bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of progress made by dairy and beef herds enrolled in the Minnesota Johne's Disease Control Program
Authors: Wells Scott J. , Hartmann William L. , Anderson Paul L.
Published: December 2008

Objective—To evaluate progress made by cattle herds in the control of paratuberculosis (Johne's disease) through participation in the Minnesota Johne's Disease Control Program (MNJDCP).

Design—Retrospective records analysis.

Sample Population—Data for dairy and beef herds participating in the MNJDCP.

Procedures—Data for the MNJDCP were collected for analyses. Outcome measures included changes in numbers of participating cattle producers, risk assessment scores, and within-herd seroprevalence of Johne's disease by year of program participation.

Results—Results revealed steady increases in program participation by cattle producers in Minnesota over time, with > 30% of dairy producers and 2% of beef producers in the state participating by the end of 2006. Despite risk of introduction of Johne's disease to cattle herds through continued introduction of cattle from other herds, dairy and beef herds in the Management Program of the MNJDCP reduced their on-farm risk assessment scores during the program. Dairy herds in the Management Program reduced their mean within-herd seroprevalence 1.1% during the first year, 2.6% during the first 2 years, and 4.0% during the first 3 years of program participation. Significant within-herd seroprevalence reduction was also detected for beef herds that participated in the Management Program for at least 3 years.

Conclusions and Clinical Relevance—This study revealed a reduction in the risk of withinherd transmission of Johne's disease and seroprevalence over time in dairy and beef herds in the Management Program of the MNJDCP. This is consistent with a positive effect of the program for the control of Johne's disease in cattle.
Autonomous Vehicles Navigation with Visual Target Tracking: Technical Approaches
Authors: Jia Zhen , Balasuriya Arjuna , Challa Subhash
Published: December 2008

This paper surveys the developments of last 10 years in the area of vision based target tracking for autonomous vehicles navigation. First, the motivations and applications of using vision based target tracking for autonomous vehicles navigation are presented in the introduction section. It can be concluded that it is very necessary to develop robust visual target tracking based navigation algorithms for the broad applications of autonomous vehicles. Then this paper reviews the recent techniques in three different categories: vision based target tracking for the applications of land, underwater and aerial vehicles navigation. Next, the increasing trends of using data fusion for visual target tracking based autonomous vehicles navigation are discussed. Through data fusion the tracking performance is improved and becomes more robust. Based on the review, the remaining research challenges are summarized and future research directions are investigated.
The Effect of Monoterpenes on Swarming Differentiation and Haemolysin Activity in Proteus mirabilis
Authors: Echeverrigaray Sergio , Michelim Lessandra , Longaray Delamare Ana  Paula , Andrade Cristiane  Paim , Pinto da Costa Sérgio  Olavo , Zacaria Jucimar
Published: December 2008

Urinary tract infection by Proteus mirabilis depends on several virulence properties that are coordinately regulated with swarming differentiation. Here we report the antibacterial and anti-swarming effect of seventeen terpenoids, and the effect of subinhibitory concentrations of five selected terpenoids on swarming, biofilm formation and haemolysin activity. The results showed that all the terpenes evaluated, particularly oxygenated terpenoids, inhibited P. mirabilis with MIC values ranging between 3 and 10 mg/L. Moreover, citral, citronellol and geraniol effectively inhibit P. mirabilis swarming in a dose dependent manner, reducing swimming/swarming cell differentiation and haemolysin activity at 1/10 MIC concentration. The inhibition of P. mirabilis swarming and virulence factor expression by selected oxygenated terpenoids suggest that essential oils with high concentration of these compounds have the potential to be developed as products for preventing P. mirabilis infections.
Binding of Cationic Bis-porphyrins Linked with p- or m-Xylylenediamine and Their Zinc(II) Complexes to Duplex DNA
Authors: Ishikawa Yoshinobu , Yamakawa Naoki , Uno Tadayuki
Published: December 2008

Spectroscopic, viscometric, and molecular docking analysis of binding of cationic bis-porphyrins linked with p- or m-xylylenediamine (H2pXy and H2mXy) and their zinc(II) complexes (ZnpXy and ZnmXy) to duplex DNA are described. H2pXy and H2mXy bound to calf thymus DNA (CTDNA) stronger than unichromophoric H2TMPyP, and showed exciton-type induced circular dichroism spectra of their Soret bands. The H2TMPyP-like units of the metal-free bis-porphyrins did not intercalate into CTDNA, and thus the binding mode is outside binding with intramolecular stacking. ZnpXy showed favorable binding to A·T over G·C region, and should lie in the major groove of A·T region.
Photodegradation of Acidolysis Lignin from BCMP
Authors: Azadfallah Mohammad , Mirshokraei Seyed  Ahmad , Latibari Ahmad  Jahan
Published: December 2008

