Understanding social networking sites continuance

Purpose

The purpose of this paper is to develop a theoretical model to investigate the determinants of continuance intention toward social networking sites (SNSs) by integrating the perspectives of the uses and gratifications theory, perceived interactivity and network externalities.

Design/methodology/approach

Data collected from 255 Facebook users in Taiwan were used to test the proposed model. The partial least squares method was used to test the measurement model and the structural model.

Findings

The findings reveal that emotional gratifications and social gratifications are the key predictors of users’ continuance intention toward SNSs. Further, the results indicate that perceived network size, perceived complementarity, machine interactivity and person interactivity influence information gratifications significantly, while perceived complementarity, machine interactivity and person interactivity exert positive effects on emotional gratifications. Finally, the results show that machine interactivity and person interactivity impact social gratifications positively, whereas perceived network size and perceived complementarity affect machine interactivity and person interactivity significantly.

Originality/value

This study is one of the earliest research inquiries to examine the effects of various types of gratifications on continuance intention. It is also one of the earliest studies to identify the antecedents of gratifications from social factors and technological attributes simultaneously.

Puzzle of magnetic moments of Ni clusters revisited using quantum Monte Carlo method

The puzzle of the magnetic moments of small nickel clusters arises from the discrepancy between values predicted using density functional theory (DFT) and experimental measurements. Traditional DFT approaches underestimate the magnetic moments of nickel clusters. Two fundamental problems are associated with this puzzle, namely, calculating the exchange-correlation interaction accurately and determining the global minimum structures of the clusters. Theoretically, the two problems can be solved using quantum Monte Carlo (QMC) calculations and the ab initio random structure searching (AIRSS) method correspondingly. Therefore, we combined the fixed-moment AIRSS and QMC methods to investigate the magnetic properties of Ni_n (n = 5-9) clusters. The spin moments of the diffusion Monte Carlo (DMC) ground states are higher than those of the Perdew-Burke-Ernzerhof ground states and, in the case of Ni_8-9, two new ground-state structures have been discovered using the DMC calculations. The predicted results are closer to the experimental findings, unlike the results predicted in previous standard DFT studies.

Successful Management of New-Onset Diabetes Mellitus and Obesity With the Use of Laparoscopic Sleeve Gastrectomy After Kidney Transplantation-A Case Report

In kidney transplantation, obesity is associated with poorer graft survival and patient survival. Bariatric surgery may provide benefit for these patients, not only by inducing weight loss, but also via reduction of diabetes. We report a case of morbid obesity, poorly controlled new-onset diabetes mellitus, and gout after kidney transplantation that was treated with laparoscopic sleeve gastrectomy 3 years after kidney transplantation. After 1 year of follow-up, 76% excessive body weight loss was attained. No complications were noted. The operation also provided total remission of diabetes and gout as well as good graft survival. Based on our experience, laparoscopic sleeve gastrectomy may be a feasible treatment for obese patients after renal transplantation to help resolve obesity and control new-onset diabetes. However, the timing of operation and the long-term potential for graft and patient survivals with this operation require further study.

The effect of individual and neighborhood socioeconomic status on esophageal cancer survival in working-age patients in Taiwan

Esophageal cancer is the sixth leading cause of cancer mortality. More than 90% of patients with esophageal cancer in Taiwan have squamous cell carcinoma. Survival of such patients is related to socioeconomic status (SES). We studied the association between SES (individual and neighborhood) and the survival of working-age patients with esophageal cancer in Taiwan. A population-based study was conducted of 4097 patients diagnosed with esophageal cancer between 2002 and 2006. Each was traced for 5 years or until death. Individual SES was defined by enrollee job category. Neighborhood SES was based on household income and dichotomized into advantaged or disadvantaged. Multilevel logistic regression was used to compare the survival rates by SES group after adjustment for possible confounding and risk factors. Hospital and neighborhood SES were used as random effects in multilevel logistic regression. In patients younger than 65 years, 5-year overall survival rates were worst for those with low individual SES living in disadvantaged neighborhoods. After adjustment for patient characteristics, esophageal cancer patients with high individual SES had a 39% lower risk of mortality than those with low individual SES (odds ratio 0.61, 95% confidence interval 0.48-0.77). Patients living in disadvantaged areas with high individual SES were more likely to receive surgery than those with low SES (odds ratio 1.45, 95% confidence interval 1.11-1.89). Esophageal cancer patients with low individual SES have the worst 5-year survival, even with a universal healthcare system. Public health, education, and social welfare programs should address the inequality of esophageal cancer survival.

