What Is a Developmental Delay in Young Children? Developmental delay is when your child lags behind their peers in one or more areas of emotional, mental, or physical growth. In radio and television, broadcast delay is an intentional delay when broadcasting live material, technically referred to as a deferred live.Such a delay may be to prevent mistakes or unacceptable content from being broadcast. Longer delays lasting several hours can also be introduced so that the material is aired at a later scheduled time (such as the prime time hours) to maximize viewership. What Is a Developmental Delay in Young Children? Developmental delay is when your child lags behind their peers in one or more areas of emotional, mental, or physical growth. Stay connected with service delays and disruptions When the unexpected happens, communication is key. Uncontrollable events like weather or natural disasters.
The importance of successful vaccination strategies in controlling the covid-19 pandemic cannot be overstated and should be vigorously endorsed. Equally critical is that vaccines' proven to be effective in a particular dosing schedule are not altered without solid scientific support or evidence. Two covid-19 vaccines, (from Pfizer/BioNTech and AstraZeneca/Oxford) recently approved for emergency use in the UK have a defined time scheduled two doses for use. Due to the accelerating pandemic and a desire to maximise the numbers in the population to receive a first dose vaccine, the Joint Committee on Vaccines and Immunization (JCVI) has proposed changing the dose schedules by considerably extending time to the second booster dose. The proposal has been supported by the UK Chief Medical Officers (CMOs) who indicated there are vaccine shortages across the UK. This is disputed by vaccine manufacturers.
The Pfizer/BioNTech vaccine is the first human mRNA vaccine evaluated in a phase 3 clinical trial. The study was a well-designed, prospective randomised controlled trial with blinded endpoint assessment. [1] It was well powered, reporting on 37,706 individuals at 152 sites in six countries who received vaccine or placebo and had median follow-up of 2 months. The overall results showed an efficacy of 95% reduction in covid-19 cases at least seven days after the second dose, which was delivered to a scheduled 21-day interval between the 1st and 2nd dose. Sub-group analyses confirmed similar vaccine efficacy among subgroups including patient age.
The JCVI advice and the CMO's decision to delay the second dose to between 4-12 weeks is not based on data from the trial, but on an assumption of what would have happened if the second dose hadn't been given at 21 days. While assumptions can be useful for generating a hypothesis, alone they are not a sufficient reason to alter a known effective dosing regimen.
There are also no data on how long a first single dose of the mRNA generated immunogen (the virus Spike protein) induces a clinically effective immune response, comprising T cells, B cells, and their memory cells. [2] A crucial point is that the Pfizer vaccine uses mRNA. Non-replicating mRNA (basic structure used in the two covid-19 vaccines- Pfizer/BioNTech and Moderna) after injection into the body becomes quickly degraded by extra and intracellular enzyme systems (RNAases). Modifications have been introduced, to improve the delivery and survival of the mRNA vaccines, including as in the Pfizer/BioNTech vaccine, enveloping the mRNA in lipid nanoparticles (LNP-mRNA). How well the LNP-mRNA survives after a 1st injection and induces durable human immune responses is unknown. [3-5] Animal models using LNP-mRNA vaccines against the virus show that ~28 days after a 1st injection, correlates of virus neutralising antibody production fall off markedly (suggesting limited survival and stimulation by the vaccine mRNA and its' encoded Spike immunogen). However, the specific anti-viral immune response was strongly boosted with a 2nd injection of vaccine. [6] This raises concerns that extending a 2nd injection out to beyond 28 days could compromise vaccine efficacy. Human studies are urgently needed, ideally before pursuing the delayed 2nd dose strategy. The time interval for a mRNA booster may be very critical for getting the best sustained immune response. mRNA vaccines have never been used in late stage human trials before 2020 and the only data we have are from the Pfizer/BioNTech and the Moderna (another mRNA vaccine) studies, which use different vaccines at different concentrations.
