[Research on the protective effect of hearing protective device for workers exposed to noise in a motor manufacturing enterprise].

Objective: To understand the current situation of noise hazard in a motor manufacturing enterprise, and to explore the protective effect of workers wearing hearing protective device and its possible influencing factors. Methods: In November 2021, a total of 179 noise workers wearing hearing protective devices in a motor manufacturing company in a city were selected as research objects. Personal attenuation rating (PAR) of workers wearing hearing protective devices was measured. Baseline PAR was analyzed for different subgroups of basic demographic information, noise exposure, and the use of hearing protective devices to evaluate the effect of the intervention. Baseline PAR was compared using nonparametric tests. Results: There were 179 workers from 35 positions in 4 types of work, and the over-standard noise rate was 51.2% (42/82), among which the noise exposure intensity of motor equipment debugging workers was the highest [94.4 dB (A) ]. Compared the baseline PAR of different characteristics, it was found that the baseline PAR of male workers, workers whose daily noise exposure time were <8 h, workers who had used the hearing protective devices for 10 to 14 years, and workers who thought the hearing protective devices were comfortable were all higher, and the differences were statistically significant (P<0.05). Baseline PAR passing rate was 43.0% (77/179), and PAR of 102 workers who did not pass baseline test increased from 0 (0, 3) dB before intervention to 14 (12, 16) dB after intervention, with statistical significance (P<0.05) . Conclusion: The noise hazard in this motor manufacturing enterprise is serious, and the protective effect of workers wearing hearing protective devices is not good. Gender, daily noise exposure time, years and comfort of wearing hearing protective device are the possible influencing factors of poor protective effect.

Coherent Picture on the Pure Spin Transport between Ag/Bi and Ferromagnets.

In a joint effort of both experiments and first-principles calculations, we resolve a hotly debated controversy and provide a coherent picture on the pure spin transport between Ag/Bi and ferromagnets. We demonstrate a strong inverse Rashba-Edelstein effect (IREE) at the interface in between Ag/Bi with a ferromagnetic metal (FM) but not with a ferromagnetic insulator. This is in sharp contrast to the previously claimed IREE at Ag/Bi interface or inverse spin Hall effect dominated spin transport. A more than one order of magnitude modulation of IREE signal is realized for different Ag/Bi-FM interfaces, casting strong tunability and a new direction for searching efficient spintronics materials.

Decision analysis supports the use of drain amylase-based enhanced recovery method after esophagectomy.

Postesophagectomy anastomotic leak is a common postsurgical complication. The current standard method of detecting leak is esophagram usually late in the postoperative period. Perianastomotic drain amylase level had shown promising results in early detection anastomosis leak. Previous studies have shown that postoperative day 4 amylase level is more specific and sensitive than esophagram. The purpose of this study is to determine if implementing a drain amylase-based screening method for anastomotic leak can reduce length of stay and hospital cost relative to a traditional esophagram-based pathway. The drain amylase protocol we propose uses postoperative day 4 drain amylase level to direct the initiation of PO intake and discharge. We designed a decision analysis tree using TreeAge Pro software to compare the drain amylase-based screening method to the standard of care, the esophagram. We performed a retrospective review of postesophagectomy patients from a tertiary academic medical center (University hospital Cleveland medical center) where amylase level was measured routinely postoperatively. The patients were separated into amylase-based pathway group and the standard of care group based on their postop management. The length of stay, costs, complications, and leak rate of these two groups were used to inform the decision analysis tree. In the base-case analysis, the decision analysis demonstrated that an amylase-based screening method can reduce the hospital stay by one day and reduced costs by ∼$3,000 compared to esophagram group. To take the variability of the data into consideration, we performed a Monte Carlo simulation. The result showed again a median saving of 0.71 days and ∼$2,500 per patient in hospital cost. A ballistic sensitivity analysis was performed to show that the sensitivity of postoperative day 4 amylase level in detecting a leak was the most important factor in the model. We conclude that implementing an amylase-based screening method for anastomotic leak in postesophagectomy patient can significantly reduce hospital cost and length of stay. This study demonstrates a novel protocol to improve postesophagectomy care. Based on this result, we believe a prospective multicenter study is appropriate.

