2,166 research outputs found

    TeV-scale Seesaw with Quintuplet Fermions

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    We propose a new seesaw model based on fermionic hypercharge zero weak quintuplet in conjunction with additional scalar quadruplet which attains an induced vev. The model provides both tree-level seesaw ~ v^6/M^5 and a loop-suppressed radiative ~ (1 / 16 \pi^2) v^2/M contributions to active neutrino masses. The empirical masses m_\nu ~ 10^{-1} eV can be achieved with M ~ TeV new states, accessible at the LHC. For 5 fb^{-1} of accumulated integrated luminosity at the LHC, there could be ~ 500 doubly-charged \Sigma^{++} or \bar{\Sigma^{++}} fermions with mass M_\Sigma = 400 GeV, leading to interesting multi-lepton signatures. The neutral component of the fermion quintuplet, previously identified as minimal dark matter candidate, becomes unstable in the proposed seesaw setup. The stability can be restored by introducing a Z_2 symmetry, in which case neutrinos get mass only from radiative contributions.Comment: 19 pages, 9 figures, corresponds to published versio

    Impact of nerve surgery on opioid and medication use in patients with chronic nerve injuries

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    Introduction: Limited information is available regarding the ability of nerve surgery to affect medication use patterns in patients with chronic pain or neuropathy due to nerve injury. Methods: A retrospective survey was distributed to all operative patients (N = 767) from a single nerve surgeon\u27s practice between 2014 and 2020. Data collected included demographics, specifics of the injury and symptoms, medication and opioid use before surgery, and medication/opioid use following surgery. Results: Out of the 767 patients, 209 (27.2%) completed the survey. Average age was 48.8 (SD = 19.1) years; 68.9% female and 31.1% male. More than 50% of the patients took at least three medications. More than 50% of the patients after surgery did not need medication or had significant reduction; 54.1% of the patients took opioid medication daily, and 97.3% of patients reported that narcotic medications did not resolve their problem. Patients rated the effectiveness (Likert scale 0-10) of opioid medications in general at an average 3.25 Ā± 2.03. Of patients who took opioids regularly, 61.6% reported a negative effect of these medications on daily or professional activities. After surgery, more than 50% of the patients did not need opioids or had a significant reduction in opioid usage. Conclusions: Untreated nerve injuries lead to ongoing chronic pain, explaining why medications are mostly ineffective in eliminating symptoms. In this study, nerve surgery targeting the anatomical source of symptoms effectively reduced both opioid and nonopioid medication use

    Procjena fizičkog opterećenja statističkom analizom srčane frekvencije u radnice na vrpci u punionici pića

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    Physical work load was estimated in a female conveyor-belt worker in a bottling plant. Estimation was based on continuous measurement and on calculation of average heart rate values in three-minute and one-hour periods and during the total measuring period. The thermal component of the heart rate was calculated by means of the corrected effective temperature, for the one-hour periods. The average heart rate at rest was also determined. The work component of the heart rate was calculated by subtraction of the resting heart rate and the heart rate measured at 50 W, using a regression equation. The average estimated gross energy expenditure during the work was 9.6Ā±1.3 kJ/min corresponding to the category of light industrial work. The average estimated oxygen uptake was 0.42Ā±0.06 L/min. The average performed mechanical work was 12.2Ā±4.2 W, i.e. the energy expenditure was 8.3Ā±1.5%.U radu je prikazan način procjene fizičkog opterećenja u radnice na vrpci u punionici pića, temeljene na kontinuiranom mjerenju i izračunavanju prosječnih vrijednosti srčane frekvencije u trominutnim i jednosatnim razdobljima, te tijekom čitavog razdoblja mjerenja. Regresijskom jednadžbom koja koristi vrijednost korigirane efektivne temperature, izračunane iz parametara mikroklime mjerenih u jednosatnim razdobljima, izračunata je toplinska sastavnica srčane frekvencije. Tijekom mirovanja također je određena prosječna vrijednost srčane frekvencije. Oduzimanjem srčane frekvencije u mirovanju i toplinske sastavnice srčane frekvencije od aktualne srčane frekvencije, dobivena je radna sastavnica srčane frekvencije za sva spomenuta razdoblja. Iz vrijednosti srčane frekvencije u mirovanju i srčane frekvencije postignute pri opterećenju od 50 W na biciklergometru dobivena je regresijska jednadžba korelacije frekvencije i izvrÅ”enog rada, na temelju koje je izračunavan izvrÅ”eni rad u spomenutim razdobljima. Iz primitka kisika pri opterećenju od 50 W na biciklergometru, primitka kisika na razini bazalnog metabolizma, srčane frekvencije pri opterećenju od 50 W i srčane frekvencije na razini bazalnog metabolizma izračunana je regresijska jednadžba korelacije srčane frekvencije i primitka kisika, i prikazan procijenjeni primitak kisika tijekom rada u svim razdobljima mjerenja. Primitak kisika na razini bazalnog metabolizma izračunan je iz energetske potroÅ”nje dobivene jednadžbom po Harrisu i Benedictu, a primitak kisika pri opterećenju od 50 W iz nomograma koji se koristi pri ergometriji. Iz procijenjenog primitka kisika izračunavana je bruto energetska potroÅ”nja za sva razdoblja mjerenja. Prosječna procijenjena bruto energetska potroÅ”nja tijekom Å”est sati efektivnog rada ispitanice iznosila je 9.7Ā±1.3 kJ/min,Å”to odgovara kategoriji laganog industrijskog rada. Prosječni procijenjeni primitak kisika u istom razdoblju iznosio je 0,45Ā±0,06 L/min, prosječno izvrÅ”eni mehanički rad 12,5Ā±4,2 W, odnosno energetska efikasnost 7,8Ā±1,4%