Developing a dermatological photodiagnosis system by optical image analyses and in vivo study

Dermatological photodynamic therapy (DPDT) involves using systematic photosensitizers in combination with light irradiation treatment to eliminate cancer cells. Therefore, a noninvasive fluorescence photodiagnosis system is critical in DPDT for diagnosing target tissues and demarcating the margin of normal tissues. This study proposes a 375-nm ring LED light module in fluorescence imaging for DPDT applications. Image reproducibility (I.R.) and image interference (I.I.) analysis were performed. The results showed that the I.R. value of this fluorescence diagnostic system was higher than 99.0%, and the I.I. from external light sources was lower than 3.0%. In addition, the result of an in vivo study showed that the Chlorin e6 red fluorescence and the scope of distribution of B16-F10 melanoma cells in a mouse ear's vein could be measured clearly using our device; however, the comparison studio with 395-nm LED lights could not focus or capture the red fluorescence effectively.

Correction: Adjusted Age-Adjusted Charlson Comorbidity Index Score as a Risk Measure of Perioperative Mortality before Cancer Surgery

[This corrects the article DOI: 10.1371/journal.pone.0148076.].

A quantitative structure-activity relationship approach for assessing toxicity of mixture of organic compounds

Four types of reactivity indices were employed to construct quantitative structure-activity relationships for the assessment of toxicity of organic chemical mixtures. Results of analysis indicated that the maximum positive charge of the hydrogen atom and the inverse of the apolar surface area are the most important descriptors for the toxicity of mixture of benzene and its derivatives to Vibrio fischeri. The toxicity of mixture of aromatic compounds to green alga Scenedesmus obliquus is mainly affected by the electron flow and electrostatic interactions. The electron-acceptance chemical potential and the maximum positive charge of the hydrogen atom are found to be the most important descriptors for the joint toxicity of aromatic compounds.

Palliative Chemotherapy Affects Aggressiveness of End-of-Life Care

INTRODUCTION

Although palliative chemotherapy during end-of-life care is used for relief of symptoms in patients with metastatic cancer, chemotherapy may lead to more aggressive end-of-life care and less use of hospice service. This is a population-based study of the association between palliative chemotherapy and aggressiveness of end-of-life care.

PATIENTS AND METHODS

Using the National Health Insurance Research Database of Taiwan, we identified 49,920 patients with metastatic cancer who underwent palliative chemotherapy from January 1, 2009, to December 31, 2011. Patients who received chemotherapy 2-6 months before death were included. Aggressiveness of end-of-life care was examined by previously reported indicators. Cardiopulmonary resuscitation and endotracheal tube intubation were included as indicators of aggressive end-of-life care. The association between palliative chemotherapy and hospice care was studied.

RESULTS

Palliative chemotherapy was associated with more aggressive treatment. After adjustment for patient age, sex, Charlson Comorbidity Index score, cancer group, primary physician's specialty, postdiagnosis survival, hospital characteristics, hospital caseload, urbanization, and geographic regions, more than one emergency room visit (p < .001), more than one intensive care unit admission (p < .001), and endotracheal intubation (p = .02) during end-of-life care were significantly more common in patients receiving palliative chemotherapy. Patients who did not receive palliative chemotherapy received more hospice care in the last 6 months of life (p < .001).

CONCLUSION

Although the decision to initiate palliative chemotherapy was made several months before death, this study showed that palliative chemotherapy was associated with more aggressive end-of-life care, including more emergency room visits and intensive care unit admissions, and endotracheal intubation. The patients who received palliative chemotherapy received less hospice service toward the end of life.

