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1.
Can Vet J ; 61(5): 499-504, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32355348

RESUMO

The hypothesis that neutered dogs in the Veterinary Medical Database (VMDB) are at increased risk for developing hemangiosarcoma (HSA) was tested. Dogs (n = 5736) were diagnosed with HSA from a population of 2 106 324 dogs in the VMDB from 1964 to 2003. A case-control design matched on age and time period was created for general, cardiac, and splenic HSAs. A logistic regression analysis was performed including breed. Spayed females had an odds ratio (OR) of 1.59 for splenic, 1.47 for cardiac, and 1.72 for HSA in general. Castrated males had an OR of 1.26 for splenic and 1.14 for HSA in general compared to intact males. Controlled for historical time period and patient age, VMDB data support that neutering is associated with development of splenic HSA and HSA in general in both male and female dogs, but not cardiac HSA with an apparently lower than previously described magnitude of association. Key clinical message: This case-control design confirms an association between neutering and development of HSA and splenic HSA, but not cardiac HSA, in both male and female dogs. By controlling for time period at diagnosis, the bias of recent early neuter practices is eliminated, suggesting early neuter is not a principal driver of this effect.


La stérilisation est associée avec le développement d'hémangiosarcome chez les chiens dans le Veterinary Medical Database : une étude cas-témoin jumelant l'âge et la période de temps (1964­2003). L'hypothèse dans le Veterinary Medical Database (VNDB) selon laquelle les chiens stérilisés sont plus à risque de développer un hémangiosarcome (HSA) a été testée. Des chiens (n = 5736) ont été diagnostiqués avec un HSA à partir d'une population de 2 106 324 chiens dans le VMDB de 1964 à 2003. Un design cas-témoin apparié sur l'âge et la période de temps fut créé pour des HSAs en général, cardiaques et spléniques. Une analyse de régression logistique fut effectuée incluant la race. Les femelles stérilisées avaient un ratio de cotes (OR) de 1,59 pour un HSA splénique, de 1,47 pour HSA cardiaque et de 1,72 pour un HSA en général. Les mâles castrés avaient un OR de 1,26 pour les HSA splénique et de 1,14 pour les HSA généraux comparativement aux mâles entiers. En contrôlant pour la période de temps et l'âge du patient, les données du VMDB soutiennent le fait que la stérilisation est associée avec le développement de HSA splénique et d'HSA en général autant chez les chiens que chez les chiennes, mais pas les HSA cardiaques avec un degré d'association moindre que décrit antérieurement.Message clinique clé :Cette étude cas-témoin confirme une association entre la stérilisation et le développement d'HSA et d'HSA splénique, mais pas d'HSA cardiaque, autant chez le mâle que chez la femelle. En contrôlant pour la période de temps au moment du diagnostic, le biais pour la pratique récente de stérilisation tôt dans la vie de l'animal est éliminé, ce qui suggère que la stérilisation hâtive n'est pas un déterminant principal de cet effet.(Traduit par Dr Serge Messier).


Assuntos
Doenças do Cão/epidemiologia , Doenças do Cão/etiologia , Hemangiossarcoma/epidemiologia , Hemangiossarcoma/veterinária , Animais , Estudos de Casos e Controles , Cães , Feminino , Masculino , Razão de Chances , Estudos Retrospectivos
2.
J Am Vet Med Assoc ; 233(6): 955-9, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18795860

