Rheological characteristics of injection molded titanium alloys powder

Ti-6Al-4V alloy powder was taken as raw material. 60%（mass fraction） paraffin, 35%low density polyethylene and 5%stearic acid were employed as binders to prepare injection feedstocks. Capillary rheometer was adopted to determine the rheological parameters and to analyze the rheological properties of the feedstocks at different milling time, powder loading and temperature. It is indicated through the results that the viscosity increases and the value of n decreases with the increase of milling time. The more the powder loading is, the higher the viscosity is. The empirical formula on the relationship between the viscosity and the powder loading is： ηr=η/ηb=A（1-Ф/Фmax）/^- m . The value m is calculated as 0.33. The flow activation energy Ea decreases with the increase of shear rate.

“喂”与“嚇”探源

汉语词义的发展可追溯到先秦的原始语言,词义最初形成时总是处于原始的混沌状态。"畏"最初为记录人们看到可怕事物时不由自主地发出的声音,后用来表示"害怕、恐惧"和"使害怕、恐惧"义,而"喂"为"畏"的分化字,后用以表示"打招呼"义。"嚇"最初可能也是人们驱除怪物时发出的恐吓怪物之声,本为象声词,既可象怒斥声,又有"大怒"义,还有"吓唬、恐吓而使害怕"义,引申又有"害怕"义。

Nutritional management of newborn infants:Practical guidelines

The requirements of growth and organ development create a challenge in nutritional management of newborn infants,especially premature newborn and intestinal-failure infants.Since their feeding may increase the risk of necrotizing enterocolitis,some high-risk infants receive a small volume of feeding or parenteral nutrition (PN) without enteral feeding.This review summarizes the current research progress in the nutritional management of newborn infants.Searches of MEDLINE (1998-2007),Cochrane Central Register of Controlled Trials (The Cochrane Library,Issue 3,2007),abstracts and conference proceedings,references from relevant publications in the English language were performed,showing that breast milk is the preferred source of nutrients for enteral feeding of newborn infants.The number of nutrients found in human milk was recommended as a guideline in establishing the minimum and maximum levels in infant formulas.The fear of necrotizing enterocolitis and feeding intolerance are the major factors limiting the use of the enteral route as the primary means of nourishing premature infants.PN may help to meet many of the nutritional needs of these infants,but has significant detrimental side effects.Trophic feedings (small volume of feeding given at the same rate for at least 5 d) during PN are a strategy to enhance the feeding tolerance and decrease the side effects of PN and the time to achieve full feeding.Human milk is a key component of any strategy for enteral nutrition of all infants.However,the amounts of calcium,phosphorus,zinc and other nutrients are inadequate to meet the needs of the very low birth weight (VLBW) infants during growth.Therefore,safe and effective means to fortify human milk are essential to the care of VLBW infants.

Low level of galacto-oligosaccharide in infant formula stimulates growth of intestinal Bifidobacteria and Lactobacilli

AIM: To investigate the effect of a new infant formula supplemented with a low level (0.24 g/100 mL) of galacto-oligosaccharide (GOS) on intestinal micro-flora (Bif idobacteria, Lactobacilli and E. coli) and fermentation characteristics in term infants, compared with human milk and a standard infant formula without GOS. METHODS: Term infants (n = 371) were approached in this study in three hospitals of China. All infants started breast-feeding. Those who changed to formula-feeding within 4 wk after birth were randomly assigned to one of the two formula groups. Growth and stool characteristics, and side effects that occurred in recruited infants were recorded in a 3-mo follow-up period. Fecal samples were collected from a subpopulation of recruited infants for analysis of intestinal bacteria (culture technique), acetic acid (gas chromatography) and pH (indicator strip). RESULTS: After 3 mo, the intestinal Bifidobacteria, Lactobacilli , acetic acid and stool frequency were significantly increased, and fecal pH was decreased in infants fed with the GOS-formula or human milk, compared with those fed with the formula withoutGOS. No significant differences were observed between the GOS formula and human milk groups. Supplementation with GOS did not influence the incidence of crying, regurgitation and vomiting. CONCLUSION: A low level of GOS (0.24 g/100 mL) in infant formula can improve stool frequency, decrease fecal pH, and stimulate intestinal Bifidobacteria and Lactobacilli as in those fed with human milk.

