Rotating Instability (RI) is a typical unsteady flow phenomenon in compressors and may cause severe aerodynamic noise and even potential nonsynchronous vibration. Most studies of RI are based on the uniform inflow, ig...Rotating Instability (RI) is a typical unsteady flow phenomenon in compressors and may cause severe aerodynamic noise and even potential nonsynchronous vibration. Most studies of RI are based on the uniform inflow, ignoring the influence of inlet distortions. This study investigates the mechanism of RI in a transonic rotor through full-annulus unsteady simulations, with a particular focus on the effects of boundary layer ingesting distortions. The results show that at the uniform inflow, the RI fluctuations with the broadband hump can be observed over a relatively wide mass flow rate range, and its origin can be attributed to the coupling effect between the tip leakage flow and shear layer instability. At the inlet distortions, the broadband hump only occurs with partial circumferential locations. This kind of flow phenomenon is defined as Partial Rotating Instability (PRI). The PRI only occurs in a narrower mass flow rate range in which the circumferential range of strong shear is sufficiently large and the self-induced unsteady effects are strong enough. Further, this study confirms that the averaged tip leakage flow axial momentum at the onset of RI or PRI is close, so it can be used as the parameter to determine whether RI or PRI occurs.展开更多
Effect of UV-B radiation on ingesting and nutritional selecting behavior of the roifer Brachionus urceus on 5 species of microlgae were studied under controlled laboratory conditions. Restdts showed that enhanced UV-B...Effect of UV-B radiation on ingesting and nutritional selecting behavior of the roifer Brachionus urceus on 5 species of microlgae were studied under controlled laboratory conditions. Restdts showed that enhanced UV-B radiation significantly inhibited ingesting of the rotifer B. urceus when it was fed with 5 species of micro-algae （p〈0.05）. The ingesting selectivity rate varied with the UV-B radiation enhancement when it was fed with 5 species micro-algal mixture. Results indicated that the enhanced UV-B radiation could affect ingesting and nutritional selectivity of B. urceus.展开更多
Boundary layer ingesting(BLI)fans are required to operate under distorted inflow conditions,which significantly reduces their efficiency[1,2].Accurately predicting fan losses is crucial for designing high-performance,...Boundary layer ingesting(BLI)fans are required to operate under distorted inflow conditions,which significantly reduces their efficiency[1,2].Accurately predicting fan losses is crucial for designing high-performance,distortion-tolerant fans.展开更多
Caustic ingestion is a relatively rare but potentially catastrophic gastroentero-logical emergency.Upper gastrointestinal(GI)endoscopy is currently regarded as the gold standard modality not only to assess the depth a...Caustic ingestion is a relatively rare but potentially catastrophic gastroentero-logical emergency.Upper gastrointestinal(GI)endoscopy is currently regarded as the gold standard modality not only to assess the depth and the extension of GI caustic injury,but also to guide the appropriate treatment.Intriguingly,contrast-enhanced computed tomography(CECT)has recently emerged as a promising non-invasive and more accurate alternative to endoscopy in this setting.However,to date,evidence concerning the role of CECT as an alternative or complementary diagnostic tool to endoscopy in caustic ingestion is still limited.The aim of our review was to summarize and discuss the current evidence concerning the role of CECT in the emergency diagnosis of caustic ingestion and its value in assessing injury severity among non-pediatric patients.展开更多
BACKGROUND Venlafaxine,a serotonin-norepinephrine reuptake inhibitor,is widely prescribed for the treatment of major depressive disorder.At therapeutic dose,it is generally safe,with a low incidence of adverse effects...BACKGROUND Venlafaxine,a serotonin-norepinephrine reuptake inhibitor,is widely prescribed for the treatment of major depressive disorder.At therapeutic dose,it is generally safe,with a low incidence of adverse effects.However,massive venlafaxine inge-stion can cause serious cardiotoxicity,leading to life-threatening arrhythmias.CASE SUMMARY A 31-year-old woman with a history of depression ingested 14.8 g of venlafaxine along with 6 mg of estazolam and 6 mg of flunitrazepam.On admission,2 hours post-ingestion,she presented only with mild QTc prolongation.At 4 hours post-ingestion,she developed a generalized tonic-clonic seizure.Following endo-tracheal intubation,intravenous midazolam infusion was initiated and 50 g of activated charcoal was administered via a nasogastric tube.At 15 hours post-ingestion,she developed ventricular tachycardia that rapidly progressed to refr-actory ventricular fibrillation,which was successfully treated with veno-arterial extracorporeal membrane oxygenation.Toxicological analysis revealed serum ve-nlafaxine and O-desmethylvenlafaxine concentrations 17µg/mL and 10µg/mL,respectively,at 15 hours post-ingestion.CONCLUSION In cases of massive venlafaxine ingestion,continuous intensive monitoring,particularly of QTc,is essential for at least 24 hours,even when initial clinical signs are mild.If refractory ventricular arrhythmias occur,prompt ini-tiation of veno-arterial extracorporeal membrane oxygenation should be considered.展开更多
BACKGROUND Sharp foreign body ingestion can cause gastrointestinal tract mucosa injury and requires proper endoscopic removal.Typically,protective devices are used to reduce mucosal damage.This case presents an altern...BACKGROUND Sharp foreign body ingestion can cause gastrointestinal tract mucosa injury and requires proper endoscopic removal.Typically,protective devices are used to reduce mucosal damage.This case presents an alternative approach for the endoscopic removal of a large,irregular,and sharp foreign body(chicken bone)when traditional protective devices are inadequate,thus contributing to the management of such ingestions.CASE SUMMARY A 57-year-old male presented with a history of swallowing an irregular and sharp-pointed chicken bone.Emergent endoscopy showed it was tightly embedded in the esophageal wall,with minor bleeding.The chicken bone was grasped and moved cautiously using a foreign forceps.It was loosened after repeated attempts but could not pass through the pharynx.Considering possible mucosal damage,it was carefully pushed into the stomach cavity and then wrapped in a condom.The chicken bone was retrieved uneventfully by grasping the open edge of the condom with foreign forceps.No additional damage was found,except for primary esophageal injuries caused by the embedded chicken bone.The patient was discharged on the following day.Our experience demonstrated that condoms can be an alternative as a protective device under such conditions.CONCLUSION Condoms can serve as an alternative when traditional protective devices are unsuitable.Because of its smooth and oily nature,it can provide mucosal protection and lubrication during endoscopic removal.展开更多
