Sudden Commencement

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Geomagnetic sudden commencement at the dawn time dip equator

Geomagnetic sudden commencement at the dawn time dip equator

Waveform of geomagnetic sudden commencement (SC) on the ground depends on both latitude and local time (LT). Using high-resolution (1 s) geomagnetic field measurements obtained at Jicamarca (JIC, MAGLAT = 0 . 0 ◦ ) from 1998 to 2005, we examined the waveforms of 188 SC events and found that some of the SCs observed at nighttime (approx. 22–05 LT) and dawn time (approx. 05–07 LT) had a common observational feature, i.e., a positive impulse always appeared at the beginning of the main impulse of the SC, which led to these events show preliminary positive impulse (PPI) or ‘Stepwise’ structure in the waveforms. In particular, the occurrence rate of the PPI/Stepwise events at the dawn time was clearly higher than that at the nighttime. This is the first complete report of this observational feature for the SCs observed at the dip equator. Based on a comparison of our observations with the previously proposed model calculation of Kikuchi et al. (2001), we suggest that the PPI/Stepwise events observed at the dawn-time dip equator reflect the effects of the ionospheric currents (ICs) and field-aligned currents (FACs). We therefore argue that this observational result provides evidence for the validity of the model calculation.

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Characteristics of geomagnetic sudden commencement observed in middle and low latitudes

Characteristics of geomagnetic sudden commencement observed in middle and low latitudes

Characteristics of geomagnetic sudden commencement (SC) observed in middle and low latitudes are discussed on the basis of data analyses of magnetic variations and a numerical calculation. From the data analyses, it is found that a negative impulse is usually superposed on the main impulse of SC in H component just after its onset, at the stations in middle to high latitudes in the local time range from the morning to the early afternoon. The superposition of the negative impulse causes the decrease of SC amplitude in H component with increasing latitude in this area. The occurrence of the negative impulse does not seem to be dependent on geomagnetic activity. Examining a case study and a numerical analysis, it is suggested that this negative impulse is a signature of the magnetic variation due to the polar-originated ionospheric current system responsible for the main impulse of SC (DP MI ). The discussion includes the possible interpretation of PPI introduced by Kikuchi and Araki (1985) and the

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Historically largest geomagnetic sudden commencement (SC) since 1868

Historically largest geomagnetic sudden commencement (SC) since 1868

An anomalous geomagnetic sudden commencement (SC) occurred at 03:41 UT on 24 March 1991. It was character- ized by a large and short duration (1 to 2 min) magnetic pulse in the very initial stage of the SC which propagated from the day side to the night side (Araki et al. 1997). The H-component amplitude and rise time were measured as 202 nT and 28 s, respectively, by 1-s sampled values of Kakioka (27.5° gm. lat.) near 12-h LT. Since SCs with amp- litude larger than 100 nT is rare (less than 1% as shown later) at Kakioka and the rise time is mostly 3 to 4 min (Maeda et al. 1962), the amplitude of this pulse is anomal- ously large and the rise time is anomalously short. One- minute routine geomagnetic observations could not re- solve accurately such a rapid variation.

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Impact of interplanetary shock on the ULF wave activity: A case study of the storm sudden commencement on September 22, 1999

Impact of interplanetary shock on the ULF wave activity: A case study of the storm sudden commencement on September 22, 1999

We have analyzed short-period geomagnetic pulsations measured by the north-south chain of pulsation magne- tometers in Finland in association with the storm sudden commencement (SSC) recorded on September 22, 1999 at 12:22 UT. We observe that structured Pc 1 pulsations with amplitude modulation (modulation period is about 1000 seconds) were excited before the SSC whereas intense wave elements with rising frequency appear soon after SSC. It is concluded that the first effect is due to the interaction of the Earth’s magnetosphere with the interplanetary foreshock region. The second one is likely the result of modification of Pc 1 waves due to interaction between the magnetosphere and the shock front structure leading to compression of the magnetosphere during the initial phase of the magnetic storm.