Immune response,stress resistance and bacterial challenge in juvenile rainbow trouts Oncorhynchus mykiss fed diets containing chitosan-oligosaccharides

Effects of dietary supplementation of chitosan-oligosaccharides （COS） on the growth performance, immune response, stress resistance, and disease resistance of juvenile rainbow trout Oncorhynchus mykiss were studied. Four experimental diets containing 0, 20, 40, or 60 mg/kg COS （COSO, COS20, COS40, and COS60, respectively） were fed to juvenile rainbow trout （initial weight = 5.2 ± 0.3 g） for 8 weeks. By the end of the feeding trial, representative groups of fish from each dietary treatment were challenged with stressor （30 see air exposure） and pathogen exposure （intraperitoneal injection with Aeromonas hydrophila ）. Results showed that supplementation of COS in diets did not affect production performance and body composition of rainbow trout. However, fish fed the COS40 diet demonstrated improved phagocytic activities, respiratory burst activities and decreased serum cortisol level. Additionally, survival following A. hydrophila challenge was significant higher among fish fed the COS-supplemented feeds, although there was no difference based on the level of supplementation. The present study suggests that COS can be used as an immuno-stimulant in rainbow trout feeds

Hepatitis B in pregnancy

Chronic hepatitis B virus (HBV) infection affects about 350 million individuals worldwide. Management of HBV infection in pregnancy is difficult because of several peculiar and somewhat controversial aspects. The aim of the present review is to provide a tool that may help physicians to correctly manage HBV infection in pregnancy. This review focuses on (1) the effect of pregnancy on HBV infection and of HBV infection on pregnancy; (2) the potential viral transmission from mother to newborn despite at-birth prophylaxis with immunoglobulin and vaccine; (3) possible prevention of mother-to-child transmission through antiviral drugs, the type of antiviral drug to use considering their efficacy and potential teratogenic effect, and the timing of their administration and discontinuation; and (4) the evidence for the use of elective caesarean section vs vaginal delivery and the possibility of breastfeeding.

Optimization of Stocking Density for the Sea Cucumber, Apostichopus japonicus Selenka, Under Feed-Supplement and Non-Feed-Supplement Regimes in Pond Culture

Optimal stocking densities were investigated for the sea cucumber Apostichopusjaponicus Selenka under feed-supplement and non-feed-supplement regimes in net enclosures for 333 d. Substantial weight loss occurred during the aestivation phase （AE）. Decreased growth rates were also observed during the winter phase （WT）. In contrast, sea cucumbers showed rapid growth during the spring （SP） and autumn （AU） phases. Feeding regimes considerably influenced the growtb performance, i.e., sea cucumbers grew faster under feed-supplement regime than under non-feed-supplement regime （P 〈 0.05）. The average survival rates of sea cucumbers under feed-supplement regime were higher than those under non-feed-supplement regime for both the autumn phase and spring phase, but the differences were only significant for the latter phase （P〈 0.05）. The fitted B-N curves showed that the optimal stocking densities, in terms of net production, were 22.3 ind. m^-2 for feed-supplement regime and 14.1 ind. m^-2 for non-feed-supplement regime.

Effects of Starving and Re-feeding Strategies on the Growth Performance and Physiological Characteristics of the Juvenile Tongue Sole(Cynoglossus semilaevis)

Starving and re-feeding trials were conducted to evaluate the effects of starvation duration and recovery times on the growth performance and physiological characteristics of juvenile tongue sole Cynoglossus semilaevis, which included growth, body composition, intestinal morphology and digestive enzymes activities. The fish starved for one(D1), two(D2) and four(D4) days, respectively, were recovered for three(R3, R6, R12), seven(R7, R14, R28) and eleven(R11, R22, R44) folds of starvation days while the control fish were fed constantly. The experiment was conducted for 96 days. The fish individuals in D1R11, D2R14 and D2R22 caught up in weight with the control, indicating that complete compensatory growth existed in these fish individuals. The highest body weight gain and total specific growth rates were observed in D2R22. Food intake increased significantly in most treatments in comparison with that of the control except for D1R7 and D2R22(P < 0.05). Food conversion efficiency and apparent digest coefficient in D2R22 were significantly promoted, being higher than that of the control(P < 0.05). The activities of trypsin and lipase were found to be closely related to the growth performance. The activities of liver and hindgut trypsin, also midgut and hindgut lipase in D2R22 were significantly higher than those of the control(P < 0.05). The fold height(HF) of foregut and midgut increased significantly in D2R22, and HF decreased significantly in D1R3, D2R6 and D4R12(P < 0.05). On our findings, we may conclude that the optimum starving and re-feeding strategy is starving for 2 days and re-feeding for 22 days. And in this starving and re-feeding strategy, the compensatory growth could be mostly attributed to the promotion of food conversion efficiency and digestibility coefficiency.