BACKGROUND Cases of esophageal,airway,and pericardial perforations caused by chicken bone ingestion are rare worldwide,but their incidence has shown an upward trend in recent years.Injuries caused by chicken bones are...BACKGROUND Cases of esophageal,airway,and pericardial perforations caused by chicken bone ingestion are rare worldwide,but their incidence has shown an upward trend in recent years.Injuries caused by chicken bones are often more severe,leading to infections and,in extreme cases,perforation of the common carotid artery,pericardium,trachea,or even the heart,posing life-threatening risks.CASE SUMMARY We present a case of a patient who sustained combined esophageal and pericardial injuries with subsequent pericardial effusion due to chicken bone ingestion.The clinical manifestations included chest pain and widespread ST-segment elevation on electrocardiography.CONCLUSION The patient’s symptoms and signs were not entirely consistent with myocardial infarction.Chest computed tomography played a crucial role in clarifying the etiology and provided critical evidence for devising an effective treatment strategy.展开更多
BACKGROUND Bezoars usually compile human fibers and debris.A special form of bezoar in case of psychologically altered individuals is the trichobezoar.It consists of voluntarily swallowed hair bulks and is normally re...BACKGROUND Bezoars usually compile human fibers and debris.A special form of bezoar in case of psychologically altered individuals is the trichobezoar.It consists of voluntarily swallowed hair bulks and is normally removed via gastroscopy.Trichobezoars leading to ileus have rarely been reported.CASE SUMMARY A 24-year-old female patient presented to the emergency room with abdominal pain,nausea,and vomiting for 3 d.Her previous medical and psychiatric history was unremarkable.Laboratory analysis showed iron deficiency anemia,leukocytosis,and elevated liver enzymes.An abdominal CT scan revealed a dense structure in the patients’stomach which turned out to be a huge trichobezoar completely obstructing the pylorus.The trichobezoar had to be removed surgi-cally.During her postoperative course,a subcutaneous seroma formed.After a single puncture,the rest of the recovery process was unremarkable,and the patient recovered fully.CONCLUSION A mechanical bowel obstruction is a potentially life-threatening event for every patient.In our case a young female was suffering from severe symptoms of an obstruction which might have resulted in serious harm without successful surgical management.展开更多
In modern aero-engine,the turbine rim seals whose purpose is to reduce the ingress are located in a complex flow region between the mainstream and secondary air flows.The sealing air discharged from the compressor of ...In modern aero-engine,the turbine rim seals whose purpose is to reduce the ingress are located in a complex flow region between the mainstream and secondary air flows.The sealing air discharged from the compressor of engine is used to purge turbine cavity.In order to examine the effects of ingress through four distinct rim seals,a one-stage test rig was used in the experiments presented in this work.At a Reynolds number of 5.16×10^(5) in the mainstream and(0.85-2.13)×10^(6) in the rotational,the radial pressure distribution on the stator was determined.To assess flow characteristics and sealing efficacy,measurements of the swirl ratio and CO_(2) concentration were made.The reliability of turbine rim-seals is determined by the locations of the hook and teeth,as well as their effect on hot gas ingestion.To evaluate the performance of four types of seals:a datum double-rim seal and three derivatives with different clearances,the data are employed.Due to the inlet air position,the swirl ratio exhibited a pronounced inflection for all the rim seals.The sealing efficiency can be decreased by putting the hook closer to the rim or by taking the teeth out.Static pressure measurements in the turbine cavity indicate that the seal position has a significant impact.The analysis results revealed that the existence of slot vortex is beneficial to improving efficiency.展开更多
Rationale:Acute caustic ingestion from suicidal intent is not usual in emergency departments in developed countries.One of the substances commonly ingested by suicidal patients,phosphoric acid,tends to cause multi-sys...Rationale:Acute caustic ingestion from suicidal intent is not usual in emergency departments in developed countries.One of the substances commonly ingested by suicidal patients,phosphoric acid,tends to cause multi-system derangements.Patient’s Concern:A 41-year-old male patient presented with complaints of throat discomfort,severe generalized abdominal pain,and multiple episodes of hematemesis after ingesting a restroom cleaning solution.Diagnosis:Poisoning by acute caustic ingestion(containing<30%phosphoric acid and<4%ethylene glycol).Interventions:The patient was administered 50 mL of 8.4%sodium bicarbonate solution followed by an isotonic sodium bicarbonate solution running at 500 mL/h,a hyperkalemia kit,ceftriaxone,metronidazole,omeprazole,and atropine.The patient then underwent urgent hemodialysis.Outcomes:The patient suffered gastrointestinal bleeding as a result of local caustic injury.In addition,his course of illness was complicated by severe acidemia from high anion gap metabolic acidosis and deranged electrolytes(hyperphosphatemia,hyperkalemia,and hypocalcemia).He developed multi-organ failure and eventually demised.Lessons:The clinician needs to be mindful of the multi-system complications arising from such a caustic ingestion.These patients need to be monitored closely for deterioration,and have prompt management of the various arising complications,to reduce the high morbidity and mortality associated with this condition.展开更多
Objective: Few studies have evaluated the effect of oral sodium hyaluronate (SH) ingestion on the moisture content of the superficial stratum corneum. This study aimed to assess whether oral SH ingestion improves the ...Objective: Few studies have evaluated the effect of oral sodium hyaluronate (SH) ingestion on the moisture content of the superficial stratum corneum. This study aimed to assess whether oral SH ingestion improves the moisture content of the upper layer of the stratum corneum, which is susceptible to changes in environmental humidity, using the Skicon 200EX. Design: Randomized, double-blind, placebo-controlled, parallel-group study. Participants: One hundred healthy Japanese men and women aged 20 - 64 years. Interventions: Oral ingestion of one 119-mg SH or dextrin (placebo) capsule once daily for 8 weeks. Evaluations: Measurement of water content in the superficial stratum corneum of the face and upper extremities using the Skicon 200EX. Results: Overall facial stratum corneum water content changes were significantly higher at 8 weeks in the SH group compared to the placebo group. Conclusions: In healthy Japanese adults, oral SH ingestion improved skin moisture by increasing the stratum corneum water content. Clinical Trial Registration: The study protocol was preregistered with the Clinical Trials Registry System (registration no. UMIN000053322, January 11, 2024).展开更多