RESUMO

OBJECTIVE: To determine associations between age, sex, breed, and month and year of admission and the diagnosis of lead toxicosis in cattle. DESIGN: Retrospective case-control study. Sample Population-Records of all cattle evaluated at North American veterinary teaching hospitals during the years 1963 to 2002, which were available through the Veterinary Medical Database. PROCEDURES: Logistic regression was used to evaluate the associations between postulated risk factors and the occurrence of lead toxicosis in cattle and predict the occurrence of the diagnosis of lead toxicosis in cattle. RESULTS: 413 cases of lead intoxication and 202,363 control cattle were identified and met the inclusion criteria. Cattle < 4 years of age were at increased risk for the diagnosis of lead intoxication relative to cattle > or = 4 years of age. Cattle > or = 2 months and < 6 months of age had the greatest risk for lead intoxication (odds ratio, 12.3). Angus cattle were at greater risk for toxicosis (odds ratio, 1.95), compared with other breeds. The risk of lead toxicosis was greater before 1985 (odds ratio, 1.94) than the risk thereafter. The risk of lead toxicosis diagnosis was greatest in the months of May, June, July, and August. CONCLUSIONS AND CLINICAL RELEVANCE: Lead toxicosis in cattle was associated with age < 4 years and the Angus breed. A seasonal pattern existed with peak occurrence in the late spring and summer. The occurrence of lead toxicosis has declined over time.


Assuntos
Cruzamento , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/epidemiologia , Intoxicação por Chumbo/veterinária , Fatores Etários , Animais , Estudos de Casos e Controles , Bovinos , Intervalos de Confiança , Demografia , Feminino , Intoxicação por Chumbo/diagnóstico , Intoxicação por Chumbo/epidemiologia , Modelos Logísticos , Masculino , Razão de Chances , Registros/veterinária , Estudos Retrospectivos , Fatores de Risco , Estações do Ano , Fatores Sexuais , Estados Unidos/epidemiologia
3.
J Am Vet Med Assoc ; 232(12): 1818-24, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18598150

RESUMO

OBJECTIVE-To evaluate prevalence of and risk factors for hip dysplasia (HD) and cranial cruciate ligament deficiency (CCLD) in dogs and determine change in prevalence over time. DESIGN-Cross-sectional study. ANIMALS-1,243,681 Dogs for which information was reported to the Veterinary Medical Database between 1964 and 2003. PROCEDURES-Information on breed, sex, and age was collected, and prevalences and odds ratios were calculated. RESULTS-Castrated male dogs were significantly more likely than other dogs to have HD (odds ratio [OR], 1.21), and castrated male (OR, 1.68) and spayed female (OR, 2.35) dogs were significantly more likely to have CCLD. Dogs up to 4 years old were significantly more likely to have HD (OR for dogs 2 months to 1 year old, 1.22; OR for dogs > 1 to 4 years old, 1.48), whereas dogs > 4 years old were significantly more likely to have CCLD (OR for dogs > 4 to 7 years old, 1.82; OR for dogs > 7 years old, 1.48). In general, large- and giant-breed dogs were more likely than other dogs to have HD, CCLD, or both. Prevalences of HD and CCLD increased significantly over the 4 decades for which data were examined. CONCLUSIONS AND CLINICAL RELEVANCE-Results suggested that sex, age, and breed were risk factors for HD, CCLD, or both in dogs and that prevalences of HD and CCLD have increased over time.


Assuntos
Ligamento Cruzado Anterior/anormalidades , Displasia Pélvica Canina/epidemiologia , Fatores Etários , Animais , Peso Corporal/fisiologia , Estudos Transversais , Cães , Feminino , Masculino , Razão de Chances , Linhagem , Prevalência , Fatores de Risco , Fatores Sexuais
4.
Biomed Sci Instrum ; 51: 40-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25996697

RESUMO

We report on an activity monitoring system for elderly persons living alone. Caregivers would like to know whether the person is talking during their daily activity. Our monitoring system consists of a recorder and a personal computer. The recorder, attached to the subject's chest, employs two microphones, a tri-axis accelerometer, two low-power amplifiers, a low-power microcomputer (MC) and a 2GB micro SD Memory Card (SDMC). One of the microphones is set in the direction of the chest for recording the person's voice, and the other microphone is set to the opposite side for recording surrounding sound. The microphone outputs and the accelerometer outputs are sent to the MC’s 10 bit analog to digital converters and sampled at 4000Hz and 50Hz, respectively. The MC detects the length of the conversation time from the microphone outputs, and the posture and behavior are detected from the accelerometer outputs every 5 seconds. The detected time, posture and behavior are stored in the SDMC. The data can be downloaded from the memory card and sent to appropriate stations. The system is used to monitor the health and physical conditions during daily life of elderly persons living alone.

