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Developmental sevoflurane exposure leads to widespread neuronal cell death known as sevoflurane-induced neurotoxicity (SIN). Receptor-interacting protein kinase-3 (RIPK3) and mixed lineage kinase domain-like (MLKL)-driven necroptosis plays an important role in cell fate. Previous research has shown that inhibition of RIPK1 activity alone did not attenuate SIN. Since RIPK3/MLKL signaling could also be activated by Z-DNA/RNA binding protein 1 (ZBP1), the present study was designed to investigate whether ZBP1-mediated and RIPK3/MLKL-driven necroptosis is involved in SIN through in vitro and in vivo experiments. We found that sevoflurane priming triggers neuronal cell death and LDH release in a time-dependent manner. The expression levels of RIPK1, RIPK3, ZBP1 and membrane phosphorylated MLKL were also dramatically enhanced in SIN. Intriguingly, knockdown of RIPK3, but not RIPK1, abolished MLKL-mediated neuronal necroptosis in SIN. Additionally, inhibition of RIPK3-mediated necroptosis with GSK'872, rather than inhibition of apoptosis with zVAD, significantly ameliorated SIN. Further investigation showed that sevoflurane treatment causes mitochondrial DNA (mtDNA) release into the cytosol. Accordingly, ZBP1 senses cytosolic mtDNA and consequently activates RIPK3/MLKL signaling. This conclusion was reinforced by the evidence that knockdown of ZBP1 or depleting mtDNA with ethidium bromide remarkably improved SIN. Finally, the administration of the RIPK3 inhibitor GSK'872 relieved sevoflurane-induced spatial and emotional disorders without influence on locomotor activity. Altogether, these results illustrate that ZBP1 senses cytosolic mtDNA to induce RIPK3/MLKL-driven necroptosis in SIN. Elucidating the role of necroptosis in SIN will provide new insights into understanding the mechanism of anesthetic exposure in the developing brain.

The small molecule chemical compound cinobufotalin (CB) is reported to be a potential antitumour drug that increases cisplatin (DDP) sensitivity in nasopharyngeal carcinoma. In this study, we first found that CB decreased DDP resistance, migration and invasion in lung adenocarcinoma (LUAD). Mechanistic studies showed that CB induced ENKUR expression by suppressing PI3K/AKT signalling to downregulate c-Jun, a negative transcription factor of ENKUR. Furthermore, ENKUR was shown to function as a tumour suppressor by binding to β-catenin to decrease c-Jun expression, thus suppressing MYH9 transcription. Interestingly, MYH9 is a binding protein of ENKUR. The Enkurin domain of ENKUR binds to MYH9, and the Myosin_tail of MYH9 binds to ENKUR. Downregulation of MYH9 reduced the recruitment of the deubiquitinase USP7, leading to increased c-Myc ubiquitination and degradation, decreased c-Myc nuclear translocation, and inactivation of epithelial-mesenchymal transition (EMT) signalling, thus attenuating DDP resistance. Our data demonstrated that CB is a promising antitumour drug and may be a candidate chemotherapeutic drug for LUAD patients.

This study investigates an inventory model interfaced with finance, marketing, and operations in a supplier-retailer-customer chain by incorporating some relevant and essential facts. The demand pattern is a multiplicative form of the retailer's selling price and credit period. The retailer receives an upstream advance-cash-credit payment plan from the supplier while offering a downstream cash-credit payment to customers. From the retailer's perspective, offering a longer credit period to customers results in more sales volume but a higher default risk than a shorter one. The retailer's objective is to determine the optimal credit period, selling price, and replenishment time simultaneously to maximize total profit. We develop the model to fit in a general framework that includes various payment types (such as advance, cash, credit, advance-cash, advance-credit, and cash-credit) and numerous previous models as special cases. We derive explicit closed-form solutions to optimal selling price, credit period, and cycle time for five possible cases. We then establish several theoretical results and identify which case is optimal under certain conditions. The purpose of this study is to explore pricing, crediting, and lot-sizing strategies under various payment types – advance, cash, and credit. Finally, we use the analysis numerically to investigate the impact of different payment schemes on the retailer profitability.