Gluconacetobacter hansenii GK-1 is an acid-resistant gram-negative bacterium used in vinegar brewing. Oral ingestion of GK-1 was previously reported to help maintain immunity and reduce nasal discomfort. Considering t...Gluconacetobacter hansenii GK-1 is an acid-resistant gram-negative bacterium used in vinegar brewing. Oral ingestion of GK-1 was previously reported to help maintain immunity and reduce nasal discomfort. Considering the suggested mechanism of action of activation of regulatory T cells via TLR4 to control Th1/Th2 balancing, GK-1 is also assumed to reduce skin discomfort secondary to immune reactions;however, this has not been validated in humans. Thus, we conducted a randomized, double-blind, placebo-controlled, parallel-group study on 100 healthy Japanese men and women (mean age, 47.6 ± 1.01 years) aged 20–64 years who consumed GK-1 (9 × 109 cells) daily for 8 weeks. Visual analog scale for overall, facial, arm, and leg skin discomfort was assessed before and after ingestion. The cumulative days of skin discomfort during the ingestion period were assessed. Compared with the placebo group, the G. hansenii GK-1 group had a significantly lower visual analog scale for overall and facial skin discomfort after 8 weeks and cumulative days of skin discomfort. Moreover, there were no adverse events attributable to G. hansenii GK-1. This study confirmed that oral ingestion of G. hansenii GK-1 contributed to skin integrity. The study protocol was preregistered at the Clinical Trials Registry System (registration no. UMIN000053005, December 7, 2023).展开更多
Background: Social media platforms are popular among children and often feature challenges that become viral. Notably, the Tide Pod® and Benadryl® challenges encouraged viewers to ingest these substances for...Background: Social media platforms are popular among children and often feature challenges that become viral. Notably, the Tide Pod® and Benadryl® challenges encouraged viewers to ingest these substances for their visual appeal and hallucinogenic effects, respectively. This study aimed to assess the clinical impact and outcomes of single-use detergent sacs (SUDS) and diphenhydramine challenges on pediatric ingestions reported to United States (U.S.) Poison Control Centers (PCCs). Methods: We conducted a retrospective review of pediatric exposures reported to U.S. PCCs using data from the National Poison Data System (NPDS). The study included intentional single-substance ingestions of both brand-name and generic forms of SUDS and diphenhydramine among children ≤ 19 years. We compared the number of calls, clinical effects, disposition, and management strategies for SUDS (pre: 01/01/17 to 12/31/17 vs. post: 01/01/18 to 12/31/18) and diphenhydramine (pre: 08/01/19 to 07/31/20 vs. post: 08/01/20 to 07/31/21) ingestions 12 months before and after the introduction of the respective social media challenges. Differences in proportions were compared using the Chi-square test. Results: During the study period, 469 ingestions of SUDS and 5,702 ingestions of diphenhydramine were reported. Post-challenge periods saw an increase in both SUDS (pre: 82 vs. post: 387;372% increase) and diphenhydramine ingestions (pre: 2,672 vs. post: 3,030;13% increase). While there were no significant changes in moderate or major clinical outcomes, hospitalizations increased post-challenge for both SUDS [pre: 4 (4.9%) vs. post: 33 (8.5%);p = 0.25] and diphenhydramine [pre: n = 904 (33.8%) vs. post: 1,190 (39.3%);p Conclusion: Pediatric ingestions reported to U.S. PCCs and hospitalizations increased coinciding with the introduction of Tide Pod® and Benadryl® challenges. While causality cannot be definitively established, it is essential for pediatricians and parents to be aware of these challenges and educate vulnerable children about the harmful effects of participation in such challenges.展开更多
Objectives The purpose was to directly assess in-competition thermoregulatory responses in recreational runners during a city marathon conducted in cool,ambient conditions using a two-pill ingestion strategy.Methods T...Objectives The purpose was to directly assess in-competition thermoregulatory responses in recreational runners during a city marathon conducted in cool,ambient conditions using a two-pill ingestion strategy.Methods Thirty-two recreational runners(age:38.7±10.2 years,mass:73.9±11.0 kg,height:177±8 cm)were invited to participate in this study.Core temperature was continuously assessed using telemetric ingestible pills.Each runner swallowed two pills:the first pill(Pill 1)11 h:47 min±1 h:01 min pre-race(before overnight sleep)and the second(Pill 2)2 h:35 min±0 h:54 min pre-race(on wakening).Results Pre-race core temperature for Pill 1 was significantly different from Pill 2,with values of 37.4±0.4℃and 37.1±0.6℃,respectively(p=0.006).The mean core temperature during the race was higher for Pill 1 compared to Pill 2(38.5±0.5℃and 37.8±1.0℃,respectively;p<0.001).Peak core temperature was higher for Pill 1 compared to Pill 2(39.1±0.5℃and 38.8±0.5℃,respectively;p=0.03).Post-race core temperature was higher for Pill 1 compared to Pill 2(38.8±0.7℃and 38.1±1.3℃,respectively;p=0.02).Conclusions The timing of pill ingestion significantly impacted core temperature and hence timing of pill ingestion should be standardised(5 h:30 min–7 h prior to measurement).Despite the relatively cool ambient conditions during the race,a significant number of runners achieved a high core body temperature(≥39℃),which was not accompanied by any signs of heat illness.展开更多
Prevention has a paramount role in reducing the incidence of corrosive ingestion especially in children, yet this goal is far from being reached in developing countries, where such injuries are largely unreported and ...Prevention has a paramount role in reducing the incidence of corrosive ingestion especially in children, yet this goal is far from being reached in developing countries, where such injuries are largely unreported and their true prevalence simply cannot be extrapolated from random articles or personal experience. The specific pathophysiologic mechanisms are becoming better understood and may have a role in the future management and prevention of long-term consequences, such as esophageal strictures. Whereas the mainstay of diagnosis is considered upper gastrointestinal endoscopy, computed tomography and ultrasound are gaining a more significant role, especially in addressing the need for emergency surgery, whose morbidity and mortality remains high even in the best hands. The need to perform emergency surgery has a persistent long-term negative impact both on survival and functional outcome. Medical or endoscopic prevention of stricture is debatable, yet esophageal stents, absorbable or not, show promising data. Dilatation is the first therapeutic option for strictures and bougies should be considered especially for long, multiple and tortuous narrowing. It is crucial to avoid malnutrition, especially in developingcountries where management strategies are influenced by malnutrition and poor clinical conditions. Late reconstructive surgery, mainly using colon transposition, offers the best results in referral centers, either in children or adults, but such a difficult surgical procedure is often unavailable in developing countries. Possible late development of esophageal cancer, though probably overemphasized, entails careful and long-term endoscopic screening.展开更多
