bluuebunny/crossref_metadata_2025 huggingface dataset:
In Situ Measurement of the Junction Temperature of Light Emitting Diodes Using a Flexible Micro Temperature Sensor
Authors: Lee Chi-Yuan , Su Ay , Liu Yin-Chieh , Fan Wei-Yuan , Hsieh Wei-Jung
Published: June 2009

This investigation aimed to fabricate a flexible micro resistive temperature sensor to measure the junction temperature of a light emitting diode (LED). The junction temperature is typically measured using a thermal resistance measurement approach. This approach is limited in that no standard regulates the timing of data capture. This work presents a micro temperature sensor that can measure temperature stably and continuously, and has the advantages of being lightweight and able to monitor junction temperatures in real time. Micro-electro-mechanical-systems (MEMS) technologies are employed to minimize the size of a temperature sensor that is constructed on a stainless steel foil substrate (SS-304 with 30 μm thickness). A flexible micro resistive temperature sensor can be fixed between the LED chip and the frame. The junction temperature of the LED can be measured from the linear relationship between the temperature and the resistance. The sensitivity of the micro temperature sensor is 0.059 ± 0.004 Ω/°C. The temperature of the commercial CREE® EZ1000 chip is 119.97 °C when it is thermally stable, as measured using the micro temperature sensor; however, it was 126.9 °C, when measured by thermal resistance measurement. The micro temperature sensor can be used to replace thermal resistance measurement and performs reliably.
Applications and Advances in Electronic-Nose Technologies
Authors: Wilson Alphus  D. , Baietto Manuela
Published: June 2009

Electronic-nose devices have received considerable attention in the field of sensor technology during the past twenty years, largely due to the discovery of numerous applications derived from research in diverse fields of applied sciences. Recent applications of electronic nose technologies have come through advances in sensor design, material improvements, software innovations and progress in microcircuitry design and systems integration. The invention of many new e-nose sensor types and arrays, based on different detection principles and mechanisms, is closely correlated with the expansion of new applications. Electronic noses have provided a plethora of benefits to a variety of commercial industries, including the agricultural, biomedical, cosmetics, environmental, food, manufacturing, military, pharmaceutical, regulatory, and various scientific research fields. Advances have improved product attributes, uniformity, and consistency as a result of increases in quality control capabilities afforded by electronic-nose monitoring of all phases of industrial manufacturing processes. This paper is a review of the major electronic-nose technologies, developed since this specialized field was born and became prominent in the mid 1980s, and a summarization of some of the more important and useful applications that have been of greatest benefit to man.
Intuitive and Axiomatic Arguments for Quantifying Diagnostic Test Performance in Units of Information
Authors: Benish W. A.
Published: June 2009

Objectives: Mutual information is a fundamental concept of information theory that quantifies the expected value of the amount of information that diagnostic testing provides about a patient’s disease state. The purpose of this report is to provide both intuitive and axiomatic descriptions of mutual information and, thereby, promote the use of this statistic as a measure of diagnostic test performance.

Methods: We derive the mathematical expression for mutual information from the intuitive assumption that diagnostic information is the average amount that diagnostic testing reduces our surprise upon ultimately learning a patient’s diagnosis. This concept is formalized by defining “surprise” as the surprisal, a function that quantifies the unlikelihood of an event. Mutual information is also shown to be the only function that conforms to a set of axioms which are reasonable requirements of a measure of diagnostic information. These axioms are related to the axioms of information theory used to derive the expression for entropy.

Results: Both approaches to defining mutual information lead to the known relationship that mutual information is equal to the pre-test uncertainty of the disease state minus the expected value of the posttest uncertainty of the disease state. Mutual information also has the property of being additive when a test provides information about independent health problems.

Conclusion: Mutual information is the best single measure of the ability of a diagnostic test to discriminate among the possible disease states.
Computation of a Probabilistic Statistical Shape Model in a Maximum-a-posteriori Framework
Authors: Pennec X. , Ehrhardt J. , Ayache N. , Handels H. , Hufnagel H.
Published: June 2009

Objectives: When analyzing shapes and shape variabilities, the first step is bringing those shapes into correspondence. This is a fundamental problem even when solved by manually determining exact correspondences such as landmarks. We developed a method to represent a mean shape and a variability model for a training data set based on probabilistic correspondence computed between the observations.

