359 research outputs found
Chronic pain after lower abdominal surgery: do catechol-O-methyl transferase/opioid receptor μ-1 polymorphisms contribute?
No full textBackground\ud
Preoperative pain, type of operation and anesthesia, severity of acute postoperative pain, and psychosocial factors have been identified as risk factors for chronic postsurgical pain (CPP). Recently, it has been suggested that genetic factors also contribute to CPP. In this study, we aimed to determine whether the catechol-O-methyl transferase (COMT) and opioid receptor μ-1 (OPRM1) common functional polymorphisms rs4680 and rs1799971 were associated with the incidence, intensity, or duration of CPP in patients after lower abdominal surgery.\ud
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Methods\ud
One hundred and two patients with American Society of Anesthesiologists (ASA) physical status I/II underwent either abdominal radical prostatectomy (n = 45) or hysterectomy (n = 57). The incidences of CPP in the pelvic and scar areas were evaluated in all patients three months after surgery.\ud
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Results\ud
Thirty-five (34.3%) patients experienced CPP after lower abdominal surgery. Within this group, six (17.1%) patients demonstrated symptoms of neuropathic pain. For COMT rs4680, 22 (21.6%) patients had Met158Met, 55 (53.9%) patients had Val158Met, and 25 (24.5%) patients had Val158Val. No association was found between CPP phenotypes (incidence, intensity, and duration) and different rs4680 genotypes. For OPRM1 rs1799971, only CPP patients carrying at least one copy of the G allele had higher pain intensity than A118A carriers (p=0.02). No associations with other phenotypes were found. No combined effect of COMT/OPRM1 polymorphisms on CPP phenotypes was observed.\ud
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Conclusions\ud
OPRM1 genotype influences CPP following lower abdominal surgery. COMT didn’t affect CPP, suggesting its potential modality-specific effects on human pain
The Effect of Force Sensor Arrays Integration into Textile for a Novel Head-Foot Wheelchair Steering System
No full textsponsorship: The authors would like to thank dr. ir. Frederick Bossuyt, dr. Frederik Leys, and M.Sc. Paula Veske for the textile lamination on the FSAs that used for Integrations 3 and 4. This research was funded by a C3 grant from the Research Council of the Leuven University, grant number C32/17/056. (Research Council of the Leuven University|C32/17/056)status: Publishe
The use of rental cars in logistics SME-s compared to owned car fleet in the context of economic sustainability
No full textKäesoleva uurimistöö prioriteediks oli uurida, et mis meetodeid peavad transpordi ja logistika VKE-d rakendama enda autopargi suhtes, et vähendada keskkonna jalajälge ja paisata vähem CO2 keskkonda, mis on sätestatud Euroopa Liidu erinevatele keskkonna ja kliimaalaste direktiivide tõttu.
Andmete kogumiseks filtreeris autor ERAA liikmete nimekirjast välja väike ja keskmise suurusega ettevõtted ning seejärel saatis ettevõtetele välja küsimustikud. Küsitluste vastuste põhjal oli võimalik moodustada nö. „keskmine“ ettevõte, mis iseloomustaks hetkel majanduskeskkonnas opereerivaid transpordi ja logistika VKE-sid (0-stsenaarium).
Pärast vastuste saamist otsustas autor võtta küsimustikule vastanud ettevõtete hulgas 10-ettevõtte majandusaasta aruannetest vajalikud arvud, millega arvutada välja suhtarvud ning näidata ära viimase 3 aasta muutuste trend omatud autopargi suhtes.
Edasi töötati välja uued renditeenuste stsenaariumid nii hübriid autopargi omamisele (1-stsenaarium) ja ka täielikult renditud autopargi omamisele (2-stsenaarium), et arvutada välja finantstulemuste erinevused ja suhtarvude muutused.
Rentautode osalise ehk hübriidvormis kasutuselevõtuga (1-stsenaarium) oleks tõusnud ettevõtete suutlikkus teenindada ära oma laenud, eesmärgipärasemalt kasutatud ära oma varasid tegevustulemuste loomisel, iga ettevõtte varasse investeeritud euro oleks toonud kõrgemat kasumit ja üleüldiselt oleks ettevõtte finantsseis paranenud. Rentautode osalise ehk hübriidvormis kasutuselevõtuga (1-stsenaarium) kaasnenud negatiivsed mõjud oleks olnud käibevara mittetõhus kasutamine ja ettevõtja varade finantseerimine suures osas võõrkapitalist.
