of a treatment and to choose a cutoff time point for identifying subgroup membership, especially in trials in which the two treatment arms do not differ in overall survival. In this paper, we propose a mixture cure model to identify a subgroup for a new treatment that was compared to a classical treatment (or placebo) in a randomized clinical trial with respect to survival time. Using the concordance probability measurement (K-index), we propose a statistic to test the existence of subgroups with effective treatments in the treatment arm. Subsequently, the subgroup is defined by a limited number of covariates based on the estimated area under the curve (AUC). The performance of this method in different scenarios is assessed through simulation studies. A real data example is also provided for illustration. [ABSTRACT FROM AUTHOR]

To delineate the dynamic stability of a moist atmosphere and to measure stability within a statically stable atmosphere, local Richardson number (Ri) and Brunt‐Väisälä (BV) frequency are used in this study. The BV frequency is an important parameter that is widely used in dynamic meteorology and is calculated by replacing potential temperature with equivalent potential temperature in a moist atmosphere. For this purpose, extreme rainfall events were simulated by the WRF model. These events occurred on 9 September 2012 and 28 July 2010 during the summer monsoon in areas of different altitudes (ranging approximately from 100 to 3,500 m) which resulted in flash floods, loss of lives, and property damages in southern and northern parts of Pakistan. In the present case Ri (local Richardson number based on potential temperature) and Rie (local Richardson number based on equivalent potential temperature) are applied to investigate instability (Rie < 1) in a moist atmosphere. The results show that the values of Rie < 1 are mainly located in the lower‐to‐upper troposphere over the rainfall areas. The analysis shows that Rie is more suitable index for describing the convective instability in a moist saturated atmosphere. The results of Ri and Rie were justified with the European Centre for Medium‐Range Weather Forecasts fifth generation reanalysis (ERA5 hourly) available from Climate Data Store. Moreover, negative values of vertical velocity (hPa/s) clearly show large‐scale dynamical uplifting associated with instability resulting in a severe thunderstorm. Further, strong synoptic forcings also play a key role to develop deep convection over the region. In addition, maximum convective available potential energy (3,000 J/kg) and K‐index (>40) were observed over the areas of high instability that dominate its role in enhancing convection during the events. Key Points: The modified version of the Richardson number was used to delineate convective instability in a moist atmosphereIt is a more meaningful indicator of instability in a moist saturated atmosphereThis study might be helpful in extreme weather forecast decision making [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system. Previous studies have shown that cerebrospinal fluid (CSF) kappa free light chains (K-FLCs) may have a role in MS diagnosis. In this regard, the kappa index (K-Index) has demonstrated higher sensitivity, and slightly lower specificity than oligoclonal bands (OCBs), the gold standard for the detection of intrathecal immunoglobulin synthesis, a feature of MS. Here, we evaluated the performance of the K-Index (K-Index = CSF/serum K-FLC divided by CSF/serum albumin) for the differential diagnosis of MS in a cohort of patients with suspected MS. K-FLCs were quantitatively measured in parallel serum and CSF samples by turbidimetry (Freelite Mx reagent on an Optilite system, The Binding Site Group Ltd). From 160 (63.4%) of a total of 252 patients who had K-FLC in CSF

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system. Previous studies have shown that cerebrospinal fluid (CSF) kappa free light chains (K-FLCs) may have a role in MS diagnosis. In this regard, the kappa index (K-Index) has demonstrated higher sensitivity, and slightly lower specificity than oligoclonal bands (OCBs), the gold standard for the detection of intrathecal immunoglobulin synthesis, a feature of MS. Here, we evaluated the performance of the K-Index (K-Index = CSF/serum K-FLC divided by CSF/serum albumin) for the differential diagnosis of MS in a cohort of patients with suspected MS. K-FLCs were quantitatively measured in parallel serum and CSF samples by turbidimetry (Freelite Mx reagent on an Optilite system, The Binding Site Group Ltd). From 160 (63.4%) of a total of 252 patients who had K-FLC in CSF <0.03 mg/dl, below the sensitivity limit of the technique, only one had a diagnosis of MS. However, the absence of OCB in this same patient suggested no synthesis of intrathecal immunoglobulin. Globally, MS patients presented significantly higher K-Index levels than patients without an MS diagnosis (66.96 vs. 0.025, respectively; p < 0.0001). In agreement, patients with positive OCB testing also exhibited higher K-Index levels than patients negative for OCB (65.02 vs. 0.024, respectively; p < 0.0001). An optimal K-Index cutoff of 3.045 was defined by receiver operating characteristic (ROC) analysis for screening suspected MS, achieving a higher diagnostic sensitivity and slightly lower specificity than OCB (Sens. 0.9778 and Spec. 0.8629 vs. Sens. 0.8889 and Spec. 0.9086, respectively). A previously reported K-Index cutoff of 6.6 also showed good diagnostic performance (Sens. 0.9333; Spec. 0.8731), validating its power as a diagnostic biomarker for MS. Finally, a time- and cost-effective algorithm for MS screening is proposed that would offer an initial rapid evaluation of the intrathecal immunoglobulin synthesis through the K-FLC in CSF and K-Index analysis, followed by reflexing OCB testing that may be ordered more selectively. [ABSTRACT FROM AUTHOR]