Methods: First, the observations are matched on each other with an affine transformation found by the Expectation-Maximization Iterative-Closest-Points (EM-ICP) registration. We then propose a maximum-a-posteriori (MAP) framework in order to compute the statistical shape model (SSM) parameters which result in an optimal adaptation of the model to the observations. The optimization of the MAP explanation is realized with respect to the observation parameters and the generative model parameters in a global criterion and leads to very efficient and closed-form solutions for (almost) all parameters.

Results: We compared our probabilistic SSM to a SSM based on one-to-one correspondences and the PCA (classical SSM). Experiments on synthetic data served to test the performances on non-convex shapes (15 training shapes) which have proved difficult in terms of proper correspondence determination. We then computed the SSMs for real putamen data (21 training shapes). The evaluation was done by measuring the generalization ability as well as the specificity of both SSMs and showed that especially shape detail differences are better modeled by the probabilistic SSM (Hausdorff distance in generalization ability ≈ 25% smaller).

Conclusions: The experimental outcome shows the efficiency and advantages of the new approach as the probabilistic SSM performs better in modeling shape details and differences.
Computer-assisted Diagnosis for Precancerous Lesions in the Esophagus
Authors: Kage A. , Wittenberg T. , Mühldorfer S. , Münzenmayer C.
Published: June 2009

Objectives: The interpretation of endoscopic findings by gastroenterologists is still a difficult and highly subjective task. Despite important developments such as chromo-endoscopy, pit pattern analysis, fluorescence imaging as well as narrow band imaging it still requires lots of experience and training with a certain tentativeness until the final biopsy. By the development of computer-assisted diagnosis (CAD) systems this process can be supported.

Methods: This paper presents a new approach to CAD for precancerous lesions in the esophagus based on color-texture analysis in a content-based image retrieval (CBIR) framework. The novelty of our approach lies in the combination of newly developed color-texture features with the interactive feedback loop provided by a relevance feedback algorithm. This allows the expert to steer the query and is still robust against accidental false decisions.

Results: We reached an inter-rater reliability of κ = 0.71 on a database of 390 endoscopic images. The retrieval accuracy didn’t change significantly until a wrong decision rate of 20%.

Conclusions: Thus, the system could be able to support practitioners with less experience or in private practice. In combination with a connected case database it can also support case-based reasoning for the diagnostic decision process.
Does a fabella-tibial suture alter the outcome for dogs with cranial cruciate ligament insufficiency undergoing arthrotomy and caudal pole medial meniscectomy?
Authors: Comerford E.J. , Owen M.R. , Tivers M.S.
Published: June 2009

Objectives: The objective of this study was to evaluate the effects of fabella-tibial suture (FTS) on long-term outcome in dogs with cranial cruciate ligament (CCL) insufficiency and concurrent medial meniscal tear (MMT) that were managed by an open, caudal pole medial meniscectomy (CPMM).

Methods: A retrospective review was performed of the clinical records of dogs treated for CCL insufficiency with concurrent MMT by open CPMM, with or without the non-random addition of a nylon FTS according to surgeon preference, during the period of 2001 to 2004. The Bristol Osteoarthritis in Dogs questionnaire was modified for owner assessment of outcome using a visual analogue scale based on several criteria: level of activity, disability, severity of lameness and frequency of lameness before and after surgery.

Results: Completed questionnaires from 31 dog owners were received. A FTS was used after CPMM in 22 dogs (FTS group), but in nine dogs (control group) only a CPMM was performed. The median time to follow up was longer in the FTS group (25 months) than the control group (16 months) (P=0.03). There were not any significant differences between the two groups before and after surgery for the following: disability, activity, frequency of lameness, severity of lameness, ability to climb stairs and ability to sit down.

Clinical Significance: The placement of a FTS following stifle joint arthrotomy and CPMM in dogs with CCL deficiency and concurrent MMT may not be a significant factor affecting the ultimate surgical outcome, although our study is limited by the non-randomised study design.
A biomechanical comparison of 3.5 locking compression plate fixation to 3.5 limited contact dynamic compression plate fixation in a canine cadaveric distal humeral metaphyseal gap model
Authors: Lanz O. , McLaughlin R. , Elder S. , Werre S. , Filipowicz D.
Published: June 2009