Furthermore, given that the Pfizer/BioNTech vaccine is scheduled to be delivered to 3-10 million vulnerable adults or health and social care workers exposed to high levels of risk, the JCVI/CMOs appear to be advocating what could prove to be a major change with attendant clinical risk (eg less efficacy than that generated by Pfizer/BioNTech study). The MHRA has approved and international expert bodies have advised using the existing study dosing schedule. The Centre for Disease Control in the USA has stated that for both mRNA vaccines (Pfizer/BioNTech & Moderna) 'The second dose should be administered as close to the recommended interval as possible' – i.e. 21 days and 28 days respectively. [7] The World Health Organization has also advised that the Pfizer/BioNTech vaccine should be given 'according to the following schedule: a single dose followed by a second dose 21 days later.' [8]
Maximising coverage with the 1st dose as intended by the CMOs could come at increased risk to already high risk/priority groups. At a minimum, if the UK remains intent on pursuing this time extension to the second dose, the following should be implemented:
Firstly, the second dose should continue to be provided at 21 days until the MHRA and/or JCVI make the data on which the JCVI recommendation is based publically available for independent scientific review.
JCVI's hypothesis that 50-60% efficacy with one dose is better than 95% efficacy for half the number of individuals with the MHRA approved dosing is, as far as we know, based on an assumption. However, if following a single dose there was a substantial decrease in efficacy during days 21-84, then the number of lives saved and hospital admissions avoided may be less than with the 21-day second dose schedule, for which we have efficacy results. Just as critical, the secondary immune response from a delayed dose at 84 days and any impact on the duration of immunity is unknown.
Secondly, if the delay in the second dose is implemented then rigorous RCTs comparing the 21-day and delayed second dosing schedule should be conducted to rapidly ensure evidence-based future vaccination policy.
The vaccine used in the Oxford/AstraZeneca study is a different type of vaccine (viral vector DNA) for which there are prior data from other similar vaccines. [8,9] In these circumstances, there is a valid argument to support delaying the second dose of this vaccine if there is not sufficient supply of the vaccine and the balance of public health risks warrants this. If JCVI's advocacy for a dose delay has been based on unpublished research data and current modelling, such data should be immediately made available in the public domain for adequate peer reviewed scrutiny.
John FR Robertson, Professor of Surgery & Consultant Surgeon, University of Nottingham.
Herb F Sewell, Emeritus Professor of Immunology & Consultant immunologist, University of Nottingham.
Marcia Stewart, Social Care professional & emeritus academic, De Montfort University.
Denise Kendrick, Professor of Primary Care Research and General Practitioner, University of Nottingham.
Raymond M Agius, Emeritus Professor of Occupational Medicine, University of Manchester, Manchester.
Declaration of interest: All authors are current or intended recipients of covid-19 vaccines. HFS has served on UK Medicines Commission from 2002-2006. He has a doctor as a family member.
Acknowledgement: Professor Sheila M. Bird OBE FMedSci FRSE Formerly Programme Leader at MRC Biostatistics Unit, Cambridge Institute of Public Health; for her helpful comments and discussions about prospective RCTs and delayed covid-19 vaccine doses (see reference 10).
References:
(1) Polak FP, Thomas SJ, Kitchin N et al Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine NEJM 2020 DOI: 10.1056/NEJMoa2034577
(2) Sewell HF, Agius RM, Kendrick D, Stewart M Covid-19 vaccines: delivering protective immunity: Evidence supports both T and B cell responses to the three leading vaccines BMJ 2020;371:m4838 http://dx.doi.org/10.1136/bmj.m4838
(3) Pardi N., Hogan M.J., Porter F.W., Weissman D. mRNA vaccines—A new era in vaccinology. Nat. Rev. Drug Discov. 2018;17:261–279. doi: 10.1038/nrd.2017.243
(4) Xu S, Yang K, Li R, Zhang L. mRNA Vaccine Era-Mechanisms, Drug Platform and Clinical Prospection. Int J Mol Sci. 2020 Sep 9;21(18):6582. doi: 10.3390/ijms21186582. PMID: 32916818; PMCID: PMC7554980.
(5) Chung JY, Thone MN, Kwon YJ. COVID-19 vaccines: The status and perspectives in delivery points of view [published online ahead of print, 2020 Dec 21]. Adv Drug Deliv Rev. 2020;S0169-409X(20)30282-9. doi:10.1016/j.addr.2020.12.011
(6) Lederer K, Castaño D, Gómez Atria D, Oguin TH 3rd, Wang S, Manzoni TB, Muramatsu H, Hogan MJ, Amanat F, Cherubin P, Lundgreen KA, Tam YK, Fan SHY, Eisenlohr LC, Maillard I, Weissman D, Bates P, Krammer F, Sempowski GD, Pardi N, Locci M. SARS-CoV-2 mRNA Vaccines Foster Potent Antigen-Specific Germinal Center Responses Associated with Neutralizing Antibody Generation. Immunity. 2020 Dec 15;53(6):1281-1295.e5. doi: 10.1016/j.immuni.2020.11.009. Epub 2020 Nov 21. PMID: 33296685; PMCID: PMC7680029.