An exploration of the breastfeeding behaviors of women aftercesarean section: A qualitative study

Objectives:To explore the factors affecting breastfeeding behaviors in women after cesarean section.Methods:This is a qualitative study that used a phenomenological approach.This study used individual face-to-face interviews with 19 women who underwent a cesarean section in a Women and Children’s Hospital in China between July to September 2019.Information saturationwas used to determine sample size.Data were analyzed using a thematic content analysis method.Themes were developed based on the theory of planned behavior.Results:Thirteen(68.42%)had a planned cesarean section,and six(31.58%)cesarean sections were unplanned or emergent.Three major themes emerged:ambivalent attitude about breastfeeding,motivation to comply with the traditional cultural norms,and barriers and challenges.The motivating factors for breastfeeding after cesarean sections included perceived benefits of human milk,support from healthcare professionals,and responsibility for breastfeeding.The challenges for breastfeeding after cesarean sections included physical discomfort,knowledge and skills deficit of breastfeeding,lactation deficiency,and lack of knowledge and coping skills in managing their depressive mood after cesarean sections.There were a couple of neutral factors,such as the influences of family and peers.These factors could influence women either positively as facilitators or negatively as barriers.Conclusions:The findings can offer valuable information for healthcare professionals to help women breastfeed after cesarean sections.To promote women’s breastfeeding behaviors after cesarean sections,it is necessary to change women’s attitudes,belief systems,and the external environments and help them become more confident.

Effects of a theory of planned behavior-based intervention on breastfeeding behaviors after cesarean section:A randomized controlled trial

Objectives:To examine the efficacy of an intervention based on the theory of planned behavior(TPB)in improving breastfeeding behavior among women with cesarean sections(C-sections).Methods:This research was a randomized controlled trial.Women with planned elective C-sections were recruited to participate in a randomized controlled trial between June and September 2020.One hundred thirty-two women were divided randomly into the intervention(n=66)and control group(n=66)by systematic random sampling.In the intervention group,an intervention project was implemented after Keywords:Breastfeeding Cesarean section Intervention studies Theory of planned behavior the C-section to establish positive breastfeeding attitudes,cultivate supportive subjective norms,enhance perceived behavioral control,and strengthen breastfeeding intention to change behaviors.Those in the control group received routine pre-and post-delivery care.Exclusive breastfeeding rate and breast problem were collected at 5 days,2 weeks,and 1 month after C-section.The modified Breastfeeding Attrition Prediction Tool(BAPT)on the first day in the hospital,two weeks,and one month after C-section and Numerical Rating Scale(NRS)24 h postoperatively were used to compare the intervention effect between the two groups.Results:After the intervention,the intervention group had significantly higher exclusive breastfeeding rates than the control group at five days(86.4%vs.60.6%),two weeks(77.3%vs.57.6%),and one month(74.2%vs.50.0%)after the C-section.Besides,the intervention group was less likely to have sore nipples at five days(6.1%vs.18.2%in the control group,P<0.05)and two weeks(9.1%vs.12.1%in the control group,P<0.05).After two weeks of intervention,attitude scores(90.64±8.31 vs.87.20±8.15,P<0.05),subjective norm scores(88.07±24.65 vs.79.42±19.47,P<0.05)and behavior control scores in the intervention group were significantly higher than those in the control group.After one month of intervention,attitude scores(90.34±10.35 vs.84.22±10.51,P<0.05)and behavior control scores(43.13±5.02 vs.39.15±4.69,P<0.05)in the intervention group were significantly higher than those in the control group,which resulted in the higher breastfeeding intention in the intervention group.Conclusion:This study indicated that the TPB-based interventions effectively improved women's breastfeeding behaviors after C-sections.