AIM:To study a retrospective analysis of patients who presented to the emergency departments(ED)with complaints related to foreign body ingestions.METHODS:Patients older than 16 years of age who presented to the ED be...AIM:To study a retrospective analysis of patients who presented to the emergency departments(ED)with complaints related to foreign body ingestions.METHODS:Patients older than 16 years of age who presented to the ED between January 1stand December 31stof 2010 with complaints related to swallowed foreign bodies were identified from electronic health records and patient charts.RESULTS:A total of 100 patients presented with a complaint of foreign body ingestion during the study period.Overall,an X-ray was performed on 75 patients,and a fiberoptic evaluation was performed on45 patients.A foreign body was detected in 46(46%)patients.The diagnostic yield of the X-ray was 27(36%)out of 75 patients,while the diagnostic yield of the fiberoptic evaluations was 21(47%)out of 45 patients.The detected foreign bodies were mostly located in the esophagus(17 out of 46 foreign bodies detected).When the types of ingested foreign bodies were evaluated,52(52%)patients reported ingesting food,and19(19%)patients reported swallowing pins.An X-ray was performed on 33 patients with accidental food ingestions but yielded a positive result in only two cases.In 12 out of 21 patients with accidental food ingestion who underwent fiberoptic evaluation,the foreign material was detected and removed.CONCLUSION:Plain radiography is helpful in the localization of radiopaque swollen foreign bodies,while fiberoptic methods are useful as both diagnostic and therapeutic tools,regardless of radiopacity.展开更多
The intentional ingestion of foreign objects(IIFO) is described more commonly in prison populations than in the general population, with an estimated annual incidence of 1 in 1900 inmates in our state correctional fac...The intentional ingestion of foreign objects(IIFO) is described more commonly in prison populations than in the general population, with an estimated annual incidence of 1 in 1900 inmates in our state correctional facilities. Incidents often involve ingestion of small metal objects(e.g., paperclips, razor blades) or other commonly available items like pens or eating utensils. Despite ingestion of relatively sharp objects, most episodes can be clinically managed with either observation or endoscopy. Surgery should be reserved for those with signs or symptoms of gastrointestinal perforation or obstruction. For those with a history of IIFO, efforts should focus on prevention of recurrenceas subsequent episodes are associated with higher morbidity, significant healthcare and security costs. The pattern of IIFO is often repetitive, with escalation both in frequency of ingestions and in number of items ingested. Little is known about successful prevention strategies, but efforts to monitor patients and provide psychiatric care are potential best-practice strategies. This article aims to provide state-of-the art review on the topic, followed by a set of basic recommendations.展开更多
A streamwise-body-force-model （SBFM） is developed and applied in the overall flow simulation for the distributed propulsion system, combining internal and external flow fields. In view of axial stage effects, fan or...A streamwise-body-force-model （SBFM） is developed and applied in the overall flow simulation for the distributed propulsion system, combining internal and external flow fields. In view of axial stage effects, fan or compressor effects could be simplified as body forces along the streamline. These body forces which are functions of local parameters could be added as source terms in Navier-Stokes equations to replace solid boundary conditions of blades and hubs. The val- idation of SBFM with uniform inlet and distortion inlet of compressors shows that pressure performance characteristics agree well with experimental data. A three-dimensional simulation of the integration configuration, via a blended wing body aircraft with a distributed propulsion system using the SBFM, has been completed. Lift coefficient and drag coefficient agree well with wind tunnel test results. Results show that to reach the goal of rapid integrated simulation combining internal and external flow fields, the computational fluid dynamics method based on SBFM is reasonable.展开更多
AIM:To evaluate the Z-line visualization by the PillCamTM SB2 using three different ingestion protocols. METHODS:Ninety consecutive patients undergoing small bowel capsule endoscopy(SBCE)between January and May 2008 w...AIM:To evaluate the Z-line visualization by the PillCamTM SB2 using three different ingestion protocols. METHODS:Ninety consecutive patients undergoing small bowel capsule endoscopy(SBCE)between January and May 2008 were included in the study. They swallowed the capsule in the standing(Group A= 30),supine(Group B=30)and right supine positions (Group C=30).Baseline patient characteristics, difficulties in capsule ingestion,esophageal transit times(ETT)and Z-line visualization were noted. RESULTS:No significant differences were found between the groups with regard to baseline patient characteristics,ingestion difficulties and complete SB examinations(P>0.05).At least 1 frame of the Z-line was detected in 15.8%,46.7%and 90%of patients in groups A,B and C,respectively(P<0.001).The average number of Z-line images was 0.21±0.53,3.23 ±6.59 and 5.53±7.55 and the mean%of the Z-linedetected was 71.3,25.1 and 8.3,in groups A,B and C, respectively(both P<0.001).ETT times were longer in the supine group followed by the right supine and the standing groups(median of 237 s vs 64 s and 39 s, respectively;P<0.001). CONCLUSION:Z-line visualization in patients undergoing SBCE can be accurately achieved in most cases when the capsule is swallowed in the right supine position.展开更多
In this paper, the effect of different amount of protrusion on various parameters in rotor–stator system was experimentally studied by measuring CO_2 concentration and pressure, in order to obtain the optimal protrus...In this paper, the effect of different amount of protrusion on various parameters in rotor–stator system was experimentally studied by measuring CO_2 concentration and pressure, in order to obtain the optimal protrusion amount.The parameters of different dimensionless sealing flow were measured under the condition that the annulus Reynolds number was 4.39 × 10~5 and the rotating Reynolds number was 1.05 × 10~6.The results show that the change of the amount of protrusions has little effect on the static pressure in the cavity, and the static pressure change near the sealing ring is almost negligible.But the total pressure and sealing efficiency increase first and then decrease with the increase of the amount of protrusion.The variation of power consumption is the same.A complex vortex structure will appear at the high radius region when the protrusion is installed.On the other hand, the protrusion can effectively reduce the minimum sealing flow of the rotor–stator cavity.Furthermore, considering the sealing efficiency and power consumption,the best range of the protrusion amount is about 36.The ratio near this range can optimally balance the alleviation of the gas ingestion and the reduction of the power consumption.展开更多
基金supports of the National Natural Science Foundation of China(Nos.52076129,92360308,52376027)the Shanghai Municipal Education Commission of China(No.2023-02-4)+1 种基金the Fundamental Research Funds for the Central Universities of Chinathe United Innovation Center(UIC)of Aerothermal Technologies for Turbomachinery of China.