Täielikult renditud autopargi kasutuselevõtuga (2-stsenaarium) oleks veelgi enam tõusnud ettevõtete suutlikkus teenindada ära oma laenud võrreldes 1- stsenaariumiga, veelgi enam oleks eesmärgipärasemalt kasutatud ära oma varasid võrreldes 1- stsenaariumiga tegevustulemuste loomisel, iga ettevõtte varasse investeeritud euro oleks toonud veelgi kõrgemat kasumit võrreldes 1- stsenaariumiga ja üleüldiselt oleks ettevõtte finantsseis veelgi paranenud võrreldes 1- stsenaariumiga. Täielikult renditud autopargi kasutuselevõtuga (2-stsenaarium) kaasnenud negatiivsed mõjud oleks olnud käibevara mittetõhus edasikasutamise jätkumine ja suurem tõus ning veelgi suurem võõrkapitalist ettevõtja varade finantseerimine.
Uuringust tulenevate järelduste ja kogutud informatsiooni põhjal teeb autor ühe ettepaneku, kuidas transpordi ja logistika VKE-d võiksid rentautod kasutusele võtta. Ettepanek hõlmab hübriidvormis autopargi rakendamist ehk rentautode osalist kasutamist. Rentautode osalise kasutamise rakendamine võimaldab ettevõtetel parandada oma finantstulemusi ja näha positiivseid suhtarvude muutusi, samas hoides transformatsiooniga kaasnevad riskid tasakaalus. Autor soovitab täielikult renditud autoparki vältida, kuna transformatsiooniga kaasnevad riskid ületavad ettevõtte opereerimisest saadavat tulu ehk kasu.
Teravalt päevakorral oleva kliimapoliitika tõttu leiab autor, et hübriidvormis ehk rentautode osaline kasutamine aitab transpordi ja logistika VKE-del parandada majanduslikku kestlikkust ja samas hoida tasakaalus üleminekuga kaasnevad riskid tänapäeva kõrge euribori, Euroopa Liidu poolt sätestatud erinevate keskkonna ja kliimaalaste direktiivide ning täbara majandusolukorra tingimustes. Autor peab oluliseks, et antud teemat tuleks transpordi ja logistika VKE-del täiendavalt uurida, arvestades, et Euroopa Liidu kliimaseaduste kohaselt peavad EL-i riigid aastaks 2030 vähendama heitgaaside koguseid vähemalt 55%, et saavutada kliimaneutraalsus aastaks 2050.This summary provides a comprehensive overview of a research study assessing: The use of rental cars in logistics SME-s compared to owned car fleet in the context of enonomic sustainability. This study is driven by the latest directives established by the European Union and development strategies in the short- and long-term planning horizon. This study aims to research what methods transportation and logistics SME-s have to apply to their fleet in order to reduce the environmental footprint and emit less CO2 into the environment, which is stipulated due to the various environmental and climate directives of the European Union.
The purpose of this thesis is to clarify whether the use of rental cars and rental car service in transportation and logistics SME-s reduces the costs of owning a car fleet, and to investigate whether the economic sustainability of the company is thereby improved.
Research questions include:
1. What is the financial impact of using rental cars?
2. How could rental cars be integrated into the company's operations?
3. What risks are involved in this transitsion?
To collect data, the author filtered out SME-s from the list of ERAA members, and then sent out questionnaires to the companies. Based on the answers to the surveys, it was possible to form so called „average“ company, which would characterize transportation and logistics SME-s currently operating in the economic environment (scenario 0). After receiving the answers, the author decided to take the necessary numbers from the annual reports of 10 companies amongst the companies that answered the questionnaire, with which to calculate the ratios and show the trend of potential changes in the last 3 years in relation to the owned car fleet.
