Models for Flexible Supply Chain Network Design

Arguably Supply Chain Management (SCM) is one of the central problems in Operations Research and Management Science (OR/MS). Supply Chain Network Design (SCND) is one of the most crucial strategic problems in the context of SCM. SCND involves decisions on the number, location, and capacity, of production/distribution facilities of a manufacturing company and/or its suppliers operating in an uncertain environment. Specifically, in the automotive industry, manufacturing companies constantly need to examine and improve their supply chain strategies due to uncertainty in the parameters that impact the design of supply chains. The rise of the Asian markets, introduction of new technologies (hybrid and electric cars), fluctuations in exchange rates, and volatile fuel costs are a few examples of these uncertainties. Therefore, our goal in this dissertation is to investigate the need for accurate quantitative decision support methods for decision makers and to show different applications of OR/MS models in the SCND realm. In the first technical chapter of the dissertation, we proposed a framework that enables the decision makers to systematically incorporate uncertainty in their designs, plan for many plausible future scenarios, and assess the quality of service and robustness of their decisions. Further, we discuss the details of the implementation of our framework for a case study in the automotive industry. Our analysis related to the uncertainty quantification, and network's design performance illustrates the benefits of using our framework in different settings of uncertainty. Although this chapter is focused on our case study in the automotive industry, it can be generalized to the SCND problem in any industry. We have outline the shortcomings of the current literature in incorporating the correlation among design parameters of the supply chains in the second technical chapter. In this chapter, we relax the traditional assumption of knowing the distribution of the uncertain parameters. We develop a methodology based on Distributionally Robust Optimization (DRO) with marginal uncertainty sets to incorporate the correlation among uncertain parameters into the designing process. Further, we propose a delayed generation constraint algorithm to solve the NP-hard correlated model in significantly less time than that required by commercial solvers. Further, we show that the price of ignoring this correlation in the parameters increases when we have less information about the uncertain parameters and that the correlated model gives higher profit when exchange rates are high compared to the stochastic model (with the independence assumption). We extended our models in previous chapters by presenting capacity options as a mechanism to hedge against uncertainty in the input parameters. The concept of capacity options similar to financial options constitute the right, but not the obligation, to buy more commodities from suppliers with a predetermined price, if necessary. In capital-intensive industries like the automotive industry, the lost capital investment for excess capacity and the opportunity costs of underutilized capacity have been important drivers for improving flexibility in supply contracts. Our proposed mechanism for high tooling cost parts decreases the total costs of the SCND and creates flexibility within the structure of the designed SCNs. Moreover, we draw several insights from our numerical analyses and discuss the possibility of price negotiations between suppliers and manufacturers over the hedging fixed costs and variable costs. Overall, the findings from this dissertation contribute to improve the flexibility, reliability, and robustness of the SCNs for a wide-ranging set of industries.PHDIndustrial & Operations EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/145819/1/nsalehi_1.pd

Reusable, Relevant, Recordings: Creating Engaging & Evergreen Course Content

Research indicates that recorded course content that is shorter and more informal in both style and media format has the greatest impact on student engagement. Recording key concepts, facts, processes, principles, and/or procedures that are core to the curriculum can fully leverage reusable, relevant recordings. This session will provide a design framework for creating recordings that are granular and modular which allows you to repurpose recordings in multiple contexts. This makes the content not only reusable and evergreen but creates a recording process that is sustainable and scalable. Link to Resource: z.umn.edu/the3rs Higher Education

The Role of Immune System Dysfunction in Co-Existence of Neurological Disorders in Psoriasis

No Abstrac

A Guideline for Early Diagnosis of Autoimmune Epilepsy Based on Clinical Manifestations and Common Para-Clinical Tests

