Objective:To provide a reliable basis for the objective evaluation of the kinetic visual acuity (KVA) of navy pilots through a comprehensive analysis of the KVA test results among 190 navy pilots.Methods:We measured both the monocular and binocular KVA of 190 navy pilots at the Naval Medical Center with a DS-3 dynamic vision apparatus. The vision target velocity was set at 30 km/h. The hole-in-the card was also performed to examine the dominant eyes of the navy pilots.Results:The static visual acuity of all pilots tested was ≥1.0, but 6.05% of the monocular KVA and 4.74% of the binocular KVA were <1.0. There were no statistically significant differences in the binocular KVA ( P=0.07) and monocular KVA ( P=0.16) of the navy pilots of different age groups. The KVA of the left eyes was slightly higher than that those of the right eyes, but without statistical significance ( P=0.168). The KVA of the dominant eyes were slightly lower than the non-dominant eyes, but without statistical significance either ( P=0.284). The monocular KVA was significantly lower than the binocular KVA ( P<0.05). Conclusion:In the health exam for navy pilot recruitment and pilot health assessment, it is advisable for candidates/pilots to take a KVA test in addition to a static visual acuity test. The age of the examined navy pilots has no significant impact on their KVA. The monocular KVA is significantly lower than the binocular KVA. The KVA of the left eyes and the right eyes is relatively balanced, and the advantage of dominant eyes is not reflected in the KVA test.

Objective:To provide a reliable basis for the objective evaluation of the kinetic visual acuity (KVA) of navy pilots through a comprehensive analysis of the KVA test results among 190 navy pilots.Methods:We measured both the monocular and binocular KVA of 190 navy pilots at the Naval Medical Center with a DS-3 dynamic vision apparatus. The vision target velocity was set at 30 km/h. The hole-in-the card was also performed to examine the dominant eyes of the navy pilots.Results:The static visual acuity of all pilots tested was ≥1.0, but 6.05% of the monocular KVA and 4.74% of the binocular KVA were <1.0. There were no statistically significant differences in the binocular KVA ( P=0.07) and monocular KVA ( P=0.16) of the navy pilots of different age groups. The KVA of the left eyes was slightly higher than that those of the right eyes, but without statistical significance ( P=0.168). The KVA of the dominant eyes were slightly lower than the non-dominant eyes, but without statistical significance either ( P=0.284). The monocular KVA was significantly lower than the binocular KVA ( P<0.05). Conclusion:In the health exam for navy pilot recruitment and pilot health assessment, it is advisable for candidates/pilots to take a KVA test in addition to a static visual acuity test. The age of the examined navy pilots has no significant impact on their KVA. The monocular KVA is significantly lower than the binocular KVA. The KVA of the left eyes and the right eyes is relatively balanced, and the advantage of dominant eyes is not reflected in the KVA test.

Objective To study the analgesic effect of repeated hyperbaric oxygen (HBO) exposures and explore the mechanism involving neural nitric oxide synthase ( nNOS), nitric oxide ( NO) and γ-aminobutyric acid (GABA).Methods The animal pain model was established and the animals were randomly divided into the HBO group, the hyperbaric air ( HBA) group, the normobaric air (NBA) group and the normobaric oxygen ( NBO) group, and were exposed repeatedly to either HBO or air .The chamber was ventilated with 100％ O2 for 5 min, then, the chamber was pressurized to 0.35 MPa at a rate of 0.10 MPa/min.At the pressure of 0.35 MPa, the chamber was again ventilated with oxygen /air for 60 minutes, and then, was decompressed at a rate of 0.10 MPa/min.The animals were exposed in the chamber one session a day for a succession of 4 days.Analgesic effect was evaluated by abdominal contraction test , and nitrate reductase assay was used to determine the expression levels of NO and NOS in the brain tissue and the spinal cord.NOS inhibitors were given by i.c.v injection to measure the effect of NOS on the analgesic effect of HBO.The nNOS + neurons and glatamic acid decarboxylase ( GAD) positive ( GAD +) neurons in the periaqueductal gray ( PAG) were labeled by fluorescopy.Results Repeated HBO treatment induced a biphasic analgesic effect, including: (1) early analgesia which was displayed an hour after HBO exposure and lasted for about 8 hours; (2) late analgesia which was displayed one day after HBO exposure , reached peak one week later and lasted for about 3 weeks.Three hours after the termination of last HBO exposure , medication of the non-specific NOS inhibitor N′-Nitro-L-arginine-methyl ester hydrochloride ( L-NAME ) and nNOS inhibitor S-methyl-L-thiocitrulline (SMTC) could obviously inhibit early analgesic effect .L-NAME and SMTC could significantly inhibit late analgesia .One hour after HBO exposure, the levels of NO and nNOS in the brain tissue and spinal cord were considerably elevated .The late analgesic effect of HBO significantly decreased , when CGP35348 was injected in the lateral ventricle 7 days after HBO treatment.Immunofluorescence indicated that there was a co-localization between nNOS + neurons and GAD + neurons in the PAG.Conclusions Repeated 4 HBO exposures induced a double -phased analgesia.Initial analgesic effect displayed one hour after HBO treatment, involving activation of nNOS, while late analgesic effect emerged one day after HBO exposure , with the interaction between nNOS and GABA B receptors.

