A novel tape spring hinge mechanism for quasi-static deployment of a satellite deployable using shape memory alloy

A tape spring hinge (TSH) is a typical flexible deployment device for a satellite and becomes frequently used due to its simplicity, lightweight, low cost, and high deployment reliability. However, the performance of a TSH is quite limited due to trade-offs among deployed stiffness, deployment torque, and latch-up shock despite its many advantages. In this study, a novel conceptual design that circumvents the trade-offs among functional requirements (FRs) is proposed. The trade-offs are obviated by a newly proposed shape memory alloy damper that converts the deployment behavior of a conventional TSH from unstable dynamic to stable quasi-static. This makes it possible to maximize the deployment stiffness and deployment torque of a conventional TSH, which are larger-the-better FR, without any increase in the latch-up shock. Therefore, in view of conceptual design, it is possible to design a highly improved TSH that has much higher deployed stiffness and deployment torque compared to a conventional TSH while minimizing latch-up shock and deployment unstableness. Detailed design was performed through response surface method and finite element analysis. Finally, a prototype was manufactured and tested in order to verify its performance (four point, deployment torque, and latch-up shock tests). The test results confirm the feasibility of the proposed TSH mechanism.

Biosorption of uranium(VI) from aqueous solution by biomass of brown algae Laminaria japonica

The uranium(VI) adsorption efficiency of non-living biomass of brown algae was evaluated in various adsorption experimental conditions. Several different sizes of biomass were prepared using pretreatment and surface-modification steps. The kinetics of uranium uptake were mainly dependent on the particle size of the prepared Laminaria japonica biosorbent. The optimal particle size, contact time, and injection amount for the stable operation of the wastewater treatment process were determined. Spectroscopic analyses showed that uranium was adsorbed in the porous inside structure of the biosorbent. The ionic diffusivity in the biomass was the dominant rate-limiting factor; therefore, the adsorption rate was significantly increased with decrease of particle size. From the results of comparative experiments using the biosorbents and other chemical adsorbents/precipitants, such as activated carbons, zeolites, and limes, it was demonstrated that the brown algae biosorbent could replace the conventional chemicals for uranium removal. As a post-treatment for the final solid waste reduction, the ignition treatment could significantly reduce the weight of waste biosorbents. In conclusion, the brown algae biosorbent is shown to be a favorable adsorbent for uranium(VI) removal from radioactive wastewater.

Malignant abdominal rocks: where do they come from?

For the radiologist, calcifications in an abdominal malignancy raise questions of both diagnostic and prognostic significance. Although certain cancers are well known to calcify, such as colorectal and ovarian, malignant abdominal calcifications actually arise from a wide variety of epithelial, mesenchymal, lymphoid, or germ cell neoplasms. The pathophysiology of calcification in abdominal malignancies is heterogeneous and incompletely understood. Calcifications may present primarily, in untreated tumors, or develop during treatment; the latter can occur in variable clinical settings. A basic understanding of the varied pathogenic etiology can assist the radiologist in assessing disease status. By presenting an assortment of calcified abdominal malignancies on computed tomography in varied clinical settings, we aim not only to inform the differential diagnosis, but also to clarify the prognosis of calcifications in abdominal malignancies.

Development of a Scale to Assess Immigrant Women's Needs for Pregnancy and Postpartum Adaptation

PURPOSE

The purpose of this study was to develop a scale to assess immigrant women's needs for pregnancy and postpartum adaptation and to test the reliability and validity of the scale.

METHODS

To construct scale items, critical issues and difficulties associated with pregnancy and postpartum adaptation of immigrant women were identified and categorized through a literature review. Fifty-two scale items were constructed, and data for validity and reliability testing was collected with a questionnaire survey from 367 immigrant women. Data were analyzed with descriptive statistics, factor analysis, and reliability coefficients.

RESULTS

The final measurement scale to assess immigrant women's pregnancy and postpartum adaptation consisted of 48 items and 7 factors (adaptation to daily activity during pregnancy, cross-cultural understanding and personal respect, understanding of the process of pregnancy and delivery, baby rearing and family support, physical and emotional adaptation after childbirth, nutrition during pregnancy, and sexual life adaptation). The seven factors accounted for 64.26% of the variance, and Cronbach's alpha was .96.

CONCLUSION

The scale developed by this study is a reliable and valid instrument and can be used to assess needs of pregnancy and postpartum adaptation and can be utilized in providing nursing interventions for immigrant women.