The best possible methods are needed to evaluate the scientific excellence of individuals and research groups in order to award positions and distribute research grants with higher efficiency. It is shown here that for the symmetrical distribution of citations of an individual the currently used h-index is approximately half of the square root of the total number of citations, according to the rule of Hirsch. It is also shown that deviations from this “ideal” h-index are common and they are due to deviations in the citation distributions of different individuals. However, those deviations are not characteristic for the scientific excellence of an individual and therefore they lead only to confusion in scientific evaluation. Therefore the h-index is suggested here to be replaced by the k-index. The k-index of an individual is calculated from his/her all independent citations as self-citations cannot be considered as an indication of the excellence of any paper or its authors (the citation is independent if there is no overlap in the lists of authors of the citing and the cited paper). The k-index takes into account only partial citations for each author of multi-authored papers. In ideal case the shares of the authors in a paper are published in the same paper similarly as shares of the inventors are published in patents. If not, the share of each co-author is taken equal to the inverse of the number of authors of the given paper. The k-index of an individual is defined as the square root from the sum of his/her independent partial citations. The value of the k-index is dependent on the databank used for the citations and on the time of the measurement. If scientists of similar age working in similar fields are compared using the same databank, their personal scientific excellence will be proportional to their k-index. When the k-index is divided by the number of active scientific years, a correction can be made for different ages of different applicants. In average, the k-index has similar values, but a wider range compared to the h-index. More importantly the k-index is not biased by this or that type of citation distribution of an individual, not biased by the self-citations and not biased by the results of the co-authors. The squares of k-indexes of smaller units are additive, and so the k-index is extended to journals, publishing houses, departments, institutions, countries, continents and to the mankind.

Представлены результаты сравнительного анализа пространственно-временной изменчивости конвективной неустойчивости на юге Западной Сибири по данным индексов неустойчивости K-Index и Total Totals, полученных из реанализа ERA5. Показано, что по значениям обоих индексов максимум конвективной неустойчивости над югом Западной Сибири приходится на Кулундинскую равнину и пойму верхнего течения р. Иртыш. Кроме того, высокие значения индексов наблюдаются над юго-востоком Урала и северо-востоком Васюганской равнины. Северная граница со значениями KIQ1 ≥ 30 ◦C и TTQ1 ≥ 50 ◦C, указывающими на вероятность образования гроз 70%, простирается до 62◦ и 61◦ с.ш. соответственно. За период 1990–2019 гг. в динамике среднегодовых значений KIQ1, в целом по территории, преобладает положительный тренд, а в динамике TTQ1 на большей части территории значимые изменения отсутствуют, однако отмечается цикличность с периодом ∼ 10 лет.

Today geological active zones unite active faults of lithosphere especially earth’s crust and caused by them zones of increased permeability such as paleo-valleys and underground water flows, karst and geological bodies, that are different in terms of composition and structure from the enclosing rocks. There is an evidence that mortality in geologically active zones increases dramatically, mental instability is detected and road accidents are more frequent. The purpose of this paper is to estimate the frequency of suicides among the residents of Saint Petersburg living above the geologically active zones and outside these zones and the influence of geomagnetic and gravitational disturbances on them. The dynamics of suicides among residents of 446 high-rise building in the territory of the Kalininsky and Vasileostrovsky districts of the city of Saint Petersburg is analyzed. Geological structure of those buildings was most studied. From 1999 to 2003 there were 268 suicides among the residents of such buildings. The group A included homes that were at least 40 m above the nearest tectonic fault. Group B included residential buildings located above or in the immediate vicinity of the faults. During the geomagnetic storms, full moon and new moon periods the number of suicides in a group A decreased. Magnetic storms and gravitational disturbances did not affect the frequency of suicides in a group B. There is also no significant correlation between dynamics of suicides and daily values of the K-index of the geomagnetic field, as well as between dynamics of suicides and the 3-hour geomagnetic activity in both groups. Results of studies presented in this paper show that there is no evidence of a significant negative impact of tectonic faults on people living above them.

