PERFORMANCE COMPARISON OF DIRECT CONTACT - PACKED BED AND INDIRECT CONTACT - MEMBRANE DEHUMIDIFIERS

This study addresses the challenges a dissolving-grade pulp mill in Canada faced in 2014 in meeting its total reduced sulfur (TRS) gas emission limit. These emissions from the recovery boiler exit are controlled by passing the boiler exit gas through a TRS scrubber system. The mill employs a cyclonic direct contact evaporator to concentrate black liquor to firing solids content. The off-gases from the direct contact evaporator flow to the effluent gas control system that consists of a venturi scrubber, a packed bed scrubber, and a heat recovery unit. Emissions of TRS greater than the regulated limit of 15 ppm were observed for a 4-month period in 2014. The level of emissions measured during this period was significantly higher than about 12 ppm, the expected average value based on historic experience. The problem persisted from mid-June 2014 until the annual mill shutdown in October 2014. The main TRS components detected and the performance of the Teller scrubber in capturing them are examined. Other potential causes for these emissions are identified, including mechanical problems such as broken packing in the TRS packed bed scrubber, broken baffle plates in the scrubber, and cyclone evaporator leaks causing air ingress. Repairs were carried out during the mill shutdown, which eliminated the TRS emissions problem.

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Reduce odor and NH3 emission: condensation of the carbonatation vapors

Sugar Industry ◽

10.36961/si18736 ◽

2017 ◽

pp. 534-537

Author(s):

Nico Antens ◽

Jan L.M. Struijs

Keyword(s):

Direct Contact ◽

Waste Heat ◽

Pilot Scale ◽

Sugar Production ◽

Two Stage ◽

Indirect Contact ◽

Nh3 Emission ◽

Emission Limits ◽

Plant Trials ◽

Contact Condensation

At beet sugar production, vapors from first and second carbonatation contain a significant amount of odor components, NH3 and waste heat, which are normally directly released into the environment. Due to sustainability motivations, obligations regarding odor nuisance and expected stricter regulations regarding NH3 emission limits, Suiker Unie decided to take measures to reduce emission via the carbonatation vapors. During the 2015 beet campaign, pilot scale plant trials have been performed to investigate the effectiveness of indirect contact and direct contact condensation of these vapors. Based on this experimental work a two-stage gas scrubbing concept was designed: in the first stage main goal is condensing the vapors and reuse the heat of condensation to heat up limed juice, while the actual scrubbing takes place in the second scrubber. This two-stage gas scrubbing installation has been built at the Vierverlaten factory and was started up in the 2016 beet campaign. The background, pilot scale trials, concept of design and achieved reductions in odor and NH3 emission at industrial scale are discussed.

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Modeling Ebola Virus Transmission Using Ferrets

mSphere ◽

10.1128/msphere.00309-18 ◽

2018 ◽

Vol 3 (5) ◽

Cited By ~ 6

Author(s):

Marc-Antoine de La Vega ◽

Geoff Soule ◽

Kaylie N. Tran ◽

Kevin Tierney ◽

Shihua He ◽

...

Keyword(s):

Animal Model ◽

Direct Contact ◽

Ebola Virus ◽

Infected Animal ◽

Severe Disease ◽

Virus Transmission ◽

Metal Mesh ◽

Indirect Contact ◽

Specific Antibodies ◽

Bodily Fluids

ABSTRACT Ebola virus (EBOV) has been responsible for sporadic outbreaks in Central Africa since 1976 and has the potential of causing social disruption and public panic as illustrated by the 2013–2016 epidemic in West Africa. Transmission of EBOV has been described to occur via contact with infected bodily fluids, supported by data indicating that infectious EBOV could be cultured from blood, semen, saliva, urine, and breast milk. Parameters influencing transmission of EBOV are, however, largely undefined in part due to the lack of an established animal model to study mechanisms of pathogen spread. Here, we investigated EBOV transmissibility in male and female ferrets. After intranasal challenge, an infected animal was placed in direct contact with a naive ferret and in contact with another naive ferret (separated from the infected animal by a metal mesh) that served as the indirect-contact animal. All challenged animals, male direct contacts, and one male indirect contact developed disease and died. The remaining animals were not viremic and remained asymptomatic but developed EBOV-glycoprotein IgM and/or IgG specific antibodies—indicative of virus transmission. EBOV transmission via indirect contact was frequently observed in this model but resulted in less-severe disease compared to direct contact. Interestingly, these observations are consistent with the detection of specific antibodies in humans living in areas of EBOV endemicity. IMPORTANCE Our knowledge regarding transmission of EBOV between individuals is vague and is mostly limited to spreading via direct contact with infectious bodily fluids. Studying transmission parameters such as dose and route of infection is nearly impossible in naturally acquired cases—hence the requirement for a laboratory animal model. Here, we show as a proof of concept that ferrets can be used to study EBOV transmission. We also show that transmission in the absence of direct contact is frequent, as all animals with indirect contact with the infected ferrets had detectable antibodies to the virus, and one succumbed to infection. Our report provides a new small-animal model for studying EBOV transmission that does not require adaptation of the virus, providing insight into virus transmission among humans during epidemics.