A mild acidic dioxane extraction method was employed to isolate lignin from hardwood bleached chemimechanical pulp (BCMP). The isolated lignin was then purified and undergone elemental analysis. To study the photodegradation behavior, the lignin samples were impregnated onto the Whatman filter papers and irradiated with UV light for various periods. The photolyzed lignin was then recovered and analyzed by 1H-NMR spectroscopy. Phenylpropane-based formula (C9) of CMP pulp lignin and the photolyzed samples were then established with elemental analysis and 1H-NMR spectroscopy data. The results indicated that the benzaldehyde and benzoic acid type compounds were the main photodegradation products of BCMP lignin. The lignin photodegradation probably involved the degradation of phenylcoumaran units. Irradiation also increased the phenolic hydroxyl group content and decreased that of methoxyl groups, due to demethoxylation. The degrees of aromatic ring condensation were increased upon continuing the irradiation time, which imples the formation of condensed structures in photolyzed lignin.
A Novel Synthetic Approach to C-Glycosyl-D- and L-Alanines
Authors: Martinková Miroslava , Gonda Jozef , Raschmanová Jana , Novodomská Alexandra , Kožíšek Jozef , Perasinová Lucia
Published: December 2008

C-Glycosyl-(S)- and (R)-alanines 12a and 12b were synthesized from the known β-C-glycoside 1. The nitrogen function was introduced by aza-Claisen rearrangement of the allylic thiocyanate 7, derived from the corresponding alcohol 6. The absolute configuration of the newly created chiral carbon center (C-3) was assigned by X-ray diffraction analysis of the intermediate 3(S)-isothiocyanato-D-glycero-D-galacto-decose 8a.
Synthesis of Bis-ureas from Bis(o-nitrophenyl) Carbonate
Authors: Turoczi Maria-Cristina , Simon Monika , Badea Valentin , Csunderlik Carol
Published: December 2008

A general method for the preparation of bis-ureas from bis(o-nitrophenyl) carbonate has been developed. Directional urea synthesis is achieved by sequential amine addition to bis(o-nitrophenyl) carbonate in two steps: in the first step bis(o-nitrophenyl) carbonate is reacted with benzylamine to form benzyl-o-nitrophenyl carbamate; in the second step the carbamate is reacted with a variety of diamines in toluene to yield bis-ureas.
Objective Error Criterion for Evaluation of Mapping Accuracy Based on Sensor Time-of-Flight Measurements
Authors: Barshan Billur
Published: December 2008

An objective error criterion is proposed for evaluating the accuracy of maps of unknown environments acquired by making range measurements with different sensing modalities and processing them with different techniques. The criterion can also be used for the assessment of goodness of fit of curves or shapes fitted to map points. A demonstrative example from ultrasonic mapping is given based on experimentally acquired time-of-flight measurements and compared with a very accurate laser map, considered as absolute reference. The results of the proposed criterion are compared with the Hausdorff metric and the median error criterion results. The error criterion is sufficiently general and flexible that it can be applied to discrete point maps acquired with other mapping techniques and sensing modalities as well.
Comparison of a Resonant Mirror Biosensor (IAsys) and a Quartz Crystal Microbalance (QCM) for the Study on Interaction between Paeoniae Radix 801 and Endothelin-1
Authors: Huang Jiadong , Lin Qing , Yu Jinghua , Ge Shenguang , Li Jing , Yu Min , Zhao Zixia , Wang Xinsheng , Zhang Xiuming , He Xiaorui , Yuan Liang , Yin Huijun , Osa Tetsuo , Chen Keji , Chen Qiang
Published: December 2008

A resonant mirror biosensor, IAsys, and a quartz crystal microbalance (QCM) are known independently as surface sensitive analytical devices capable of label-free and in situ bioassays. In this study, an IAsys and a QCM are employed for a new study on the action mechanism of Paeoniae Radix 801 (P. radix 801) by detecting the specific interaction between P. radix 801 and endothelin-1 (ET-1). In the experiments, ET-1 was immobilized on the surfaces of the IAsys cuvette and the QCM substrate by surface modification techniques, and then P. radix 801 solution was contacted to the cuvette and the substrate, separately. Then, the binding and interaction process between P. radix 801 and ET-1 was monitored by IAsys and QCM, respectively. The experimental results showed that P. radix 801 binds ET-1 specifically. The IAsys and QCM response curves to the ET-1 immobilization and P. radix 801 binding are similar in reaction process, but different in binding profiles, reflecting different resonation principles. Although both IAsys and QCM could detect the interaction of P. radix 801 and ET-1 with high reproducibility and reliability through optimization of the ET-1 coating, the reproducibility and reliability obtained by IAsys are better than those obtained by QCM, since the QCM frequency is more sensitive to temperature fluctuations, atmospheric changes and mechanical disturbances. However, IAsys and QCM are generally potent and reliable tools to study the interaction of P. radix 801 and ET-1, and can conclusively be applied to the action mechanism of P. radix 801.
Why Do We Observe Stockless Operations on the Internet? Stockless Operations Under Competition
Authors: Sun Daewon , Ryan Jennifer K. , Shin Hojung
Published: December 2008

Due to the proliferation of electronic commerce and the development of Internet technologies, many firms have considered new pricing‐inventory models. In this paper, we study the role of stockless (i.e., zero‐inventory) operations in online retailing by a considering duopoly competition in which two retailers compete to maximize profit by jointly optimizing their pricing and inventory decisions. In our model, the retailers are allowed to choose either an in‐stock policy or stockless operations with a discounted price. We first present the characteristics and properties of the equilibrium. We then demonstrate that the traditional outcome of asymmetric Bertrand competition is observed under head‐to‐head competition. However, when the two firms choose different operational policies, with corresponding optimal pricing, they can share the market under certain conditions. Finally, we report interesting observations on the interaction between pricing and inventory decisions obtained from an extensive computational study.
Flexible Backup Supply and the Management of Lead‐Time Uncertainty
Authors: Kouvelis Panos , Li Jian
Published: December 2008