3.5 locking compression plate (LCP) fixation was compared to 3.5 limited contact dynamic compression plate (LC-DCP) fixation in a canine cadaveric, distal humeral metaphyseal gap model. Thirty paired humeri from adult, large breed dogs were separated into equal groups based on testing: static compression, cyclic compression, and cyclic torsion. Humeral constructs stabilized with LCP were significantly stiffer than those plated with LCDCP when loaded in static axial compression (P = 0.0004). When cyclically loaded in axial compression, the LCP constructs were significantly less stiff than the LC-DCP constructs (P = 0.0029). Constructs plated with LCP were significantly less resistant to torsion over 500 cycles than those plated with LC-DCP (P<0.0001). The increased stiffness of LCP constructs in monotonic loading compared to constructs stabilised with non-locking plates may be attributed to the stability afforded by the plate-screw interface of locking plates. The LCP constructs demonstrated less stiffness in dynamic testing in this model, likely due to plate-bone offset secondary to non-anatomic contouring and occasional incomplete seating of the locking screws when using the torque-limiting screw driver. Resolution of these aspects of LCP application may help improve the stiffness of fixation in fractures modeled by the experimental set-up of this investigation.
Pressure distribution between the deep digital flexor tendon and the navicular bone, and the effect of raising the heels in vitro
Authors: Shaw D.J. , Munaiwa G. , FitzPatrick D.P. , Bellenger C.R. , Weaver M.P.
Published: June 2009

The objectives of this study were to topo-graphically map pressure distribution across the palmar surface of the navicular bone in response to forces applied by the deep digital flexor tendon (DDFT), and evaluate the effect of raising the heels in vitro. A rig was constructed to hold an equine cadaver limb and apply controlled pressure to the navicular bone from the DDFT. Pressure-sensitive paper was used to quantify and map the resultant pressure. Changes in response to heel wedges (5° and 10°) were recorded. The areas subject to maximum pressure from the DDFT were: the central ridge, the paired symmetrical areas adjacent to the ridge and the distal edge of the palmar bone surface. These regions correspond to the known sites of navicular pathology. Heel wedges redistributed the pressure exerted on the palmar surface of the navicular bone, with measurements varying depending on fetlock angle and wedge angle. These in vitro results support the hypothesis that inappropriate forces exerted via the DDFT on the bone cause navicular disease. However, they throw doubt on the practice of shoeing such horses with heel wedges as the redistribution of pressure may increase the force exerted on regions predisposed to disease.
Effect of bending direction on the mechanical behaviour of interlocking nail systems
Authors: Guillou R. P. , Ting D. , Sinnott M. T. , Meyer E. , Haut R. C. , Déjardin L. M.
Published: June 2009

Objectives: To compare the mechanical properties of various interlocking nail constructs in medio-lateral (ML) and cranio-caudal (CC) bending. Methods: Synthetic bone models simulating a severely comminuted tibial fracture were treated with either screwed or bolted, 6 or 8 mm standard interlocking nails (ILN), or an angle-stable ILN (AS-ILN), after which they were then sequentially tested in ML and CC bending. Construct compliance, maximum angular deformation (MaxDef) and slack were statistically compared (p<0.05).

Results: The compliance of all constructs was significantly greater in CC than in ML bending. However, due to the presence of a greater slack in the ML plane, standard ILN constructs sustained significantly more deformation in that plane. Maximum deformation of the novel AS-ILN constructs was the smallest of all constructs and consistently occurred without slack regardless of bending direction. Clinical significance: This study suggested that standard ILN construct overall deformation and acute instability (slack) may be more critical in ML than in CC bending. Conversely, the small MaxDef and the absence of slack in both bending planes seen in novel angle-stable AS-ILN may provide optimal construct stability and in turn may be more conducive to bone healing.
A preliminary retrospective survey of injuries occurring in dogs participating in canine agility
Authors: Hall C. , Trentacosta N. , Percival M. , Levy I.
Published: June 2009

Objectives: Little is known about the risks of injury to dogs participating in the relatively new sport of canine agility. The purpose of this study was to identify the factors that put the participating dog at risk as well as determine the anatomical sites that were most commonly injured.

Methods: A retrospective survey using a paper and web-based data collection instrument was used to evaluate dogs participating in the sport of canine agility.

Results: Of the 1627 dogs included in the study, 33% were injured, and of those 58% were injured in competition. Most injuries occurred on dry outdoor surfaces. Border Collies were the most commonly injured, and injuries were in excess of what would be expected from their exposure. For all dogs, soft tissue injuries were most common. The shoulders and backs of dogs were most commonly injured. Dogs were most commonly injured by contact with an obstacle. The A-frame, dogwalk and bar jump obstacles were responsible for nearly two-thirds of injuries that resulted from contact with the obstacle.