[The development of ex vivo lung perfusion in lung transplantation].

The shortage of donor lung remains one of the major problem for lung transplantation. With the development of modern lung preservation and repair technique, increasing marginal lung donors have been re-assessed and finally utilized for transplantation. The ex vivo lung perfusion technique (EVLP) was designed and has been developed for evaluation and repair of the lung. Nowadays, the indication of EVLP and the standard of qualified donor lung have reached a consensus according to the foreign publications. The EVLP system could be classified into three categories: the Toronto technique, the Lund technique and Hannover-Madrid technique. The major differences between the Toronto technique and the other two technique are the open left atrium status, the use of Steen solution mixed with erythrocyte and the perfusion at flows correspondent to 100% of the donor predicted cardiac output. With the accumulating experience, researchers have tried to imply some drugs in the circulation, modify the ventilation gas and delivery of adenoviral vector gene in order to improve the lung quality. But these are still in the research phase. Recently, the portable EVLP device has been developed and the lung preservation, assessment and repair could be conducted during transportation. So it could prolong the preservation time and expand the transportation distance of donor lung.

Effects of fasting and feeding on the fast-start swimming performance of southern catfish Silurus meridionalis.

This study investigated the effects of fasting and feeding on the fast-start escape swimming performance of juvenile southern catfish Silurus meridionalis, a sit-and-wait forager that encounters extreme fasting and famine frequently during its lifespan. Ten to 30 days of fasting resulted in no significant change in most of the variables measured in the fast-start response except a 20-30% decrease in the escape distance during the first 120 ms (D120ms ) relative to the control group (48 h after feeding). The ratio of the single-bend (SB) response (lower energetic expenditure) to the double-bend (DB) response increased significantly from 0% in the control group to 75 and 82·5% in the 20 and 30 day fasting groups, respectively. Satiated feeding (25% of body mass) resulted in a significantly lower (36·6%) maximum linear velocity (Vmax ) and a significantly lower (43·3%) D120ms than in non-fed fish (control group, 48 h after feeding). Half-satiated feeding (12·5% of body mass), however, showed no significant effects on any of the measured variables of the fast-start response relative to control fish. It is suggested that the increase in the ratio of SB:DB responses with fasting in S. meridionalis may reflect a trade-off between energy conservation and maintaining high Vmax , while variables of fast-start performance were more sensitive to feeding than fasting might be an adaptive strategy to their foraging mode and food availability in their habitat.

An interspecific comparison between morphology and swimming performance in cyprinids.

Flow regimes are believed to be of major evolutionary significance in fish. The flow regimes inhabited by cyprinids vary extensively from still flow regimes to riptide flow regimes. To test (i) whether flow-driven swimming performance and relevant morphological differentiation are present among fish species and (ii) whether evolutionary shifts between high-flow and low-flow habitats in cyprinids are associated with evolutionary trade-offs in locomotor performance, we obtained data on both steady and unsteady swimming performance and external body shape for 19 species of cyprinids that typically occur in different flow regimes (still, intermediate and riptide). We also measured the routine energy expenditure (RMR) and maximum metabolic rate (MMR) and calculated the optimal swimming speed. Our results showed that fish species from riptide groups tend to have a higher critical swimming speed (Ucrit ), maximum linear velocity (Vmax ) and fineness ratio (FR) than fish from the other two groups. However, there was no correlation between the reconstructed changes in the steady and unsteady swimming performance of the 19 species. According to the phylogenetically independent contrast (PIC) method, the Ucrit was actively correlated with the MMR. These results indicated that selection will favour both higher steady and unsteady swimming performance and a more streamlined body shape in environments with high water velocities. The results suggested that steady swimming performance was more sensitive to the flow regime and that for this reason, changes in body shape resulted more from selective pressure on steady swimming performance than on unsteady swimming performance. No evolutionary trade-off was observed between steady and unsteady swimming performance, although Ucrit and MMR were found to have coevolved. However, a further analysis within each typically occurring habitat group suggested that the trade-off that may exist between steady and unsteady swimming performance may be concealed by the effect of habitat.

p53 directly regulates αA- and ßA3/A1-crystallin genes to modulate lens differentiation.