We consider replenishment decisions for a constant rate demand environment from a supplier with uncertain lead times. We study the potential use of a flexible backup supplier as an emergency response to accurate lead‐time information arriving at (or close after) the beginning of the demand interval and well after an original order with the stochastic lead‐time supplier has been placed. The emergency response decisions involve whether to order and how much from the flexible backup supplier, with the objective of minimizing the cost of meeting demand. We derive the optimal emergency‐response policy and clearly outline its implications on the optimized safety lead time of the original order placement and on the cost of meeting demand. We examine the impact on the use of the flexible backup supplier of factors like the arrival time of accurate lead‐time information and the response lead time of the backup supplier. We further study the potential benefits of the use of the flexible backup supplier in a dual role: as one of the two suppliers in a redundant supply system assigned to originally meet the demand and as an emergency response to later‐arriving lead‐time information. Our numerical studies illustrate the benefits from the use of the flexible backup supplier as an emergency response, but for reasonable purchase premiums and short lead times of flexible backup supply options, their use in a dual (regular and emergency response) role often leads to improved performance over safety lead‐time single and uncertain lead‐time supplier‐replenishment strategies. The benefits of the backup supply options are accentuated the higher the lead‐time uncertainty of the stochastic lead‐time supplier is.
Sourcing Through Auctions and Audits
Authors: Chen Ying‐Ju , Seshadri Sridhar , Zemel Eitan
Published: December 2008

Buyers often find that obtaining complete information about suppliers is costly. In such scenarios, there is a trade‐off between the costs of obtaining information and the benefits that accrue to the owners of such information. There are also various ways in which the missing information can be obtained or inferred. In this paper, we compare the efficiency of obtaining information via the classical mechanism design approach, which relies on the information available before the contracts are designed, with that of an “audit‐based” approach, which relies on the information obtained after the fact.

In our model, a single buyer (the Stackelberg leader) wishes to procure a package of products or services from various competing suppliers that possess private cost information. We allow for arbitrary cost and revenue functions and can incorporate multiple cost and revenue drivers. We show how the buyer can optimize her profit and at the same time coordinate the channel by using a contract scheme involving auctions, audits, and profit sharing. We also examine the behavior of this mechanism when the supplier can exert effort to reduce cost but the cost of effort cannot be verified. We propose several mechanisms for different precontract informational scenarios and compare their performance.
Experience, Service Operations Strategy, and Services as Destinations: Foundations and Exploratory Investigation
Authors: Voss Chris , Roth Aleda V. , Chase Richard B.
Published: December 2008

This paper explores the customer experience paradigm as it pertains to service operations strategy and design. First, we operationally define and discuss the concept of customer experience. In this context, we propose a reframing of the strategic role of operations strategy as one of choreographing experience‐centric services. We then introduce the concept of services as destinations as an emerging business model for classifying experiential service strategies. Our conceptual typology of experience‐based strategies uses two dimensions: (1) the depth of use of experience as a source of value creation, ranging from brand experience to the services as a destinations business model, and (2) the degree of integration of experience internally within the firm. Using this conceptual typology, we develop five propositions and use multiple cases to illustrate firms' use of these experience strategies. Laying the groundwork for future research, we highlight insights from the qualitative, multiple‐case data as they pertain to service operations strategy and the business model that employs services as destinations. A number of questions for further research are suggested.
Assessment of Patient Classification in Appointment System Design
Authors: Cayirli Tugba , Veral Emre , Rosen Harry
Published: December 2008

This paper investigates two approaches to patient classification: using patient classification only for sequencing patient appointments at the time of booking and using patient classification for both sequencing and appointment interval adjustment. In the latter approach, appointment intervals are adjusted to match the consultation time characteristics of different patient classes. Our simulation results indicate that new appointment systems that utilize interval adjustment for patient class are successful in improving doctors' idle time, doctors' overtime and patients' waiting times without any trade‐offs. Best performing appointment systems are identified for different clinic environments characterized by walk‐ins, no‐shows, the percentage of new patients, and the ratio of the mean consultation time of new patients to the mean consultation time of return patients. As a result, practical guidelines are developed for managers who are responsible for designing appointment systems.
Pricing, Allocation, and Overbooking in Dynamic Service Network Competition When Demand Is Uncertain
Authors: Mookherjee Reetabrata , Friesz Terry L.
Published: December 2008

We study the problem of combined pricing, resource allocation, and overbooking by service providers involved in dynamic noncooperative oligopolistic competition on a network that represents the relationships of the providers to one another and to their customers when service demand is uncertain. We propose, analyze, and compute solutions for a model that is more general than other models reported in the revenue management literature to date. In particular, previous models typically consider only three or four of five key revenue management features that we have purposely built into our model: (1) pricing, (2) resource allocation, (3) dynamic competition, (4) an explicit network, and (5) uncertain demand. Illustrative realizations of the abstract problem we study are those of airline revenue management and service provision by companies facing resource constraints. Under fairly general regularity conditions, we prove existence and uniqueness of a pure strategy Nash equilibrium for dynamic oligopolistic service network competition described by our model. We also show, for an appropriate notion of regularity, that competition leads to the underpricing of network services, a finding numerically illustrated by an example of intermediate size. Our proposed algorithm can be implemented using well‐known off‐the‐shelf commercial software.
Revenue Management in Business Services
Authors: Dietrich Brenda , Paleologo Giuseppe A. , Wynter Laura
Published: December 2008