Cyberbullying is a major problem among our school-age population. The growing number of studies suggests that cyberbullying can often cause serious academic, emotional, social, and safety issues for its peer victims. The purpose of current study is to examine the nature of respondents' experience of cyberbullying and determine independently the impact of social learning and internet ethics on cyberbullying behavior among college students in Taiwan. The preliminary analysis is of a survey data collected from 359 undergraduate students in south of Taiwan through convenient sampling. The results of this study provide support for the hypotheses and explore the effect of social learning and perception of internet ethics on cyberbullying behavior among college students. Finding suggests that college students with lower level of social learning and with higher level of internet ethics will have less cyberbullying behavior than those with higher social learning and lower internet ethics.

Many products deteriorate with time and have a maximum lifetime. An expiration date will be marked. And then the product will no longer be sold after the expiration date. Thereafter, the demand rat...

Cyberbullying is a major problem among our school-age population. The growing number of studies suggests that cyberbullying can often cause serious academic, emotional, social, and safety issues for its peer victims. The purpose of current study is to examine the nature of respondents' experience of cyberbullying and determine independently the impact of social learning and internet ethics on cyberbullying behavior among college students in Taiwan. The preliminary analysis is of a survey data collected from 359 undergraduate students in south of Taiwan through convenient sampling. The results of this study provide support for the hypotheses and explore the effect of social learning and perception of internet ethics on cyberbullying behavior among college students. Finding suggests that college students with lower level of social learning and with higher level of internet ethics will have less cyberbullying behavior than those with higher social learning and lower internet ethics.

In the traditional economic order quantity (EOQ) model, it is assumed that the demand rate is constant. Thereafter, many researchers developed inventory model with time-varying demand to reflect sales in different phases of product life cycle in the market. However, in practice, especially for fashionable and high-tech product, the demand rate during the growth stages of its life cycle increases significantly with linear or exponential in the growth stage and then gradually stabilizes, and remains near constant in the maturity stage. It can be taken a ramp-type demand rate into account. Furthermore, in today’s supply chain, a supplier usually offers a permissible delay in payment to retailers to encourage them to buy more products, and a retailer in turn provides a downstream trade-credit period to its customers. Therefore, this paper focus on 1) ramp-type demand rate and 2) the upstream and downstream trade credit financing linked to order quantity for retailer is considered. The objective is to find the optimal replenishment cycle and order quantity to keep the total relevant cost per unit time as minimum as possible. The study shows that in each case discussed, the optimal solution not only exists but also is unique. Numerical examples are provided to illustrate the proposed model. Finally, some relevant managerial insights based on the results are characterized.

Saponins, the primary phytochemicals contributing to the health properties of G. pentaphyllum were frequently studied. However, compounds responsible for its bioactivities were still poorly understood. The saponin-rich fraction (GPMS), 3- O-[2G-( E)-Coumaroyl-3G- O-β-d-glucosyl-3R- O-β-d-glucosylrutinoside] (KCGG), gypenoside XLVI and gypenoside L were obtained by purification of G. pentaphyllum. The compounds were examined and compared with GPMS for their inhibitory effects on LPS-induced nitric oxide (NO) production. GPMS and KCGG differed in their inhibitory capacities against pro-inflammatory cytokines secretion. GPMS exhibited strong inhibition on inducible nitric oxide synthase (iNOS) and interleukin-6 (IL-6) mRNA expression but weak inhibition on tumor necrosis factor-α (TNF-α) and interleukin-1β mRNA expression. KCGG was better at inhibiting iNOS, IL-6, TNF-α, and cyclooxygenase-2 (COX-2) mRNA expression. GPMS showed similar inhibitory potency on mitogen-activated protein kinase phosphorylation and nuclear factor-κB (NF-κB) activation, as evidenced by their regulatory effects on LPS-induced P65 phosphorylation, NF-κB nuclear translocation, IκBα phosphorylation and degradation, IκKα/β phosphorylation, c-Jun N-terminal kinase phosphorylation, P38 phosphorylation, and COX-2 expression. KCGG was more powerful in inhibiting the NF-κB pathway, suggesting that KCGG might be used in the management of inflammatory-associated diseases in which NF-κB played pivotal roles. Furthermore, KCGG might be mainly responsible for the predominant effects of GPMS.