5.
Biomed Sci Instrum ; 50: 397-402, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25405450

RESUMO

We have developed an ultrasonic stride length measuring system for analyzing the human gait. All elements of the system are quite small and each fit into an appropriate package. An ultrasonic transmitter, a digital compass, a radio transmitter and a microcontroller are attached to the subject’s heel on the right shoe and in the direction of the left shoe. Two ultrasonic receivers, a digital compass, a radio receiver, a microcontroller and a 1GB SD memory card are installed on the left shoe. The ultrasonic receivers are attached to the toe and heel in the direction of the right shoe. The walking direction is thus detected by the compass attached on the right and left shoes, respectively. The stride length is detected by the difference between the radio wave and ultrasonic propagation velocities. The stride length is corrected by the detected walking direction, and then the corrected stride length is stored in the SD memory card. When downloaded, the memory card gives the accurate stride length which then is used to characterize the subject’s gait during daily activity.

6.
Biomed Sci Instrum ; 49: 68-73, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23686183

RESUMO

We have developed an ultra-flexible skin electrode to monitor a patient’s electrocardiogram (ECG) during daily activity. This electrode consists of a 1.5 micrometer thick polyester film printed with electro-conductive paint. The electrode is attached to the outside of a polyethylene bag filled with a high viscoelastic fluid. When the electrode is placed securely on the skin, it correspondingly changes its shape, and electrode movement artifact is thereby decreased. The electrode improves long-term recording of the ECG by maintaining capacitance-coupled impedance between the electrode and the skin.

7.
Biomed Sci Instrum ; 49: 62-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23686182

RESUMO

Amyotrophic lateral sclerosis is a progressive degeneration of motor neurons. Patients with the disease lose their ability to speak and to use their hands as the disease progresses. We have developed a new electronic communication system that enables communication by blinking of the eyes. The system consists of a light emitting diode (LED), two silicone rubber electrodes, an electrooculogram (EOG) recorder, a microcontroller, a sound reproduction board, a pillow speaker and a low power mobile phone. The two silicone rubber electrodes record the EOG induced by blinking the eyes synchronized with LED flashing. The EOG is amplified by the EOG recorder. The microcontroller detects the blinking from the amplified EOG, and then their meanings are confirmed by voice. After that, the patient’s intention is transmitted to the nurse by a low power mobile phone so the care giver is kept in the loop.

8.
Biomed Sci Instrum ; 49: 74-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23686184

RESUMO

We have developed a drip infusion solution monitoring system for hospital and care facility use that is much more accurate than our previous reported system. The system consists of two electrodes and an acceleration sensor. The electrodes, which are wrapped around the infusion supply polyvinyl chloride (PVC) tube from the solution bag and the drip chamber, measure the growth and fall of each drop of infusion solution. The drip rate is detected from the fall of each drop. In addition, the acceleration sensor is attached to the outside of the drip chamber and detects the tilt angle of that chamber. The injected infusion solution amount is calculated by the infusion solution quantity per one drop and the drip rate. However, the quantity changes depend on the tilt angle of the drip chamber. The quantity of each drop is then corrected by the tilt angle of the drip chamber.

9.
Biomed Sci Instrum ; 48: 282-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22846295

RESUMO

We have developed a new ultrasonic stride length measuring system for analyzing the human gait. An ultrasonic transmitter, a radio transmitter, a pressure sensor and microcontroller are attached to the subject’s heel on the right shoe and in the direction of the left shoe. Two ultrasonic receivers, a radio receiver, a microcontroller and a 1GB SD memory card are installed on the left shoe. Ultrasonic receivers are attached to the toe and heel, in the direction of the right shoe. When the right foot contacts the ground, its heel-mounted ultrasonic and radio transmitters simultaneously transmit to the left shoe. However, radio propagation velocity is far faster than ultrasonic velocity. Therefore, the radio wave acts as a start signal to the radio receiver of the left shoe, indicating the start of ultrasound transmission from the right shoe. Upon receiving the start signal, the microcontroller timer starts to measure each ultrasound propagation time from the right shoe to the left shoe. Distance between right and left shoes is calculated with the time and ultrasound velocity and stored in the SD memory card. Stride length is calculated with a cosine function, by using the obtained distances and the distance between the toe and heel of the left shoe, by a conventional computer. The stride length can then be used for many characterizations of the subject’s gait.