A significant portion of the services industry is focused on providing services (medical, legal, financial, personal, and travel) to individuals. However, studies have shown that a less visible but rapidly growing segment of the service sector comprises firms that provide business functions to other businesses. The sector covers tasks such as payroll processing, procurement, and information systems management, as well as business consulting, technical support, call center operations, and software development. Firms may choose to purchase, rather than perform, these business functions to reduce costs, to mitigate risk, or simply to focus on their processes that provide marketplace differentiation. Transferring a business function from within a firm to an outside supplier is often called “outsourcing”; when the supplier provides the service from a lower‐cost country, it is called “offshoring.” The risks and benefits of outsourcing to the firm purchasing a business service have been studied in some detail by both academics and consultants. In this paper, we outline revenue management issues faced by business service providers and describe some new opportunities for the use of analytic methods in the service science sector.
Product Reuse Economics in Closed‐Loop Supply Chain Research
Authors: Atasu Atalay , Guide V. Daniel R. , VanWassenhove Luk N.
Published: December 2008

This paper provides a critical review of analytic research on the business economics of product reuse inspired by industrial practice. Insights and critical assumptions are provided for each paper. We further classify the research into four streams: industrial engineering/operations research, design, strategy, and behavioral, and present a framework linking these streams. We find that some modeling assumptions risk being institutionalized, and suggest a renewed exploration of industrial practice. Future research should also include empirical work on consumer behavior, product diffusion, and valuation of returns.
Approximations to Optimal k‐Unit Cycles for Single‐Gripper and Dual‐Gripper Robotic Cells
Authors: Geismar H. Neil , Chan Lap Mui Ann , Dawande Milind , Sriskandarajah Chelliah
Published: December 2008

We consider the problem of scheduling operations in bufferless robotic cells that produce identical parts using either single‐gripper or dual‐gripper robots. The objective is to find a cyclic sequence of robot moves that minimizes the long‐run average time to produce a part or, equivalently, maximizes the throughput. Obtaining an efficient algorithm for an optimum k‐unit cyclic solution ( k ≥ 1) has been a longstanding open problem.

For both single‐gripper and dual‐gripper cells, the approximation algorithms in this paper provide the best‐known performance guarantees (obtainable in polynomial time) for an optimal cyclic solution. We provide two algorithms that have a running time linear in the number of machines: for single‐gripper cells (respectively, dual‐gripper cells), the performance guarantee is 9/7 (respectively, 3/2). The domain considered is free‐pickup cells with constant intermachine travel time. Our structural analysis is an important step toward resolving the complexity status of finding an optimal cyclic solution in either a single‐gripper or a dual‐gripper cell. We also identify optimal cyclic solutions for a variety of special cases. Our analysis provides production managers valuable insights into the schedules that maximize productivity for both single‐gripper and dual‐gripper cells for any combination of processing requirements and physical parameters.
Dynamic Procurement, Quantity Discounts, and Supply Chain Efficiency
Authors: Erhun Feryal , Keskinocak Pinar , Tayur Sridhar
Published: December 2008

We study a model with a single supplier and a single buyer who interact multiple times before the buyer sells her product in the end‐consumer market. We show that when the supplier uses a wholesale price contract, even under perfect foresight, the supplier, the buyer, and the end consumers benefit from multiple trading opportunities versus a one‐shot procurement agreement.
Pom Forum: Operations Management's Next Source of Galvanizing Energy?
Authors: Hayes Robert H.
Published: December 2008

I am concerned that the field of production and operations management is losing direction and cohesion, as well as the battle for the best new faculty, student enrollments, and research funding. This problem is not due to a lack of interesting initiatives but because our several active subfields are pulling us in different directions and causing our common ground to shrink. This is at a time when firms around the globe are facing perplexing operating problems that are apparently not resolvable through existing theories and techniques.

Other academic fields have experienced similar strains at certain points, and they tend to get to that point following a progression like those that production and operations management has witnessed three times in the past 50 years. After briefly describing these past histories, I propose that we are near the end of one cycle and need a new jolt of energy to begin another.

The problems of coordinating the complex collaborations among networked organizations (the Coordination of Operations across Multiple Organizations) are becoming increasingly important in today's economy. I suggest that intensive multiteam studies of such networks could provide new insights into these pressing problems, stimulate creativity, and help reunify our field.
Drivers and Enablers That Foster Environmental Management Capabilities in Small‐ and Medium‐Sized Suppliers in Supply Chains
Authors: Lee Su‐Yol , Klassen Robert D.
Published: December 2008