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Direct contact packed bed thermal gradient attenuators: Theoretical analysis and experimental observations

Review of Scientific Instruments ◽

10.1063/1.1564279 ◽

2003 ◽

Vol 74 (5) ◽

pp. 2886-2893 ◽

Cited By ~ 2

Author(s):

Kevin M. Lawton ◽

Steven R. Patterson ◽

Russell G. Keanini

Keyword(s):

Theoretical Analysis ◽

Thermal Gradient ◽

Direct Contact ◽

Packed Bed

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Lucretius and the Salty Taste of Sea Air

Classica et Mediaevalia ◽

10.7146/classicaetmediaevalia.v69i0.124703 ◽

2021 ◽

Vol 69 ◽

pp. 173-217

Author(s):

Pamela Zinn

Keyword(s):

Direct Contact ◽

Water Cycle ◽

Traditional View ◽

Sensory Threshold ◽

De Rerum Natura ◽

Indirect Contact ◽

Salty Taste

This article treats the sense of taste in Epicurean thought through the evidence in Lucretius’ De rerum natura. It reconstructs Lucretius’ account of what taste is and how it works, with a view to explaining instances like the taste of salt by the seaside, where we seem to taste at a distance. I argue that such instances are not exceptions, but examples that reveal more about the processes behind them. When analyzed in conjunction with the physiology of taste and the water cycle, the salty taste of sea air confirms the traditional view that the perception of flavor consistently occurs through direct contact with the object of perception, not through indirect contact with an intermediary. Moreover, it advances the understanding of what comes into contact, what the perceiver contributes to taste, and taste’s sensory threshold.

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Mechanisms of acute ankle syndesmosis ligament injuries in professional male rugby union players: a systematic visual video analysis

British Journal of Sports Medicine ◽

10.1136/bjsports-2020-102281 ◽

2020 ◽

pp. bjsports-2020-102281

Author(s):

Eamonn Delahunt ◽

Garreth Farrell ◽

Andrew Boylan ◽

Fearghal Kerin ◽

Peter Tierney ◽

...

Keyword(s):

Video Analysis ◽

Direct Contact ◽

External Rotation ◽

Rugby Union ◽

Qualitative Description ◽

Ligament Injuries ◽

Injured Limb ◽

Indirect Contact ◽

Injury Mechanisms ◽

Hip Flexion

BackgroundThe mechanisms of acute ankle syndesmosis ligament injuries in professional rugby union are not well understood.AimTo describe the mechanisms of acute ankle syndesmosis ligament injuries in male professional rugby union players using systematic visual video analysis.MethodsAll time-loss acute ankle syndesmosis ligament injuries identified via retrospective analysis of the Leinster Rugby injury surveillance database across the 2013/2014 to 2017/2018 seasons were considered as potentially eligible for inclusion. Three Chartered Physiotherapists (analysts) independently assessed all videos with a final consensus meeting convened to describe the injury mechanisms. One of the analysts developed a qualitative description of each injury mechanism.ResultsThirteen acute ankle syndesmosis injuries were included in this study. The most common biomechanical presentation of the injured limb was characterised by hip flexion, knee flexion, knee valgus, ankle dorsiflexion, pronation and external rotation of the foot. Six of the included injuries (46%) were the result of an external load application to the injured limb (ie, direct contact injuries). In the other seven instances (54%), the injury was the result of a collapse of the injured player’s body mass over the injured ankle joint, while tackling or being tackled, without direct contact to the injured limb (ie, indirect contact injuries).ConclusionInjuries incurred while tackling were exclusively the result of suboptimal tackle mechanics. A majority of injuries incurred while being tackled involved a posterior tackle, which often resulted in a posterior collapse of the injured player’s centre of mass over a fixed externally rotated foot.

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Systematic video analysis of ACL injuries in professional male football (soccer): injury mechanisms, situational patterns and biomechanics study on 134 consecutive cases

British Journal of Sports Medicine ◽

10.1136/bjsports-2019-101247 ◽

2020 ◽

Vol 54 (23) ◽

pp. 1423-1432 ◽

Cited By ~ 3

Author(s):

Francesco Della Villa ◽

Matthew Buckthorpe ◽

Alberto Grassi ◽

Alberto Nabiuzzi ◽

Filippo Tosarelli ◽

...

Keyword(s):