Further, new rental service scenarious for both hybrid (partial introduction of rental cars) fleet ownership (scenario 1) and fully rented fleet ownership (scenario 2) were developed to calculate differences in financial performance and changes in ratios.
The study revealed, that with the partial or hybrid introduction of rental cars (scenario 1), the ability of companies to service their loans would have increased, their assets would have been used more purposefully in creating operational results, each euro invested in the company's assets would have brought a higher profit, and overall the company's financial position would have improved. The negative effects associated with the partial or hybrid introduction of rental cars (scenario 1) would have been the inefficient use of current assets and the financing of the company's assets largely from foreign capital.
With the introduction of a fully rented car fleet (scenario 2), the ability of companies to service their loans would have increased even more compared to scenario 1, their assets would have been used even more purposefully in creating operational results compared to scenario 1, each euro invested in the company's assets would have brought an even higher profit compared to scenario 1, and overall the company's financial position would have improved even more compared to scenario 1. The negative effects associated with the introduction of fully rented car fleet (scenario 2) would have been the continuation and higher increase in the inefficient use of current assets and even greater financing of the company's assets largely from foreign capital.
Based on the conclusions from the research and collected information, the author makes one proposal on how transportation and logistics SME-s could use rental cars. The proposal includes the implementation of a car fleet in hybrid form, i.e. partial use of rental cars. The implementation of partial use of rental cars allows companies to improve their financial results and see positive changes in ratios, while keeping the risks associated with the transformation in balance. The author recommends avoiding a fully rented car fleet, as the risks associated with the transformation exceed the income or benefits, that come from operating the company.
Due to the climate policy that is acutely on the agenda, the author believes, that the hybrid form, i.e. the partial use of rental cars, helps transportation and logistics SME-s to improve their economic sustainability. Whilst improving the economic sustainability of transportation and logistics SME-s, at the same time it helps to balance the risks associated with the transition in the conditions of today's high Euribor, various environmental and climate directives set by the European Union, and the overall poor economic situation. The author considers it important, that this topic should be further investigated by transportation and logistics SME-s, considering that according to the climate laws of the European Union, EU countries must reduce the amount of exhaust gases by at least 55% by 2030 in order to achieve climate neutrality by 2050
Indications préliminaires
No full textTerminologie. — Je désigne la langue vulgaire écrite au moyen âge par le néologisme scripta. L’expression « la scripta » est synonyme de l’allemand « die Schriftsprache ». Je fais précéder du signe ° les formes reprises à la scripta, afin d’indiquer qu’elles n’ont pas nécessairement une valeur phonétique littérale : °marissal, °archidiakenes, °veske. Écriture phonétique. — Les notations phonétiques sont mises entre crochets. Elles ne comportent aucune difficulté. La nature ouverte ou fermée d..
Monitoring Body Fluids in Textiles: Combining Impedance and Thermal Principles in a Printed, Wearable, and Washable Sensor
No full textThis work explores the feasibility of coupling two different techniques, the impedance and the transient plane source (TPS) principle, to quantify the moisture content and its compositional parameters simultaneously. The sensor is realized directly on textiles with the use of printing and coating technology. Impedance measurements use the fluid's electrical properties, while the TPS measurements are based on the thermal effusivity of the liquid. Impedance and TPS measurements show equal competency in measuring the fluid volume with a lowest measurable quantity of 0.5 mu L, enabling ultralow volume passive measurements for sweat analysis. Both sensor principles were tested by monitoring the drying of a wet cloth and the measurements show perfect repeatability and accuracy. Nevertheless, when the biofluid property changes, the TPS sensor does not reflect this information on its readings, whereas, on the other hand, impedance can provide information on compositional changes. However, since the volume of the fluid changes simultaneously, one cannot differentiate between a volume change and a compositional change from impedance measurements alone. Therefore, we show in this work that we can apply impedance to measure the compositional properties; meanwhile, the TPS measurements accurately carry out volume measurements irrespective of the interferences from its compositional variations. To prove this, both of these techniques are applied for the quantification and composition monitoring of sweat, showing the capability to measure moisture content and compositional parameters simultaneously. TPS measurements can also be an indicator of the local temperature of the medium confined by the sensor, and it does not influence the fluid parameters. Compiling both impedance and thermal sensors in a single platform triggers smart wearable prospects of metering the liquid volume and simultaneously analyzing other compositional changes and body temperature. Finally, the repeatability and stability of the sensor readings and the washability of the device are tested. This device could be a potential sensing tool in real-life applications, such as wound monitoring and sweat analysis, and could be a promising addition toward future smart wearable sensors.Deferme, W (corresponding author), Hasselt Univ, Inst Mat Res IMO IMOMEC 1, B-3590 Diepenbeek, Belgium ; IMEC, Div IMOMEC, B-3590 Diepenbeek, Belgium.