Today, the scientists and researchers from almost every corner of the world are well aware of the adverse effects of geomagnetic storms on our highly expensive electrical and electromagnetic systems such as power grid transmission, satellite communication, RF communication systems, etc. The severe damaging effects of these storms on human health and on other inhabitants of the biosphere are also not unknown. A survey of literature on space science reveals that location or space dependency of these geomagnetic storms has already been established. Now the question may arise—Are geomagnetic storms time-dependent? To answer this question, a laborious exercise has been performed. K-index data obtained from the US Department of Commerce, NOAA, Space Weather Prediction Center, for the year, started from 1994 to 2014 (21 years) over three different locations namely Fredericksburg, College, and Estimated Planetary, are analyzed statistically for the eight different time periods namely 00:00–03:00, 03:00–06:00, 06:00–09:00, 09:00–12:00, 12:00–15:00, 15:00–18:00, 18:00–21:00, 21:00–24:00 hours respectively. Results thus obtained have concluded that apart from space or location dependency the geomagnetic storms are time-dependent also. [ABSTRACT FROM AUTHOR]

This research aimed to analyze the impacts of sonication on the rheological properties and color indexes of aqueous solutions of Basil seed gum (BSG), Lallemantia seed gum (LSG), and Wild sage seed gum (WSG). The apparent viscosity (AV) of aqueous solutions of gums decreased with increasing shear rate (SR) from 12.2 s−1 to 134.5 s−1. Also, the AV (at SR = 61 s−1) of BSG, LSG, and WSG solutions reduced from 0.015 to 0.006 Pa.s, 0.023 to 0.010 Pa.s, and 0.009 to 0.004 Pa.s with enhancing the sonication time from 0 to 20 min, respectively. Various rheological equations were employed to fit the empirical values, and the findings confirmed that the Power law (PL) model was the best fit to explain the flow behaviour of these gums solutions. The consistency coefficient (k-index) of BSG, LSG, and WSG solutions significantly (p < 0.05) reduced from 0.108 to 0.017 Pa.sn, 0.143 to 0.033 Pa.sn, and 0.034 to 0.014 Pa.sn with increasing sonication time from 0 to 20 min, respectively. The flow behaviour index (n-index) of the gums solutions increased with increasing sonication time. By applying ultrasound, the lightness (L⁎) and blueness/yellowness (b⁎) indexes of the solutions were increased, and the greenness/redness (a⁎) index was reduced. • Apparent viscosity of seeds gums solutions decreased with increasing shear-rate. • The viscosity and k-index of solutions decreased with increasing sonication time. • Power law model was the best fit to describe flow behaviour of gums solutions. • The n-index of solutions considerably increased with increasing sonication time. • By applying ultrasound, the lightness and yellowness of solutions were increased. [ABSTRACT FROM AUTHOR]

The most common methods used for assessing the relative age of a cave bear bone assemblage are the P4/4 index (morphodynamic index of the cave bear fourth premolar), the K-index and the Index of Plumpness (both used for cave bear’s 2nd metatarsal). Preliminary work on this (Robu et al., 2011), for Urşilor Cave (NW Romania), has indicated one of the youngest European cave bear populations. As the number of extracted fossil bones from the palaeontological excavation increased recently, a re-assessment of the of the age of the cave bear assemblage is necessary. 206 cave bear fourth lower and upper premolars and 587 metapodials were analyzed. The P4/4 morphodynamic index, the K-index and the Index of Plumpness were calculated for the local MIS 3 cave bear bone assemblage. The results of the three indices have lower values when compared with the previously obtained for the same site and respect the subsequent radiometric ages (ca. 47-39 ky BP; Constantin et al., 2014). However, the results for P4/4 morphodynamic index, K-index, and Index of Plumpness are of lesser relevance when used to assess the relative age of MIS 3 cave bear bone assemblages. All three methods require caution when applied and interpreted on short time intervals and on smaller geographic areas.

The myocardial performance index is widely used as an indicator of the heart’s performance. However, due to the subjective nature of ultrasonic testing, there are differences in the measurements among inspectors, requiring a quantitative and objective assessment. In this study, an automated program was developed to quantitatively evaluate the myocardial performance index (MPI) and the cardiac time intervals in the left ventricle for each trimester. One hundred and thirty-three pregnant women who visited the hospital for prenatal examinations were studied, and skilled inspectors obtained left ventricular blood flow waveforms from 47 fetuses in the 12 weeks, 54 fetuses in the 22 weeks, and 32 fetuses in the 31 weeks of pregnancy using a pulse Doppler mode of ultrasound equipment. The acquired images automatically measured the isovolumetric contraction time (IVCT), isovolumetric relaxation time (IVRT,) ejection time (ET), and filling time (FT), and calculated the Tei index (TI) and the K-index (KI); each interval was manually measured during the actual inspection for comparison. In this study, the ultrasonic Doppler waveform was objectively analyzed and measured by the automated program, and it will help with the evaluation of fetal heart function.