IMPLICATIONS FOR PRACTICE

Palliative chemotherapy is used for patients with incurable cancer toward the end of life (EOL). Aggressiveness of EOL care and hospice care are related to the quality of life of these patients. This study of data from the Taiwanese National Health Insurance Research Database found that palliative chemotherapy led to more aggressive EOL care and less hospice care. There is a need to provide patients with terminal cancer access to care information that best meets their needs, especially those patients who receive palliative chemotherapy.

Home-Based Hospice Care Reduces End-of-Life Expenditure in Taiwan: A Population-Based Study

Inpatient hospice care can reduce futile treatment and medical costs. However, the cost trimming effect of home-based hospice care in hospital has yet not been explored. This study evaluates the impact of home-based hospice care on end-of-life expenditure in hospitals with different spending intensity. This is a population-based retrospective study in Taiwan. Cancer decedents were identified in the National Health Insurance Research Database (NHIRD) from 2009 to 2011. They are categorized by hospital spending intensity. A hierarchical linear regression model with a random-intercept model was used to analyze the relationship between end-of-life expenditure (dependent variable) with and without home-based hospice, and both patient-level and hospital-level characteristics. A total of 78,613 cancer decedents were identified in the NHIRD from 2009 to 2011. Of these decedents, 17,638, 43,286, and 17,689 were categorized by hospital spending intensity as high, moderate, and low, respectively. Decedents with home-based hospice care were associated with US$2452 less in expenditure per patient compared with those without home-based hospice care. The majority of savings occurred in the last 3 months of life. These savings with home-based hospice care were consistent in hospitals with different levels of spending intensity. Home-based hospice reduced one-fifth expenditure at the end of life of cancer decedents treated in hospitals with different spending intensity.

The Association of Hematological Malignancy and End-of-Life Expenditure in Cancer Decedents: A Population-Based Study in an Asian Country

Within the overall National Health Insurance (NHI) budget in Taiwan, there has been a remarkable increase in expenditure for cancer patients. This study was designed to explore whether hematological malignancy is associated with higher end-of-life (EOL) medical expenditure in their last 6 months of life.We used data from the Taiwan NHI Research Database to do a retrospective cohort and population-based study. There were 42,754 cancer patients enrolled in order to study the determinants of medical expenditure for EOL care from 2009 to 2011.The mean medical expenditure for EOL care for cancer patients in the last 6 months of life was $12,965 ± 10,959 (mean ± standard deviation ) (all costs are given in US dollars). Patients with acute leukemia and lymphoma had an additional cost of $16,934 and $7840 than those with nonhematological malignancy (P < 0.001). Medical expenditures for cancer patients with a hematological malignancy and postdiagnosis survival of >6 months, between 6 and 12 months, and >12 months all showed that acute leukemia and lymphoma accounted for more medical expenditure than did others (P < 0.001). The primary physician's specialty between acute leukemia, lymphoma, and nonhematological malignancy patients had statistically difference.The medical expenditure of cancer patients in acute leukemia and lymphoma was more than nonhematological malignancy. Treatment strategies for acute leukemia should be studied further in order to save the health care budget.

The safety and adequacy of resection on hepatocellular carcinoma larger than 10 cm: A retrospective study over 10 years

BACKGROUND/PURPOSE

Current treatment options for HCC≥10 cm (huge HCC) are limited. Otherwise, the margin status is known as a prognostic factor. Our aim was to determine the safety, effectiveness, and risk factors for overall survival and disease-free survival for these patients.

METHODS

A total of 211 consecutive patients from 2000/08 to 2010/12 were enrolled. Characteristics of patients, tumors, and treatment were compared between the huge group (HCCs; ≥10 cm, n = 23; 11%) and those with smaller group (HCC; <10 cm n = 188; 89%). Disease-free survival (DFS), overall survival (OS), and risk factors were analyzed.