Objective To explore the entrainment effect of different light regimens on the circadian rhythms of peripheral blood immune cells in mice .Methods One hundred and forty-four male C57BL/6 mice were kept under the 12 h-light and 12 h-dark cycle for 4 weeks.Then, the animals were randomly divided into 3 groups.The 24 animals in group 1 were treated with the former light regimen , the 60 animals in group 2 were kept in the light regimen of phase advance 12 hours, simulating eastward flight, and another 60 animals in group 3 were kept in the light regimen of phase delay 12 hours, simulating westward flight.Peripheral blood samples of the animals in group 1 were collected respectively one day before and 21 days after changes of light regimens, and blood samples of the animals in group 2 and 3 were collected on different days (i.e.day 2, 4, 7, 14 and 21) after changes of light regimens .Peripheral blood samples were taken at 4 different timepoints in 24 hours ( i.e.9 :00, 15:00, 21 :00 and 3 :00).Detections were made in immune cells , including the numbers of leukocytes, the percentage of lymphocytes , the percentage of CD4 +lymphocytes, the percentage of CD8 +lymphocytes, as well as monocyte and granulocyte counts .Finally, the circadian rhythms of differentimmune cells were evaluated in the animals of different groups .Results The immune cells in the C57BL/6 mice displayed different circadian rhythms under the 12 h-light and 12 h-dark cycle for 4 weeks.Under the new light regimens, the circadian rhythms of immune cells were entrained .It took 2 weeks for the animals of the simulated westward flight phase delay group to entrain the circadian rhythm , while the rate of entrainment for the animals of the simulated eastward flight phase delay group was 3 weeks.Conclusions Under the 12 h-light and 12 h-dark cycle, immune cells in the peripheral blood displayed a rise and fall circadian rhythm , which might facilitate the balance of the immune system .However, under the new light regimens, the circadian rhythms of different immune cells in the peripheral blood were entrained , with the entrainment rate of immune cells in the phase delay group being faster than that of the phase advance group .

Objective To discuss the effects of ship cabin color on the identification of instrument board by the ship crew.Methods The crew instrument identification system (HYS-2000) was applied in the study.The identification ability of 10 volunteers working in the environment of 6 different color matches was detected respectively at day 1, 4, 7, 10, 13, 16, 19 and 22.TOPSIS (technique for order preference by similarity to an ideal solution) and clustering analysis were used for comprehensive analysis of the crew ability in the identification of 6 different color matches.Results The selected color environment (CE), the simulated navigation time (SNT) and the interaction between CE and SNT seemed to have no significant effects on the accuracy of instrument identification , and there was no statistical significance when comparisons were made between them.(P >0.05).However, CE, SNT and the interaction between CE and SNT had significant effects on the response time of instrument identification by the subjects , and statistical significance could be noted, when comparisons were made between them (P <0.01).Results indicated that the priority ordering by TOPSIS was CE3, CE2, CE6, CE5, CE4 and CE1, and clustering analysis showed that by superiority CE 3 and CE2 belonged to the first type, CE6 belonged to the second type, CE4 belonged to the third type and CE4, CE1 belonged to the fourth type.Conclusions The ship cabin with cold color and low saturation CE with color brightness decreasing from top to bottom had lower effects on the crew identification of the instrument board . With this reason, the best ship cabin color matching was CE3 and CE2.