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Abstract: We present the results of a statistical analysis of geomagnetic activity measured at the Mikhnevo Geophysical Observatory of the Institute of Geosphere Dynamics of the Russian Academy of Sciences (54.960° N; 37.774° E) located in Moscow region (central part of the Eastern European Platform) and its relation to the solar activity. We use the station geomagnetic K-index as a characteristic of the geomagnetic activity. We apply the results of instrumental observations of the geomagnetic field carried out at the Mikhnevo Geophysical Observatory from 2009 to 2015 to calculate the K-index using the method of adaptive smoothing. The geophysical situation of the Moscow region is characterized by a significant number of days with a disturbed state of the geomagnetic field (in the period analyzed here, magnetic storms were recorded in 181 cases and a disturbed geomagnetic situation was identified in 333 cases). At the same time, there is a tendency for an increase in geomagnetic activity with time: from 2009 to 2015, the number of days with disturbed geomagnetic conditions increased almost eight times. The recurrence of geomagnetic disturbances is characterized by clearly pronounced periodicity with characteristic periods of about 2 weeks, 27 and 60 days, half a year, and 1 year. The total duration of geomagnetic disturbances, which is characterized by K ≥ 4, varies significantly with time. The evaluation of the correlation between the total monthly number of geomagnetic disturbances characterized by a value of K ≥ 3 and the parameter determining the intensity of solar radio emissions (flux density) at a frequency of 2800 MHz (with a wavelength of 10.7 cm) (F 10.7) provide evidence about the significant correlation between the number of geomagnetic disturbances and solar activity. [ABSTRACT FROM AUTHOR]

Background/Objectives: Adolescents experiencing difficulties in real life have many negative experiences in the virtual world, so we should look at the problem of Internet addiction in terms of human computer interaction. Methods/Statistical analysis: This study aimed to investigate the addiction patterns of subjects upon analysis of Internet addiction practices among university students using the K-Index, which is a tool for diagnosing Internet addiction and further analyzing the differences among introvert and extrovert problems according to those patterns. Frequency analyses, descriptive statistics, differences of mean values (t-test and ANOVA), correlation analyses, and reliability tests were used for the analysis. Findings: Adult addiction levels were measured by introvert and extrovert problems using the K-Index. As the sub-variables of Internet addiction, 1.63 out of 4 points was measured for the extrovert level while 1.43 points resulted for the introvert level, which demonstrates higher extrovertly. A t-test was performed to understand the difference of Internet addiction by sex. There was a significant difference according to sex introvertly. In introvert measurements, males had 2.13 points while females had 2.03 points. In extrovert measurements, males scored 2.22 points while females scored 2.19 points. A univariate analysis was performed to understand the difference between age and Internet addiction, and Duncan's Multiple Range Test (MRT) was performed as a post-hoc test. The results indicated that there were no significant differences in dependency, withdrawal symptoms, negative outcomes, and resistance by age. Higher points on the extrovert imply being exposed extrovertly is worse than having introvert conflicts. Males have higher levels extrovertly and introvertly, which indicates males have higher levels of pain. Improvements/Applications: The significant difference between introversion and extroversion is that the problem of Internet addiction should be classified according to the depth of information processing level that humans have. [ABSTRACT FROM AUTHOR]

The solar flare activity is associated with the sunspots activity. The solar flare index data (monthly flare index cycles "20, 21, 22, 23", available on world data center) is used starting from 1966 to 2008 in this research work. The main purpose of this research is to compare the solar flares activity data of north hemisphere, south hemisphere and total hemisphere with K-index activity data using fractal dimension. Persistency (1 < D < 1.5) is observed for each solar cycle of each hemisphere along with the total hemisphere and compare with the associated K-index activity data. Persistency analysis of solar flares activity and K- index activity data will be useful to understand the effects of solar flares dynamics on the K-index dynamics. There is strong bond found between solar flares north hemisphere and K-index data. Hurst exponent is also obtained with the help of fractal dimension (H = 2D) to understand the long rang dependence (self-similarity) of solar flares and K-index activity dynamics. The results represent that each solar flare cycle (north, south and total hemisphere) and K-index activity data along with total time series data of both are regular dynamics and continue to long term in future. The complex of time series can be analyzed using Fractal dimension (local property) of the data while smoothness of time series be observe by Hurst Exponent (universal property). [ABSTRACT FROM AUTHOR]