[email protected]
Development of the High School Elective Course "Fashion Industry and Styling" to Support the Ethical and Digital Future of the Fashion Industry
No full textLõputöö keskendus keskkooli valikaine „Rõivatööstus ja stilistika“ kursuse arendamisele, et toetada rõivatööstuse eetilist ja digitaalset tulevikku. Töö käigus annab autor põhjaliku ülevaate hariduse rollist noorte tarbimiskäitumise kujundamisel ja vastutustundliku mõtteviisi arendamisel.
Uuringud tõestavad, et keskkoolis rõivatööstuse ja stilistika valikaine pakkumine toetab õpilaste teadlikkust ja avardab nende tulevikuvõimalusi. Õpilased näitasid suurt huvi eetilise moe ja jätkusuutlike lahenduste vastu, sealhulgas tarneahela läbipaistvuse ja tootmise keskkonnamõjude mõistmise vastu. Stilistika valdkonnas väärtustasid noored praktilisi oskusi, mis aitavad neil arendada oma isiklikku stiili ja teha teadlikumaid ostuotsuseid.
Õpilased on avatud valikainetele, mis seovad teooriat praktilise õppimisega, näiteks projektipõhise õppe ja grupitöö kaudu. Sarnaste valikkursuste analüüs ja sihtrühma ootuste uurimine aitasid kujundada kursuse, mis ühendab teooria ja praktilise õppimise ning pakub tõelist tuge õpilaste teadmiste ja oskuste arendamiseks. Näiteks sisaldasid ettepanekud grupiprojekte, praktilisi ülesandeid ja õppekäike tootmisettevõtetesse, mis haakusid hästi uurimiskavaga ja andsid reaalset lisaväärtust õpilaste teadmistele ja kogemustele. Tulemused näitasid, et sellised meetodid suurendasid õpilaste huvi ja valmisolekut teemadega süveneda.
Lõputööst saavad kõige enam kasu keskkooliõpilased, kes omandavad kursuse kaudu olulisi teadmisi rõivatööstuse eetilistest ja tehnoloogilistest aspektidest. Haridusasutused ja õpetajad saavad kasutada uuenduslikke õpetamismeetodeid ja pakkuda teemakäsitlusi, mis vastavad noorte huvidele. Ka kõrgkoolidele on see töö väärtuslik – see aitab paremini valmistada ette tulevasi õppijaid rõivatööstuse ja jätkusuutlikkuse valdkonnas.
Lõputöö koostamine pakkus autorile mitmekülgseid teadmisi ja sügavamat arusaama rõivatööstuse ja hariduse vahelisest seosest. Samuti õpetas see protsess, kui oluline on uurida sihtrühma ootusi ja vajadusi. Ankeetküsitlused ja intervjuud aitasid mõista, mida noored tõeliselt väärtustavad ja millist mõju võib teadlik tarbimine nende tulevikuvalikutele avaldada. Praktiline kokkupuude haridusvaldkonna ja moemaailma spetsialistidega inspireeris autorit mõistma, kuidas teooria ja praktika ühendamine võib muuta õppimise motiveerivamaks ja tähenduslikumaks. Autor tunneb tänulikkust võimaluse eest panustada hariduse ja rõivatööstuse ühendamisesse ning leiab, et see töö on andnud väärtuslikud teadmised ja kogemused edasiseks karjääriks ning enesearenguks.This thesis focused on Development of the High School Elective Course "Fashion Industry and Styling" to Support the Ethical and Digital Future of the Fashion Industry. The author gained valuable insights into how education can play a crucial role in shaping young people's consumption habits and fostering a sense of responsibility.