The limited capabilities and resources available within many small‐ and medium‐sized enterprises frequently hamper an effective response to environmental pressures, which in turn hurts large buying firms (i.e., customers). Using a case study method with multiple suppliers of two large buying firms, we mapped factors that initiated and improved environmental capabilities in small‐ and medium‐sized enterprises over time. Through several specific mechanisms, buyers' green supply chain management initiated and then enabled the improvement of suppliers' environmental capabilities. Independent of buyers, internal championing of environmental concerns also provided an impetus for small‐ and medium‐sized enterprise suppliers to acquire resources outside the supply chain. Thus, synergistic linkages emerged in supportive buyer‐supplier relationships, resource acquisition, and capability development. When these findings are combined with earlier research on larger suppliers, an integrative framework emerges that provides direction for suppliers, buyers, and public agencies seeking to improve environmental performance.
Product Portfolio Strategies: The Case of Multifunction Products
Authors: Chen Yuwen , Vakharia Asoo J. , Alptekinoǧlu Aydin
Published: December 2008

Motivated by the proliferation of multifunction products, we investigate product portfolio decisions of a single firm by analyzing the impact of three major factors. First, because multifunction products provide complete or partial functionalities of single‐function products, we incorporate substitution or cannibalization effects between the potential products. Second, we explicitly model the variable costs of manufacturing the single‐function and multifunction products. Third, we examine the firm's pricing decisions because of their impact on the degree of cannibalization between the multifunction product and one or more single‐function products. Using an economic model, we first characterize the firm's optimal product portfolio (through a quantity‐based decision), which in turn determines the market equilibrium prices for each product in its portfolio. Some of the unique insights stemming from our analysis are: (a) the optimal product portfolio choice is driven primarily by maximum profit margins for the single‐function products weighted by the demand substitution effects; and (b) from a product design perspective, the complete functionality of the base single‐function product is always included in the optimal product offering, but this is not necessarily the case with the complete functionality of the nonbase single‐function product.
Optimal Contract Design for Mixed Channels Under Information Asymmetry
Authors: Mukhopadhyay Samar K. , Zhu Xiaowei , Yue Xiaohang
Published: December 2008

The mixed‐channel model is becoming increasingly popular in the marketplace. In this model, a firm selling through the traditional supply chain of wholesaler and retailer opens a direct channel to the customer through Internet sales. Because both channels have their respective advantages, the manufacturer is attracted to this business model. However, it also leads to channel conflict, with the retailer feeling threatened by direct competition. One way of eliminating the possibility of this channel conflict, where the retailer is allowed to add value to the product to differentiate its offering to the customers, is proposed in this paper. The retailer is also given full authority to make pricing decisions. This paper presents a model, under this scenario, of obtaining optimum pricing decisions by both parties, the amount of value added by the retailer, and the manufacturer's wholesale price to the retailer. Our model incorporates information asymmetry, where the manufacturer has incomplete information about the retailer's cost of adding value. We obtain closed‐form contracts with incomplete information and compare them with those with complete channel coordination. We also develop a number of managerial guidelines and identify future research topics.
EFFECT OF SURFACE CHARACTERISTICS OF POLYHYDROXYALKANOATES (PHAs) ON METABOLIC ACTIVITIES AND MORPHOLOGY OF HUMAN SCHWANN CELLS-LIKE (hSCs-LIKE)
Authors: Yu Bo-Yi , Chen Po-Ya , Sun Yi-Ming , Young Tai-Horng
Published: December 2008

Polyhydroxyalkanoates (PHAs) is a newer family of biomaterials for tissue engineering applications. The objective of this study is to investigate the behaviors of human Schwann cells-like (hSCs-like) on various PHA films. The surface characteristics of PHA films were varied by the content of 3-hydroxyvalerate (HV) or 3-hydroxyhexanoate (HHx) and by the film preparation methods such as compression-molding and solvent-casting. Hyaluronic acid (HA) and poly(L-lysine) (PLL) were further applied on to improve the growth of hSCs-like on PHA membranes. The hSCs-like isolated from human body (MATERIALS AND METHODS) would have strong metabolic activities and produce many extracellular matrix (ECM). When HV content increased, there was a reduction in the crystallinity and the hydrophoicity of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) membranes. Despite that these different surface characteristics did not show significant effect on the metabolic activities of hSCs-like, these would affect adhering HA. Hyaluronic acid (HA)-coated PHA membranes could improve the metabolic activities and decrease the death ratio of hSCs-like. However, the condition of PLL coating has no obvious influence on the activities of hSCs.
A TELE-EMERGENT SYSTEM FOR LONG-TERM ECG MONITORING OVER WIRELESS SENSOR NETWORK
Authors: Hsiao C. C. , Lee R. G. , Chou I. C. , Lin C. C. , Huang D. Y.
Published: December 2008

This paper presents the design and implementation of a tele-emergent system to provide constant monitoring of cardiac patients. Our system is consisted of a user integration device attached to the patient, a wireless sensor network (WSN) and a medical gateway installed in the patient's home, and a server set up in the hospital. The user integration device includes Electrocardiogram (ECG) signal acquisition and processing circuit utilizing a "Modified So and Chan" QRS detection algorithm to discriminate the R signal wave and calculate RR intervals to subsequently detect abnormal Heart Rate Variability (HRV), and a Bluetooth transmission module to communicate with WSN. The WSN which is consisted of wireless sensor nodes with power-saving scheme is used to relay the ECG data to the medical gateway for ubiquitous monitoring at home. The medical gateway includes the heart disease symptom recognition system to further analyze the ECG data and recognize the symptoms of serious heart diseases, and a General Packet Radio Service (GPRS) module with Multimedia Messaging Service (MMS) to communicate with the server in the hospital. The server in the hospital can passively process the MMS messages from the medical gateway, and actively send commands to the medical gateway to acquire the needed ECG data from the patient. With our integrated system it is possible to provide real-time and long-term monitoring of physiological data for cardiac patients which is vital for the patients' medical care.
ANTINOCICEPTIVE EFFECT OF MORPHINE IN α-CHLORALOSE AND ISOFLURANE ANESTHETIZED RATS USING BOLD fMRI
Authors: Chen Chin-Mei , Shih Yen-Yu I. , Siow Tiing-Yee , Chiang Yun-Chen , Chang Chen , Jaw Fu-Shan
Published: December 2008