Gynostemma pentaphyllum (Thunb.) Makino was traditionally used as antiatherogenic foods in China but ingredients responsible for the effects remained unexplored. Here, kaempferol 3-O-[2G-(E)-Coumaroyl-3G-O-β-D-glucosyl-3R-O-β-D-glucosylrutinoside] (KCGG), gypenoside XLVI (GPXLVI), gypenoside LI (GPLI), gypenoside L (GPL), ginsenoside Rd (GSRd) and 2α, 3β, 12β, 20 (S)-tetrahydroxy-25-hydroperoxy-dammar-23-ene-20-O-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranoside (GLUP) were isolated, among which KCGG, GPLI and GLUP exhibited greater antioxidant potential. The predominant inhibitory effects of KCGG, GPLI and GLUP on oxidized low-density lipoproteins (ox-LDL)-induced foam cell formation and intracellular lipid accumulation were further confirmed at non-cytotoxic concentrations. KCGG mainly decreased interleukin-6 (IL-6) production, while GPLI and GLUP were more powerful in inhibiting interleukin-1β (IL-1β) accumulation. KCGG, GPLI and GLUP significantly inhibited extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) phosphorylation. They also dramatically promoted cholesterol efflux through up-regulating scavenger receptor class B type I (SRB1) expression. In conclusion, KCGG, GPLI and GLUP acted through different pathways that acted simultaneously.

Clinical ladder (CL)-3 nurses should have both an ability to integrate the clinical information of critically ill patients and to carry out the administrative work of the intensive care unit. However, in our unit, only 15.3% of nurses hold CL-3 certification, which is much lower than the hospital average of 23.1%. Thus, we initiated a project to raise this percentage in our unit. An analysis in January 2016 showed that the main obstacles to obtaining CL-3 certification in our unit were inability to write case reports, inadequate in-service education, and a lack of certified educators.The purpose of this project was to increase the number of CL-3-certified nurses in our intensive care unit.The resolution included holding courses on case report writing, briefings, and oral presentation techniques; assigning a preceptor to make nursing staff assignments; encouraging nurses to participate in the clinical nursing preceptor education training camp; and conducting practice tests using a multiple assessment tool.After implementation of this project, the percentage of unit nurses who had passed CL-3 increased to 39.0%.This project not only allowed our fellow nurses to share in the joy of clinical ladder advancement but also improved the atmosphere in the unit by encouraging self-development. This project helped stimulate professional growth among our staff and improved the quality of clinical care.提升某內科加護病房護理人員N3能力進階比率.N3護理人員具備重症整合性之照護能力，堪能勝任加護病房護理業務，但是本院某加護病房N3以上能力進階僅佔15.3%，低於全院N3以上能力進階比率23.1%，故引發專案動機。2016年1月經現況分析原因，包括：個案報告寫作能力不足、在職教育主講能力不足、未取得教師認證。.本專案目的在提升某內科加護病房護理人員N3能力進階比率。.安排個案報告寫作訓練、安排指導員輔導、教導簡報製作技巧、演練口頭報告、安排參加教師訓練營、演練使用多元化評估工具。.專案推動後單位N3能力進階比率提升至39.0%。.同儕間互相分享能力進階順利晉級的喜悅，亦鼓舞單位各層級的能力進階風氣，且提升護理專業成長與助益臨床照護品質。.

Objectives We aimed to analyze the effects of multidomain attention training on alertness, sustained attention, and visual-spatial attention in older adults with mild cognitive impairment (MCI). Design The design used in this study was a two-arm, parallel group, double-blind randomized controlled trial. Setting and participants The participants of the study were seventy-eight older adults with MCI (mean age: 79.5 ± 7.9 years) from retirement centers and community housing for the elderly. Intervention The participants were randomly assigned to an experimental group (multidomain attention training, n = 39) or an active control group (n = 39). Both groups underwent training sessions for 45 minutes three times per week for 6 weeks (18 sessions in total). Measures The main efficacy indicator was alertness (Trail Making Test Part B), sustained attention (Digit Vigilance Test), and visual-spatial attention (Trail Making Test Part A). The secondary outcome indicators were other cognitive functions (Mini-Mental State Examination [MMSE] and Montreal Cognitive Assessment [MoCA] subscales). Measurements were obtained at pretest, posttest, and 3 and 6 months after training. Results The results were analyzed by a generalized estimating equation (GEE), which indicated that attention outcomes (alertness, sustained attention, and visual-spatial attention) of the experimental group did not improve after training. However, the experimental group displayed a significant improvement in the attention, memory, and orientation of MMSE and MoCA subscales over a period of 6 months and also showed superior results compared with the control group. Conclusions Multidomain attention training demonstrated improved alertness and visual-spatial attention for posttest after 6 months. We also outline potential future advances in attention training for improving attention in older adults with MCI.