It is well established that the tumor suppressor p53 plays major roles in regulating apoptosis and cell cycle progression. In addition, recent studies have demonstrated that p53 is actively involved in regulating cell differentiation in muscle, the circulatory system and various carcinoma tissues. We have recently shown that p53 also controls lens differentiation. Regarding the mechanism, we reveal that p53 directly regulates c-Maf and Prox1, two important transcription factors to control cell differentiation in the ocular lens. In the present study, we present further evidence to show that p53 can regulate lens differentiation by controlling expression of the differentiation genes coding for the lens crystallins. First, the αA and ßA3/A1 gene promoters or introns all contain putative p53 binding sites. Second, gel mobility shifting assays revealed that the p53 protein in nuclear extracts from lens epithelial cells directly binds to the p53 binding sites found in these crystallin gene promoters or introns. Third, exogenous wild type p53 induces dose-dependent expression of the luciferase reporter gene driven by different crystallin gene promoters and the exogenous dominant negative mutant p53 causes dose-dependent inhibition of the same crystallin genes. Fourth, ChIP assays revealed that p53 binds to crystallin gene promoters in vivo. Finally, in the p53 knockout mouse lenses, expression levels of various crystallins were found down-regulated in comparison with those from the wild type mouse lenses. Together, our results reveal that p53 directly regulates expression of different sets of genes to control lens differentiation.

PP-1α and PP-1γ display antagonism and differential roles in tumorigenicity of lung cancer cells.

Protein serine/threonine phosphatases are important cellular signaling molecules and play major roles in regulating many different functions including cell proliferation, senescence, programmed cell death, and oncogenic cell transformation. Among different serine/threonine phosphatases, PP-1 and PP-2A contribute to more than 90% phosphatase activities in eukaryotes. While the functions of PP-2A in cell transformation and tumorigenesis have been well established, the role of PP-1 in carcinogenesis remains to be further explored. Moreover, PP-1 exists in different isoforms, whether these isoforms have differential functions in tumorigenesis remains to be examined. In the present study, we demonstrated that in lung cancer 1299 cells, PP1α and PP- 1 & γ exist in an antagonizing balance. In the parent H1299 cells, PP-1γ is dominant, about 4-fold higher than that of PP-1α. Overexpression of PP-1α significantly down-regulates PP-1γ at both mRNA and protein levels. In contrast, knockdown of PP-1α leads to upregulation of PP-1γ. Moreover, overexpression of PP-1α significantly attenuates the ability of the H1299 cells in promoting tumorigenicity as tested in immuno-deficient nude mice. This attenuation is derived from the halted cell cycle progression, which is largely attributed by the changed RB-E2F activity. Together, our results demonstrate that PP-1α and PP-1γ not only antagonize each other in lung cancer cells, but also display differential functions in tumorigenicity.

Effect of ß-glucosidase on the meat quality and digestibility in broilers.

This study investigated the effects of supplementary ß-glucosidase on the carcass composition, meat quality, weight of digestive organ and apparent digestibility in male broilers. Two hundred and forty male, 1-day avine broiler chicks were randomly allocated into four treatment groups and fed with corn-soya bean meal supplemented with 0 (control), 0.6, 1.2 and 1.8 U/g of ß-glucosidase respectively. The results showed that there were no significant differences (p > 0.05) among groups in carcass composition (percentages of eviscerated yield, half-eviscerated yield, muscle yield of breast and leg). However, adding 0.6 U/g ß-glucosidase to the diet not only altered the meat quality by decreasing the drip loss ratio (p < 0.05) and relative lightness (L*) value (p < 0.01), increasing relative redness (a*) value (p < 0.01), but also significantly decreased the pancreas to body weight ratio (p < 0.05), however, with little effect on liver, proventriculus and gizzard to body weight ratio (p > 0.05). The length and width of duodenum villus were not affected by the addition of ß-glucosidase, but the coefficients of total tract apparent digestibility of protein and fat increased by 9.02% (p < 0.05) and 7.40% (p < 0.01) respectively; the parameters of ash were not affected by ß-glucosidase addition (p < 0.05). This study provided valuable information for evaluation of the effect of supplementary ß-glucosidase on the meat quality and digestibility of broilers.

