A new paper about the inner ear shows an additional level of organization and architecture that increases sensitivity and frequency discrimination.The “organ of Corti” is not a keyboard instrument in a European cathedral, but it might as well be. It’s a keyboard of sorts, composed of rows of ‘hair cells” inside that tiny snail-like coil in the inner ear, the cochlea. Physiologists have known for a long time that hair cells along its coiled-up track, called the basilar membrane, respond to different frequencies. There are two rows of hair cells, inner and outer. According to Massachusetts Eye and Ear Infirmary, “the ‘outer hair cells’ act as micromotors that amplify incoming sound, and the ‘inner hair cells’ act to sense and transmit information about the sound to the brain.” The hair cells, therefore, play the starring roles in hearing. But do they work alone or in concert? (Pun intended.)The field of cochlear mechanics has been undergoing a revolution due to recent findings made possible by advancements in measurement techniques. While it has long been assumed that basilar-membrane (BM) motion is the most important determinant of sound transduction by the inner hair cells (IHCs), it turns out that other parts of the sensory epithelium closer to the IHCs, such as the reticular lamina (RL), move with significantly greater amplitude for weaker sounds. It has not been established how these findings are related to the complex cytoarchitecture of the organ of Corti between the BM and RL, which is composed of a lattice of asymmetric Y-shaped elements, each consisting of a basally slanted outer hair cell (OHC), an apically slanted phalangeal process (PhP), and a supporting Deiters’ cell (DC). Here, a computational model of the mouse cochlea supports the hypothesis that the OHC micromotors require this Y-shaped geometry for their contribution to the exquisite sensitivity and frequency selectivity of the mammalian cochlea.In a piano, it’s not just the keys and hammers that make sound. The whole instrument is involved: the sounding board, the pedals, the dampers, and everything else. The keys and action are tied into this vibrating framework. In a similar way, the hair cell bundles do not act in isolation. A new paper in PNAS (quoted above) explains that “Cochlear amplification and tuning depend on the cellular arrangement within the organ of Corti.” In short, the whole inner architecture is involved in hearing, not just the hair cells.Credit: PNAS, Massachusetts Eye & EarWhile the near-crystalline structure of the organ-of-Corti cytoarchitecture in the mammalian cochlea has been known for some time, its functional consequences on hearing remain to be established. The present computational-modeling studies show that individual outer hair cells (OHCs) can work together to produce high hearing sensitivity and frequency selectivity because of the overlapping asymmetrical Y-shaped structures that they form with the Deiters’ cells (DCs) and phalangeal processes (PhPs). Altering the geometry and material properties of these structures reveals that all three components have a profound effect on basilar-membrane and reticular-lamina amplification and tuning. One implication is that the DCs and PhPs are not just supporting structures, but that they must also be properly restored in emerging therapies to regenerate OHCs.An illustration in the press release shows a diagram of the model of this Y-shaped structure, looking like a row of “Y” letters arranged along their sides. Physiologists had hoped that techniques to regenerate just the hair cells might restore hearing. Now, however, this team has demonstrated that the “sounding board” needs to be restored as well. Animations within the PNAS paper show waves traveling along this architecture, looking like waves along a series of closely-spaced power poles. Alterations to this structure compromise the sensitivity of hearing.In addition, there are two domains of fluid inside the organ of Corti that play critical roles in hearing. Their viscous properties and pressures must be finely tuned to the architecture. The organization extends all the way down to individual proteins within the hair cells: “Prestin proteins in the OHC plasma membrane provide a piezoelectric effect, such that depolarization causes axial contraction and hyperpolarization causes axial expansion,” they write. The senior author says, “Our work suggests that, in order for humans to hear well, the outer hair cells in the cochlea not only need to be in good working order, but also need to be connected to other nearby cochlear structures in a very particular way.”The inner ear demonstrates a remarkable example of irreducible complexity. As masterfully organized as the cochlea is, it’s part of another irreducibly complex system in the ear, starting with the outer ear, the ear canal, the eardrum, the bones of the middle ear, the cochlea, and the auditory nerve. Even then, signals to the brain signify nothing unless the brain has the “software” to interpret the sounds.The authors never mentioned “evolution” in the paper or in the press release. The closest word was “revolution,” as in “The field of cochlear mechanics has been undergoing a revolution” in understanding the remarkable architecture by which we hear pressure waves emanating in the world around us. 