Blood oxygenation level dependent functional magnetic resonance imaging technique was used to explore the antinociceptive effect of morphine in the rat brain under α-chloralose and isoflurane anesthesia. Formalin was used as a pain-testing model which could produce significant activation in various brain areas. The results also showed that morphine pretreatment modulate neurovascular activities evoked by formalin stimulation, especially in cingulate cortex, somatosensory cortex, caudate putamen, visual cortex, and hippocampus. The present study identified the brain areas involved in modulating nociception.
Crystal Engineering Approach To Design Colorimetric Indicator Array To Discriminate Positional Isomers of Aromatic Organic Molecules
Authors: Trivedi Darshak R. , Fujiki Yuzo , Fujita Norifumi , Shinkai Seiji , Sada Kazuki
Published: December 2008

Discriminating by color: A 2D colorimetric indicator array has been designed by a crystal engineering approach (N⋅⋅⋅HO hydrogen bonding and charge‐transfer complexation) involving solid‐state co‐grinding for the visual discrimination of positional isomers of dihydroxynaphthalene. Factors governing the close packing of π planes, and hence color of the complex, were determined by single‐crystal X‐ray analysis, allowing fine tuning by crystal engineering.

magnified image

A 2D colorimetric indicator array to discriminate isomers of dihydroxynaphthalene has been designed by using a crystal engineering concept combined with solid‐state co‐grinding and charge‐transfer complexation. The N⋅⋅⋅HO supramolecular synthon between the pyridyl N atom of the probe and hydroxy group of the analyte has been observed in all reported single‐crystal X‐ray structures of resultant CT complexes. Solid‐state co‐grinding with aromatic solids easily provided the highly concentrated solvent‐free conditions required to promote the formation of charge‐transfer complexes with brighter color changes. Probe D (N,N′‐bis‐(4‐pyridyl)pyromellitic diimide) showed an excellent ability to discriminate eight isomers of dihydroxynaphthalene with a wide variety of colors of the resultant CT complexes.
Stimulating personality: Ethical criteria for deep brain stimulation in psychiatric patients and for enhancement purposes
Authors: Synofzik Matthis , Schlaepfer Thomas E.
Published: December 2008

Within the recent development of brain‐machine‐interfaces deep brain stimulation (DBS) has become one of the most promising approaches for neuromodulation. After its introduction more than 20 years ago, it has in clinical routine become a successful tool for treating neurological disorders like Parkinson's disease, essential tremor and dystonia. Recent evidence also demonstrates efficacy in improving emotional and cognitive processing in obsessive‐compulsive disorder and major depression, thus allowing new treatment options for treatment refractory psychiatric diseases, and even indicating future potential to enhance functioning in healthy subjects. We demonstrate here that DBS is neither intrinsically unethical for psychiatric indications nor for enhancement purposes. To gain normative orientation, the concept of “personality” is not useful – even if a naturalistic notion is employed. As an alternative, the common and widely accepted bioethical criteria of beneficence, non‐maleficence, and autonomy allow a clinically applicable, highly differentiated context‐ and case‐sensitive approach. Based on these criteria, an ethical analysis of empirical evidence from both DBS in movement disorders and DBS in psychiatric disease reveals that wide‐spread use of DBS for psychiatric indications is currently not legitimated and that the basis for enhancement purposes is even more questionable. Nevertheless, both applications might serve as ethically legitimate, promising purposes in the future.
Contacting the brain – aspects of a technology assessment of neural implants
Authors: Decker Michael , Fleischer Torsten
Published: December 2008

The public interest in neural implants has grown considerably in recent years. Progress within related research areas in combination with increasing – albeit overly optimistic and indiscriminate – mass media coverage have led to the impression that the possibilities of neural prosthetics have grown enormously. But a closer look reveals that the reasons for the intensified interest are varied and cannot be attributed to technical progress alone. Some neural prostheses that have been under development for many years have not left the clinical development phase despite intensive research activities. Other implants, like cardiac pacemakers and cochlea implants, are mature products that have already been implanted in a large number of patients.

From the public perspective and in media reports, progress in the development of neural implants is associated with new achievements in other fields of neuroscience. Communications on new applications of functional magnetic resonance imaging (fMRI) may suggest that a number of cognitive functions are now easily accessible with technological means. The fact that the interpretation of the results of fMRI studies depends on many conditions and is partly disputed also within the scientific community has been discussed in many publications but only very limited, in the general media. Besides this, research results and implementations in the area of electroencephalography and magnetoencephalography have sparked further debate on the question of free will, on determinism and indeterminism, and have attracted a large media response.