A study program developed in collaboration with Rakvere State Gymnasium and Tallinn University of Applied Sciences introduces young people to the opportunities in the textile sector, fostering awareness, creativity, and a sense of personal style. The research demonstrates that offering a high school elective on the textile industry and styling significantly enhances students awareness and expands their future opportunities. Students expressed a strong interest in ethical fashion and sustainable solutions, particularly in understanding supply chain transparency and the environmental impact of production. Within the styling domain, students valued practical skills that help them develop a personal sense of style and make more informed purchasing decisions.
Students showed openness to courses that combine theoretical knowledge with hands-on learning, such as project-based activities and group work. The analysis of similar elective courses and the study of student expectations helped shape a curriculum that effectively integrates theory with practical application. Suggestions included group projects, practical assignments, and field trips to production facilities, all of which aligned well with the research objectives and provided real added value to the students’ learning experience. These methods proved to increase student engagement and readiness to explore the topics in depth.
The primary beneficiaries of this thesis are high school students, who will acquire crucial knowledge about the ethical and technological aspects of the textile industry through this course. Additionally, educational institutions and teachers benefit from innovative teaching approaches and relevant subject matter that align with student interests. Higher education institutions can also use these findings to better prepare future learners by enhancing their awareness and skills in sustainable fashion and textile technologies.
The process of creating this thesis provided the author with multifaceted knowledge and a deeper understanding of the intersection between the textile industry and education. It also highlighted the importance of examining the target group’s expectations and needs. Surveys and interviews helped uncover what students truly value and how conscious consumption can influence their future choices. Practical engagement with professionals in both education and the fashion industry inspired the author to see how bridging theory and practice can make learning more engaging and impactful.
The author feels grateful for the opportunity to contribute to the integration of education and the textile industry, acknowledging that this work has provided valuable insights and experiences for future career development and personal growth
Technological Process Improvement of a Technical Textile Product Applied on Thermal Protection Aid
No full textLõputöö tehti ettevõttes Protex Balti AS ja põhineb mudel „MKIV“ tootmise analüüsil, mille alusel sooviti parendada ka kliendi Microsoft Exceli programmis asuvat tabelit selliselt, et see hakkaks varakult märku andma, kui laost hakkab mõni kangas või furnituur otsa saama. Mudel „MKIV“ on ettevõtte uus toode, termokostüüm, mis on mõeldud päästepaadis pääsenute soojendamiseks ning kaitseks vihma eest. Mudelile koostati furnituuride tabel, detailide ja lekaalide loetelu, koostati lõiked ning helkurite märkimiseks lekaal, sest antud tootele ei tohi puurauke teha. Kirjeldati ka kostüümi tootmise tehnoloogiat ning koostati läbilõiked. Töös uuriti ka erinevaid kuumsulatusõmbluste meetodeid ning sobilikke keevitusmasinate mudeleid. Protex Balti AS-il puudub sobiv masin mudeli „MKIV“ keevitamiseks, ning seoses sellega valiti töös välja neli sobivat masinat, millega sobiks toode kokku keevitada. Mudeli tellinud klient pakkus ettevõttele omapoolse masina variandi, mille soetamist ettevõte võiks kaaluda. Lõputöös võrreldakse seda masinat autori poolt valitud seadmetega, ning pakutakse välja nendest masinatest parim variant, milleks osutus ultrahelimeetodil põhinev masin „Nucleus Rotosonic V4E“. Masin valiti välja seetõttu, et lisaks mudeli „MKIV“ ühendamisele on selle seadmega võimalik keevitada veel väga palju erinevate tehnoloogiliste sõlmedega tooteid, sealhulgas ka väga komplitseeritud mudeleid. Sellise masina soetamine tuleks ettevõttele tulevikuperspektiivis kasuks, sest ettevõtte strateegiasse on sisse kirjutatud suurendada tarkade rõivaste tootmist ning tegeleda rohkem tehniliste tekstiilidega. Sellise võimsa ja multifunktsionaalse masina, nagu seda on „Nucleus Rotosonic V4E“, olemasolu annaks Protexile võimaluse vastu võtta selliseid väljakutseid, mida iga teine ettevõte ei saaks ning seeläbi olla tehnilise tekstiili valdkonnas eesrindlik. Ettevõtte esialgne materjalide tabel