Objectives To examine the immediate and long-term effects of executive attention training on selective attention, focused attention, and divided attention in older adults with mild cognitive impairment. Methods A double-blind, multisite randomized controlled trial at five sites. Seventy participants (mean age: 78.19 ± 7.22 years) were assigned to an experimental group (executive attention training, n = 35) or an active control group (n = 35). The training duration was the same for both groups (45 minutes per session, 3 times per week, 18 sessions in total). Primary outcome measure was selective attention (Digit Span Task). Secondary outcome measures included focused attention (Stroop Color Word Test) and divided attention (Trail-Making Test Part B). Data were collected at pretest, post-test, 3-month follow-up, and 6-month follow-up. Results In GEE analysis, findings indicated a significant improvement in selective attention at post-test, whereas divided attention showed significant reducing omission error at 3-month follow-up. There was no significant effect of group in focused attention associated with the executive attention training compared with active control group. Conclusion The executive attention training significantly improved selective attention and divided attention performance. Future studies should identify transfer effects of attention training, and that can employ early screening to provide integrated attention training, and decrease its relevant risks on competency in performing daily activities, such as falling and driving.

This study investigated the online flow frequency among college students in regard to different internet activities, and analyzed the effect of flow frequency on internet addiction. This study surveyed 525 undergraduate internet users in Taiwan by using convenience sampling to question participants. In this paper, analysis of variance (ANOVA) was performed to examine the differences in usage activity regarding the level of flow frequency. To test the effects of the flow frequency factor on perceived internet addiction, multiple regression analysis was performed for the constructs of internet addiction from different internet usage activities. The analytical results indicate that online gaming by undergraduates in Taiwan reporting higher level of flow frequency than their primary internet activities and their flow frequency of online gaming will predict internet addiction.

Aims and objectives The purpose of this study was to investigate the effects of a music intervention on hospitalised psychiatric patients with different levels of anxiety. Background In clinical practice, psychiatric inpatients and nurses routinely suffer from anxiety. A music intervention may possibly be useful, but knowledge as to how useful and how effective it is in patients with different levels of anxiety is limited. Design The study design was a three-group, repeated-measures experimental study. Methods Subjects were 22 psychiatric patients who were divided into three groups based on their level of anxiety. They listened to 20 minutes of music each day for 10 days and were assessed using the Beck Anxiety Inventory before and after the music intervention and at a one-week follow-up; an electroencephalogram and finger temperature were monitored before and during the music intervention. Results Anxiety levels of all three groups showed a significant difference (p = 0·0339) after the intervention. The difference alpha and beta electroencephalogram percentages for all three groups showed a significant difference (p = 0·04; p = 0·01). The finger temperature showed a non-significant difference (p = 0·41). Conclusions A music intervention can effectively alleviate the anxiety of hospitalised psychiatric patients who suffer from all levels of anxiety. Relevance to clinical practice The study recommends a practice in alleviating anxiety. Effective lower-cost interventions to reduce anxiety in psychiatric inpatient settings would be of interest to nurses and benefit patients.

BACKGROUND memory training is a potential intervention for retaining memory and reducing dementia risk in older adults with mild cognitive impairment (MCI). OBJECTIVE this study examined the effect of virtual interactive working memory training (VIMT) in older adults with MCI. DESIGN single-blind, two-arm parallel-group, randomised controlled design. SETTING retirement homes, institutions, and communities. SUBJECTS a total of 66 older adults with MCI were recruited (mean age: 78.5 ± 7.6 years). METHODS participants were randomly assigned to the experimental group (VIMT, n = 33) or active control group (n = 33). The VIMT program used the CogniPlus (includes four training modules). Both groups attended 45 min sessions 3 times per week, a total of 36 sessions. The primary outcome was working memory; secondary outcomes were immediate memory, delayed memory, subjective memory complaints and global cognitive function. All variables were measured at pre-test, post-test, and 3-month follow-up. RESULTS between group, the effect of working memory adjusted mean difference by 1.75 (95% CI: 0.56 to 2.94; P < 0.01) at post-test. The results were analysed by a generalised estimating equation, which indicated that VIMT group significantly improved working memory at post-test (P = 0.01) relative to the active control group. CONCLUSIONS the applied VIMT program can enable older adults with MCI to maintain their working memory and reduce the rate of cognitive deterioration. TRIAL REGISTRATION This trial was registered on ClinicalTrials.gov (no.: NCT02462135).