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On latitudinal profile of Storm Sudden Commencement in H, Y and Z at Indian Geomagnetic Observatory chain

On latitudinal profile of Storm Sudden Commencement in H, Y and Z at Indian Geomagnetic Observatory chain

SSC (Storm Sudden Commencement) is one of the impor- tant aspects in Solar Terrestrial Relationships involving solar wind, Interplanetary Magnetic Field (IMF), Magnetosphere, Ionosphere and Equatorial Electrojet. The pressure of so- lar plasma on the earth’s magnetosphere under favourable conditions results in an increase of H field suddenly and si- multaneously at all the ground magnetic observatories in the world. The association of SSC amplitudes in H with the equatorial electrojet currents has been earlier reported in the literature (Rastogi et al., 1964; Rastogi, 1978 etc.). The lat- itudinal, longitudinal and solar cycle variations of SSC (H) at equatorial regions are reviewed by Rastogi (1993).

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Relationship between solar wind dynamic pressure and amplitude of geomagnetic sudden commencement (SC)

Relationship between solar wind dynamic pressure and amplitude of geomagnetic sudden commencement (SC)

On the ground, two pulses called the preliminary impulse (PI) and main impulse (MI) successively appear. Each of them is caused by the initial- and second-stage electric current system. The SC is characterized by this switching from PI to MI corresponding to switching of the magnetospheric electric field from the dusk-to-dawn to dawn-to-dusk direction. This is the general and fun- damental response of the magnetosphere to its sudden compression. Computer simulations show results con- sistent with this picture (e.g., Fujita et al. 2003a, b).

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Sudden releases of gases

Sudden releases of gases

Sudden releases of gases (short duration dangerous gas discharge during a terrorist attack or an accident) are greatly different from leaks form continuous gas sources (smoke from factory stacks, car exhausts). While for studying continuous gas sources corresponding experiment in wind tunnel suffices to be conducted only once for concentration calculation there must be carried out many replicas under the same release conditions to be able to evaluate puffs concentration.

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Sudden Unexpected Death in North Carolina (SUDDEN): methodology review and screening results

Sudden Unexpected Death in North Carolina (SUDDEN): methodology review and screening results

This medical record-based methodology is likely to lead to differing incidence rates than previous studies. An epidemiological study of sudden death states that limiting the de fi nition of sudden death to those that occur within the WHO de fi nition time restrictions might be too restrictive. 2 The SUDDEN study employs a medical record-driven case inclusion process that we believe will produce a more comprehensive registry of SUD cases than previous studies ( fi gure 2). Of the 100 participants who experienced unwitnessed deaths, it was unknown when 84 were last seen alive (table 2). The Oregon study would exclude these 84 participants based on the WHO de fi nition. 23 We exclude participants over 65 years old and those in nursing facilities, presuming these groups have an increased likelihood of experien- cing an expected death, to focus our study on a younger cohort that are likely victims of an unexpected event. 24 This age limit accounted for 42% of our exclusions ( fi gure 2). Additionally, we are inclusive of cases of trauma in which the trauma may have been the result of a cardiac event, as shown by high percentage of external or unknown causes of death (30%). The screening cri- teria outlined above will allow us to describe SUD in a clinically meaningful group.

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Breastfeeding Patterns Of Postnatal Mothers And The Effects On The Health Status Of Their Infants.

Breastfeeding Patterns Of Postnatal Mothers And The Effects On The Health Status Of Their Infants.