BOH magnetometer was installed at Mt. Bohyun in 2007 and has provided continuous dataset for 3-axis geomagnetic field over the South Korea. We have calculated real-time K-index based on BOH magnetic field data using well-known FMI method. Local K-index is calculated eight times a day, per every three hours. To calculate K-index, it is critical to get the Quiet Day Curve (QDC). For QDC calculation, we take the previous one month’s average of H-component. In this paper, we compared four geomagnetic stations’ magnetic field data over South Korea and Japan and K-indices of each stations; Bohyun, Gangneung, Jeju, and Kakioka for two years data, 2011-2012. To investigate the difference depending on the latitude, longitude and local time in more detail, we compare K-index on International Quiet Days (IQDs) and International Disturbed Days (IDDs). As a result, we report the correlation between local K-indices are higher than those between Kp and local K-indices, and the correlation is much better after sunset than after sunrise. As the geomagnetic activity becomes stronger, the correlation between the local K-indices and global Kp-index become higher.

This paper describes a method to obtain local magnetic index, K, from the global index, Kp. Until now, however, for the cases of areas without magnetic observatories, to estimate the geomagnetic activity there, global indices were the only option. The methodology that we used to estimate local index was based on neural networks. This tool has a great potential for processing information from complex systems as in the case of the geomagnetic system. Local K index calculated with this method resulted to be a better option than directly using the global index Kp when we need an indicator of geomagnetic activity in a specific area. The best results of our method were for moderate and high geomagnetic activity, which are of major interest in Space Weather.

Local K-index is an indicator representing local geomagnetic activity in every 3 hour. For estimation of the local K-index, a reasonable determination of solar quiet curve (undisturbed daily variation of geomagnetic field) is quiet essential. To derive the solar quiet curve, the FMI method, which is one of representative algorithms, uses horizontal components (H and D) of 3 days magnetometer data from the previous day to the next day for a specific day. However, this method is not applicable to real time forecast since it always requires the next day data. In this study, we have devised a new method to estimate local K-index in near real-time by modifying the FMI method. The new method selects a recent quiet day whose Kp indices, reported by NOAA/SEC are all lower than 3, and replace the previous day and the next day data by the recent quiet day data. We estimated 2,672 local K indices from Gyeongzu magnetometer in 2003, and then compared the indices with those from the conventional FMI method. We also compared the K indices with those from Kakioka observatory. As a result, we found that (1) K indices from the new method are nearly consistent with those of the conventional FMI method with a very high correlation (R = 0.96); (2) our local K indices also have a relatively high correlation (R = 0.81) with those from Kakioka station. Our results show that the new method can be used for near real-time estimation of local K indices from Gyeongzu magnetometer.

Introduction: It is debatable whether pediatric patients diagnosed with arteriovenous malformations (AVMs) should be treated as adults. Several indexes to classify AVMs have been proposed in the literature, and most try to predict the outcome for each specific treatment. The indexes differ in the variables considered, but they are all based in adult populations. In this study, we analyzed the variables that influence the obliteration time and probability of occurrence in a Mexican pediatric population diagnosed with an AVM and treated with stereotactic radiosurgery (SRS). Methods: We analyzed 45 pediatric patients (<18 years) with a minimum follow-up of 10 months and a maximum of 112 months. We used logistic regression analysis and Kaplan-Meier curves to evaluate the influence of age, AVM volume, prescribed dose, minimum dose, maximum dose, time of follow-up, sex, previous hemorrhage, venous drainage, treatment technique, previous treatment and location. We also evaluated the predictive power of the following indexes: Spetzler-Martin, RBAS, or K index dose deviation. Results: We found that the radiation technique used may influence the obliteration occurrence (p = 0.057). The data suggests that circular arcs are a more efficient treatment technique than dynamic arcs. However, no relationship of dose or volume with treatment technique could be found. Obliteration was also dependent on follow-up time and after three years of follow-up, the obliteration probability decreases (p = 0.024). According to Kaplan-Meier analysis, the nidus obliteration time was related with the location according to the Spetzler-Martin index. If the nidus was located in a non-eloquent region, there was a tendency of a shorter obliteration time (p = 0.071). Conclusion: None of the previously proposed indexes for adults predict obliteration in this pediatric population. Treatment technique, eloquence and follow up time were the only variables that showed influence in obliteration. Since the highest probability of obliteration occurs during the first three years, if the nidus has not been obliterated after this time then another treatment option could be considered. [ABSTRACT FROM AUTHOR]