10.
Biomed Sci Instrum ; 48: 310-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22846299

RESUMO

We have developed a drip infusion warning system for hospital and care facility use. In general, two kinds of infusion sets are used, which have drop factors of either 20 or 60. (A drop factor is the number of drops to deliver 1 ml of infusion solution.) When an infusion set having a 20 drop factor is used, the number of drops per drip is adjusted to 20. If an infusion set has a drop factor of 60, then the infusion volume rate becomes three times as much. This may result in legal consequences if the patient is injured. In this study, a drip infusion warning system detects whether the infusion is a 20 or a 60 drop factor. The system consists of two electrodes, one wrapped around the infusion supply polyvinyl-chloride tube, and another one around the drip chamber. The electrical impedance between two electrodes is changed by the growth and fall of each drop of fluid. The drop growth length especially changes, depending on the type of infusion set used. Therefore, the two types of infusion sets can be identified by monitoring the drop length. Our warning system detects whether the infusion set used corresponds to a 20 or 60 drop factor, so the system can reduce human errors.

11.
Biomed Sci Instrum ; 47: 153-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21525613

RESUMO

We have been searching for a suitable frequency range for an electrical impedance measurement infusion solution drip monitoring system, which we have previously reported. This electrical impedance, which is formed between two electrodes wrapped around the infusion supply polyvinyl-chloride tube and around the drip chamber, is changed by the growth and fall of each drop of fluid. Thus, the drip rate can be detected by measuring this impedance. However, many different kinds of infusion solutions such as glucose, amino acid, soya oil, and lactated Ringer’s solution are used in hospitals and care facilities. Therefore, it was necessary to find a suitable frequency for driving the capacitance-change sensor with a wide range of infusion solutions. In this study, the sensor electrical impedance change of 16 infusion solutions was measured from 1 kHz up to 1 MHz. The drip impedance produced by 5% glucose solution, 10% glucose solution and soya oil indicated the maximum sensor output change at 10 kHz, 20 kHz, and 70 kHz, respectively. The other 13 infusion solutions increased up to 10 kHz, and were constant from 10 kHz to 1 MHz. However, the growth, fall, and drip rate of the drops of all the infusion solutions were monitored by measuring the impedance change from 10 kHz to 30 kHz. Our experimental results indicated that most suitable excitation range for the infusion monitoring system is from 10 kHz to 30 kHz. Thus, we can now “fine-tune” the system for optimal sensing.

12.
Biomed Sci Instrum ; 47: 160-4, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21525614

RESUMO

We have developed a telemedicine system to monitor a patient’s electrocardiogram (ECG) and heart sounds (PCG) during daily activity. The complete system, consisting of an ECG recorder, an accelerometer and a 2.4 GHz low power mobile phone, is mounted on three chest sensing electrodes. The accelerometer records the PCG produced by closing of the mitral and aortic valves (S1 and S2). The sampled ECG and PCG are stored in the system for two minutes and continuously updated. When a patient feels heart discomfort such as angina or an arrhythmia, he/she pushes the data transmission switch on the system. The ECG and PCG for the next two minutes are stored in the system, and then the system then sends the four minutes of stored data directly to a hospital server computer via the 1.9 GHz low power mobile phone. These data are stored on the server and then downloaded to the physician’s Java configured mobile phone. The physician can then check the patient’s cardiac condition, regardless of patient or physician locations, and then take appropriate actions.