Conclusions: Border Collies are at higher risk for injury than would be expected from their exposure. The A-frame, dogwalk and bar jump obstacles put the shoulders and backs of dogs at risk.

Clinical Relevance: For the first time, this study gives us insight into injuries occurring in dogs participating in canine agility. This will help direct prospective studies that evaluate the safety of individual obstacles, direct rule changes and enable practitioners to understand the risks of the sport.
Does Osgood-Schlatter Disease exist in the dog?
Authors: DeCamp C. E. , Diegel K. L. , Gholve P. A. , Probst C. W. , Déjardin L. M. , Pfeil von
Published: June 2009

Osgood-Schlatter disease (OSD) is a condition affecting human adolescents in which there is partial separation of bone fragments from the tibial tuberosity at the site of insertion of the patellar ligament to the tibial tuberosity. Tensile trauma seems to be the most likely aetiology. Clinical signs in people consist of swelling and pain at the proximal part of the tibial tuberosity and around the distal end of patellar ligament. Radiographs frequently show small ossicles at the patellar ligament insertion. Conservative treatment is usually curative. The term OSD has also been used for the canine patient. However, radiographs of these patients typically show an enlarged radio-lucent line at the apophyseal plate of the tibial tuberosity. This finding is consistent with a mild avulsion fracture of the canine tibial tuberosity. Based on the radiographic differences between the two species, it seems more appropriate to use the term OSD only for people. The purpose of this paper is to review the literature on OSD in people and the reports of injuries to the proximal tibial tuberosity in dogs. In addition, a new classification system for tibial tuberosity avulsion injuries in the immature dog is proposed, with an algorithm for management of this injury.
Surgical approaches for minimally invasive plate osteosynthesis in dogs
Authors: Lewis D. D. , Pozzi A.
Published: June 2009

Fracture stabilisation techniques continue to evolve and to provide approaches which minimise the iatrogenic trauma associated with surgery. Minimally invasive plate osteo-synthesis (MIPO) is a recently described method of biological internal fixation performed by introducing a bone plate via small insertional incisions that are made remote to the fracture site. The plate is slid adjacent to the bone in an epiperiosteal tunnel connecting the two insertional incisions. Screws are placed in the plate through the insertional incisions or via additional stab incisions made over the holes in the plate. In this paper we describe the surgical approaches used to perform MIPO in humeral, radial, fe-moral and tibial fractures in dogs. We found that these approaches allowed safe insertion of the plate without grossly damaging neuro-vascular structures. Further studies are needed to evaluate the clinical outcome of MIPO in dogs.
Feline shoulder arthroscopy using a caudolateral portal, a cadaveric study
Authors: Ridge P.
Published: June 2009

The aim of this cadaveric study was to determine the normal arthroscopic anatomy of the feline shoulder from a caudolateral arthroscope portal, to compare this with the gross anatomy evident upon dissection, and to determine the degree of iatrogenic trauma caused by the arthroscopy. A 1.9 mm, 30° fore oblique arthroscope via a caudolateral portal, and a 21-gauge needle via a cranio-lateral egress portal were used to assess intra-articular structures in eight feline cadaveric shoulders. The medial glenohumeral ligament was shown to be a single banded structure in the craniomedial compartment, and the subscapularis muscle tendon of insertion was visible in all eight shoulders. The biceps brachii tendon and sheath could be examined, although the transverse humeral ligament was not evident arthroscopically from this portal. The lateral glenohumeral ligament was not demonstrated arthroscopically, although a well-defined capsular thickening was present on dissection. No significant neurovascular trauma was evident after arthroscopy.
Traumatic fragmented medial coronoid process in a Chihuahua
Authors: Wheeler J. L. , Manley P. A. , Hadley H. S.
Published: June 2009