Objective To study the analgesic effect of repeated hyperbaric oxygen (HBO) exposures and explore the mechanism involving neural nitric oxide synthase ( nNOS), nitric oxide ( NO) and γ-aminobutyric acid (GABA).Methods The animal pain model was established and the animals were randomly divided into the HBO group, the hyperbaric air ( HBA) group, the normobaric air (NBA) group and the normobaric oxygen ( NBO) group, and were exposed repeatedly to either HBO or air .The chamber was ventilated with 100％ O2 for 5 min, then, the chamber was pressurized to 0.35 MPa at a rate of 0.10 MPa/min.At the pressure of 0.35 MPa, the chamber was again ventilated with oxygen /air for 60 minutes, and then, was decompressed at a rate of 0.10 MPa/min.The animals were exposed in the chamber one session a day for a succession of 4 days.Analgesic effect was evaluated by abdominal contraction test , and nitrate reductase assay was used to determine the expression levels of NO and NOS in the brain tissue and the spinal cord.NOS inhibitors were given by i.c.v injection to measure the effect of NOS on the analgesic effect of HBO.The nNOS + neurons and glatamic acid decarboxylase ( GAD) positive ( GAD +) neurons in the periaqueductal gray ( PAG) were labeled by fluorescopy.Results Repeated HBO treatment induced a biphasic analgesic effect, including: (1) early analgesia which was displayed an hour after HBO exposure and lasted for about 8 hours; (2) late analgesia which was displayed one day after HBO exposure , reached peak one week later and lasted for about 3 weeks.Three hours after the termination of last HBO exposure , medication of the non-specific NOS inhibitor N′-Nitro-L-arginine-methyl ester hydrochloride ( L-NAME ) and nNOS inhibitor S-methyl-L-thiocitrulline (SMTC) could obviously inhibit early analgesic effect .L-NAME and SMTC could significantly inhibit late analgesia .One hour after HBO exposure, the levels of NO and nNOS in the brain tissue and spinal cord were considerably elevated .The late analgesic effect of HBO significantly decreased , when CGP35348 was injected in the lateral ventricle 7 days after HBO treatment.Immunofluorescence indicated that there was a co-localization between nNOS + neurons and GAD + neurons in the PAG.Conclusions Repeated 4 HBO exposures induced a double -phased analgesia.Initial analgesic effect displayed one hour after HBO treatment, involving activation of nNOS, while late analgesic effect emerged one day after HBO exposure , with the interaction between nNOS and GABA B receptors.

Objective To explore the entrainment effect of different light regimens on the circadian rhythms of peripheral blood immune cells in mice .Methods One hundred and forty-four male C57BL/6 mice were kept under the 12 h-light and 12 h-dark cycle for 4 weeks.Then, the animals were randomly divided into 3 groups.The 24 animals in group 1 were treated with the former light regimen , the 60 animals in group 2 were kept in the light regimen of phase advance 12 hours, simulating eastward flight, and another 60 animals in group 3 were kept in the light regimen of phase delay 12 hours, simulating westward flight.Peripheral blood samples of the animals in group 1 were collected respectively one day before and 21 days after changes of light regimens, and blood samples of the animals in group 2 and 3 were collected on different days (i.e.day 2, 4, 7, 14 and 21) after changes of light regimens .Peripheral blood samples were taken at 4 different timepoints in 24 hours ( i.e.9 :00, 15:00, 21 :00 and 3 :00).Detections were made in immune cells , including the numbers of leukocytes, the percentage of lymphocytes , the percentage of CD4 +lymphocytes, the percentage of CD8 +lymphocytes, as well as monocyte and granulocyte counts .Finally, the circadian rhythms of differentimmune cells were evaluated in the animals of different groups .Results The immune cells in the C57BL/6 mice displayed different circadian rhythms under the 12 h-light and 12 h-dark cycle for 4 weeks.Under the new light regimens, the circadian rhythms of immune cells were entrained .It took 2 weeks for the animals of the simulated westward flight phase delay group to entrain the circadian rhythm , while the rate of entrainment for the animals of the simulated eastward flight phase delay group was 3 weeks.Conclusions Under the 12 h-light and 12 h-dark cycle, immune cells in the peripheral blood displayed a rise and fall circadian rhythm , which might facilitate the balance of the immune system .However, under the new light regimens, the circadian rhythms of different immune cells in the peripheral blood were entrained , with the entrainment rate of immune cells in the phase delay group being faster than that of the phase advance group .