13.
J Am Vet Med Assoc ; 239(7): 960-5, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21961635

RESUMO

OBJECTIVE-To identify the most common cutaneous neoplasms in dogs and evaluate breed and age distributions for selected neoplasms. DESIGN-Retrospective epidemiological study. SAMPLE-Records available through the Veterinary Medical Database of dogs examined at veterinary teaching hospitals in North America between 1964 and 2002. PROCEDURES-Information on tumor type and patient breed and age was collected. Incidence and odds ratios with 95% confidence intervals were calculated. RESULTS-Records of 1,139,616 dogs were reviewed. Cutaneous neoplasms were diagnosed in 25,996 of these dogs; records for the remaining 1,113,620 dogs did not indicate that cutaneous neoplasms had been diagnosed, and these dogs were considered controls. The most frequent age range for dogs with cutaneous neoplasms was 10 to 15 years. Lipoma, adenoma, and mast cell tumor were the most common skin tumor types. CONCLUSIONS AND CLINICAL RELEVANCE-Results supported previously reported data regarding cutaneous neoplasia in dogs but provided updated information on the most common skin tumors and on age and breed distributions.


Assuntos
Doenças do Cão/epidemiologia , Predisposição Genética para Doença , Neoplasias Cutâneas/veterinária , Envelhecimento , Animais , Doenças do Cão/genética , Cães , Razão de Chances , Estudos Retrospectivos , Neoplasias Cutâneas/classificação , Estados Unidos/epidemiologia
14.
Biomed Sci Instrum ; 46: 81-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20467076

RESUMO

We have developed a non-intrusive safety monitoring system which can measure respiration and body movements of solitary-living elderly people while they are in their home bathroom. These physiological variables are monitored with a 40 kHz ultrasonic transmitter and four receivers. The ultrasonic transmitter diffuses an ultrasonic wave throughout the room. The diffusion pattern of this inaudible sonic energy is changed by body movements and respiration, therefore modulating the amplitude of the received ultrasonic signal. The received ultrasonic signals are demodulated by envelope detection circuits. Band-pass filters detect respirations and body movements from the envelope detection circuit outputs. These detected signals are added and used to monitor whether the elderly person is safe or not safe, while in their bathroom. When the microcomputer cannot detect body movement or respiration, it alerts the persons caregiver, via a low power personal handy phone system.

15.
Biomed Sci Instrum ; 46: 110-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20467081

RESUMO

A new drip infusion solution monitoring system has been developed for hospital and care facility use. The system detects and counts the fall of each drip chamber drop of fluid. Two non-contacting copper foil electrodes are used; one wrapped around the infusion supply polyvinyl-chloride tube under the solution bag and another around the drip chamber, forming two capacitors. Drip infusion fluids have electrical conductivity, so the capacitors are a series-connected electrical impedance. A thirty kHz sine wave is applied to the infusion tube electrode and the capacity-coupled signal on the drip chamber electrode is the transducer output. When an infusion fluid drop is forming, its diameter, and therefore drip chamber capacitance, are increasing, causing change in the output signal. When the drop reaches sufficient diameter to fall, the drip chamber capacitance decreases, which briefly returns the output signal to baseline. Therefore, the growth, fall, and drip rate of each drop of fluid can be detected from the output signal waveform. The system also has advantages of being insensitive to ambient light type and intensity, and detects when the infusion bag is empty.

16.
Biomed Sci Instrum ; 46: 87-93, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20467077

RESUMO

UNLABELLED: An ultrasonic physical and care monitoring system has been developed for monitoring the physiological parameters of body movement, heart contraction, and respiration of patients on low-repulsion, anti-decubitus (anti-bedsore) hospital beds. These beds, of several designs, are intended to reduce pressure on the body surface of immobilized patients, in order to prevent decubitus ulcers, which are often fatal. Since low-repulsion mattresses lack conventional springs, padding and air space, this system employs a polyvinyl chloride tube under the mattress, which has a 40 kHz ultrasonic transmitter and receiver at its ends. The shape of the tube is altered by body, heart and respiratory movements, which modulate the complex diffusion of the ultrasonic energy in the tube. As a result, the amplitude of the received ultrasonic signal is movement-modulated. This received signal is then demodulated and low, high and band pass filtered, to yield the three separate patient movement parameters. These are recorded and can be real-time computer analyzed, to activate alarms if the patient has not moved, or not been moved by the staff, within programmable time limits. These data may also be employed to indicate relative patient medical condition. A major system advantage is that it does not require any body-attached sensors. KEYWORDS: Ultrasound, cardiac pulse, respiration, body movement, low-repulsion mattress, decubitus ulcer.