This study investigated the breastfeeding patterns of postnatal mothers and the effects on the health status of their infants. 299 postnatal mothers who visited infant welfare clinics in the South-East zone of Nigeria along with their infants were selected for the study using convenient sampling technique. One research question and two null hypotheses were formulated to guide the study. Questionnaire on patterns of Breastfeeding by postnatal mothers (QPBF) and Checklist on Health status of infants with varied breastfeeding patterns (CHSIVBP) were used for data collection in the study. Frequency distribution and percentages were used to answer the research question while chi-square test and Spearman Rank correlation coefficient were adopted in testing the null hypotheses at 0.05 level of significance. The result revealed that infants of most of the postnatal mothers with varied breastfeeding patterns had normal nutritional status and general body system with low rates of malnutrition. Time of commencement of breastfeeding was found not to significantly influence the health status of the infants, and there was no significant relationship between the breastfeeding patterns of the postnatal mothers and the health status of their infants. Keywords: Breastfeeding patterns, Health status, Infants, Postnatal mothers.

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1. —(1) This Order may be cited as the Housing and Regeneration Act 2008 (Commencement

1. —(1) This Order may be cited as the Housing and Regeneration Act 2008 (Commencement

Article 4 provides that on or after the commencement date the 1983 Act, as amended by section 318 of the 2008 Act and the Mobile Homes Act 1983 (Amendment of Schedule 1 and Consequential Amendments) (England) Order 2011, applies to existing agreements in the same way it applies to a new agreement entered into on that date.

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Exploring the disconnections: student interaction with support services upon commencement of distance education

Exploring the disconnections: student interaction with support services upon commencement of distance education

While provision of appropriate supports in the first year of study has been found to have a positive effect on student success, supports targeting online and distance learners are often applied in a “goulash approach.” Against this backdrop, the research investigated the experiences of first-time distance learners with a view to informing the future design of supports during the early stages of the study lifecycle. The study was framed around Design-Based Research involving a mixed method approach over three phases: a stocktake of services designed to support distance learning; a pre- and post-semester survey of first-time distance learners; and a video diary phase that gathered the lived experiences of 20 students upon commencement of their study. Triangulated results of the three phases highlight a disconnection between institutional support services and the majority of first-time distance learners who demonstrated a self-sufficient, lone wolf approach to learning.

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Extension of time in commencement of arbitration proceedings

Extension of time in commencement of arbitration proceedings

The court has the power to extend time for commencement of the arbitration proceedings, if it is of the opinion that in the circumstances of the case „hardship would otherwise be caused‟ and notwithstanding that the time so fixed in the arbitration agreement has expired. In that provision, the court‟s power to extend time is without prejudice to any written law limiting the time for the commencement of arbitration proceedings. Under the Law of Limitation Act which governs the limitation of claims, the word “arbitration" is defined to mean arbitration on a submission or under any written law. Section 40 of the Law of Limitation provides that the Act applies to arbitrations in the same manner as it applies to other proceedings. For the purpose of limitation, the law considers that where a submission contains a term that no cause of action shall accrue in respect of a matter, the cause of actions hall accrues in respect of any such matter at the time when it would have accrued but for the term in the submission. The Law of Limitation provides further under section 40(3) as follows:-

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Timing of commencement of maintenance dialysis and mortality in young and older adults in Singapore

Timing of commencement of maintenance dialysis and mortality in young and older adults in Singapore

average of 147 days earlier in 2007 than in 1997, especially in the very elderly (75 years and older) in whom initiation was 233 days earlier [4]. Similarly, average eGFR at dialysis initiation rose from 7.9 to 8.6 mL/min/1.73m 2 between 1999 and 2003 [3]. The upward trend could be a conse- quence of differences in guidelines among professional societies with varying recommendations for consideration of dialysis, e.g., eGFR < 15 or <20 mL/min/1.73m 2 [5 – 7]. However, dialysis is expensive and has been shown to be associated with reduced quality of life thereby mandating clear evidence of health benefit with early commencement at higher eGFR [8]. Evidence supporting improved nutri- tional state or decreased risk of hospitalization or mor- tality attributable to early initiation of dialysis is limited and controversial [9 – 11].