Fragmented medial coronoid process (FMCP) is a disease process that has not previously been reported in toy-breed dogs. This report describes a presumptive case of FMCP in a 14-month-old Chihuahua that was presented for evaluation approximately four weeks following acute onset of moderate lameness in the left forelimb. Definitive diagnosis of a fragmented medial coronoid process was based upon computed tomography (CT) scan. A CT scan also demonstrated moderate joint incongruity in the affected elbow. Surgical removal of the fragment and subtotal coronoidectomy were performed via a medial arthrotomy. An ulnar ostectomy was also performed to address joint incongruity. Histology of specimens removed at surgery did not demonstrate evidence of microdamage as characteristic of FMCP in large breed dogs, and instead, suggested that the fracture was acute and traumatic in nature. Rapid return to function was observed following surgery.
Tibial plateau levelling osteotomy in an alpaca
Authors: Girard N. M. , O’Riordan J. , Fitzpatrick N. , Smith T. J.
Published: June 2009

In this report, a case of cranial cruciate ligament (CrCL) rupture treated by tibial plateau levelling osteotomy (TPLO), in a 36-month-old male breeding alpaca, is described. The alpaca was presented with the complaint of acute onset of right pelvic limb lameness. The findings of our clinical and radiographic examinations were consistent with CrCL insufficiency of the right stifle joint. The right tibial plateau angle measured prior to surgery was 19°. A TPLO was performed and this eliminated cranial tibial thrust. Culture of a swab taken from the surgical site prior to wound closure was positive for Pseudomonas aeruginosa. Enrofloxacin was administered parenterally for two weeks postoperatively. There were not any clinical signs of infection noted. Outcome assessments included veterinary examination (two and six weeks) and owner assessment (28 months). At two weeks the animal walked with a grade 2/5 lameness, and at six weeks radiographic examination showed progression of bone healing at the site of tibial osteotomy. A return to full breeding fitness occurred by eight weeks after the surgery. The alpaca remained free from lameness 28 months later, according to the owner.
Appendicular fracture repair in dogs using the locking compression plate system: 47 cases
Authors: Sjöström L. , Devor M. , Haug A. , Haaland P. J.
Published: June 2009

The locking compression plate (LCP) has combination screw holes, making it possible to use the implant in three different ways; as a pure internal fixator using locking head screws, as a conventional compression plate using compression screws, or as a hybrid of the two. The experience with the LCP system in veterinary fracture repair is limited. The objective of this study was to evaluate the outcome of appendicular fractures in dogs, which were repaired with the LCP system combined with less invasive surgical techniques. Medical records and radiographs from 47 dogs were studied retrospectively. Thirty-four percent of the fractures were simple, six percent wedge and 60% comminuted fractures of the humerus (11 %), radius and ulna (30 %), femur (34 %) and of the tibia and fibula (25 %). The fractures were treated using the LCP as an internal fixator; in some cases as a plate and rod construct. Forty-six of 47 fractures reached radiographic union. Mean healing time of the fractures was seven weeks (95% confidence interval from 5.8 to 8.3 weeks). There were statistically significant differences in healing time between juvenile (age under one year) and adults. Complications in the form of implant failures and infections were encountered in approximately 11% of the cases. All implant failures were due to surgical errors. The LCP system in combination with a less invasive surgical approach was found advantageous in comminuted fractures where the LCP was used as a bridging plate, in situations when exact plate contouring was difficult, and when other implants prevented the use of bi-cortical screws.
Giant trochanteric pressure sore: Use of a pedicled chimeric perforator flap for cover
Authors: Mehrotra Sandeep
Published: June 2009

Pressure sores are increasing in frequency commensurate with an ageing population with multi-system disorders and trauma. Numerous classic options are described for providing stable wound cover. With the burgeoning knowledge on perforator anatomy, recent approaches focus on the use of perforator-based flaps in bedsore surgery. A giant neglected trochanteric pressure sore in a paraplegic is presented. Since conventional options of reconstruction appeared remote, the massive ulcer was successfully managed by a chimeric perforator-based flap. The combined muscle and fasciocutaneous flaps were raised as separate paddles based on the anterolateral thigh perforator branches and provided stable cover without complications. Perforators allow versatility in managing complex wounds without compromising on established principles.
Observation of a 2D Electron Gas and the Tuning of the Electrical Conductance of ZnO Nanowires by Controllable Surface Band‐Bending
Authors: Hu Youfan , Liu Yang , Li Wenliang , Gao Min , Liang Xuelei , Li Quan , Peng Lian‐Mao
Published: July 2009