Dll link. A DLL is a library that contains code and data that can be used by more than one program at the same time. For example, in Windows operating systems, the Comdlg32 DLL performs common dialog box related functions. Each program can use the functionality that is contained in this DLL to implement an Open dialog box.
(7) https://www.cdc.gov/vaccines/covid-19/info-by-product/clinical-considerations.html Site accessed 1st January 2021 last reviewed: December 30, 2020 Content source: National Center for Immunization and Respiratory Diseases)
(8) https://apps.who.int/iris/bitstream/handle/10665/338096/WHO-2019-nCoV-vaccines-SAGE_evaluation-BNT162b2-2020.1-eng.pdf
(9) Voysey M, Clemens SAC, Madhri SA et al Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK Lancet 2020 https://doi.org/10.1016/S0140-6736(20)32661-1
(10) Bird S M, MHRA's Public Assessment Report Authorisations for Temporary Supply (under regulation 174 of the Human Medicines Regulation); recommendations by Joint Committee for Vaccination and Immunization. https://www.sciencemediacentre.org/expert-comment-on-whether-giving-two-doses-of-covid-vaccine-separated-by-a-longer-period-is-sensible/
In radio and television, broadcast delay is an intentional delay when broadcasting live material, technically referred to as a deferred live. Such a delay may be to prevent mistakes or unacceptable content from being broadcast. Longer delays lasting several hours can also be introduced so that the material is aired at a later scheduled time (such as the prime time hours) to maximize viewership. Tape delays lasting several hours can also be edited down to remove filler material or to trim a broadcast to the network's desired run time for a broadcast slot, but this is not always the case.
Usage[edit]
A short delay is often used to prevent profanity, bloopers, nudity, or other undesirable material from making it to air, including more mundane problems, such as technical malfunctions (an anchor's lapel microphone goes dead). In that instance, it is often referred to as a 'seven-second delay' or 'profanity delay'. Longer delays, however, may also be introduced, often to allow a show to air at the same time for the local market as is sometimes done with nationally broadcast programs in countries with multiple time zones. Considered as time shifting, that is often achieved by a 'tape delay', using a video tape recorder, modern digital video recorders, or other similar technology.
Tape delay may also refer to the process of broadcasting an event at a later scheduled time because a scheduling conflict prevents a live telecast, or a broadcaster seeks to maximize ratings by airing an event in a certain timeslot. That can also be done because of time constraints of certain portions, usually those that do not affect the outcome of the show, are edited out, or the availability of hosts or other key production staff only at certain times of the day, and it is generally applicable for cable television programs.
In countries that span multiple time zones and have influential domestic eastern regions, such as Australia, Canada, Mexico and the United States, television networks usually delay the entirety of their schedule for stations in the west, so prime time programming can be time shifted to air in local primetime hours to improve accessibility and viewership. Although Mexico and Canada have now regularly televised their live programs in real time simultaneously across all of their territories, in the U.S., 'east' feeds usually target the Eastern and Central time zones, while 'west' feeds are usually oriented towards the Pacific time zone. As a result, until today, many live programs, such as music and talent competition shows, are usually tape delayed for the western half of the country and aired as-live (although they may include edits to streamline the broadcast or resolve technical faults). Australian network television schedule is largely patterned from the U.S. format.
In countries that span multiple time zones and are the most populous in their western or central regions, like Brazil, Russia and Indonesia, all television schedules nationwide are simultaneous with their broadcast sources, enabling full nationwide live telecasts regardless of time zones (although Russia conducts separate live primetime newscast versions for each range of time zones in that country). The continents of Europe and Africa, which both fall in the same range of time zones, are receptive to each other's live telecasts, while most of Asia from India eastwards, which includes China alongside the most populous time zone in the world, also receive simultaneous live telecasts within those cluster of regions.
International tape delays of live global events, intended by major television networks, dominated world television until the early 2010s. For example, during the Sydney Olympics in 2000 and the Beijing Olympics in 2008, daytime events were occurring at early morning hours in the Americas, Africa, and Europe but were aired in the afternoon and evening hours live entirely in Asia, Australia, and Oceania. That made some broadcasters show high-profile events twice (live and then rebroadcast during prime time), but others withheld the same event to be broadcast solely during prime time. Often, tape-delaying of those events would mean editing them down for time considerations, highlighting what the broadcaster feels are the most interesting portions of the event, or advertising, resulting to reduced desired TV coverage for the given multiple sporting events.