The purpose of this paper is to discuss some societal and ethical aspects of neural implants from a technology assessment perspective. Technology assessment (TA) aims at providing knowledge about impacts and consequences of (new) technologies as well as about political and societal ways of dealing with them. It reflects about implementation conditions of technology and potential technology conflicts. Over the last years, neural implants became a subject for TA since they have gained a higher attention in both the political arena and the general public. Especially the ethical and social implications of technologies that electrically stimulate the brain and the possibilities of changing personality traits, changing moods, and perhaps enhancing human cognitive capabilities are central issues in related discussions. In this paper, we want to briefly summarize some of the key arguments as well as topics for future discussion and research.
Meeting report: Deep brain stimulation in interdisciplinary perspectives
Authors: Clausen Jens
Published: December 2008

A Meeting report on the Neuroethics Research Workshop ‘Deep Brain Stimulation’ held September 26–27, 2008, in Halifax/Nova Scotia, Canada
Das Spurenelement Iod. Zu wenig und zu viel schadet dem Organismus
Authors: Anke Manfred , Arnhold Winfried
Published: December 2008

Iod ist ein lebenswichtiges chemisches Element. Der Iodbedarf Erwachsener beträgt 1 μg/kg Körpergewicht, empfohlen wird die Aufnahme von 2 μg/kg Körpergewicht. Iodmangel führt zu verschiedenen Krankheitsbildern, von denen der so genannte “Kropf” das bekannteste ist. Doch nicht nur Iodmangel ist gefährlich: Bei einem Konsum von > 7 μg/kg können toxische Nebenwirkungen auftreten, die bei einem schnellen Übergang vom Iodmangel zu einer bedarfsbedingten Iodversorgung bei iodsensitiven Personen (häufig sind es ältere Frauen) zu einer Schilddrüsenüberfunktion führen.
Mikroevolution oder Faunenverfälschung?
Authors: Baier Felix
Published: December 2008

In Heidelberg fielen in den vergangenen Jahren vermehrt melanistische – schwarze – Exemplare der Mauereidechse (Podarcis muralis merremius) auf. Haben sich die Umweltbedingungen am Neckar derart verändert, dass eine schwarze Eidechse einen Selektionsvorteil erlangt? Oder kann das Vorkommen der schwarzen Tiere am Neckar gar nicht durch natürliche Faktoren erklärt werden, weil die Tiere einfach ausgesetzt wurden? Teilnehmer des Heidelberger Life‐Science Lab suchten mit molekularbiologischen Methoden nach einer Erklärung für das Phänomen.
Bistable Molecular Switches Based on Linkage Isomerization in Ruthenium Polypyridyl Complexes with a Ligand‐Bound Ambidentate Motif
Authors: Johansson Olof , Johannissen Linus O. , Lomoth Reiner
Published: December 2008

Electron‐transfer‐induced linkage isomerization was investigated in a series of bis‐tridentate Ru polypyridyl complexes [Ru(L‐X‐OH)(Y‐tpy)]2+ with ambidentate ligand L‐X‐OH=bpy‐C(R)(OH)‐py (bpy=2,2′‐bipyridine; py=pyridine; R=H, Me, Ph, or tBu) and spectator ligand Y‐tpy (tpy=2,2′:6′,2′′‐terpyridine; Y=p‐tolyl, p‐PhCO2Me, Cl, OEt, N‐pyrrolidine). The ligand‐bound ambidentate motif switches reversibly between N and O coordination in the RuII and RuIII state, respectively. The potentials of the RuIII/II couple differ by about 0.5 V between the isomers, and this results in a bistable electrochemical response of the molecular switches. The effects of structural modifications in form of substituents on the linking carbon atom of the ambidentate ligand and on the central pyridine moiety of the spectator ligand were investigated by electrochemical and computational methods. Differences in isomerization behavior span six orders of magnitude in rate constants and two orders of magnitude in equilibrium constants. The results can be interpreted in terms of steric and electronic substituent effects and their influence on rotational barriers, ligation geometry, and electron deficiency of the metal center.
Molecular Materials with Contrasting Optical Responses from a Single‐Pot Reaction and Fluorescence Switching in a Carbon Acid
Authors: Patra A. , Radhakrishnan T. P.
Published: December 2008

Three for the price of one: The reaction of tetracyanoquinodimethane with an aromatic amine is shown to follow an unusual course leading to three products in a single pot. The product molecules form a family of materials with contrasting optical responses, in that they exhibit light emission of different colors and emission switching that is sensitively triggered by acidic/basic environments (see scheme).

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A wide variety of amines are known to react with 7,7,8,8‐tetracyanoquinodimethane (TCNQ) to yield push–pull diaminodicyanoquinodimethanes with a strongly zwitterionic structure and significant optical and nonlinear optical properties. A novel course of reaction is observed now with the amine 2‐methyl‐4‐chloroaniline, which leads to three well‐defined products, A–C, in a single pot. A and B are formed through the replacement of one cyano group in TCNQ by the amine; A is a carbon acid and B is its corresponding salt. C is the conventional product in which two cyano groups in TCNQ are replaced by the amine. The products are characterized structurally and spectroscopic studies reveal contrasting optical responses. A is nonfluorescent, whereas B and C show red and green emission, respectively, in the solution and solid states. The acid/conjugate‐base pair A and B can be interconverted through facile, reversible, and repeated deprotonation/protonation cycles, which are accompanied by instantaneous switching of the fluorescence. The current study illustrates an interesting case of a single‐pot reaction yielding different optical materials with attributes that can be switched through simple approaches such as protonation or tuned through modification of the push–pull characteristics.
Highly Dense Nitranilates‐Containing Nitrogen‐Rich Cations
Authors: Huang Yangen , Gao Haixiang , Twamley Brendan , Shreeve Jean'ne M.
Published: December 2008