文摘Rotating Instability (RI) is a typical unsteady flow phenomenon in compressors and may cause severe aerodynamic noise and even potential nonsynchronous vibration. Most studies of RI are based on the uniform inflow, ignoring the influence of inlet distortions. This study investigates the mechanism of RI in a transonic rotor through full-annulus unsteady simulations, with a particular focus on the effects of boundary layer ingesting distortions. The results show that at the uniform inflow, the RI fluctuations with the broadband hump can be observed over a relatively wide mass flow rate range, and its origin can be attributed to the coupling effect between the tip leakage flow and shear layer instability. At the inlet distortions, the broadband hump only occurs with partial circumferential locations. This kind of flow phenomenon is defined as Partial Rotating Instability (PRI). The PRI only occurs in a narrower mass flow rate range in which the circumferential range of strong shear is sufficiently large and the self-induced unsteady effects are strong enough. Further, this study confirms that the averaged tip leakage flow axial momentum at the onset of RI or PRI is close, so it can be used as the parameter to determine whether RI or PRI occurs.
基金Supported by the National Natural Science Foundation of China (30270258, 40506028)the National High Technology Research and Development Program of China (2002AA648010)+1 种基金the Encouraging Foundation for Outstanding Youth Scientists of Shandong Province (03BS120)China Postdoctoral Sience Foundation(2005037237)
文摘Effect of UV-B radiation on ingesting and nutritional selecting behavior of the roifer Brachionus urceus on 5 species of microlgae were studied under controlled laboratory conditions. Restdts showed that enhanced UV-B radiation significantly inhibited ingesting of the rotifer B. urceus when it was fed with 5 species of micro-algae （p〈0.05）. The ingesting selectivity rate varied with the UV-B radiation enhancement when it was fed with 5 species micro-algal mixture. Results indicated that the enhanced UV-B radiation could affect ingesting and nutritional selectivity of B. urceus.
基金supported by the National Key Research and Development Program(Grant No.2022YFF0708903)the Ningbo Key Technology Re-search and Development Program(Grant No.2023Z018)+3 种基金the National Natural Science Foundation of China(Grant No.52275043)the Youth Fund of National Natural Science Foundation of China(Grant Nos.72301015,52105046)the Young Elite Scientist Sponsorship Program by China Association for Science and Technology(Grant Nos.2022QNRC001,YESS20220292)the Liupanshan Laboratory Basic Research Program(Grant No.LPS-2024-KY-D-JC-0009)。
文摘Boundary layer ingesting(BLI)fans are required to operate under distorted inflow conditions,which significantly reduces their efficiency[1,2].Accurately predicting fan losses is crucial for designing high-performance,distortion-tolerant fans.
文摘Caustic ingestion is a relatively rare but potentially catastrophic gastroentero-logical emergency.Upper gastrointestinal(GI)endoscopy is currently regarded as the gold standard modality not only to assess the depth and the extension of GI caustic injury,but also to guide the appropriate treatment.Intriguingly,contrast-enhanced computed tomography(CECT)has recently emerged as a promising non-invasive and more accurate alternative to endoscopy in this setting.However,to date,evidence concerning the role of CECT as an alternative or complementary diagnostic tool to endoscopy in caustic ingestion is still limited.The aim of our review was to summarize and discuss the current evidence concerning the role of CECT in the emergency diagnosis of caustic ingestion and its value in assessing injury severity among non-pediatric patients.
文摘BACKGROUND Venlafaxine,a serotonin-norepinephrine reuptake inhibitor,is widely prescribed for the treatment of major depressive disorder.At therapeutic dose,it is generally safe,with a low incidence of adverse effects.However,massive venlafaxine inge-stion can cause serious cardiotoxicity,leading to life-threatening arrhythmias.CASE SUMMARY A 31-year-old woman with a history of depression ingested 14.8 g of venlafaxine along with 6 mg of estazolam and 6 mg of flunitrazepam.On admission,2 hours post-ingestion,she presented only with mild QTc prolongation.At 4 hours post-ingestion,she developed a generalized tonic-clonic seizure.Following endo-tracheal intubation,intravenous midazolam infusion was initiated and 50 g of activated charcoal was administered via a nasogastric tube.At 15 hours post-ingestion,she developed ventricular tachycardia that rapidly progressed to refr-actory ventricular fibrillation,which was successfully treated with veno-arterial extracorporeal membrane oxygenation.Toxicological analysis revealed serum ve-nlafaxine and O-desmethylvenlafaxine concentrations 17µg/mL and 10µg/mL,respectively,at 15 hours post-ingestion.CONCLUSION In cases of massive venlafaxine ingestion,continuous intensive monitoring,particularly of QTc,is essential for at least 24 hours,even when initial clinical signs are mild.If refractory ventricular arrhythmias occur,prompt ini-tiation of veno-arterial extracorporeal membrane oxygenation should be considered.