However, since many live events became available via social media in the late 2000s, tape delays have become increasingly irrelevant because of live television's resurgence as a broadcast format. Since the mid-2010s, several high-profile entertainment programs with huge live global audiences like the Academy Awards, Primetime Emmy Awards and Grammy Awards, yearly specials like the Miss Universe and Miss World pageants, and major sporting events like the Olympic Games, FIFA World Cup and the National Football League's Super Bowl, air to totality live on both television and the internet virtually all across the world's time zones in and out of their countries of origin, with mandated prime time rebroadcasts (featuring edits as desired by broadcasters) for regions that previously and solely relied on delayed telecasts on prime time among these otherwise live events.
History[edit]
The radio stationWKAP in Allentown, Pennsylvania, introduced a tape delay system consisting of an external playback head, which was spaced far enough away from the record head to produce a six-second delay.[1] A system of rollers guided the tape over the playback head before it wound up on the take up reel. This system was introduced in 1952, when WKAP started a talk show called Open Mic. It is believed that this was the first time a telephone call-in show was broadcast with the telephone conversation 'live' on the air. The FCC rules at the time prohibited the broadcasting of a live telephone conversation. However, there was no rule prohibiting a taped playback of a telephone call, provided that a 'beep' tone was heard by the caller every 15 seconds so that the caller knew he was being recorded. The six-second delay constituted a 'taped' telephone conversation, thus complying with FCC regulations, that being a legal fiction.
The broadcast profanity delay was invented by C. Frank Cordaro (July 13, 1919 – February 20, 1997), who was Chief Engineer of WKAP during the 1950s and early 1960s. Ogden Davies, then-General Manager of WKAP, assigned Cordaro the task of developing a device whereby profanity during a 'live' conversation could be deleted by the radio talk show host before it was broadcast. This new device was to be used on the Open Mic radio talk show. The device Cordaro developed was the first tape delay system. WKAP was one of several stations owned by the Rahal brothers of West Virginia (later Rahal Communications). First tested and used at WKAP, this tape system for broadcast profanity delay was then installed at the other Rahal-owned radio stations. From the Rahal brothers' stations, the broadcast profanity delay went into common usage throughout the US.[citation needed]
John Nebel, who began a pioneering radio talk show in New York City in 1954, was one of the early users of a tape delay system that was invented by his engineer, Russell Tinklepaugh.[2] Another announcer who was said to use a tape-delay was talk show pioneer Jerry Williams at WMEX in Boston in the late 1950s.
Computerized delay[edit]
In 1977, the capacity of RAM (random-access memory) had reached 16 kilobits per chip, enough to think about using computerized digital audio means to create a sufficient delay for content deletion. By storing audio digitally, it was possible to move a 'virtual tape head' along recorded audio. Eventide, Inc. created the first digital broadcast delay for this purpose. The device (known colloquially as a 'dump box') had a large 'DUMP'/'DELAY DUMP' button that would bring the delay to zero, thus removing unwanted segments. In addition to this convenience, it would also 'rebuild' the delay time by unnoticeably lengthening the normal pauses in spoken material. Thus, a minute or so later, the broadcaster would again have full delay, often leaving the listener unaware that material had been deleted.
In modern systems, a profanity delay can be a software module manually operated by a broadcast technician that puts a short delay (usually, 30 seconds) into the broadcast of live content. This gives the broadcaster time to censor the audio (and video) feed. This can be accomplished by cutting directly to a non-delayed feed, essentially jumping past the undesired moment (something that can be quite jarring to a viewer or listener). In other cases, dedicated hardware units similar to the original digital unit but with improved quality and editing capability can be used. These products can even 'build up' delay with difficult program material such as music. Alternatively, a bleep noise or other substitute sound can be inserted. This is more difficult to do with live content, however, and more often appears on recorded material.
See also[edit]
A Delay Caused The Plane To Crash
References[edit]
- ^Elly, Wally (2006-09-20). 'In local radio, change is common - with one exception'. The Morning Call. Retrieved 2016-08-16.
- ^Tom Tiede. 'Talk-Jockey Jimmy Hits the Air'. Portsmouth (NH) Times, March 4, 1977, p. 4.
External links[edit]
A Delay Is Not A Denial