No Abstrac

Ispitivanje značajka domova djece s alergijskim rinitisom i astmom

The prevalence of allergic diseases, especially asthma and allergic rhinitis, has dramatically increased during the last decades. Mite and cockroach, which are the most common allergens in house dust, are the major indoor allergens in asthmatic and allergic rhinitis patients. The aim of this study was to compare the association between age of dwelling and some other home characteristics in asthmatic and allergic rhinitis children, who had positive skin prick test to mite and cockroaches, with allergic patient with negative skin test. Thirty-six asthmatic and allergic rhinitis children with positive skin prick test to mite and cockroach allergens, and 34 allergic rhinitis and asthmatic children with negative skin prick test to these allergens were enrolled in this study. Data on home characteristics, including age of homes, kind of carpeting, floor of home and number of rooms in the building, were collected by telephone questionnaire. The mean age of buildings was higher in the group of children sensitive to mite and cockroach (22.4±12.9 vs. 16.3±13.9 years), but the difference was not significant. However, when patients sensitive to mite only were compared to control patients, the difference was significant (p=0.025). There was no significant difference in the number of floor, rooms, kind of carpet and other features of building between the case and control group. There was a significant relationship between mite allergy and building age, which could be important for the policy of allergy control in the society. However, further studies are needed to clarify the association between more specific home characteristics and allergy diseases.Učestalost alergijskih bolesti, poglavito astme i alergijskog rinitisa, bilježi znatan porast posljednjih desetljeća. Grinje i žohari kao najčešći alergeni u kućnoj prašini glavni su alergeni na koje nailaze osobe s alergijom i alergijskim rinitisom u zatvorenom prostoru. Cilj ovoga istraživanja bio je usporediti povezanost starosti objekta i neke druge značajke domova kod djece s astmom i alergijskim rinitisom te s pozitivnim kožnim testom na grinje i žohare s vrijednostima istih kod djece s astmom i alergijskim rinitisom, ali s negativnim kožnim testom na grinje i žohare. U studiju je bilo uključeno 36 djece s astmom i alergijskim rinitisom te s pozitivnim kožnim testom na grinje i žohare i 34 djece s astmom i alergijskim rinitisom, ali s negativnim kožnim testom na grinje i žohare. Podatci o značajkama doma uključujući starost zgrade, vrst zidne obloge, kat i broj soba u zgradi prikupljeni su telefonskim anketiranjem roditelja. Srednja starost zgrade u kojoj žive bila je veća kod djece osjetljive na grinje i žohare nego u djece koja nisu pokazala osjetljivost na ove alergene (22,4±12,9 prema 16,3±13,9 years), ali razlika nije bila značajna. Međutim, kad su s kontrolnom skupinom uspoređena djeca osjetljiva samo na grinje, tada je razlika bila značajna (p=0,025). Nije bilo nikakve razlike između dviju skupina u odnosu na kat, broj soba, vrst zidne obloge i druge značajke zgrade. Dakle, utvrđena je značajna povezanost alergije na grinje i starosti zgrada, što bi moglo biti važno u planiranju aktivnosti za suzbijanje alergije u društvu. Potrebna su daljnja ispitivanja kako bi se pojasnila udruženost nekih specifičnih značajka zgrada i alergijskih bolesti

Flavonoids profile and antioxidant activity in flowers and leaves of hawthorn species (Crataegus spp.) from different regions of Iran

This study was undertaken to determine the total quantity of phenolic and flavonoids, as well as to find out about the HPLC quantification of some individual phenolic compounds (i.e. chlorogenic acid, vitexin 2"-O-rhamnoside, vitexin, rutin, hyperoside, quercetin, and isoquercetin) in flowers and leaves of 56 samples of different hawthorn species (Crataegus spp.) collected from different geographical regions of Iran. The amount of total phenolics ranges from 7.21 to 87.73 mg GAE/g in dry weight of the plant, and the total amount of flavonoids varied amongst species and in different plant organs ranging from 2.27 to 17.40 mg/g dry weight. Chlorogenic acid, vitexin, and vitexin 2"-O-rhamnoside were found to be the most abundant phenolic compounds in the extracts of hawthorn leaves. Meanwhile, chlorogenic acid, hyperoside, and rutin were the most abundant phenolic compounds in the extracts of hawthorn flowers in most genotypes. The antioxidant activity widely varied in species and in different organs of each individual plant, ranging from 0.9 to 4.65 mmol Fe++/g DW plant, calculated through the ferric-reducing antioxidant power (FRAP) method. Thus, this could provide valuable data for developing breeding strategies and plans; it can also help us in selecting genotypes with high phenolic contents for producing natural antioxidants and other bioactive compounds beneficial for food or the pharmaceutical industries

Competitive binding of E3 ligases TRIM26 and WWP2 controls SOX2 in glioblastoma

The pluripotency transcription factor SOX2 is essential for the maintenance of glioblastoma stem cells (GSC), which are thought to underlie tumor growth, treatment resistance, and recurrence. To understand how SOX2 is regulated in GSCs, we utilized a proteomic approach and identified the E3 ubiquitin ligase TRIM26 as a direct SOX2-interacting protein. Unexpectedly, we found TRIM26 depletion decreased SOX2 protein levels and increased SOX2 polyubiquitination in patient-derived GSCs, suggesting TRIM26 promotes SOX2 protein stability. Accordingly, TRIM26 knockdown disrupted the SOX2 gene network and inhibited both self-renewal capacity as well as in vivo tumorigenicity in multiple GSC lines. Mechanistically, we found TRIM26, via its C-terminal PRYSPRY domain, but independent of its RING domain, stabilizes SOX2 protein by directly inhibiting the interaction of SOX2 with WWP2, which we identify as a bona fide SOX2 E3 ligase in GSCs. Our work identifies E3 ligase competition as a critical mechanism of SOX2 regulation, with functional consequences for GSC identity and maintenance