文摘BACKGROUND Sharp foreign body ingestion can cause gastrointestinal tract mucosa injury and requires proper endoscopic removal.Typically,protective devices are used to reduce mucosal damage.This case presents an alternative approach for the endoscopic removal of a large,irregular,and sharp foreign body(chicken bone)when traditional protective devices are inadequate,thus contributing to the management of such ingestions.CASE SUMMARY A 57-year-old male presented with a history of swallowing an irregular and sharp-pointed chicken bone.Emergent endoscopy showed it was tightly embedded in the esophageal wall,with minor bleeding.The chicken bone was grasped and moved cautiously using a foreign forceps.It was loosened after repeated attempts but could not pass through the pharynx.Considering possible mucosal damage,it was carefully pushed into the stomach cavity and then wrapped in a condom.The chicken bone was retrieved uneventfully by grasping the open edge of the condom with foreign forceps.No additional damage was found,except for primary esophageal injuries caused by the embedded chicken bone.The patient was discharged on the following day.Our experience demonstrated that condoms can be an alternative as a protective device under such conditions.CONCLUSION Condoms can serve as an alternative when traditional protective devices are unsuitable.Because of its smooth and oily nature,it can provide mucosal protection and lubrication during endoscopic removal.
文摘BACKGROUND Cases of esophageal,airway,and pericardial perforations caused by chicken bone ingestion are rare worldwide,but their incidence has shown an upward trend in recent years.Injuries caused by chicken bones are often more severe,leading to infections and,in extreme cases,perforation of the common carotid artery,pericardium,trachea,or even the heart,posing life-threatening risks.CASE SUMMARY We present a case of a patient who sustained combined esophageal and pericardial injuries with subsequent pericardial effusion due to chicken bone ingestion.The clinical manifestations included chest pain and widespread ST-segment elevation on electrocardiography.CONCLUSION The patient’s symptoms and signs were not entirely consistent with myocardial infarction.Chest computed tomography played a crucial role in clarifying the etiology and provided critical evidence for devising an effective treatment strategy.
文摘BACKGROUND Bezoars usually compile human fibers and debris.A special form of bezoar in case of psychologically altered individuals is the trichobezoar.It consists of voluntarily swallowed hair bulks and is normally removed via gastroscopy.Trichobezoars leading to ileus have rarely been reported.CASE SUMMARY A 24-year-old female patient presented to the emergency room with abdominal pain,nausea,and vomiting for 3 d.Her previous medical and psychiatric history was unremarkable.Laboratory analysis showed iron deficiency anemia,leukocytosis,and elevated liver enzymes.An abdominal CT scan revealed a dense structure in the patients’stomach which turned out to be a huge trichobezoar completely obstructing the pylorus.The trichobezoar had to be removed surgi-cally.During her postoperative course,a subcutaneous seroma formed.After a single puncture,the rest of the recovery process was unremarkable,and the patient recovered fully.CONCLUSION A mechanical bowel obstruction is a potentially life-threatening event for every patient.In our case a young female was suffering from severe symptoms of an obstruction which might have resulted in serious harm without successful surgical management.
基金the financial support of the Science Center for Gas Turbine Project,China(No.P2022-A-Ⅱ-007-001).
文摘In modern aero-engine,the turbine rim seals whose purpose is to reduce the ingress are located in a complex flow region between the mainstream and secondary air flows.The sealing air discharged from the compressor of engine is used to purge turbine cavity.In order to examine the effects of ingress through four distinct rim seals,a one-stage test rig was used in the experiments presented in this work.At a Reynolds number of 5.16×10^(5) in the mainstream and(0.85-2.13)×10^(6) in the rotational,the radial pressure distribution on the stator was determined.To assess flow characteristics and sealing efficacy,measurements of the swirl ratio and CO_(2) concentration were made.The reliability of turbine rim-seals is determined by the locations of the hook and teeth,as well as their effect on hot gas ingestion.To evaluate the performance of four types of seals:a datum double-rim seal and three derivatives with different clearances,the data are employed.Due to the inlet air position,the swirl ratio exhibited a pronounced inflection for all the rim seals.The sealing efficiency can be decreased by putting the hook closer to the rim or by taking the teeth out.Static pressure measurements in the turbine cavity indicate that the seal position has a significant impact.The analysis results revealed that the existence of slot vortex is beneficial to improving efficiency.
文摘Rationale:Acute caustic ingestion from suicidal intent is not usual in emergency departments in developed countries.One of the substances commonly ingested by suicidal patients,phosphoric acid,tends to cause multi-system derangements.Patient’s Concern:A 41-year-old male patient presented with complaints of throat discomfort,severe generalized abdominal pain,and multiple episodes of hematemesis after ingesting a restroom cleaning solution.Diagnosis:Poisoning by acute caustic ingestion(containing<30%phosphoric acid and<4%ethylene glycol).Interventions:The patient was administered 50 mL of 8.4%sodium bicarbonate solution followed by an isotonic sodium bicarbonate solution running at 500 mL/h,a hyperkalemia kit,ceftriaxone,metronidazole,omeprazole,and atropine.The patient then underwent urgent hemodialysis.Outcomes:The patient suffered gastrointestinal bleeding as a result of local caustic injury.In addition,his course of illness was complicated by severe acidemia from high anion gap metabolic acidosis and deranged electrolytes(hyperphosphatemia,hyperkalemia,and hypocalcemia).He developed multi-organ failure and eventually demised.Lessons:The clinician needs to be mindful of the multi-system complications arising from such a caustic ingestion.These patients need to be monitored closely for deterioration,and have prompt management of the various arising complications,to reduce the high morbidity and mortality associated with this condition.