Direct experimental evidence for the existence of a 2D electron gas in devices based on ZnO nanowires (NWs) is presented. A two‐channel core/shell model is proposed for the interpretation of the temperature‐dependent current–voltage (I–V) characteristics of the ZnO NW, where a mixed metallic–semiconducting behavior is observed. The experimental results are quantitatively analyzed using a weak‐localization theory, and suggest that the NW is composed of a “bulk” semiconducting core with a metallic surface accumulation layer, which is basically a 2D electron gas in which the electron–phonon inelastic scattering is much weaker than the electron–electron inelastic scattering. A series of I–V measurements on a single NW device are carried out by alternating the atmosphere (vacuum, H2, vacuum, O2), and a reversible change in the conductance from metallic to semiconducting is achieved, indicating the surface accumulation layer is likely hydroxide‐induced. Such results strongly support the two‐channel model and demonstrate the controllable tuning of the ZnO NW electrical behavior via surface band‐bending.
Alkylzinc‐Mediated Addition of Alkynes to N‐Tosylaldimines: Enantioselective Synthesis of (E)‐(2‐En‐3‐ynyl)‐amines
Authors: Yin Chao , Hu Xiu‐Qin , Hui Xin‐Ping , Xu Peng‐Fei
Published: July 2009

An alkylzinc‐mediated simple and efficient procedure for the catalytic enantioselective synthesis of N‐tosyl‐(E)‐(2‐en‐3‐ynyl)‐amines has been developed. The method works well with various N‐tosylaldimines and alkynes.
Measured occupational solar UVR exposures of lifeguards in pool settings
Authors: Gies Peter , Glanz Karen , O'Riordan David , Elliott Tom , Nehl Eric
Published: July 2009

Background

The aim of this study was to measure ultraviolet radiation (UVR) exposures of lifeguards in pool settings and evaluate their personal UVR protective practices.

Methods

Lifeguards (n = 168) wore UVR sensitive polysulfone (PS) film badges in wrist bracelets on 2 days and completed a survey and diary covering sun protection use. Analyses were used to describe sun exposure and sun protection practices, to compare UVR exposure across locations, and to compare findings with recommended threshold limits for occupational exposure.

Results

The measured UVR exposures varied with location, ranging from high median UVR exposures of 6.2 standard erythemal doses (SEDs) to the lowest median of 1.7 SEDs. More than 74% of the lifeguards' PS badges showed UVR above recommended threshold limits for occupational exposure. Thirty‐nine percent received more than four times the limit and 65% of cases were sufficient to induce sunburn. The most common protective behaviors were wearing sunglasses and using sunscreen, but sun protection was often inadequate.

Conclusions

At‐risk individuals were exposed to high levels of UVR in excess of occupational limits and though appropriate types of sun protection were used, it was not used consistently and more than 50% of lifeguards reported being sunburnt at least twice during the previous year. Am. J. Ind. Med. 52:645–653, 2009. © 2009 Wiley‐Liss, Inc.
Titelbild: A Microfluidic Approach to Chemically Driven Assembly of Colloidal Particles at Gas–Liquid Interfaces (Angew. Chem. 29/2009)
Authors: Park Jai Il , Nie Zhihong , Kumachev Alexander , Abdelrahman Ahmed I. , Binks Bernard P. , Stone Howard A. , Kumacheva Eugenia
Published: July 2009

Chemisch vermittelt werden bei dem von E. Kumacheva et al. in der Zuschrift auf S. 5404 ff. vorgestellten Mikrofluidikansatz partikelbedeckte Bläschen erzeugt. Dabei wird das schnelle und steuerbare Auflösen von CO2‐Bläschen in einer Dispersion carboxylierter Partikel genutzt. Die lokale Erhöhung des pH‐Werts des Mediums in der Nähe der Bläschen bewirkt eine Änderung der Oberflächenenergie der Partikel und ihre Abscheidung an der Gas‐flüssig‐Grenzfläche.

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Epoxide‐Opening Cascades in the Synthesis of Polycyclic Polyether Natural Products
Authors: Vilotijevic Ivan , Jamison Timothy F.
Published: July 2009

The structural featuresof polycyclic polyether natural products can, in some cases, be traced to their biosynthetic origin. However in case that are less well understood, only biosynthetic pathways that feature dramatic, yet speculative, epoxide‐opening cascades are proposed. We summarize how such epoxide‐opening cascade reactions have been used in the synthesis of polycyclic polyethers (see scheme) and related natural products.