Objective To discuss the effects of ship cabin color on the identification of instrument board by the ship crew.Methods The crew instrument identification system (HYS-2000) was applied in the study.The identification ability of 10 volunteers working in the environment of 6 different color matches was detected respectively at day 1, 4, 7, 10, 13, 16, 19 and 22.TOPSIS (technique for order preference by similarity to an ideal solution) and clustering analysis were used for comprehensive analysis of the crew ability in the identification of 6 different color matches.Results The selected color environment (CE), the simulated navigation time (SNT) and the interaction between CE and SNT seemed to have no significant effects on the accuracy of instrument identification , and there was no statistical significance when comparisons were made between them.(P >0.05).However, CE, SNT and the interaction between CE and SNT had significant effects on the response time of instrument identification by the subjects , and statistical significance could be noted, when comparisons were made between them (P <0.01).Results indicated that the priority ordering by TOPSIS was CE3, CE2, CE6, CE5, CE4 and CE1, and clustering analysis showed that by superiority CE 3 and CE2 belonged to the first type, CE6 belonged to the second type, CE4 belonged to the third type and CE4, CE1 belonged to the fourth type.Conclusions The ship cabin with cold color and low saturation CE with color brightness decreasing from top to bottom had lower effects on the crew identification of the instrument board . With this reason, the best ship cabin color matching was CE3 and CE2.

Objective To investigate circadian rhythm of four genes (bmal1,clock,cry1,per1) in mouse peripheral white blood cells under the 12 h-light and 12 h-dark cycle (12L/12D) condition.Methods Forty-eight male mice were kept under the light regime of 12L/12D for four weeks.According to random number table,they were randomly and averagely divided into 6 groups.Then,the blood samples were taken and white blood cells were separated every four hours in a circadian day (9:00,13:00,17:00,21:00,1:00 and 5:00).The total RNA was extracted from the white blood cells and the mRNA level of each gene was quantified by real-time polymerase chain reaction (real-time PCR).The data were fitted by cosine function for getting the rhythm.The difference between apex and trough was analyzed by one-ANOVA.Results Under the light regime of 12L/12D,the four genes in peripheral white blood cells showed a significant circadian oscillation with different apex and trough.The apexes of four genes were higher than the troughs (P＜0.01).The equation fitted apex phase of clock gene was at about 5:00,compared to the apex time of the other three genes were at about 13:00-15:00.The apex time of clock mRNA was ahead of brnal1,and the apex and amplitude of it were higher than those of brnal1.However,the mRNAs of cry1 and per1 showed a similar apex time and apex level.Conclusions The findings demonstrate that the expression of the four genes in white blood cells shows an obvious circadian rhythm.It seems that clock plays more important role than bmal1 in the positive regulation,and cry1 and per1 play a similar role in negative regulation.This result will not only be helpful to understand the circadian fluctuation of immune function,but also to provide a target for implementing diagnosis and therapy of immune disorders.Further study is needed to elucidate the control effect of these genes in different immune cells in peripheral blood.

Objective To analyze and evaluate the effect of ship cabin color matching on the human physiological parameters.Methods Ten healthy male volunteers,with an age range of 19-31 and normal visual acuity and color vision,were all trainees recruited for the study.Heart rate,systolic pressure,diastolic pressure,contrast visual acuity and contrast visual sensitivity of the trainees were determined under 6 different cabin colors.Color codes were put in the order of 2#,6#,5#,4#,3# and 1# in accordance with the color warmth,with 2# being the cold color,6# the sub-cold color,5# the neutral color with cold deflection,4# the neutral color with warm deflection,2# the sub-warm color and 1 # the warm color.The test time cycle of each color scheme was 21 days.The effects of 6 cabin color schemes on the physiological parameters of the trainees were analyzed and evaluated by using TOPSIS (technique for order preference by similarity to an ideal solution) and cluster analysis.Results (1) Heart rate,systolic pressure and diastolic pressure of the trainees did not change with the changes in color scheme (P ＞ 0.05).In the same color scheme,heart rate,systolic pressure and diastolic pressure all fluctuated within normal ranges,without statistical significance (P ＞ 0.05).(2) In the 6 color schemes,average contrast visual acuity fluctuated within the ranges of 0.01-0.03.In the 3# color scheme,contrast visual acuity was the highest (4.98 ± 0.06),while contrast visual acuity in the 1 # color scheme was the lowest(4.95 ± 0.05).No statistical significance in contrast visual acuity could be seen in 6 color schemes(P ＞0.05).(3)In six different color environment schemes,there was statistical significance in contrast visual sensitivity,when the trainees were at 0.6 and 1.2 cycles per degree (P ＜0.05 and P ＜0.01).However,no statistical significance in contrast visual sensitivity could be noted at 2.4,4.8 and 9.6 cycles per degree(P ＞ 0.05).Conclusions Generally,heart rate,systolic pressure,diastolic pressure and contrast visual acuity of the trainees did not change with the changes in color schemes,while contrast visual sensitivity changed with the changes in color schemes of the cabin environment.The optimized sequence order of the 6 color schemes was 5#,6#,1#,3#,4# and 2#.The color scheme that had the least effect on the physiological parameters of the trainees was color scheme 5#,the neutral color with cold deflection.