High density energetic salts containing nitrogen‐rich cations and the nitranilic anion were readily synthesized in high yield by metathesis reactions of sodium nitranilate 2 and an appropriate halide. All of the new compounds were fully characterized by elemental, spectral (IR, 1H, 13C NMR), and thermal (DSC) analyses. The structure of hydrazinium nitranilate (4) was also determined by single‐crystal X‐ray analysis. The high symmetry and oxygen content of the anion give these salts extensive hydrogen bonding capability which further results in the high densities, low water solubilities, and high thermal stabilities (Td> 200 °C) of these compounds. Theoretical performance calculations were carried out by using Gaussian 03 and Cheetah 5.0. The calculated detonation pressures (P) for these new salts fall between 17.5 GPa (10) and 31.7 GPa (4), and the detonation velocities (νD) range between 7022 m s−1 (13) and 8638 m s−1 (4).
Computational Investigation of Hydrogen Adsorption by Alkali‐Metal‐Doped Organic Molecules: Role of Aromaticity
Authors: Srinivasu Kancharlapally , Chandrakumar Kuttay R. S. , Ghosh Swapan K.
Published: December 2008

Hydrogen storage: Simple organic molecular systems (CnHn, n=4, 5, 6, 8) are proposed for hydrogen storage purposes based on the concept of aromaticity. The adsorption of hydrogen is attributed to pronounced charge transfer from the sodium atom (green, see picture) to the organic systems and the electrostatic interaction between the ion and hydrogen molecules.

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Theoretical studies on hydrogen adsorption in small organic molecular systems, such as cyclobutadiene (C4H4), the cyclopentadienyl radical (C5H5), benzene (C6H6), and cyclooctatetraene (C8H8) and their metal‐doped modifications, are carried out. Our results reveal that the simple van der Waals surfaces of pure organic molecules are not good enough for hydrogen adsorption due to the weak interaction between hydrogen molecules and the organic molecular surface. However, doping of alkali‐metal atoms in the above organic molecular systems increases their hydrogen adsorption ability significantly, mainly due to electron transfer from the metal atom to the carbon surface. This charged surface created around the metal atom is found to enhance the hydrogen adsorption capacity of the complex considerably, both in terms of interaction energy and the number of adsorbed hydrogen molecules, with a hydrogen adsorption capacity ranging from 10 to 12 wt %. The role of aromaticity in such molecular systems is important in stabilizing these ionized organo‐alkali‐metal complexes.
Efficient and Selective Telomerization of 1,3‐Butadiene with Diols Catalyzed by Palladium–Carbene Complexes
Authors: Grotevendt Anne , Jackstell Ralf , Michalik Dirk , Gomez Mario , Beller Matthias
Published: December 2008

The selective telomerization of 1,3‐butadiene with seven different linear and cyclic diols proceeds in the presence of in situ generated palladium carbene catalysts. By applying optimized reaction conditions, including very low metal loadings (2–10 ppm), excellent catalyst turnover numbers (>250 000) and good chemoselectivities are observed with respect to the mono‐octadienyl ether derivatives. This protocol allows the efficient preparation of unsaturated alcohols, which are useful for various applications.
Imido and Amido Titanium Complexes that Contain a [OSSO]‐Type Bis(phenolato) Ligand: Synthesis, Structures, and Hydroamination Catalysis
Authors: Lian Bing , Spaniol Thomas P. , Horrillo‐Martínez Patricia , Hultzsch Kai C. , Okuda Jun
Published: December 2008

Salt metathesis reaction of the imido complex [Ti(NR)Cl2(NC5H5)3] (R = tBu, C6H3iPr2‐2,6) with 1 equiv. of the lithium salt of the corresponding [OSSO]‐type bis(phenol) [edtbpH2: (HOC6H2‐tBu2‐4,6)2(SCH2CH2S); rac‐(cydtbp)H2: (HOC6H2‐tBu2‐4,6)2(S2C6H10‐1,2)] afforded imido titanium complexes [Ti(edtbp)(NtBu)(NC5H5)] (1), [Ti(edtbp)(NC6H3iPr2‐2,6)(NC5H5)] (2), and [Ti{rac‐(cydtbp)}(NtBu)(NC5H5)] (3). The bis(dimethylamido)titanium complex [Ti(edtbp)(NMe2)2] (4) was synthesized by protonolysis of [Ti(NMe2)4] with bis(phenol) edtbpH2. Reaction of [Ti(NMe2)Cl3] with the lithium salt of the bis(phenol) gave the chloro dimethylamido complex [Ti(edtbp)(NMe2)Cl] (5) in high yield. All complexes were characterized by NMR spectroscopy and elemental analysis. Additionally, complexes 1 and 5 were studied by X‐ray diffraction analysis. Imido titanium complex 1 shows moderate activity in the intramolecular hydroamination reaction of 5‐phenylpent‐4‐ynylamine. Complexes 1–3 catalyze the intramolecular hydroamination of aminoalkenes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)