RESULTS

Median follow up was 37 months. Patients with huge HCC were more likely to be symptomatic, positive for preoperative portal vein thrombosis, longer surgical time, more blood loss and transfusions, and significantly shorter median OS and DFS. Both groups had similar postoperative mortality and morbidity rates. In the huge HCC, multivariate analysis identified two significant determinants of DFS (preoperative portal vein thrombosis on imaging and tumor-free margin less than 1 mm) and two significant determinants of OS (age over 80 and preoperative portal vein thrombosis). Even with positive margins, it still had no impact on OS. For DFS, 1 mm free margins appeared to be adequate.

CONCLUSION

Tumor-free margin is an independent risk factor for recurrence but has no impact on OS. Surgical margin >1 mm is adequate in patients with tumors ≥10 cm. Postoperative close follow up, especially of distant metastasis, and appropriate treatment of recurrence by a multidisciplinary approach may improve prognosis.

Understanding the roles of cultural differences and socio-economic status in social media continuance intention

Purpose

– Drawing upon the literature of Uses and Gratifications (U & G) Theory, the purpose of this paper is to propose that entertainment, information seeking, socialization, and self-presentation are the motivational factors affecting continuance intention of social media. This paper further investigates the moderating effects of cultural difference and socio-economic status on the link between these motivational factors and continuance intention.

Design/methodology/approach

– Data collected from the 493 active users of Facebook in five countries (Australia, Austria, Japan, Taiwan, and the USA) were used to test the proposed model. Partial least squares method was used to assess the relationships in the model and the subgroup analysis method was employed as well to examine the moderating roles of cultural difference and socio-economic status.

Findings

– Information seeking exerts stronger effect on continuance intention for users from individualistic cultures, while socialization, and self-presentation has stronger influence on continuance intention for users from collective cultures. Entertainment has stronger influence on continuance for high educated users, whereas self-presentation has stronger influence on continuance intention for users with lower level of education. Finally, the effect of entertainment, information seeking on continuance intention is stronger for users with higher level of income, while self-presentation has stronger influence on continuance intention for users with lower level of income.

Originality/value

– This study is one of first studies to extend the research context of U & G Theory from adoption of social media to continuance intention of social media. This study is also the first to investigate the moderating roles of cultural difference and socio-economic statuses in social media usage behavior simultaneously.

Age-adjusted Charlson comorbidity index scores as predictor of survival in colorectal cancer patients who underwent surgical resection and chemoradiation

We studied the effect of Age-Adjusted Comorbidity Index Score in colorectal cancer patients who underwent similarly aggressive treatment. Using the National Health Insurance Research Database of Taiwan, we identified 5643 patients with colorectal cancer who underwent surgical resection and chemoradiation from 2007 through 2011. We estimated survival according to Age-Adjusted Comorbidity Index Scores and 5-year survival using Cox proportional hazard regression analysis, adjusting for sex, oxaliplatin-based chemotherapy, socioeconomic status, geographic region, and hospital characteristics. In the cohort were 3230 patients with colonic cancer and 2413 patients with rectal cancer, who had undergone combined surgical resection and either neoadjuvant or adjuvant chemoradiation. After adjusting for patient characteristics (sex, oxaliplatin-based chemotherapy, socioeconomic status, geographic region, and hospital-characteristics), colonic cancer patients with age-adjusted Charlson (AAC) ≥ 6 had a 106% greater risk of death within 5 years (adjusted HR = 2.06; 95% CI, 1.66-2.56). In rectal cancer patients, patients with an AAC score of 4-5 had a 28% greater risk of death within 5 years (adjusted HR = 1.28; 95% CI, 1.02-1.61), and those with AAC ≥ 6 had a 47% greater risk (adjusted HR = 1.47; 95% CI, 1.15-1.90). Age and burden of comorbidities influence survival of patients with colonic or rectal cancer. Age-Adjusted Comorbidity Score remains an independent prognostic factor even after adjusting for the aggressiveness of treatment.

Effect of liver cirrhosis on metastasis in colorectal cancer patients: a nationwide population-based cohort study

OBJECTIVE

The aim of this study is to evaluate the liver metastasis risk among colorectal cancer patients with liver cirrhosis.