In this paper, the monthly average of NCEP(National Center for Environmental Prediction)reanalysis data (2.5°×2.5°),the sounding data, and conventional observation data in Beijing (54511 station) were used to analyze the atmospheric pollution diffusion conditions in Beijing in recent 35 years. The main conclusions were:in 1980~2015, the whole layer was warmer. After 1990, the temperature inversion phenomenon was obvious, and the whole air was stable. The cold air's less effect on the lower layer, lower frequency of great north wind speed and surface layer's convergence led to the rising of pollution concentration. The location of sink motion at the high level was lower and that of the ascending motion at the low level was higher. This led to the constriction of the ascending motion below the boundary layer, worsening the pollution diffusion condition. In 1980~1989, the atmospheric capacity index was steady, while in 1990-1999,it fluctuated obviously and after 2000,it declined. In general, the atmospheric capacity presented a gentle decline. In spring and winter of 1980-1989, as well as spring and summer of 1990-2015, the atmospheric capacity was better. After 2000, the atmospheric capacity was decreasing compared to the last 20 years no matter in which season, and the difference of atmospheric capacity in seasons diminished. The boundary layer was higher in spring and summer, and lower in fall and winter in recent 35 years.

This paper is to propose a new concept, which is called the Multiple Equal Part Linear Regression, in which the analysis data are divided into several equal parts and then the linear regression model is built up. This way, we will be able to observe the trend of sample data in each equal part. Difference comparison can be made with the general standard linear regression model.

Aims and objectives The purpose of this study was to translate the Rowland Universal Dementia Assessment Scale into Chinese and to evaluate the psychometric properties (reliability and validity) and the diagnostic properties (sensitivity, specificity and predictive values) of the Chinese version of the Rowland Universal Dementia Assessment Scale. Background The accurate detection of early dementia requires screening tools with favourable cross-cultural linguistic and appropriate sensitivity, specificity, and predictive values, particularly for Chinese-speaking populations. Design This was a cross-sectional, descriptive study. Methods Overall, 130 participants suspected to have cognitive impairment were enrolled in the study. A test-retest for determining reliability was scheduled four weeks after the initial test. Content validity was determined by five experts, whereas construct validity was established by using contrasted group technique. The participants' clinical diagnoses were used as the standard in calculating the sensitivity, specificity, positive predictive value and negative predictive value. Results The study revealed that the Chinese version of the Rowland Universal Dementia Assessment Scale exhibited a test-retest reliability of 0·90, an internal consistency reliability of 0·71, an inter-rater reliability (kappa value) of 0·88 and a content validity index of 0·97. Both the patients and healthy contrast group exhibited significant differences in their cognitive ability. The optimal cut-off points for the Chinese version of the Rowland Universal Dementia Assessment Scale in the test for mild cognitive impairment and dementia were 24 and 22, respectively; moreover, for these two conditions, the sensitivities of the scale were 0·79 and 0·76, the specificities were 0·91 and 0·81, the areas under the curve were 0·85 and 0·78, the positive predictive values were 0·99 and 0·83 and the negative predictive values were 0·96 and 0·91 respectively. Conclusion The Chinese version of the Rowland Universal Dementia Assessment Scale exhibited sound reliability, validity, sensitivity, specificity and predictive values. Relevance to clinical practice This scale can help clinical staff members to quickly and accurately diagnose cognitive impairment and provide appropriate treatment as early as possible.

TRIM25, a member of the tripartite motif-containing (TRIM) family of proteins, plays an important role in cell proliferation, protein modification, and the RIG-I-mediated antiviral signaling pathway. However, relatively few studies have investigated the molecular characterization, tissue distribution, and potential function of TRIM25 in chickens. In this study, we cloned the full-length cDNA of chicken TRIM25 that is composed of 2706 bp. Sequence analyses revealed that TRIM25 contains a 1902-bp open-reading frame that probably encodes a 633-amino acid protein. Multiple comparisons with deduced amino acid sequences revealed that the RING finger and B30.2 domains of chicken TRIM25 share a high sequence similarity with human and murine TRIM25, indicating that these domains are critical for the function of chicken TRIM25. qPCR assays revealed that TRIM25 is highly expressed in the spleen, thymus and lungs in chickens. Furthermore, we observed that TRIM25 expression was significantly upregulated both in vitro and in vivo following infection with Newcastle disease virus. TRIM25 expression was also significantly upregulated in chicken embryo fibroblasts upon stimulation with poly(I:C) or poly(dA:dT). Taken together, these findings suggest that TRIM25 plays an important role in antiviral signaling pathways in chickens.