Association between cord blood 25-hydroxyvitamin D concentrations and respiratory tract infections in the first 6 months of age in a Korean population: a birth cohort study (COCOA)

PURPOSE

Previous studies suggest that the concentration of 25-hydroxyvitamin D [25(OH)D] in cord blood may show an inverse association with respiratory tract infections (RTI) during childhood. The aim of the present study was to examine the influence of 25(OH)D concentrations in cord blood on infant RTI in a Korean birth cohort.

METHODS

The levels of 25(OH)D in cord blood obtained from 525 Korean newborns in the prospective COhort for Childhood Origin of Asthma and allergic diseases were examined. The primary outcome variable of interest was the prevalence of RTI at 6-month follow-up, as diagnosed by pediatricians and pediatric allergy and pulmonology specialists. RTI included acute nasopharyngitis, rhinosinusitis, otitis media, croup, tracheobronchitis, bronchiolitis, and pneumonia.

RESULTS

The median concentration of 25(OH)D in cord blood was 32.0 nmol/L (interquartile range, 21.4 to 53.2). One hundred and eighty neonates (34.3%) showed 25(OH)D concentrations less than 25.0 nmol/L, 292 (55.6%) showed 25(OH)D concentrations of 25.0-74.9 nmol/L, and 53 (10.1%) showed concentrations of ≥75.0 nmol/L. Adjusting for the season of birth, multivitamin intake during pregnancy, and exposure to passive smoking during pregnancy, 25(OH)D concentrations showed an inverse association with the risk of acquiring acute nasopharyngitis by 6 months of age (P for trend=0.0004).

CONCLUSION

The results show that 89.9% of healthy newborns in Korea are born with vitamin D insufficiency or deficiency (55.6% and 34.3%, respectively). Cord blood vitamin D insufficiency or deficiency in healthy neonates is associated with an increased risk of acute nasopharyngitis by 6 months of age. More time spent outdoors and more intensified vitamin D supplementation for pregnant women may be needed to prevent the onset of acute nasopharyngitis in infants.

A case of eosinophilic fasciitis presenting as pitting edema of the lower extremities

Eosinophilic fasciitis is a rare disease characterized by diffuse fasciitis with peripheral eosinophilia and progressive induration and thickening of the skin and soft tissues. We report a 19-year-old female who presented with pitting edema in both lower extremities. She had a history of excessive physical activity before her symptoms developed. Physical examination revealed 2+ pitting edema in both lower legs. She complained of mild pain in both knee joints and feet, with no tenderness or heating sensations. Laboratory results were unremarkable except for severe eosinophilia. Parasite infection, venous thrombosis, and cardiac and renal problems were excluded. A magnetic resonance imaging study of both lower extremities revealed increased signal intensity in the subcutaneous lesions, consistent with superficial inflammation of the fascia. Mixed perivenular lymphoplasmacytic and eosinophilic infiltration in the subcutaneous lesion were observed on biopsy. The patient was treated with corticosteroids, resulting in remarkable improvement in both edema and eosinophilia.

Effect of cholesterol depletion on interleukin-8 production in human respiratory epithelial cells

PURPOSE

The lipid entities of cell membranes are components of the immune system and important mediators of inflammation. Despite increasing interest in the function of epithelial cells in inflammation, the role of cholesterol in this process has not been described. Here, we investigated the effect of cholesterol depletion on the inflammatory process in airway epithelial cells via the expression of interleukin (IL)-8 as a marker of inflammation.

METHODS

A 549 cells were treated with 0.5% methyl-β-cyclodextrin as a selective cholesterol extractor. The IL-8 level was assessed by enzyme-linked immunosorbent assay and reassessed after cholesterol repletion. Mitogen-activated protein kinase (MAPK) inhibitors were used to determine the upstream signaling pathway for IL-8 production in cholesterol-depleted cells.

RESULTS

We found a relationship between the amount of cholesterol in A 549 cells and inflammation of the airway. IL-8 production was increased in cholesterol-depleted A 549 cells and restored by cholesterol repletion. IL-8 production was decreased by pretreatment with the extracellular signal-regulated kinase (ERK) inhibitor U0126 but not with JNK inhibitor II or the p38 MAPK inhibitor SB202190.