17.
Biomed Sci Instrum ; 45: 424-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19369800

RESUMO

We have developed a heart rate, respiration rate, posture, behavior and activity data acquisition system for monitoring certain health and activity features during daily life. The recording system consists of one tri-axis accelerometer, six low-power active filters, a low-power 8-bit microcontroller (MC) and a 128MB compact flash memory (CFM). The system is attached to the subject's chest and can simultaneously measure dynamic and static acceleration forces. The microcontroller continuously monitors X, Y and Z axis large dynamic acceleration forces that reveal patient movement. If the patient is moving, the MC detects whether the patient is changing body position, walking or running. If the patient is at rest, the MC detects heart rate and respiration rates from the X axis small dynamic acceleration force. The patient's posture is detected from the X and Y axis static acceleration forces. These detected signals are stored into the CFM, and then the data are downloaded to the laptop computer and used for monitoring the certain of the patient's health conditions.

18.
Biomed Sci Instrum ; 45: 430-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19369801

RESUMO

We have developed a remotely accessible telemedicine system for monitoring a patient's electrocardiogram (ECG). The system consists of an ECG recorder mounted on chest electrodes and a physician's laptop personal computer. This ECG recorder is designed with a variable gain instrumentation amplifier; a low power 8-bit single-chip microcomputer; two 128KB EEPROMs and 2.4 GHz low transmit power mobile telephone. When the physician wants to monitor the patient's ECG, he/she calls directly from the laptop PC to the ECG recorder's phone and the recorder sends the ECG to the computer. The electrode-mounted recorder continuously samples the ECG. Additionally, when the patient feels a heart discomfort, he/she pushes a data transmission switch on the recorder and the recorder sends the recorded ECG waveforms of the two prior minutes, and for two minutes after the switch is pressed. The physician can display and monitor the data on the computer's liquid crystal display.

19.
J Cancer Epidemiol ; 2009: 591753, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20445802

RESUMO

The Surveillance Epidemiology and End Results data demonstrate that the risk of non-Hodgkin lymphoma is lower for women, but that the incidence increases after fifty years of age, at which menopause is regularly reached, suggesting that female hormones may be protective for NHL. This study examines the influence of sex on lymphoma risk in a relevant large animal model. Records for dogs in the Veterinary Medical Database were analyzed from 1964 to 2002. Risk ratios were calculated to evaluate associations between sex, neutering status, and lymphoma occurrence. A total of 14,573 cases and 1,157,342 controls were identified. Intact females had a significantly lower risk of developing lymphoma, Odds Ratio 0.69 (0.63-0.74) with a P < .001. We conclude that there is a sex effect on NHL risk in dogs similar to humans. We hypothesize that the hormone levels of intact females lower the risk of NHL. The possibility of a protective role of endogenous estrogens in the etiology of NHL should be investigated.

20.
Biomed Sci Instrum ; 44: 507-12, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19141966

RESUMO

We have developed a non-invasive system for monitoring cardiac vibrations, respiration and body movement of in-bed hospitalized patients and elderly people who need constant care. These physiological parameters are recorded by 40 kHz ultrasonic transmitter and receiver, which are installed into the bed mattress. The ultrasonic transmitter diffuses an ultrasonic wave into the mattress. The diffusion of the ultrasonic energy is changed by mattress shape variations, which modulate the amplitude of the received ultrasonic signal. The amplitude is also modulated by physiological parameters such as heart pulse, respiration and body movement. The received ultrasonic signal is demodulated by an envelope detection circuit, and the physiological parameters are detected by low, high and band pass filters.

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