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The group of polycyclic polyether natural products is of special interest owing to the fascinating structure and biological effects displayed by its members. The latter includes potentially therapeutic antibiotic, antifungal, and anticancer properties, and extreme lethality. The polycyclic structural features of this class of compounds can, in some cases, be traced to their biosynthetic origin, but in others that are less well understood, only to proposed biosynthetic pathways that feature dramatic, yet speculative, epoxide‐opening cascades. In this review we summarize how such epoxide‐opening cascade reactions have been used in the synthesis of polycyclic polyethers and related natural products.
Separation of oil and carotenes from palm oil mill effluent by adsorption chromatography with silica based adsorbent
Authors: Ahmad A. L. , Chan C. Y. , Abd Shukor S. R. , Mashitah M. D.
Published: July 2009

Malaysia is an agricultural country and the major polluting industrial effluents have been from palm oil industry. Palm oil mill effluent (POME) is a liquid waste which causes a significant impact on the environment if it is not dealt properly. POME contains oil and carotenes that need to be treated before discharge. Owing to the readily available source of POME and growing demand of carotenes, the objective of this paper is to recover the carotenes from POME whilst tackling the environmental problem. In this study, solvent extraction is used to retrieve oil from POME and adsorption chromatography is further adopted to recover the carotenes contained in the oil. Residual oil extracted from POME in this study was about 5000 mg/L in a single stage solvent extraction. The carotenes content in recovered oil was about 450 ppm. Synthetic adsorbent with silica based material was used in the adsorption chromatography. Carotenes was concentrated to about 25 times of the concentration in the recovered oil by adsorption chromatography. Carotenes recovery was found to be depended on the process conditions. Different types of solvent, column temperatures and initial loading volumes were evaluated to determine the effects on the percentage of carotenes extracted and carotenes concentration. The suitable temperature for adsorption process was 40 °C. Carotenes was successfully concentrated from the recovered oil by adsorption chromatography process. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.
Developing a new collection‐evaluation method: Mapping and the user‐side h‐index
Authors: Kim Pan Jun , Lee Jae Yun , Park Ji‐Hong
Published: July 2009

This study proposes a new visualization method and index for collection evaluation. Specifically, it develops a network‐based mapping technique and a user‐focused Hirsch index (user‐side h‐index) given the lack of previous studies on collection evaluation methods that have used the h‐index. A user‐side h‐index is developed and compared with previous indices (use factor, difference of percentages, collection‐side h‐index) that represent the strengths of the subject classes of a library collection. The mapping procedure includes the subject‐usage profiling of 63 subject classes and collection‐usage map generations through the pathfinder network algorithm. Cluster analyses are then conducted upon the pathfinder network to generate 5 large and 14 small clusters. The nodes represent the strengths of the subject‐class usages reflected by the user‐side h‐index. The user‐side h‐index was found to have advantages (e.g., better demonstrating the real utility of each subject class) over the other indices. It also can more clearly distinguish the strengths between the subject classes than can collection‐side h‐index. These results may help to identify actual usage and strengths of subject classes in library collections through visualized maps. This may be a useful rationale for the establishment of the collection‐development plan.
Ge Pairs and Sb Ribbons in Rare‐Earth Germanium Antimonides RE12Ge7−xSb21 (RE=La–Pr)
Authors: Bie Haiying , Mar Arthur
Published: July 2009

The ternary rare‐earth germanium antimonides RE12Ge7−xSb21 (RE=La–Pr; x=0.4–0.5) are synthesized by direct reactions of the elements. Single‐crystal X‐ray diffraction studies indicate that they adopt a new structure type (space group Immm, Z=2, a=4.3165(4)–4.2578(2) Å, b=15.2050(12)–14.9777(7) Å, c=34.443(3)–33.9376(16) Å in the progression from RE=La to Pr), integrating complex features found in RE6Ge5−xSb11+x and RE12Ga4Sb23. A three‐dimensional polyanionic framework, consisting of Ge pairs and Sb ribbons, outlines large channels occupied by columns of face‐sharing RE6 trigonal prisms. These trigonal prisms are centered by additional Ge and Sb atoms to form GeSb3 trigonal‐planar units. A bonding analysis attempted through a Zintl–Klemm approach suggests that full electron transfer from the RE atoms to the anionic substructure cannot be assumed. This is confirmed by band‐structure calculations, which also reveal the importance of GeSb and SbSb bonding. Magnetic measurements on Ce12Ge6.5Sb21 indicate antiferromagnetic coupling but no long‐range ordering down to 2 K.
A Zwitterionic Silylene as Reactive Intermediate and Its Unusual Dimerization to an N‐Heterobicyclic Disilane
Authors: Xiong Yun , Yao Shenglai , Driess Matthias
Published: July 2009