    The Evolution of Payload Data Capabilities on the Commercial Visiting Vehicles that Service the International Space Station

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    For over 10 years, NASA has been working with U.S.-based commercial companies to support the design, development, and operations of new commercial space vehicles. The purpose of these vehicles is to provide cargo and crew transportation services to the International Space Station (ISS) and to stimulate the commercial space transportation industry to Low-Earth Orbit (LEO). Along with the ability to provide a couple tons of cargo to the ISS each mission, the commercial visiting vehicles also provide the ability to transfer NASA payloads to and from the ISS in an active, powered state. To take advantage of this capability, NASA requirements for the data services that payloads need while they are integrated into the visiting vehicles have grown with each set of commercial contracts. Today, NASA desires for payload data services encompass a variety of capabilities including payload health and status (H&S) telemetry monitoring, visiting vehicle environment data monitoring, and payload commanding. The intent of these capabilities is to provide payload developers with situational awareness and the ability to quickly diagnose any problems with payload operations prior to vehicle docking or post-landing to support immediate troubleshooting response. As new requirements for payload data services have emerged over the years, the ISS Payload Operations Integration Center (POIC) at the NASA Marshall Space Flight Center (MSFC) has established ground segment interfaces to the visiting vehicle control centers to enable payload developers to use these services. Many technical and programmatic challenges have been faced while establishing these interfaces. The most significant challenge faced has been in finding the right balance amongst providing interfaces to payloads that are compatible with the ISS so that payload hardware or software changes are not necessary to ensure compatibility with the visiting vehicles; keeping POIC ground system development costs low by standardizing implementation approaches across commercial vehicle partners; and fostering commercialization through supporting vendor-unique implementations that are commercially economical. This paper will first detail the data services that will be available to payload users under each commercial visiting vehicle contract. Secondly, this paper will offer discussion of the most significant technical and programmatic challenges faced to-date in offering these new data services to payload developers

    The Evolution of Payload Data Capabilities on the Commercial Visiting Vehicles that Service the International Space Station

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    In 2008, NASA awarded the first contracts to U.S. commercial companies to deliver cargo and supplies to the International Space Station (ISS). These contracts, called the first phase of Commercial Resupply Services (CRS1), were awarded to Space Exploration Technologies (SpaceX) and Orbital Sciences. Under the CRS1 contracts, commercial visiting vehicles not only provide a couple tons of cargo to the ISS each mission, but they also provide the ability for payloads to be transferred to the ISS in an active, powered state. Prior to the start of the CRS1 program, most vehicles that serviced the ISS transported science experiments as passive cargo. Therefore, the CRS1 program through offering frequent flight opportunities with powered payload transport capability ushered in a new era in which NASA and payload developers could reimagine operational concepts for payloads during the transit phase to and from the ISS. To take advantage of this powered payload transport capability, NASA first added requirements under the CRS1 program for the commercial vehicles to provide telemetry monitoring services for pressurized payloads to give payload developers situational awareness during the transport phase. Since then, payload developer use-cases for visiting vehicle data services during free-flight have evolved with each new commercial visiting vehicle contract to cover a variety of payload monitoring and control abilities. Additional commercial contracts include the Commercial Crew Transportation Capability (CCtCap) contracts that were awarded to SpaceX and Boeing, and the second phase of Commercial Resupply Services (CRS2) contracts that were awarded to SpaceX, Orbital ATK (formerly Orbital Sciences), and Sierra Nevada Corporation. Commercial crew flights will commence in 2018, and the first flight under the CRS2 program is currently planned for 2019

    Hidrografska svojstva sjevernog Jadrana od listopada 2002. do rujna 2003. godine, u razdoblju s anomalno toplim ljetom

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    CTD data were collected during 38 cruises in the northeastern Adriatic from October 2002 to September 2003 and were analyzed in the context of long-term variability (from data collected over a period of 38 years). A prognostic statistical model was created to fit the long-term data and predicted values were compared to those of the in situ CTD measurements. As with air temperatures, values attained by the sea in summer 2003 far exceeded those expected by predictive models and were induced by very large heat input from the atmosphere. In conditions of very low regional freshwater input and intrusions of more saline water masses from the south, salinity values in the spring/summer period lay far outside typical salinity values for the area.Analizirani su podaci o temperaturi, salinitetu i gustoći skupljani na 38 krstarenja u sjeveroistočnom Jadranu od listopada 2002. do rujna 2003. godine i uspoređeni s prognoziranim vrijednostima iz statističkog modela. Model je načinjen na temelju podataka sakupljanih u ovom području u tridesetosmogodiÅ”njem razdoblju. PovrÅ”inske su temperature mora ljeti 2003. godine bile daleko iznad očekivanih, Å”to je bila posljedica pojačanih povrÅ”inskih protoka topline iz atmosfere u more. U proljeće i ljeto 2003. godine vrijednosti saliniteta bile su također značajno iznad prosjeka, zbog niskih dotoka slatke vode i intruzije slane vode iz srednjeg Jadrana
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