oli koondatud ühele vahelehele. See sisaldas üle saja erinevat kangast ja furnituuri, 26 mudelit, lao inventuuri ning tootmisgraafikut. Nii suur andmete kogum tegi tabeliga töötamise aeganõudvaks ning ebamugavaks. Tabeli efektiivsuse parendamise eesmärgil loodi Excelisse täiesti uus materjalide tabel, kus olid andmed jagatud viiele erinevale vahelehele. Ettevõtte poolt püstitatud probleemi lahendamise jaoks koostati programmeerimiskeelega VBA kood, mille käivitades värvub tootmisgraafikus tellimuse lahter, kus on kirjas kui palju materjali kulub toodetavate mudelite peale kuus, punaseks, kui laovaru on väiksem, kui antud kuus toodetavatele mudelitele materjali kulub. Teisisõnu, tabel annab ühe nupuvajutusega märku, kui materjali peab juurde tellima. Tänu sellele võimalusele muutus tabel pea 15% efektiivsemaks, mis on umbes üks tund tööpäevast. Seda seetõttu et nüüd ei pea enam informatsiooni kättesaamiseks arutama planeerija ja juurdelõikusega ning füüsiliselt kontrollima kangaste olemasolu. Kergendatud on ka tolli jaoks informatsiooni sisse töötlemine.The purpose of this thesis is to improve Protex Balti AS’s table of materials for it’s customer who ordered the "MKIV" suit so that timely ordering can be made when the warehouse is low on fabrics or auxiliary materials. Further, it recommends the most suitable fabric welding machine for this product. The "MKIV" suit is designed to keep survivors warm and protected against rain, wind and cold in liferafts and lifeboats. This innovative smart wear requires suitable fabric welding machines for its production, which this thesis recommends after discussing the technological process required to make this new product. Given the novel nature of the product, Protex Balti AS does not have a suitable machine for welding the MKIV suit, so four potential machines were considered as options to weld the product—plus a machine offered by the customer who ordered the MKIV suit. This thesis offers a comparative study of the machine proposed by the customer and an alternative equipment options with a recommendation by the author regarding which machine best meets the production needs. The study ultimately concludes that the Nucleus Rotosonic V4E—an ultrasonic fabric welding machine—is the superior choice. This is due to the machine’s virtuosity—not only can it weld the seams necessary for the MKIV suit’s fabric, it can produce a wide range of other complex seams. This includes other water resistant survival wear or even simple raincoats. The acquisition of such a machine would pay dividends far into the future and allow the company to energetically pursue its strategy to increase the production of smart clothing and integrate into products more technical textiles. The addition of a powerful and multifunctional machine like the Nucleus Rotosonic V4E would give Protex Balti AS the opportunity to gain a competitive edge by being able to produce products many other companies do not have the technical capacity to produce and thereby lead the cutting edge in the field of technical textiles. The company's original table of materials was grouped into one spreadsheet. It contained more than one hundred different fabrics and accessories, twenty six models, a warehouse inventory and the production schedule. The size of this data set made working with it a long and arduous process. To improve the efficiency of the table, the data was transferred to a completely new excel table of materials consisting of five new spreadsheets. A VBA code was created to alert the user of low stock. When the code is running, it colors the cells in the production schedule based on estimates of how much material will be spent on the models produced per month—with red indicating that less that a months supply is left. In other words, with one click the user can know exactly what material needs to be ordered. Thanks to this automation, the ordering process has become 15% more efficient—equivalent to approximately one hour of the workday for the worker charged with this task. To obtain information about current inventory it is no longer necessary to discuss with several departments, such as the pattern cutting department or even physically check the current fabric quantity as long as the table is kept up to date. Further, the table fascilitates faster processing of paperwork for customs. Together this translates into potential lower costs, higher profits and a competitve advantage over manufacturers of similar goods
D-Egg: A dual PMT optical module for IceCube