Evaluation of a new method for placing nasojejunal feeding tubes

AIM:To compare fluoroscopic, endoscopic and guide wire assistance with ultraslim gastroscopy for placement of nasojejunal feeding tubes. METHODS:The information regarding nasojejunal tube placement procedures was retrieved using the gastrointestinal tract database at Tongji Hospital affiliated to Tongji Medical College. Records from 81 patients who underwent nasojejunal tubes placement by different techniques between 2004 and 2011 were reviewed for procedure success and tube-related outcomes. RESULTS:Nasojejunal feeding tubes were successfully placed in 78 (96.3%) of 81 patients. The success rate by fluoroscopy was 92% (23 of 25), by endoscopic technique 96.3% (26 of 27), and by guide wire assistance (whether via transnasal or transoral insertion)100% (23/23, 6/6). The average time for successful placement was 14.9 ± 2.9 min for fluoroscopic placement, 14.8 ± 4.9 min for endoscopic placement, 11.1 ± 2.2 min for guide wire assistance with transnasal gastroscopic placement, and 14.7 ± 1.2 min for transoral gastroscopic placement. Statistically, the duration for the third method was significantly different (P < 0.05) compared with the other three methods. Transnasal placement over a guidewire was significantly faster (P < 0.05) than any of the other approaches. CONCLUSION:Guide wire assistance with transnasal insertion of nasojejunal feeding tubes represents a safe, quick and effective method for providing enteral nutrition.

Can mean platelet volume play a role in evaluating the severity of acute pancreatitis?

AIM To investigate serum mean platelet volume(MPV) levels in acute pancreatitis(AP) patients and assess whether MPV effectively predicts the disease severity of AP.METHODS We included 117 consecutive patients with AP as the AP group and 34 consecutive patients with colorectal polyps(before endoscopic treatment) as the control group. Complete blood counts, liver function, platelet indices(MPV), coagulation parameters, lactate dehydrogenase(LDH) and C-reactive protein(CRP) were measured on days 1, 2, 3 and 7 after admission. Receiver operating characteristic curves were used to compare the sensitivity and specificity of MPV, white blood cell(WBC), LDH and CRP in predicting AP severity. The Modified Glasgow Prognostic Score(m GPS) and the 2012 revised Atlanta criteria were used to evaluate disease severity in AP.RESULTS MPV levels were significantly lower in the AP group than in the control group on day 1(P = 0.000), day 2(P = 0.029) and day 3(P = 0.001) after admission.In addition, MPV values were lower on day 1 after admission than on day 2(P = 0.012), day 3(P = 0.000) and day 7(P = 0.002) in all AP patients. Based on the m GPS, 78 patients(66.7%) were diagnosed with mild and 39 patients(33.3%) with severe AP. There was no significant difference in mean MPV levels between patients diagnosed with mild and severe AP based on the m GPS(P = 0.424). According to the 2012 revised Atlanta criteria, there were 98 patients(83.8%) without persistent organ failure(OF) [non-severe acute pancreatitis(non-SAP) group] and 19 patients(16.2%) with persistent OF(SAP group). MPV levels were significantly lower in the SAP group than in the non-SAP group on day 1 after admission(P = 0.002). On day 1 after admission using a cut-off value of 6.65 f L, the overall accuracy of MPV for predicting SAP according to the 2012 revised Atlanta criteria(AUC = 0.716) had a sensitivity of 91.8% and a specificity of 47.4% and was superior to the accuracy of the traditional markers WBC(AUC = 0.700) and LDH(AUC = 0.697).CONCLUSION MPV can be used at no additional cost as a useful, noninvasive biomarker that distinguishes AP with persistent OF from AP without persistent OF on day 1 of hospital admission.