Gill remodeling in crucian carp during sustained exercise and the effect on subsequent swimming performance.

Gill remodeling can be extensive in crucian carp, where up to a 7.5-fold increase in gill surface area has been observed during exposure to hypoxia through a reduction in the interlamellar cell mass (ILCM) and increased lamellar protrusion that has been hypothesized to be signaled by the need to maximize oxygen uptake under a given condition. Sustained aerobic exercise may have the greatest influence on oxygen demand in fish; however, its effect on gill remodeling in crucian carp has not been investigated. The specific objectives of this study were to determine (i) whether sustained aerobic exercise induces gill remodeling in the crucian carp, (ii) whether gill remodeling following sustained exercise affects the maximum critical swimming speed (U(crit)) and maximal oxygen consumption rate ([Formula: see text]), and (iii) whether gill remodeling following sustained exercise is associated with trade-offs related to ionoregulation. We measured [Formula: see text] in crucian carp at each step during an initial U(crit) test (U(crit1)), forced them to swim at 70% of U(crit) for 40 h, and then conducted a second U(crit) test (U(crit2)). From rest to U(crit1) (7-8 h), we observed a significant increase in protruding lamella height and area of the gills and a reduction in ILCM height and volume, likely associated with partial shedding of the ILCM, indicating that gill remodeling during exercise is rapid. Further changes were observed between U(crit1) and U(crit2), with statistically significant increases in protruding lamellar height, basal length and area, and a statistically significant reduction in protruding lamellar thickness and ILCM height and volume. Interestingly, there was no significant difference between U(crit1) and U(crit2) values, nor in maximal [Formula: see text] measured at U(crit1) and U(crit2). Furthermore, there was no significant difference in plasma osmolarity, [Na(+)], or [Cl(-)] in fish at rest, following U(crit1) or U(crit2). Thus, while these data support the hypothesis that the need to maximize oxygen uptake is an important signal for gill remodeling, which can occur quite rapidly (within 7 h at 15°C), the physiological implications of remodeling during exercise are less clear.

Effect of meal size on postprandial metabolic response in southern catfish (Silurus meridionalis).

Effect of relative meal size (0.6-24%) on specific dynamic action (SDA) was assessed in southern catfish juveniles (48.2+/-3.2 g) at 27.5 degrees C. Cutlets of freshly killed loach species were used as test diet. Energy expended during SDA was linearly correlated with relative meal size (r=0.949, p<0.001, N=47). There was no significant difference in SDA coefficient (energy expended on SDA quantified as a percentage of the energy content of the meal) among different relative meal size groups. Factorial metabolic scope increased from 1.47 to 4.08 when the relative meal size increased from 0.6% to 24%. The peak V O2 increased with meal size, but levelled when relative meal size gradually increased to the maximum. SDA duration showed a S-type (slow-fast-slow) increase course with increased meal size. The results of this study suggest that the high postprandial factorial metabolic scope and a trapezoid SDA curve might be the adaptation strategy of warm water sit-and-wait fish under the natural selection of evolution related to long-term food resources.

Nutritional homeostasis in carnivorous southern catfish (Silurus meridionalis): is there a mechanism for increased energy expenditure during carbohydrate overfeeding?