Video Analysis ◽

Direct Contact ◽

Acl Injury ◽

Injury Pattern ◽

Biomechanical Analysis ◽

Knee Valgus ◽

Mechanical Perturbation ◽

Indirect Contact ◽

Acl Injuries ◽

Injury Mechanisms

BackgroundA few small studies have reported on the mechanisms of ACL injury in professional male football.AimTo describe the mechanisms, situational patterns and biomechanics (kinematics) of ACL injuries in professional male football matches.MethodsWe identified 148 consecutive ACL injuries across 10 seasons of professional Italian football. 134 (90%) injury videos were analysed for mechanism and situational pattern, while biomechanical analysis was possible in 107 cases. Three independent reviewers evaluated each video. ACL injury epidemiology (month), timing within the match and pitch location at the time of injury were also reported.Results59 (44%) injuries were non-contact, 59 (44%) were indirect contact and 16 (12%) were direct contact. Players were frequently perturbed immediately prior to injury. We identified four main situational patterns for players who suffered a non-contact or an indirect contact injury: (1) pressing and tackling (n=55); (2) tackled (n=24); (3) regaining balance after kicking (n=19); and (4) landing from a jump (n=8). Knee valgus loading (n=83, 81%) was the dominant injury pattern across all four of these situational patterns (86%, 86%, 67% and 50%, respectively). 62% of the injuries occurred in the first half of the matches (p<0.01). Injuries peaked at the beginning of the season (September–October) and were also higher at the end of the season (March–May).Conclusions88% of ACL injuries occurred without direct knee contact, but indirect contact injuries were as frequent as non-contact injuries, underlying the importance of mechanical perturbation. The most common situational patterns were pressing, being tackled and kicking.

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Contact — but not foul play — dominates injury mechanisms in men’s professional handball: a video match analysis of 580 injuries

British Journal of Sports Medicine ◽

10.1136/bjsports-2018-100250 ◽

2020 ◽

Vol 54 (16) ◽

pp. 984-990 ◽

Cited By ~ 4

Author(s):

Patrick Luig ◽

Werner Krutsch ◽

Thomas Henke ◽

Christian Klein ◽

Hendrik Bloch ◽

...

Keyword(s):

Direct Contact ◽

Knee Injuries ◽

Central Zone ◽

Ankle Injuries ◽

Common Mechanism ◽

Match Analysis ◽

Severe Injuries ◽

Indirect Contact ◽

Injury Mechanisms ◽

Video Material

AimWe aimed to identify patterns and mechanisms of injury situations in men’s professional handball by means of video match analysis.MethodsModerate and severe injuries (absence of >7 days) sustained in competition in one of six seasons (2010 to 2013 and 2014 to 2017) in men’s professional handball were prospectively analysed with a newly developed standardised observation form. Season 2013 to 2014 was excluded because of missing video material.Results580 injuries were identified: 298 (51.4%) contact injuries, 151 (26.0%) indirect contact injuries and 131 (22.6%) non-contact injuries. Head (87.5%), hand (83.8%), shoulder (70.2%) and ankle (62.9%) injuries were mainly sustained during direct contact. Typical contact injuries included collision with an opponent’s upper extremity or torso, and ankle injuries mainly consisted of foot-to-foot collisions. A large proportion (41.7%) of knee injuries were caused by indirect contact, whereas thigh injuries mainly occurred (56.4%) through non-contact mechanism. Wing (56.9%) and pivot (58.4%) players had the highest proportion of contact injuries, whereas backcourt players had a high proportion of indirect contact injuries (31.5%) and goalkeepers of non-contact injuries (48.9%). The injury proportion of foul play was 28.4%. Most injuries occurred in the central zone between the 6-metre and 9-metre lines (26.1%) and during the last 10 min of each match half (OR 1.71, p=0.016).ConclusionsIn men’s professional handball in a league setting, contact — but not foul play — was the most common mechanism associated with moderate and severe injuries. Head, hand, shoulder and ankle injury were mainly sustained during direct contact.

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Effect of direct and indirect contact with mental illness on dangerousness and social distance

International Journal of Social Psychiatry ◽

10.1177/0020764017748181 ◽

2017 ◽

Vol 64 (2) ◽

pp. 112-119 ◽

Cited By ~ 4

Author(s):

Minhwa Lee ◽

Mikyung Seo

Keyword(s):

Mental Illness ◽

Standard Deviation ◽

Interaction Effect ◽

Social Distance ◽

Direct Contact ◽

Indirect Contact ◽

Independent Variables ◽

Main Effect ◽

Dependent Variables ◽

Two Independent Variables

Background: This study is based on the contact hypothesis that contact with mental illness is the most effective anti-stigma strategy. Aims: This study aims to analyze which form of contact can most effectively decrease the dangerousness and social distance associated with schizophrenia, depression and alcoholism. Method: In total, 573 Korean adults ( Mage = 43.71 years, standard deviation ( SD) = 13.41; 54.1% male, 45.9% female) were surveyed about randomly assigned vignettes of schizophrenia, depression and alcoholism. The participants were questioned on the dangerousness and social distance associated with the assigned vignette, as well as direct and indirect contact experience with the mental illness. Two-way analysis of variance (ANOVA) was used to determine the main effect and interaction effect that the type of mental illness and contact experience have on the two dependent variables (dangerousness and social distance). Results: The findings show that the type of mental illness has a significant main effect on dangerousness and social distance, but contact type only has a significant main effect on social distance. Moreover, the two independent variables (mental illness subtype and contact experience) have an interaction effect on two dependent variables (dangerousness and social distance). Therefore, the anti-stigma effect of contact varies according to the type of mental illness. Conclusion: Our findings suggest that appropriate anti-stigma strategies are required for each type of mental illness. Considering that opportunities for direct contact with persons with mental illness are highly limited, it is necessary to actively utilize indirect contact.

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