Entrance Effect on Load Capacity of Orifice Compensated Aerostatic Bearing with Feeding Pocket

The current research of the aerostatic thrust bearing mainly focuses on the porous material bearing and inherent compensated air bearing, which aims at obtaining small physical dimension and large load capacity. Although porous material bearing appears larger load capacity, materials anisotropy itself and void content distortion caused in heat-treating, and machining processes add greater complexity to internal flow transfer process. Inherent compensated air bearing has the advantages of simple structure and good stability, but its load capacity and static stiffness is not worth somewhat. In this paper, based on hydrostatic lubrication theory, finite volume method is presented for taking entrance effects into account in computing pressure distribution, load capacity and mass flow rates of circular aerostatic thrust bearings. Technical analysis, numerical simulations and laboratory demonstration tests of influence of pocket diameter and pocket depth on loading capacity of aerostatic thrust bearing are carried out on simple orifice compensated air bearings with feeding pockets. The static parameters, such as air consumption and pressure distributions, are measured as a function of supply pressure and air gap height for several different orifices and pockets size. Entrance effects are described in term of typical throttling types, and the effect of pocket diameter and pocket depth on load capacity is systematically described respectively. The proposed research results uncover the causation of throttling action of the orifice compensated air bearing with feed pocket and further develop and improve the design theory of air bearing.

Effects on the population dynamics of Brachionus rubens(Rotifera)caused by mercury and cadmium administered through medium and algal food Chlorella vulgaris

Due to industrial activities,heavy metal concentrations in aquatic systems of Mexico,are on the rise.Zooplankton,particularly rotifers,being sensitive and common components of freshwater,are widely used in ecotoxicological tests for establishing water quality criteria.Depending on the route of exposure(i.e.via medium or algal food),the toxicity of heavy metals varies.In the present study we evaluated the effect of cadmium and mercury exposed through medium and via algal food for the rotifer B.rubens.For both the heavy metals,we exposed rotifers via medium containing Chlorella at 0.5×10^(6)cells/ml or fed daily on previously exposed(1,2 and 4 h)alga to the toxicants(using 5 times the value of LC_(50)for B.rubens).For cadmium toxicity through medium,we used 3 toxicant levels(0.1,0.2 and 0.4 mg/L)and for mercury,we used 0.005,0.010 and 0.015 mg/L.Based on the LC_(50),B.rubens was 24 times more sensitive to mercury(0.035±0.002 mg/L)than cadmium.At a concentration of 0.4 mg/L,cadmium through the medium caused increased lag phase of B.rubens.When grown on Chlorella exposed for different durations to cadmium,the rotifer density decreased with the increasing duration of algal exposure to the heavy metal.When mercury was used in the medium or via algal food,the trends in the population growth of B.rubens were similar to those for cadmium.An increase in heavy metal concentration in the medium resulted in a decrease of the rate of population increase per day(r).The r varied from 0.33(in control)to 0.02 d^(-1)(in heavy metal treatment)depending on the mode of exposure though medium or via algal food.

Trophic ecology of small yellow croaker (Larimichthys polyactis Bleeker): stable carbon and nitrogen isotope evidence

The trophic ecology of the small yellow croaker （Larimichthys polyactis） was studied using stable isotope analyses. Samples were collected from July to September 2009 and 34 individuals from eight sites were examined for stable carbon and nitrogen isotopes. Stable carbon isotope ratios （~3C） ranged from -20.67 to -15.43, while stable nitrogen isotope ratios （~SN） ranged 9.18-12.23. The relationship between fi^3C and ~SN suggested high resource partitioning in the sampling area. Significant differences in stable isotope values among the eight sampling sites may be linked to environmental diversities involving various physical processes （such as ocean current, wind and tide） and different carbon sources. Furthermore, the stable isotope ratios may also explain the ontogenetic variability in diet and feeding, because δ13C and δ15N varied significantly with increasing body size. The findings are consistent with other studies on diet analyses in small yellow croaker. It was also demonstrated that stable isotope analysis could be used to estimate the trophic characters of small yellow croaker in feeding patterns and migrating habits.

Dietary Leucine Requirement for Juvenile Large Yellow Croaker Pseudosciaena crocea (Richardson,1846)