METHODS

This was a nationwide population-based cohort study of 2973 newly diagnosed colorectal cancer patients with liver cirrhosis and 11 892 age-sex matched controls enrolled in Taiwan between 2000 and 2010. The cumulative risk by Kaplan-Meier method, hazard ratio by the multivariate Cox proportional model and the incidence density were evaluated.

RESULTS

The median time interval from the colorectal cancer diagnosis to the liver metastasis event was 7.42 months for liver cirrhosis group and 7.67 months for non-liver cirrhosis group. The incidence density of liver metastasis was higher in the liver cirrhosis group (61.92/1000 person-years) than in the non-liver cirrhosis group (47.48/1000 person-years), with a significantly adjusted hazard ratio of 1.15 (95% CI = 1.04-1.28, P = 0.007). The 10-year cumulative risk of liver metastasis for the liver cirrhosis and the non-liver cirrhosis group was 27.1 and 23.6%, respectively (P = 0.006). For early cancer stage with locoregional disease patients receiving surgery alone without adjuvant anti-cancer treatments, patients with liver cirrhosis (10-year cumulative risk 23.9 vs. 15.7%, P < 0.001) or cirrhotic symptoms (10-year cumulative risk 25.6 vs. 16.6%, P = 0.009) both still had higher liver metastasis risk compared with their counterparts. For etiologies of liver cirrhosis, the 10-year cumulative risk for hepatitis B virus and hepatitis C virus, hepatitis B virus, hepatitis C virus, other causes and non-liver cirrhosis were 29.5, 28.9, 27.5, 26.7 and 23.4%, respectively, (P = 0.03).

CONCLUSIONS

Our study found that liver metastasis risk was underestimated and even higher in colorectal cancer patients with liver cirrhosis.

Delayed-Onset Chylous Ascites After a Living-Donor Liver Transplant: First Case Successfully Treated With Conservative Treatment?

Chylous ascites is a rare complication in liver transplant. Few cases have been reported to date. In most cases, chylous ascites is diagnosed within 1 month after surgery because of intraoperative injury of the hilar lymphatic system. Preoperative massive ascites and use of a LigaSure vessel sealing system for hilar dissection have been reported as risk factors. We report a case of chylous ascites after a living-donor liver transplant that was diagnosed after 6 months of uneventful follow-up. Sirolimus was added to cyclosporine early (2 wk after the operation) owing to poor renal function and it was found to be high (> 22 ng/mL) when the chylous ascites occurred. The patient was treated with total parenteral nutrition in combination with Sandostatin and rapid tapering of sirolimus after the failed initial conservative treatment. Residual abdominal fullness after meals and lymphedema of the legs disappeared 1 month after discontinuing sirolimus. This is the first case of delayed-onset chylous ascites after a liver transplant that was successfully treated conservatively.

Low socioeconomic status is associated with more aggressive end-of-life care for working-age terminal cancer patients

BACKGROUND

The relationship between low socioeconomic status (SES) and aggressiveness of end-of-life (EOL) care in cancer patients of working age (older than 18 years and younger than 65 years) is not clear. We assessed the association between aggressiveness of EOL care and differences in SES among working-age terminal cancer patients from Taiwan between 2009 and 2011.

METHODS

A total of 32,800 cancer deaths were identified from the Taiwan National Health Insurance Research Database. The indicators of aggressive EOL care (chemotherapy, more than one emergency room [ER] visit or hospital admission, more than 14 days of hospitalization, intensive care unit [ICU] admission, and death in an acute care hospital) in the last month of life were examined. The associations between SES and the indicators were explored.

RESULTS

Up to 81% of the cancer deaths presented at least one indicator of aggressive EOL care. Those who were aged 35-44 years and male, had low SES, had metastatic malignant disease, lived in urban areas, or were in hospitals with more abundant health care resources were more likely to receive aggressive EOL care. In multilevel logistic regression analyses, high-SES cancer deaths had less chemotherapy (p < .001), fewer ER visits (p < .001), fewer ICU admissions (p < .001), and lower rates of dying in acute hospitals (p < .001) compared with low-SES cancer deaths.