Neurological manifestations as the predictors of severity and mortality in hospitalized individuals with COVID-19: a multicenter prospective clinical study

BACKGROUNDS: The reports of neurological symptoms are increasing in cases with coronavirus disease 2019 (COVID-19). This multi-center prospective study was conducted to determine the incidence of neurological manifestations in hospitalized cases with COVID-19 and assess these symptoms as the predictors of severity and death. METHODS: Hospitalized males and females with COVID-19 who aged over 18 years were included in the study. They were examined by two neurologists at the time of admission. All survived cases were followed for 8 weeks after discharge and 16 weeks if their symptoms had no improvements. RESULTS: We included 873 participants. Of eligible cases, 122 individuals (13.97%) died during hospitalization. The most common non-neurological manifestations were fever (81.1%), cough (76.1%), fatigue (36.1%), and shortness of breath (27.6%). Aging, male gender, co-morbidity, smoking, hemoptysis, chest tightness, and shortness of breath were associated with increased odds of severe cases and/or mortality. There were 561 (64.3%) cases with smell and taste dysfunctions (hyposmia: 58.6%; anosmia: 41.4%; dysguesia: 100%). They were more common among females (69.7%) and non-smokers (66.7%). Hyposmia/anosmia and dysgeusia were found to be associated with reduced odds of severe cases and mortality. Myalgia (24.8%), headaches (12.6%), and dizziness (11.9%) were other common neurological symptoms. Headaches had negative correlation with severity and death due to COVID-19 but myalgia and dizziness were not associated. The cerebrovascular events (n = 10) and status epilepticus (n = 1) were other neurological findings. The partial or full recovery of smell and taste dysfunctions was found in 95.2% after 8 weeks and 97.3% after 16 weeks. The parosmia (30.9%) and phantosmia (9.0%) were also reported during 8 weeks of follow-up. Five cases with mild headaches and 5 cases with myalgia were reported after 16 weeks of discharge. The demyelinating myelitis (n = 1) and Guillain-Barré syndrome (n = 1) were also found during follow-up. CONCLUSION: Neurological symptoms were found to be prevalent among individuals with COVID-19 disease and should not be under-estimated during the current pandemic outbreak

The Hospitalization Rate of Cerebral Venous Sinus Thrombosis before and during COVID-19 Pandemic Era: A Single-Center Retrospective Cohort Study

Objectives: There are several reports of the association between SARS-CoV-2 infection (COVID-19) and cerebral venous sinus thrombosis (CVST). In this study, we aimed to compare the hospitalization rate of CVST before and during the COVID-19 pandemic (before vaccination program). Materials and methods: In this retrospective cohort study, the hospitalization rate of adult CVST patients in Namazi hospital, a tertiary referral center in the south of Iran, was compared in two periods of time. We defined March 2018 to March 2019 as the pre-COVID-19 period and March 2020 to March 2021 as the COVID-19 period. Results: 50 and 77 adult CVST patients were hospitalized in the pre-COVID-19 and COVID-19 periods, respectively. The crude CVST hospitalization rate increased from 14.33 in the pre-COVID-19 period to 21.7 per million in the COVID-19 era (P = 0.021). However, after age and sex adjustment, the incremental trend in hospitalization rate was not significant (95% CrI: -2.2, 5.14). Patients \u3e 50-year-old were more often hospitalized in the COVID-19 period (P = 0.042). SARS-CoV-2 PCR test was done in 49.3% out of all COVID-19 period patients, which were positive in 6.5%. Modified Rankin Scale (mRS) score ≥3 at three-month follow-up was associated with age (P = 0.015) and malignancy (P = 0.014) in pre-COVID period; and was associated with age (P = 0.025), altered mental status on admission time (P\u3c0.001), malignancy (P = 0.041) and COVID-19 infection (P = 0.008) in COVID-19 period. Conclusion: Since there was a more dismal outcome in COVID-19 associated CVST, a high index of suspicion for CVST among COVID-19 positive is recommended