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On the establishment of the lowest astronomical tide for marine parcel commencement in peninsular Malaysia

On the establishment of the lowest astronomical tide for marine parcel commencement in peninsular Malaysia

The term cadastre has not often been used in the context of the marine environment (Fowler and Treml, 2001). Cadastre is a system containing a record of interesting land such as right, restrictions and responsibility meanwhile marine cadastre is a cadastre system in the context of the marine administration. The prerequisite for initiate administration of marine environment in a country is to clearly identify the determination of low water mark, in order for it to define the commencement of marine cadastre. Moreover, marine cadastre is quite different situation as that on the land. The marine cadastre concept will be successful if supported by the right law and regulation on marine management and practice for marine parcel (Ashraf et al., 2013). To certify that parcels are uniquely positioned and identified, datums and map projections used in marine spaces have to be recognized and harmonised (Ng’ang'a et a l, 2004). Thus both horizontal and vertical datum is important to be defined.

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SIDS and Other Sleep-Related Infant Deaths: Evidence Base for 2016 Updated Recommendations for a Safe Infant Sleeping Environment

SIDS and Other Sleep-Related Infant Deaths: Evidence Base for 2016 Updated Recommendations for a Safe Infant Sleeping Environment

Approximately 3500 infants die annually in the United States from sleep- related infant deaths, including sudden infant death syndrome (SIDS), ill-defi ned deaths, and accidental suffocation and strangulation in bed. After an initial decrease in the 1990s, the overall sleep-related infant death rate has not declined in more recent years. Many of the modifi able and nonmodifi able risk factors for SIDS and other sleep-related infant deaths are strikingly similar. The American Academy of Pediatrics recommends a safe sleep environment that can reduce the risk of all sleep-related infant deaths. Recommendations for a safe sleep environment include supine positioning, use of a fi rm sleep surface, room-sharing without bed-sharing, and avoidance of soft bedding and overheating. Additional recommendations for SIDS risk reduction include avoidance of exposure to smoke, alcohol, and illicit drugs; breastfeeding; routine immunization; and use of a pacifi er. New evidence and rationale for recommendations are presented for skin-to-skin care for newborn infants, bedside and in-bed sleepers, sleeping on couches/ armchairs and in sitting devices, and use of soft bedding after 4 months of age. In addition, expanded recommendations for infant sleep location are included. The recommendations and strength of evidence for each recommendation are published in the accompanying policy statement, “SIDS and Other Sleep-Related Infant Deaths: Updated 2016 Recommendations for a Safe Infant Sleeping Environment, ” which is included in this issue.

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Factors affecting commencement and cessation of smoking behaviour in Malaysian adults

Factors affecting commencement and cessation of smoking behaviour in Malaysian adults

Results: Males had a much higher prevalence of the habit (61.7%) as compared to females (5.8%). Cessation was found to be most common among the Chinese and those regularly consuming alcoholic beverages. Kaplan-Meier plot shows that although males are more likely to start smoking, females are found to be less likely to stop. History of betel quid chewing and alcohol consumption significantly increase the likelihood of commencement (p < 0.0001), while cessation was least likely among Indians, current quid chewers and kretek users (p < 0.01). Conclusions: Gender, ethnicity, history of quid chewing and alcohol consumption have been found to be important factors in smoking commencement; while ethnicity, betel quid chewing and type of tobacco smoked influences cessation.

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Sudden Storm Commencement of 21 ST January 2005 at Conjugate Location

Sudden Storm Commencement of 21 ST January 2005 at Conjugate Location

The onset of a magnetic storm is often characterized by a global sudden increase in H, which is denoted by equatorial Dst the disturbance field, which is axially symmetric with respect to the dipole axis, and which is regarded as a function of storm-time. If an index monitoring the Dst in H is derived continuously as a function of UT, this variation will clearly indicate the occurrences of magnetic storms and their severity when they occur. A major magnetic storm occurs when the IMF experiences (more than 3h) an intense (more than 10 nT) southward component [Gonzalez and Tsurutani, 1987].

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