In previous growth experiments with carnivorous southern catfish (Silurus meridionalis), the non-fecal energy lose was positively related to dietary carbohydrate level. To test whether metabolic energy expenditure accounts for such energy loss, an experiment was performed with southern catfish juveniles (33.2-71.9 g) to study the effect of dietary carbohydrate level on fasting metabolic rate and specific dynamic action (SDA) at 27.5 degrees C. The fasting metabolic rate in this catfish was increased with dietary carbohydrate level, and the specific dynamic action (SDA) coefficient (energy expended on SDA as percent of assimilated energy) was not affected by dietary carbohydrate level. The results suggest that in southern catfish, carbohydrate overfeeding increases metabolic rate to oxidize unwanted assimilated carbohydrate. A discussion on the poor capacity of intermediate metabolism for adapting dietary carbohydrate in carnivorous fish and its possible relationship with facultative component of SDA was also documented in this paper.

Age estimation using a modified HPLC determination of ratio of aspartic acid in dentin.

Diastereomeric dipeptides were derived from the amino acid enantiomers in dentin by O-phthalaldehyde-N-acetyl-L-cysteine. The products were separated using high performance liquid chromatography (HPLC) and detected by fluorescence detector. A short analysis time (total analysis time was 15 min, including retention time, sample derivatization time and column regeneration time) was used. The sensitivity of detection was 1 pmol and high resolution (Rs = 1.5) was reached. We determined the D/L ratio of aspartic acid in dentin of 28 first premolars. The correlation value between the D/L ratio of aspartic acid and actual age was 0.9887; errors of +/- 1 year accounted for 46.4%, and no error exceeded 5 years.

Determination of trace iodine in food and biological samples by cathodic stripping voltammetry.

This paper describes a sensitive and selective method for the determination of iodine in food and biological samples. The method involves treatment of samples by combustion in an oxygen flask and determination of iodide by cathodic stripping voltammetry of the solid phase formed with the quaternary ammonium salt Zephiramine as the ionic associating agent; Br- is used as the complexing agent in the preconcentration process. We have studied the effect of concentration of Zephiramine, Br-, I-, and some other elements presented, deposition potential, preelectrolysis time, and scan rate, on the stripping curve shape and maximum stripping current. Determinations of trace iodine in table salt, laver, and eggs were demonstrated as practical examples.

[Retinal detachment associated with coloboma of choroid].

Retinal detachment associated with congenital coloboma of choroid is an unusual type of the disease 32 cases (34 eyes), or 1.23% of all 2,602 cases of retinal detachment, were operated on during 1980 to 1986. 17 (53%) patients were under 20 years of age and 28(88%) under 30 years. Preoperative visual acuities ranged from light perception to 0.2, and 25 eyes(74%) under 0.05. The associated congenital abnormalities were coloboma of iris in 32 eyes(94%), cataract in 25(74%), microcornea in 17(50%), and nystagmus in 13(38%). The detection of breaks in the rudimentary retina was extremely difficult, with a positive rate of only 56%, and immediate operative success was obtained in 18 eyes(53%), which were followed up for an average 36 months with re-detachment in 5 eyes. The rate of long term operative success was 38%. With the choroidal coloboma below the optic disc, the retinal breaks outside of the coloboma or in the coloboma near the edge, or the detachment involving at most 3 quadrants of the fundus, the rates of operative success were 81%, 70%, and 100% respectively.

Ischemic papillopathy and contraceptives.

PIP: In January and again in April 1985, a 30-year old woman received 150 mg injections of Depo-Provera for contraception. 3 days after the 2nd injection, she experienced blurred vision in both eyes and was diagnosed as having bilateral papilledema. Her vision improved after treatment with vitamin B1 and other drugs. But optic atrophy of the right eye and papilledema of the left eye remained. In July 1985, after an injection with Depo-Provera, her vision again worsened. The woman received no more Depo-Provera after this time. In early 1987, she was referred to Beijing's Tong Ren Hospital, where she was diagnosed as having bilateral ischemic papillopathy and optic atrophy. There have been few documented cases in medical literature of ocular complications related to use of contraceptives. In 1981, Petursson et al. reported a case of macula edema resulting from oral contraceptives. In animal studies, oral contraceptives have been linked to papilledema and retinal vein obstruction. The case reported here is the 1st to link use of Depo- Provera with ocular complications.^ieng