文摘Objective: Few studies have evaluated the effect of oral sodium hyaluronate (SH) ingestion on the moisture content of the superficial stratum corneum. This study aimed to assess whether oral SH ingestion improves the moisture content of the upper layer of the stratum corneum, which is susceptible to changes in environmental humidity, using the Skicon 200EX. Design: Randomized, double-blind, placebo-controlled, parallel-group study. Participants: One hundred healthy Japanese men and women aged 20 - 64 years. Interventions: Oral ingestion of one 119-mg SH or dextrin (placebo) capsule once daily for 8 weeks. Evaluations: Measurement of water content in the superficial stratum corneum of the face and upper extremities using the Skicon 200EX. Results: Overall facial stratum corneum water content changes were significantly higher at 8 weeks in the SH group compared to the placebo group. Conclusions: In healthy Japanese adults, oral SH ingestion improved skin moisture by increasing the stratum corneum water content. Clinical Trial Registration: The study protocol was preregistered with the Clinical Trials Registry System (registration no. UMIN000053322, January 11, 2024).
文摘Gluconacetobacter hansenii GK-1 is an acid-resistant gram-negative bacterium used in vinegar brewing. Oral ingestion of GK-1 was previously reported to help maintain immunity and reduce nasal discomfort. Considering the suggested mechanism of action of activation of regulatory T cells via TLR4 to control Th1/Th2 balancing, GK-1 is also assumed to reduce skin discomfort secondary to immune reactions;however, this has not been validated in humans. Thus, we conducted a randomized, double-blind, placebo-controlled, parallel-group study on 100 healthy Japanese men and women (mean age, 47.6 ± 1.01 years) aged 20–64 years who consumed GK-1 (9 × 109 cells) daily for 8 weeks. Visual analog scale for overall, facial, arm, and leg skin discomfort was assessed before and after ingestion. The cumulative days of skin discomfort during the ingestion period were assessed. Compared with the placebo group, the G. hansenii GK-1 group had a significantly lower visual analog scale for overall and facial skin discomfort after 8 weeks and cumulative days of skin discomfort. Moreover, there were no adverse events attributable to G. hansenii GK-1. This study confirmed that oral ingestion of G. hansenii GK-1 contributed to skin integrity. The study protocol was preregistered at the Clinical Trials Registry System (registration no. UMIN000053005, December 7, 2023).
文摘Background: Social media platforms are popular among children and often feature challenges that become viral. Notably, the Tide Pod® and Benadryl® challenges encouraged viewers to ingest these substances for their visual appeal and hallucinogenic effects, respectively. This study aimed to assess the clinical impact and outcomes of single-use detergent sacs (SUDS) and diphenhydramine challenges on pediatric ingestions reported to United States (U.S.) Poison Control Centers (PCCs). Methods: We conducted a retrospective review of pediatric exposures reported to U.S. PCCs using data from the National Poison Data System (NPDS). The study included intentional single-substance ingestions of both brand-name and generic forms of SUDS and diphenhydramine among children ≤ 19 years. We compared the number of calls, clinical effects, disposition, and management strategies for SUDS (pre: 01/01/17 to 12/31/17 vs. post: 01/01/18 to 12/31/18) and diphenhydramine (pre: 08/01/19 to 07/31/20 vs. post: 08/01/20 to 07/31/21) ingestions 12 months before and after the introduction of the respective social media challenges. Differences in proportions were compared using the Chi-square test. Results: During the study period, 469 ingestions of SUDS and 5,702 ingestions of diphenhydramine were reported. Post-challenge periods saw an increase in both SUDS (pre: 82 vs. post: 387;372% increase) and diphenhydramine ingestions (pre: 2,672 vs. post: 3,030;13% increase). While there were no significant changes in moderate or major clinical outcomes, hospitalizations increased post-challenge for both SUDS [pre: 4 (4.9%) vs. post: 33 (8.5%);p = 0.25] and diphenhydramine [pre: n = 904 (33.8%) vs. post: 1,190 (39.3%);p Conclusion: Pediatric ingestions reported to U.S. PCCs and hospitalizations increased coinciding with the introduction of Tide Pod® and Benadryl® challenges. While causality cannot be definitively established, it is essential for pediatricians and parents to be aware of these challenges and educate vulnerable children about the harmful effects of participation in such challenges.
文摘Objectives The purpose was to directly assess in-competition thermoregulatory responses in recreational runners during a city marathon conducted in cool,ambient conditions using a two-pill ingestion strategy.Methods Thirty-two recreational runners(age:38.7±10.2 years,mass:73.9±11.0 kg,height:177±8 cm)were invited to participate in this study.Core temperature was continuously assessed using telemetric ingestible pills.Each runner swallowed two pills:the first pill(Pill 1)11 h:47 min±1 h:01 min pre-race(before overnight sleep)and the second(Pill 2)2 h:35 min±0 h:54 min pre-race(on wakening).Results Pre-race core temperature for Pill 1 was significantly different from Pill 2,with values of 37.4±0.4℃and 37.1±0.6℃,respectively(p=0.006).The mean core temperature during the race was higher for Pill 1 compared to Pill 2(38.5±0.5℃and 37.8±1.0℃,respectively;p<0.001).Peak core temperature was higher for Pill 1 compared to Pill 2(39.1±0.5℃and 38.8±0.5℃,respectively;p=0.03).Post-race core temperature was higher for Pill 1 compared to Pill 2(38.8±0.7℃and 38.1±1.3℃,respectively;p=0.02).Conclusions The timing of pill ingestion significantly impacted core temperature and hence timing of pill ingestion should be standardised(5 h:30 min–7 h prior to measurement).Despite the relatively cool ambient conditions during the race,a significant number of runners achieved a high core body temperature(≥39℃),which was not accompanied by any signs of heat illness.