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Kuala Lumpur-based AirAsia is having another tilt at a joint venture in Vietnam that will pit it against the well-established operations of Jetstar Pacific and VIetJet. Wholly-owned AirAsia subsidiary AirAsia Investment Limited signed an agreement on March 30 week with Gumin Company Limited, the Hai Au Aviation Joint Stock Company and their owner Tran Trong Kien to establish a budget carrier in the fast-growing market.The budget carrier will own 30 per cent of the joint venture which plans to start flying in 2018, subject to Vietnam’s often difficult regulatory process.Vietnam’s aviation market has been growing at a healthy clip and Bloomberg estimates the growth is three times the rate in other Southeast Asian countries.Government statistics show there were 52.2 million air travellers in Vietnam in 2016, an increase of 29 per cent year-on-year, with 28 million flying domestically. The International Air Transport Association has predicted there will be 112 million new passengers in Vietnam over the next two decades.This is AirAsia’s third attempt to get a foothold in Vietnam as part of its strategy to establish an Asian network and the CAPA Centre for Aviation believes being late to the market will make the job more difficult. “ AirAsia was initially partnered with VietJet Air but the partnership was dissolved prior to VietJet commencing operations in late 2011,’’ CAPA said.“The market has since more than doubled in size, and Vietnam has emerged as Southeast Asia’s fastest growing market. “While there is further growth potential, the LCC incumbents VietJet and Jetstar Pacific have first mover advantage, and infrastructure constraints could make it difficult for any new entrant to establish a significant presence.”AirAsia will also need to overcome regulatory hurdles.”Known for publicity stunts involving bikini-clad girls, VietJet launched in 2011 as Vietnam’s first privately owned “new age” carrier and publicly listed earlier this year.It operates almost 40 Airbus A320 and A321 aircraft to about 60 domestic and international destinations with ports in Thailand, Singapore, South Korea, Taiwan, Malaysia, China, Japan, Hong Kong and Myanmar. It hopes to have a fleet of 200 aircraft by 2023 and last year placed an order with Boeing for 100 737 MAX jets with a list price of $US11.3 billion.Jetstar Pacific launched in 2008 and now flies to 16 domestic and international destinations with a fleet of 10 Airbus A320 aircraft. It has plans to expand its fleet to 30 A320s.Australia’s Jetstar Group owns 30 per cent of the airline while Vietnam Airlines, which is also a codeshare partner with Jetstar, owns the remainder.Jetstar’s Australian long-haul operations will move in May to reconnect with its sister airline when it resumes flights to Ho Chi Minh City.Starting May 10, Jetstar will operate Boeing 787 Dreamliner services three times weekly from Melbourne and four times weekly from Sydney.Jetstar Group chief executive Jayne Hrdlicka in January described Vietnam as one of the fastest growing holiday destinations in South East Asia.“Vietnam has the potential to become as popular as Bali or Thailand for Australian travellers,” Hrdlicka said. “Vietnam is well known for its rich culture, vibrant cities, beaches and cuisine, and travellers can take advantage of the wide range of experiences the region has to offer.“We expect our low fares and direct flights will generate even more demand for holidays to Vietnam.’’Jetstar International first flew to Vietnam from Australia a decade ago.
Share Facebook Twitter Google + LinkedIn Pinterest Twenty county Farm Bureaus were honored for outstanding programming over the past year. Their recognition as Achievement Award winners came during the 99th annual meeting of Ohio Farm Bureau, Dec. 6 – 8 in Columbus.The winning counties represent excellence in local activities that support Farm Bureau’s strategic efforts. Those include programs to strengthen the organization and build membership, affect public policy, promote agriculture and enhance the organization’s relationship with long-standing partner Nationwide.Additionally, Collaboration Awards were presented to groups of counties that worked together to create unique and effective programming.The award applications were judged by volunteer Farm Bureau members, and counties were placed in four divisions based on the size of their membership.During the awards ceremony, Ohio Farm Bureau Executive Vice President Adam Sharp said, “Every member in the county plays an important part in these programs’ success, from volunteering to serve on action teams and committees, to the planning of the various activities, to talking with neighbors about the issues that impact agriculture and how important it is for all of us to keep Farm Bureau and agriculture strong.”The top counties were:Carroll — Substance Abuse Prevention/Got Your Back programCrawford — Focus of Your Future programFayette — Farm to Fork Charity Event and War on DrugsFulton — Ag AdventuresGreene — Celebrating Ohio’s Apple HarvestHamilton — Fall Ag DayHancock — Kids Dream DayHarrison — Farm Bureau/FFA Career Day and Family Chicken BBQHenry — STEM Teacher Presentation programHolmes — Harvest for Hunger programJackson-Vinton — Agriculture Experience DayLake — Comprehensive Membership CampaignLogan — Farm to Fork eventMedina — Agriculture Acres projectMercer — Agriculture in Your Backyard programPutnam — Shaping the Future Ag TourRichland — Farm to Plate eventStark — County Fair DisplayTuscarawas — Weeding Out Substance Abuse in Rural Ohio programWashington — Farm City DayCollaboration awards were presented to:Ashtabula, Geauga, Lake, Trumbull and Mahoning counties — Livestock Transit Member BenefitCarroll and Tuscarawas counties — Weeding Out Substance Abuse in Rural Ohio/Farm Bureau’s Got Your Back CampaignCrawford and Wyandot counties — Focus on the Future event.