Dietary leucine requirement for juvenile large yellow croaker, Pseudosciaena crocea Richardson 1846 (initial body weight 6.0 g±0.1 g) was determined using dose-response method.Six isonitogenous (crude protein 43%) and isoenergetic (19 kJ g-1) practical diets containing six levels of leucine (Diets 1-6) ranging from 1.23% to 4.80% (dry matter) were made at about 0.7% increment of leucine.Equal amino acid nitrogen was maintained by replacing leucine with glutamic acid.Triplicate groups of 60 individuals were fed to apparent satiation by hand twice daily (05:00 and 17:30).The water temperature was 26-32℃, salinity 26-30 and dissolved oxygen approximately 7 mg L-1 during the experimental period.Final weight (FW) of large yellow croaker initially increased with increasing level of dietary leucine but then decreased at further higher level of leucine.The highest FW was obtained in fish fed diet with 3.30% Leucine (Diet 4).FW of fish fed the diet with 4.80% Leucine (Diet 6) was significantly lower than those fed Diet 4.However, no significant differences were observed between the other dietary treatments.Feed efficiency (FE) and whole body composition were independent of dietary leucine contents (P>0.05).The results indicated that leucine was essential for growth of juvenile large yellow croaker.On the basis of FW, the optimum dietary leucine requirement for juvenile large yellow croaker was estimated to be 2.92% of dry matter (6.79% of dietary protein).

Influence of earth gravity on reaction engineering of tubular reactor for high concentration tungsten ion-exchange

The influence of gravity on the reaction engineering of tubular reactor is studied by analyzing the residence time distribution curves.The results show that upflow-feeding mode is more beneficial compared with downflow-feeding mode,since the flow pattern of the fluid in the reactor is closer to plug flow.The result of dynamic experiment conducted in ion-exchange of tungsten metallurgy is as good as that in reaction engineering of ion-exchange column.Whether downflow-feeding or upflow-feeding mode is adopted,breakthrough time decreases when solution concentration increases.Upflow-feeding mode has longer breakthrough time and greater improvement in adsorption capacity especially with high WO3 concentration in ion-exchange.

Modeling on a Modified Feeding Mode of Simulated Moving Bed for Improving Productivity

A new feeding mode for a simulated moving bed(SMB) is proposed.The outlet stream from zone II is collected at regular intervals.The concentration of the solution is increased by dissolving raw materials and then fed to zone III as the feed stream during the next collection interval.In this feeding mode,the concentration of the stream fed to zone III is identical to that of original feed,while in a conventional SMB,the feed is diluted by mix-ing with the outlet stream of zone II before feeding to zone III.The new feeding mode increases the inlet concentra-tion of zone III.A modeling investigation shows that higher inlet concentration of zone III increases the height of concentration band in SMB,improving the separation performance significantly.In comparison with the traditonal feeding mode,the new feeding mode increases the productivity by 23.52%and decreases the solvent consumption by 22.56%,so as to increase the raffinate and extract concentrations by 53.17%and 20.38%,respectively.The col-lection interval for the outlet stream from zone II has no effect on the separation performance after reaching the steady state,so that the collection interval can be increased to make the operation more convenient.

Diet and feeding ecology of invasive icefish Neosalanx taihuensis in Erhai Lake,a Chinese plateau mesoeutrophicated lake

A comprehensive study of the invasive icefish Neosalanx taihuensis feeding ecology in Erhai Lake was conducted from November 2009 to October 2010. Prey items in the guts of the icefish sampled varied significantly according to season. This finding suggests a relationship between fluctuations in available prey in the environment and selective feeding by icefish. N. taihuensis preferred large-sized zooplankton, such as Daphnia and calanoids. Additionally, the gut fullness values differed significantly （P〈0.001） among sampling times. To compare the values at different times, samples were taken over a 24 h period every 2 months for the entire year. The feeding activities of the fish were concentrated either in the morning （8：00） and/or at dusk （20：00）, except in September 2010. This finding can be explained primarily by the variation in optimum light intensity. Daily N. taihuensis zooplankton consumption varied significantly, both diurnally and among seasons. The daily consumption values ranged from 0.089 to 0.237 g （wet weight） per 100 g wet fish weight in temperatures between 11.50℃ and 24.68℃. This is the first report of diel feeding periodicity and daily food consumption of icefish in their invaded ecosystems.

Post-pyloric feeding

Postpyloric feeding is an important and promising alternative to parenteral nutrition. The indications for this kind of feeding are increasing and include a variety of clinical conditions, such as gastroparesis, acute pancreatitis, gastric outlet stenosis, hyperemesis (including gravida), recurrent aspiration, tracheoesophageal fistula and stenosis in gastroenterostomy. This review discusses the differences between pre- and postpyloric feeding, indications and contraindications, advantages and disadvantages, and provides an overview of the techniques of placement of various postpyloric devices.