No full textThe D-Egg, an acronym for "Dual optical sensors in an Ellipsoid Glass for Gen2,"is one of the optical modules designed for future extensions of the IceCube experiment at the South Pole. The D-Egg has an elongated-sphere shape to maximize the photon-sensitive effective area while maintaining a narrow diameter to reduce the cost and the time needed for drilling of the deployment holes in the glacial ice for the optical modules at depths up to 2700 m. The D-Egg design is utilized for the IceCube Upgrade, the next stage of the IceCube project also known as IceCube-Gen2 Phase 1, where nearly half of the optical sensors to be deployed are D-Eggs. With two 8-inch high-quantum efficiency photomultiplier tubes (PMTs) per module, D-Eggs offer an increased effective area while retaining the successful design of the IceCube digital optical module (DOM). The convolution of the wavelength-dependent effective area and the Cherenkov emission spectrum provides an effective photodetection sensitivity that is 2.8 times larger than that of IceCube DOMs. The signal of each of the two PMTs is digitized using ultra-low-power 14-bit analog-to-digital converters with a sampling frequency of 240 MSPS, enabling a flexible event triggering, as well as seamless and lossless event recording of single-photon signals to multi-photons exceeding 200 photoelectrons within 10 ns. Mass production of D-Eggs has been completed, with 277 out of the 310 D-Eggs produced to be used in the IceCube Upgrade. In this paper, we report the design of the D-Eggs, as well as the sensitivity and the single to multi-photon detection performance of mass-produced D-Eggs measured in a laboratory using the built-in data acquisition system in each D-Egg optical sensor module
Bayesian multimessenger search method for common sources of gravitational waves and high-energy neutrinos
No full textMultimessenger astrophysics is undergoing a transition towards low-latency searches based on signals that could not individually be established as discoveries. The rapid identification of signals is important in order to initiate timely follow-up observations of transient emission that is only detectable for short time periods. Joint searches for gravitational waves and high-energy neutrinos represent a prime motivation for this strategy. Both gravitational waves and high-energy neutrinos are typically emitted over a short time frame of seconds to minutes during the formation or evolution of compact objects. In addition, detectors searching for both messengers observe the whole sky continuously, making observational information on potential transient sources rapidly available to guide follow-up electromagnetic surveys. The direction of high-energy neutrinos can be reconstructed to subdegree precision, making a joint detection much better localized than a typical gravitational-wave signal. Here we present a search strategy for joint gravitational-wave and high-energy neutrino events that allows the incorporation of astrophysical priors and detector characteristics following a Bayesian approach. We aim to determine whether a multimessenger correlated signal is a real event, a chance coincidence of two background events, or the chance coincidence of an astrophysical signal and a background event. We use an astrophysical prior that is model agnostic and takes into account mostly geometric factors. Our detector characterization in the search is mainly empirical, enabling detailed realistic accounting for the sensitivity of the detector that can depend on the source properties. By this means, we can calculate the false alarm rate for each multimessenger event which is required for initiating electromagnetic follow-up campaigns.</p
The IceCube Pie Chart: Relative Source Contributions to the Cosmic Neutrino Flux
No full textNeutrino events from IceCube have recently been associated with multiple astrophysical sources. Interestingly, these likely detections represent three distinct astrophysical source types: active galactic nuclei (AGNs), blazars, and tidal disruption events (TDEs). Here, we compute the expected contributions of AGNs, blazars, and TDEs to the overall cosmic neutrino flux detected by IceCube based on the associated events, IceCube’s sensitivity, and the source types’ astrophysical properties. We find that, despite being the most commonly identified sources, blazars cannot contribute more than 11% of the total flux (90% credible level), consistent with existing limits from stacked searches. On the other hand, we find that either AGNs or TDEs could contribute more than 50% of the total flux (90% credible level), although stacked searches further limit the TDE contribution to ≲30%. We also find that so-far unknown source types contribute at least 10% of the total cosmic flux with a probability of 80%. We assemble a pie chart that shows the most likely fractional contribution of each source type to IceCube’s total neutrino flux
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