CONCLUSIONS

Our findings suggest that inflammatory responses are increased in cholesterol-depleted epithelial cells via the MAPK signaling system, predominantly by the ERK pathway. We conclude that the lipid components of airwayepithelial cells may play a role in the inflammatory process.

Fractional exhaled nitric oxide and impulse oscillometry in children with allergic rhinitis

Purpose

Airway inflammation, bronchial hyper-responsiveness (BHR), and bronchodilator response (BDR) are representative characteristics of asthma. Because allergic rhinitis (AR) is a risk factor for asthma development, we evaluated these 3 characteristics in AR using measurement of fractional exhaled nitric oxide (FeNO), a methacholine challenge test (MCT), and impulse oscillometry (IOS).

Methods

This study included 112 children with asthma (asthma group), 196 children with AR (AR group), and 32 control subjects (control group). We compared pulmonary function parameters and FeNO levels among the 3 groups. The AR group was subdivided into 2 categories: the AR group with BHR and the AR group without, and again pulmonary function and FeNO levels were compared between the 2 subgroups.

Results

FeNO levels were more increased in the AR and asthma groups than in the control group; within the AR group, FeNO was higher in the AR group with BHR than in the AR group without. The BDR was more increased in the AR group than in the control group when percent changes in reactance at 5 Hz (Δ X5) and reactance area (Δ AX) were compared. In the AR group, however, there was no difference in Δ X5 and Δ AX between the AR group with BHR and the AR group without.

Conclusions

Reversible airway obstruction on IOS and elevated FeNO levels were observed in children with AR. Because elevated FeNO levels can indicate airway inflammation and because chronic inflammation may lead to BHR, FeNO levels may be associated with BHR in AR. IOS can be a useful tool for detecting lower airway involvement of AR independent of BHR assessed in the MCT.

Impact of liver fibrosis on prognosis following liver resection for hepatitis B-associated hepatocellular carcinoma

BACKGROUND

This study aims to evaluate the impact of liver fibrosis severity on prognosis following liver resection among HBV-HCC patients.

METHODS

Data were extracted from a prospective database of 189 HBV-HCC patients treated at Mount Sinai between 1995 and 2008. Fibrosis staging of each surgical resection specimen using the modified Ishak method was performed by a single liver pathologist.

RESULTS

A wide range of Ishak fibrosis stage was observed among this patient population, with 29% having established cirrhosis (Ishak stage 6). Ishak stage 6 was independently associated with poor overall and recurrence-free survival. In patients with Ishak stage 1-5, Ishak stage did not affect survival; rather, tumour size was associated with poor overall survival, and tumour size, histologic activity index and serum AFP>20 ng ml(-1) were associated with poor recurrence-free survival. In patients with Ishak stage 6, poorly differentiated histology and tumour size were associated with poor overall survival, and tumour size was associated with poor recurrence-free survival.

CONCLUSION

HBV-HCC develops with varying degrees of underlying liver fibrosis; however, progressive liver fibrosis does not affect the outcomes following resection until cirrhosis is reached. Established cirrhosis, as defined histologically by Ishak stage 6, is an independent predictor of poor overall and recurrence-free survival among these patients.

Effect of seasonal changes on the transition between subclinical hypothyroid and euthyroid status

CONTEXT

The widespread use of thyroid tests in asymptomatic individuals identifies many patients with transient subclinical hypothyroidism.

OBJECTIVE

Our objective was to determine the effect of seasonal change on serum TSH levels and the transition between subclinical hypothyroid and euthyroid status.

DESIGN, SETTING, AND SUBJECTS

This was a retrospective longitudinal study of 1751 subclinical hypothyroid and 28 096 euthyroid subjects aged over 18 years who underwent serial thyroid function tests at a health screening center between October 2003 and May 2011.

MAIN OUTCOME MEASURES

Age-adjusted geometric mean values of the TSH level by month were calculated using linear mixed models. Adjusted odds ratios of test season and multiple baseline clinical factors were determined using generalized estimating equations.

RESULTS

During a median 36 months of follow-up, 57.9% of subclinical hypothyroid subjects reverted to euthyroidism, and 4.3% of euthyroid subjects developed subclinical hypothyroidism. The monthly distribution of follow-up TSH levels indicated a biphasic pattern, ie, an increase during the winter-spring season and a decrease during the summer-fall season, with a maximal TSH difference of 0.69 mIU/L in subclinical hypothyroid and 0.30 mIU/L in euthyroid subjects. Normalization of subclinical hypothyroidism was increased 1.4-fold in follow-up tests during the summer-fall follow-up, whereas subclinical hypothyroidism increased 1.4-fold in euthyroid subjects during the winter-spring follow-up.