CONCLUSION

Working-age terminal cancer patients in Taiwan received aggressive EOL care. EOL cancer care was even more aggressive in those with low SES. Public health strategies should continue to focus on low-SES patients to provide them with better EOL cancer care.

The effect of inductively-coupled-plasma reactive ion etching power on the etching rate and the surface roughness of a sapphire substrate

In this study, patterned sapphire substrates are fabricated using nanosphere lithography (NSL) and inductively-coupled-plasma reactive ion etching (ICP-RIE). Polystyrene nanospheres of approximately 600 nm diameter are self-assembled on c-plane sapphire substrates by spin-coating. The diameter of the polystyrene nanospheres is modified to adjust the etching mask pitch cycle using oxygen plasma in the ICP-RIE system. A nickel thin film mask of 100 nm thickness is deposited by electron-beam evaporation on a substrate covered with treated nanospheres. The sapphire substrate is then etched in an inductively coupled plasma system using BCl3/Ar gas, to fabricate a structure with a periodic sub-micron hole array with different sidewall intervals. The DC bias voltage, the sapphire etching rate, the surface roughness, are studied as a function of the ICP and the RF power. Different sub-micron hole arrays with spacing cycles of 89 nm, 139 nm and 167 nm are successfully fabricated on the sapphire substrate, using suitable etching parameters.

Vascular invasion affects survival in early hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is an aggressive malignant tumor with a high mortality rate. The optimal therapeutic choice for early HCC is surgical resection. However, the rate of intrahepatic recurrence is high. The objective of this study was to evaluate the effect of various factors on the survival of patients with early HCC. Between January 1st, 2006 and December 31st, 2013, a total of 89 patients who underwent surgery for HCC were retrospectively enrolled. The analysis was conducted using the Student's t-test, Chi-square test, Kaplan-Meier method and Cox proportional hazard regression model to assess potential confounding and predictive variables. The 3-year overall survival (OS) rate was 71%. The 3-year OS rates in patients with and those without vascular invasion were 62.1 and 92.8%, respectively (P<0.003). Based on the multivariate analysis, postoperative pathological vascular invasion (hazard ratio = 4.96; 95% confidence interval: 1.55-15.9) remained an independent predictor of adverse long-term outcome. Furthermore, vascular invasion was significantly associated with intrahepatic metastasis. These data emphasize the need for effective adjuvant therapy in selected high-risk patients with early HCC. Further studies are required to determine the optimal approach to further improving the prognosis of early HCC.

Preoperative risk score predicting 90-day mortality after liver resection in a population-based study

The impact of important preexisting comorbidities, such as liver and renal disease, on the outcome of liver resection remains unclear. Identification of patients at risk of mortality will aid in improving preoperative preparations. The purpose of this study is to develop and validate a population-based score based on available preoperative and predictable parameters predicting 90-day mortality after liver resection using data from a hepatitis endemic country.We identified 13,159 patients who underwent liver resection between 2002 and 2006 in the Taiwan National Health Insurance Research Database. In a randomly selected half of the total patients, multivariate logistic regression analysis was used to develop a prediction score for estimating the risk of 90-day mortality by patient demographics, preoperative liver disease and comorbidities, indication for surgery, and procedure type. The score was validated with the remaining half of the patients.Overall 90-day mortality was 3.9%. Predictive characteristics included in the model were age, preexisting cirrhosis-related complications, ischemic heart disease, heart failure, cerebrovascular disease, renal disease, malignancy, and procedure type. Four risk groups were stratified by mortality scores of 1.1%, 2.2%, 7.7%, and 15%. Preexisting renal disease and cirrhosis-related complications were the strongest predictors. The score discriminated well in both the derivation and validation sets with c-statistics of 0.75 and 0.75, respectively.This population-based score could identify patients at risk of 90-day mortality before liver resection. Preexisting renal disease and cirrhosis-related complications had the strongest influence on mortality. This score enables preoperative risk stratification, decision-making, quality assessment, and counseling for individual patients.