IT + Project Management: A Love Affair 3 Areas of Your Business that Need Tech Now fredric paul Cognitive Automation is the Immediate Future of… Tags:#BYOD#Survey Massive Non-Desk Workforce is an Opportunity fo… Related Posts The growing trend of Bring Your Own Device (BYOD) to the workplace is having dramatic effects on corporate IT plans, policies and staffing. That’s the conventional wisdom, anyway.But ReadWrite wants to know what’s really happening. How is your company dealing with employees using their own devices for work purposes? Why did you decide to do it? What are your biggest concerns? How is it working out so far?That’s why we put together this little 9-item questionnaire: ReadWrite BYOD Survey. (There are also a few demographic questions at the end, so we can better analyze the results.)Once we have enough responses, we’ll put together a post detailing the insights we gained, so if you’d like to share additional BYOD thoughts in the comments, we’re all ears.Take the ReadWrite BYOD Survey now!Image courtesy of Shutterstock.
Trending Articles PLAY LIST 00:50Trending Articles00:50Trending Articles00:59Sports venues to be ready in time for SEA Games01:29Police teams find crossbows, bows in HK university01:35Panelo suggests discounted SEA Games tickets for students02:49Robredo: True leaders perform well despite having ‘uninspiring’ boss02:42PH underwater hockey team aims to make waves in SEA Games01:44Philippines marks anniversary of massacre with calls for justice01:19Fire erupts in Barangay Tatalon in Quezon City It might have been that middle blocker Celine Domingo used to don the red of the Lady Warriors, but skipper Bernadeth Pons echoed her mentor’s words.Pons admitted what they displayed in their victory over UE, 25-20, 25-17, 24-26, 25-22, wasn’t their best and they vow to do better in the future games.FEATURED STORIESSPORTSWATCH: Drones light up sky in final leg of SEA Games torch runSPORTSLillard, Anthony lead Blazers over ThunderSPORTSMalditas save PH from shutout“We all know that the way we played wasn’t in the level on what we are capable of,” said Pons in Filipino Saturday at Filoil Flying V Centre. “We weren’t at one hundred percent there, coach said that it was just 60 percent.”The 0-6 Lady Warriors, who played their first game without beleaguered former head coach Francis Vicente, managed to steal the third set to prevent a sweep. Pussycat Dolls set for reunion tour after 10-year hiatus Read Next LATEST STORIES FEU posts 2nd straight win at expense of UE Brace for potentially devastating typhoon approaching PH – NDRRMC Don’t miss out on the latest news and information. John Lloyd Cruz a dashing guest at Vhong Navarro’s wedding “We have to explain to each other that we have to give it all especially in our future games,” added Pons as she finished with 21 points.As for Domingo, putting up 19 points and scoring off six blocks was a testament that she’s happy with her current situation with the Lady Tamaraws as they improved to 3-2 in the standings.“It’s quite challenging because I was thinking that I used to play with these girls in front of me, I was with them two years ago,” said Domingo in Filipino. “So what I did is play, do my part, and show that I am happy here in FEU.”Domingo was vital in the clutch for FEU, first denying Mary Ann Mendrez for the Lady Tamaraws’ 23-19 lead in the fourth before scoring an off-balanced kill for her team’s 24-21 match point.ADVERTISEMENT Google honors food scientist, banana ketchup inventor and war hero Maria Orosa MOST READ Families in US enclave in north Mexico hold sad Thanksgiving LOOK: Iya Villania meets ‘Jumanji: The Next Level’ cast in Mexico Typhoon Kammuri accelerates, gains strength en route to PH AFP official booed out of forum View comments Far Eastern University head coach George Pascua said that his players did show a little bit of mercy when they beat University of the East in four sets in the UAAP Season 80 women’s volleyball tournament.ADVERTISEMENT
TÜV SÜD launched its new Internet of Things (cellular testing service. It is the only laboratory in the UK to offer a fully dedicated Narrowband-IoT (NB-IoT) test and certification service, helping manufacturers to gain access to global markets faster. Focused on Industry 4.0 applications, NB-IoT enables a vast number of multiple machines, devices and services to connect at low cost, while optimising battery life. Manufacturers producing such technologies must meet demanding test requirements and are under pressure to keep up with changes to regulatory and country-specific requirements.The new TÜV SÜD service performs regulatory testing against international and country-specific mandatory requirements, delivering manufacturers seamless market entry across multiple countries. TÜV SÜD can also advise if a particular device chipset or network technology will work in the manufacturer’s intended market, as currently technology acceptance is not standardised and differs in each region.Alongside NB-IoT testing, TÜV SÜD also supports cellular applications using the rival protocol, LTE Cat.M, which enables devices to connect directly to a 4G network. Currently the global roll-out of NB-IoT technology is further advanced than that of LTE Cat.M.Share this:TwitterFacebookLinkedInMoreRedditTumblrPinterestWhatsAppSkypePocketTelegram Tags: Tools & Software Continue Reading Previous Lanner: Virtulization-optimized solution with multi-core processorNext Farnell: online reference tool provides detailed information on connectors