CONCLUSIONS

The season in which thyroid testing was performed was independently related to the transition between subclinical hypothyroid and euthyroid status. Seasonal variations in TSH concentration should be considered before deciding on treatment of subclinical hypothyroidism, particularly in the areas with a wide annual temperature range.

Changes in the clinicopathological characteristics and outcomes of thyroid cancer in Korea over the past four decades

BACKGROUND

Thyroid cancer has increased globally, with a prominent increase in small, papillary thyroid cancers (PTC). The Korean population has a high iodine intake, high prevalence of BRAF V600E mutations, and family histories of thyroid cancer. We examined the clinicopathological characteristics and outcomes of thyroid cancers in Korean patients over four decades.

METHODS

The medical records of 4500 thyroid cancer patients, between 1962 and 2009 at a single center, including 3147 PTC patients, were reviewed.

RESULTS

The mean age of the patients was 46.8±13.2 years; women accounted for 82.9% of the patients, and the median follow-up duration was 4.8 years (mean 7.0±5.8 years, range 1-43 years). The number of patients visiting the clinic increased from 411 during 1962-1990 to 2900 during 2000-2009. Age at diagnosis increased from 39.6±12.9 to 48.6±12.4 years. The male to female ratio increased from 1:6 to 1:4.5. The proportion of small (<1 cm) tumors increased from 6.1% to 43.1%, and the proportion of cancers with lymph node (LN) involvement or extrathyroidal extension (ETE) decreased from 76.4% to 44.4% and from 65.5% to 54.8% respectively. Although there were decreases in the proportion of LN involvement and ETE, these decreasing rates were not proportional to the expected rates based on the decreased proportion of large tumors. The overall recurrence and mortality rates were 13.3% and 1.4%. The five-year recurrence rate significantly decreased (from 11% to 5.9%), and the five-year mortality also improved (from 1.5% to 0.2%).

CONCLUSIONS

The incidence of thyroid cancer has rapidly increased, with a decrease in tumors of large size, LN involvement, and ETE, although the decreasing rates of LN involvement and ETE were not as prominent as decreasing rates of large size tumors. The mortality and recurrence rates have also decreased. Future long-term follow-up of patients diagnosed in the most recent decade is needed to confirm the prognostic characteristics of Korean PTC patients.

Avoidable causes of delayed enteral nutrition in critically ill children

To evaluate the incidence of delayed enteral nutrition (EN) and identify avoidable causes of delay, we retrospectively reviewed medical records of 200 children (median age [range]; 37.5 [1-216] months) who stayed in the intensive care unit (ICU) for a minimum of 3 days. Among 200 children, 115 received EN following ICU admission with a median time of EN initiation of 5 days after admission. Of these, only 22 patients achieved the estimated energy requirement. A significant decrease in the final z score of weight for age from the initial assessment was observed in the non-EN group only (-1.3±2.17 to -1.57±2.35, P<0.001). More survivors than non-survivors received EN during their ICU stay (61.2% vs 30.0%, P=0.001) and received EN within 72 hr of ICU admission (19.8% vs 3.3%, P=0.033). The most common reason for delayed EN was gastrointestinal (GI) bleeding, followed by altered GI motility and hemodynamic instability. Only eight cases of GI bleeding and one case of altered GI motility were diagnosed as active GI bleeding and ileus, respectively. This study showed that the strategies to reduce avoidable withholding EN are necessary to improve the nutrition status of critically ill children.

Anti-bacterial and anti-toxic immunity induced by a killed whole-cell-cholera toxin B subunit cholera vaccine is essential for protection against lethal bacterial infection in mouse pulmonary cholera model

The lack of appropriate animal model for studying protective immunity has limited vaccine development against cholera. Here, we demonstrate a pulmonary cholera model conferred by intranasal administration of mice with live Vibrio cholerae. The bacterial components, but not cholera toxin, caused lethal and acute pneumonia by inducing massive inflammation. Intranasal immunization with Dukoral, comprising killed whole bacteria and recombinant cholera toxin B subunit (rCTB), developed both mucosal and systemic antibody responses with protection against the lethal challenge. Either rCTB-free Dukoral or rCTB alone partially protected the mice against the challenge. However, reconstitution of rCTB-free Dukoral with rCTB restored full protection. Parenteral immunization with Dukoral evoked strong systemic immunity without induction of mucosal immunity or protection from the challenge. These results suggest that both anti-bacterial and anti-toxic immunity are required for protection against V. cholerae-induced pneumonia, and this animal model is useful for pre-clinical evaluation of candidate cholera vaccines.