Background From the perspective of disease prevention, the enhancement of cognitive function among the healthy older people has become an important issue in many countries lately. This study aim to investigate the effect of cognitive-based training on the overall cognitive function, memory, attention, executive function, and visual-spatial ability of the healthy older people. Methods Cochrane, PubMed, EMBASE, MEDLINE, PsycINFO, and CINAHL of selected randomized controlled trials (RCTs), and previous systematic reviews were searched for eligible studies. The population focused on this study were healthy older people who participated in randomized controlled trials that investigated the effectiveness of cognitive-based training. The outcomes including change in overall cognitive function, memory, attention, executive function, and visual-spatial ability. Results We collected a total of 31 RCTs, the results showed that cognitive-based training has a moderate effect on overall cognitive function (g = 0.419; 95%CI = 0.205–0.634) and executive function (g = 0.420; 95%CI = 0.239–0.602), and a small effect on the memory (g = 0.354; 95%CI = 0.244–0.465), attention (g = 0.218; 95%CI = 0.125–0.311), and visual-spatial ability (g = 0.183;95%CI = 0.015–0.352) in healthy older people. Subgroup analysis indicated the intervention characteristics of ≧3 times each week (p = 0.042), ≧8 total training weeks (p = 0.003) and ≧24 total training sessions (p = 0.040) yields a greater effect size. Conclusions Cognitive-based training is effective for the healthy older people. This improvement can represent a clinically important benefit, provide information about the use of cognitive-based training in healthy older people, and help the healthy older people obtain the greatest possible benefit in health promotion and disease prevention.

A better understanding of people with cognitive disorders improves performance on memory tasks through memory-focused interventions are needed.The purpose of this study was to assess the effect of memoryfocused interventions on cognitive disorders through a meta-analysis.Systematic review and meta-analysis.The online electronic databases PubMed, the Cochrane Library, Ovid-Medline, CINHAL, PsycINFO, Ageline, and Embase (up to May 2017) were used in this study. No language restriction was applied to the search.Objective memory (learning and memory function, immediate recall, delayed recall, and recognition) was the primary indicator and subjective memory performance, global cognitive function, and depression were the secondary indicators. The Hedges' g of change, subgroup analyses, and meta-regression were analyzed on the basis of the characteristics of people with cognitive disorders.A total of 27 studies (2177 participants, mean age=75.80) reporting RCTs were included in the meta-analysis. The results indicated a medium-to-large effect of memory-focused interventions on learning and memory function (Hedges' g=0.62) and subjective memory performance (Hedges' g=0.67), a small-to-medium effect on delayed recall and depression, and a small effect on immediate recall and global cognitive function (all p0.05) compared with the control. Subgroup analysis and meta-regression indicated that the effects on learning and memory function were more profound in the format of memory training, individual training, shorter treatment duration, and more than eight treatment sessions, and the effect size indicated the MMSE score was the most crucial indicator (β=-0.06, p=0.04).This is first comprehensive meta-analysis of special memory domains in people with cognitive disorders. The results revealed that memory-focused interventions effectively improved memory-related performance in people with cognitive disorders. An appropriately designed intervention can effectively improve memory function, reduce disability progression, and improve mood state in people with cognitive disorders. Additional randomized controlled trials including measures of recognition, global cognitive function, and depression should be conducted and analyzed.

During the growth stage of a product life cycle especially for high-tech products, the demand function increases with time. In this paper, we extend the constant demand to a linear non-decreasing demand function of time and incorporate a permissible delay in payment under two levels of trade credit into the model. The supplier offers a permissible delay linked to order quantity, and the retailer also provides a downstream trade credit period to its customers. The objective is to find the optimal replenishment cycle that minimizes the retailer’s annual total relevant cost per unit time. The condition for an optimal solution to the generalized model is presented and some fundamental theoretical results are established. Finally, numerical examples to illustrate the proposed model are provided. Sensitivity analysis is performed and some relevant managerial insights are obtained.