文摘Prevention has a paramount role in reducing the incidence of corrosive ingestion especially in children, yet this goal is far from being reached in developing countries, where such injuries are largely unreported and their true prevalence simply cannot be extrapolated from random articles or personal experience. The specific pathophysiologic mechanisms are becoming better understood and may have a role in the future management and prevention of long-term consequences, such as esophageal strictures. Whereas the mainstay of diagnosis is considered upper gastrointestinal endoscopy, computed tomography and ultrasound are gaining a more significant role, especially in addressing the need for emergency surgery, whose morbidity and mortality remains high even in the best hands. The need to perform emergency surgery has a persistent long-term negative impact both on survival and functional outcome. Medical or endoscopic prevention of stricture is debatable, yet esophageal stents, absorbable or not, show promising data. Dilatation is the first therapeutic option for strictures and bougies should be considered especially for long, multiple and tortuous narrowing. It is crucial to avoid malnutrition, especially in developingcountries where management strategies are influenced by malnutrition and poor clinical conditions. Late reconstructive surgery, mainly using colon transposition, offers the best results in referral centers, either in children or adults, but such a difficult surgical procedure is often unavailable in developing countries. Possible late development of esophageal cancer, though probably overemphasized, entails careful and long-term endoscopic screening.
文摘AIM:To study a retrospective analysis of patients who presented to the emergency departments(ED)with complaints related to foreign body ingestions.METHODS:Patients older than 16 years of age who presented to the ED between January 1stand December 31stof 2010 with complaints related to swallowed foreign bodies were identified from electronic health records and patient charts.RESULTS:A total of 100 patients presented with a complaint of foreign body ingestion during the study period.Overall,an X-ray was performed on 75 patients,and a fiberoptic evaluation was performed on45 patients.A foreign body was detected in 46(46%)patients.The diagnostic yield of the X-ray was 27(36%)out of 75 patients,while the diagnostic yield of the fiberoptic evaluations was 21(47%)out of 45 patients.The detected foreign bodies were mostly located in the esophagus(17 out of 46 foreign bodies detected).When the types of ingested foreign bodies were evaluated,52(52%)patients reported ingesting food,and19(19%)patients reported swallowing pins.An X-ray was performed on 33 patients with accidental food ingestions but yielded a positive result in only two cases.In 12 out of 21 patients with accidental food ingestion who underwent fiberoptic evaluation,the foreign material was detected and removed.CONCLUSION:Plain radiography is helpful in the localization of radiopaque swollen foreign bodies,while fiberoptic methods are useful as both diagnostic and therapeutic tools,regardless of radiopacity.
文摘The intentional ingestion of foreign objects(IIFO) is described more commonly in prison populations than in the general population, with an estimated annual incidence of 1 in 1900 inmates in our state correctional facilities. Incidents often involve ingestion of small metal objects(e.g., paperclips, razor blades) or other commonly available items like pens or eating utensils. Despite ingestion of relatively sharp objects, most episodes can be clinically managed with either observation or endoscopy. Surgery should be reserved for those with signs or symptoms of gastrointestinal perforation or obstruction. For those with a history of IIFO, efforts should focus on prevention of recurrenceas subsequent episodes are associated with higher morbidity, significant healthcare and security costs. The pattern of IIFO is often repetitive, with escalation both in frequency of ingestions and in number of items ingested. Little is known about successful prevention strategies, but efforts to monitor patients and provide psychiatric care are potential best-practice strategies. This article aims to provide state-of-the art review on the topic, followed by a set of basic recommendations.
基金supported by the National Natural Science Foundation of China (No.51176005)
文摘A streamwise-body-force-model （SBFM） is developed and applied in the overall flow simulation for the distributed propulsion system, combining internal and external flow fields. In view of axial stage effects, fan or compressor effects could be simplified as body forces along the streamline. These body forces which are functions of local parameters could be added as source terms in Navier-Stokes equations to replace solid boundary conditions of blades and hubs. The val- idation of SBFM with uniform inlet and distortion inlet of compressors shows that pressure performance characteristics agree well with experimental data. A three-dimensional simulation of the integration configuration, via a blended wing body aircraft with a distributed propulsion system using the SBFM, has been completed. Lift coefficient and drag coefficient agree well with wind tunnel test results. Results show that to reach the goal of rapid integrated simulation combining internal and external flow fields, the computational fluid dynamics method based on SBFM is reasonable.
文摘AIM:To evaluate the Z-line visualization by the PillCamTM SB2 using three different ingestion protocols. METHODS:Ninety consecutive patients undergoing small bowel capsule endoscopy(SBCE)between January and May 2008 were included in the study. They swallowed the capsule in the standing(Group A= 30),supine(Group B=30)and right supine positions (Group C=30).Baseline patient characteristics, difficulties in capsule ingestion,esophageal transit times(ETT)and Z-line visualization were noted. RESULTS:No significant differences were found between the groups with regard to baseline patient characteristics,ingestion difficulties and complete SB examinations(P>0.05).At least 1 frame of the Z-line was detected in 15.8%,46.7%and 90%of patients in groups A,B and C,respectively(P<0.001).The average number of Z-line images was 0.21±0.53,3.23 ±6.59 and 5.53±7.55 and the mean%of the Z-linedetected was 71.3,25.1 and 8.3,in groups A,B and C, respectively(both P<0.001).ETT times were longer in the supine group followed by the right supine and the standing groups(median of 237 s vs 64 s and 39 s, respectively;P<0.001). CONCLUSION:Z-line visualization in patients undergoing SBCE can be accurately achieved in most cases when the capsule is swallowed in the right supine position.
文摘In this paper, the effect of different amount of protrusion on various parameters in rotor–stator system was experimentally studied by measuring CO_2 concentration and pressure, in order to obtain the optimal protrusion amount.The parameters of different dimensionless sealing flow were measured under the condition that the annulus Reynolds number was 4.39 × 10~5 and the rotating Reynolds number was 1.05 × 10~6.The results show that the change of the amount of protrusions has little effect on the static pressure in the cavity, and the static pressure change near the sealing ring is almost negligible.But the total pressure and sealing efficiency increase first and then decrease with the increase of the amount of protrusion.The variation of power consumption is the same.A complex vortex structure will appear at the high radius region when the protrusion is installed.On the other hand, the protrusion can effectively reduce the minimum sealing flow of the rotor–stator cavity.Furthermore, considering the sealing efficiency and power consumption,the best range of the protrusion amount is about 36.The ratio near this range can optimally balance the alleviation of the gas ingestion and the reduction of the power consumption.