Modulation of IL-8 boosted by Mycoplasma pneumoniae lysate in human airway epithelial cells

Mycoplasma pneumoniae, a major cause of community-acquired pneumonia, has been recognized as a trigger for asthma inception and exacerbation. The epithelial cells on the respiratory tract parasitized by M. pneumoniae exhibit a number of cytopathic effects as a result of local inflammation and stimulated host immune response. We investigated the interactions of signaling molecules regulating the release of IL-8 by the direct stimulation of M. pneumoniae lysate (MPL) in human airway epithelial cells. In human airway epithelial cells, MPL-induced IL-8 proteins were decreased by monoclonal anti-TLR2 antibody in a dose-dependent fashion, and significantly blocked by siRNA TLR2. The pharmacologic inhibitors of ERK, U0126 and PD98059, effectively reduced IL-8 expression and the active forms of ERK signaling molecules, as detected by anti-phosphorylated p44/42 antibody. The region spanning from -132 to +41 in the IL-8 promoter demonstrated the highest luciferase activity against MPL and the mutations of NF-κB and NF-IL6 entirely diminished the activity. After investigating transfections of the NF-κB and NF-IL6 reporter vectors, NF-IL6 activation was significantly induced by MPL stimulation, which was considerably decreased by U0126 and monoclonal anti-TLR2 antibody. These results indicate that MPL-induced IL-8 increase is transcriptionally regulated by NF-IL6 more than by NF-κB. Additionally, the activation of NF-IL6 is influenced by TLR2 and ERK signaling pathways in airway epithelial cells.

Temperature evolution of itinerant ferromagnetism in SrRuO3 probed by optical spectroscopy

The temperature (T) dependence of the optical conductivity spectra σ(ω) of a single crystal SrRuO(3) thin film is studied over a T range from 5 to 450 K. We observed significant T dependence of the spectral weights of the charge transfer and interband d-d transitions across the ferromagnetic Curie temperature (T(c) ∼ 150 K). Such T dependence was attributed to the increase in the Ru spin moment, which is consistent with the results of density functional theory calculations. T scans of σ(Ω,T) at fixed frequencies Ω reveal a clear T(2) dependence below T(c), demonstrating that the Stoner mechanism is involved in the evolution of the electronic structure. In addition, σ(Ω,T) continues to evolve at temperatures above T(c), indicating that the local spin moment persists in the paramagnetic state. This suggests that SrRuO(3) is an intriguing oxide system with itinerant ferromagnetism.

Inhalation toxicity of humidifier disinfectants as a risk factor of children's interstitial lung disease in Korea: a case-control study

BACKGROUND

The occurrence of numerous cases of interstitial lung disease in children (chILD) every spring in Korea starting in 2006 raised suspicion about a causal relationship with the use of humidifier disinfectants (HDs). The aim of this study was to evaluate the association between HD use and the risk of chILD.

METHODS

This retrospective, 1∶3 matched case-control study consisted of 16 cases of chILD that had developed between 2010 and 2011. The three groups of parallel controls (patients with acute lobar pneumonia, asthma, and healthy children) were matched by age, gender, and index date. Indoor/outdoor environmental risk factors, including HD use, were investigated by asking the guardians to complete a questionnaire.

RESULTS

The median age of the affected children (43.8% male) was 26 months (18.25-36.25). The chILD group did not differ significantly from the control groups with respect to socio-demographic and clinical variables. Indoor and outdoor environmental factors were not associated with a risk of chILD. However, the previous use of HDs (OR; 2.73. 95% CI; 1.41-5.90, P = 0.00) were independently associated with an increased risk.

CONCLUSIONS

This study showed that HDs, which are widely used in South Korea in the winter season, independently increased the risk of chILD in spring. Therefore, continuous monitoring and, if needed, changes in policy are essential to prevent and control pediatric diseases caused by toxic chemicals.