In the business transactions, the supplier usually offers a permissible delay in payment to his retailer to attract more sales. In addition, a permissible delay in payment may be applied as an alternative to price discount. Based on the above phenomena, we incorporate a permissible delay in payment into the model of Yang [1] and develop a two-warehouse partial backlogging inventory model for deteriorating items with permissible delay in payment under inflation. The objective of this study is to derive the retailer’s optimal replenishment policy that maximizes the net present value of the profit per unit time. The necessary and sufficient conditions for an optimal solution are characterized. An algorithm is developed to find the optimal solution. Finally, numerical examples are provided to illustrate the proposed model. Sensitivity analysis is made and some managerial implications are presented.

In this study, quartz sand coated with water-treatment residuals was tested for its effectiveness as an arsenic adsorbent. The surface characteristics of the quartz sand before and after modification were analyzed. Different amounts of modified quartz sand were then tested for their adsorption capacity, using raw water with an arsenic concentration of 500 ppb. Analysis showed that the surface area and average pore diameter of the quartz sand had increased significantly after modification, as did the amounts of iron, manganese, and aluminum found as surface elements. Using both Freundlich and Langmuir isotherm models to measure the effectiveness of arsenic adsorption by the modified quartz sand, it was found that the latter model, for monolayer adsorption, was more appropriate.

In many inventory systems, the effects of deterioration of physical goods have drawn much attention of various researchers in recent years. The more the deterioration is, the more the order quantity would be. According to such consideration, taking the deterioration rate into account is necessary. Thus, in this paper, I develop the two-warehouse partial backlogging inventory model introduced in Yang (2006) to incorporate three-parameter Weibull deterioration distribution. The objective is to derive the optimal replenishment policy that minimizes the net present value of total relevant cost per unit time. Two alternative models are compared based on the minimum cost approach. The study shows that the optimal solution not only exists but also is unique. Model 2 is still less expensive to operate than Model 1 in the proposed model. Finally, some numerical examples and sensitivity analysis on parameters are made to validate the results of the proposed inventory system.

Precoagulation is one of the effective pretreatments in membrane filtration. This process mitigates membrane fouling, which is the major drawback of membrane technology in drinking water and wastewater treatment. This study investigated the effects of precoagulation under different coagulation mechanisms on membrane fouling. Use of ultrasound in polytetrafluoroethylene (PTFE) membrane cleaning was also evaluated. In precoagulation, synthetic raw water was precoagulated using aluminum sulfate at different coagulation mechanisms, named electrostatic patch effect (EPE), charge neutralization (CN), and sweep flocculation (SW). Flocs produced from different coagulation mech- anisms exhibited different sizes, structures, and strengths. Likewise, the fouling type generated from each mechanism was demonstrated as pore blocking for EPE, cake formation for SW, and combination phenomenon for CN. Moreover, this study indicated that the membrane flux was enhanced in the sequence of EPE > CN > SW. The flux recovery rate after ultrasonic cleaning was in the sequence of SW > CN > EPE. Finally, this study evidenced that the floc characteristics from various coagulation mechanisms affected membrane per- formance, fouling types, and ultrasonic cleaning efficiency. DOI: 10.1061/(ASCE)EE.1943-7870.0000406. © 2012 American Society of Civil Engineers.

In this article, I extend Balkhi ((2001), 'On a Finite Horizon Production Lot Size Inventory Model for Deteriorating Items: An Optimal Solution', European Journal of Operational Research, 132, 210-223), by considering a generalised mathematical production-inventory model for deteriorating items with partial backlogging. The demand, production and backlogging rates are assumed to be continuous and varying with time. The objective is to find the optimal production restarting and stopping time to keep the total relevant cost as low as possible. To ascertain the optimal solution exists, the conditions for the total relevant cost in the system which attains its global minimum are provided. In addition, based on the minimum total relevant cost, an alternative among the proposed four cases is also suggested. Finally, a numerical example and sensitivity analysis is illustrated and some management insights are presented.

A persistent cell labeling dye and a novel microbial counting method were used to explore the effects of salinity on a microbial population in a reverse osmosis (RO) desalination system, and these clearly distinguished microbial cell multiplication from cell adherence. The results indicated that microbial multiplication is more active at the front of a seawater RO pressure vessel, while adhesion dominates the back of the vessel. A severe reduction in RO permeate flux and total dissolved solid (TDS) rejection were detected at low salinity, attributed to marked cell multiplication and release of extracellular polymeric substances, whilst a relatively stable flux was observed at medium and high salinity. The results from PCR-DGGE revealed the variation in microbial species distribution on the membrane with salinity. The results imply the critical role of membrane modification in biofouling mitigation in the desalination process.