A way to synthesize the transient zwitterionic silylene L′Si: 8 {L’=CH[(C=CH2)CMe(N(tBu))2]} and achieve its facile dimerization to the remarkable N‐heterobicyclic disilane 82 is described. At first, employing the β‐diketiminate ligand L [L=CH(CMeN(tBu))2], both starting materials LH (2) and its N‐lithium salt LLi (3) can react with SiBr4 to yield the silylene precursor L′SiBr2 (4) by silicon‐induced CH activation at an exocyclic methyl group on the backbone of the ligand. Compound 4 reacts with SiBr4 above room temperature to afford the unexpected terminal CH(SiBr3)‐substituted dibromosilane 6 along with the unique tricyclic trisilane 7. Reduction of 4 with KC8 at 0 °C furnishes the novel N‐heterobicyclic disilane 82, which is a formal dimer of the desired zwitterionic silylene L′Si: (8). It has been reasoned that compound 82 may results from [4+1] cycloaddition of two molecules of 8 to give the transient dimer 82′, which subsequently undergoes hydrogen transfer from a terminal methyl group on the backbone of the C3N2Si ligand to the low‐coordinate Si atom. The latter dimerization can be rationalized by the intrinsic zwitterionic character of 8 and insufficient steric protection through the tBu groups at the nitrogen atoms. The novel compounds 3, 4, 6, 7, and 82 have been characterized by 1H, 13C, and 29Si NMR spectroscopy, mass spectrometry, and elemental analysis. Additionally, the structures of 3, 6, 7, and 82 were also established by single‐crystal X‐ray diffraction analyses.
Relative Stability of closo‐closo, closo‐nido, and nido‐nido Macropolyhedral Boranes: The Role of Orbital Compatibility
Authors: Shameema Oottikkal , Jemmis Eluvathingal D.
Published: July 2009

The concept of orbital compatibility is used to explain the relative energies of different macropolyhedral structural patterns such as closo‐closo, closo‐nido, and nido‐nido. A large polyhedral borane condenses preferentially with a smaller polyhedron owing to orbital compatibility. Calculations carried out at the B3LYP/6‐31G* level show that the macropolyhedron closo(12)‐closo(6) is the most preferred structural pattern among the face‐sharing closo‐closo systems. The relative stabilities of four‐shared‐atom closo‐closo, three‐shared‐atom closo‐closo, three‐shared‐atom closo‐nido, edge‐sharing closo‐nido, and edge‐sharing nido‐nido structures are in accordance with the difference in the number of vertices of the individual polyhedra of the macropolyhedra. When the difference in the number of vertices of the individual polyhedra is large, the stability of the macropolyhedra is also large. Calculations further show that the orbital compatibility plays an important role in deciding the stability of the macropolyhedral boranes with more than two polyhedral units. The dependence of the orbital compatibility on the relative stability of the macropolyhedron varies with other factors such as inherent stability of the individual polyhedron and steric factors.
Toward an in situ phospho‐protein atlas: phospho‐ and site‐specific antibody‐based spatio‐temporally systematized detection of phosphorylated proteins in vivo
Authors: Teraishi Toshiya , Miura Kenji
Published: July 2009

The “Human Genome Project” was completed in 2003, shifting the focus to proteome and transcriptome research. One approach to proteomics involves the comprehensive visualization of the localization of proteins in all tissues and organs. We discuss in situ phospho‐protein atlases, which are systematized representations of the localization of proteins. Protein atlases provide important information about the identity and presence of proteins in specific organs, tissues and cells under physiological and pathological conditions. Antibody‐based immunohistochemical analysis is a powerful method for generating a protein atlas. However, it is difficult to localize phosphorylated proteins under in vivo physiological conditions, even with immunohistochemistry, because these proteins tend to be dephosphorylated or phosphorylated due to the experimental manipulations. We also discuss an improved immunohistochemical method for precisely detecting phosphorylated protein, using the detection of phosphorylated ERK1/2 as an example. We consider that it is possible and useful to generate a phospho‐protein atlas.
Synthesis of the long‐persistence phosphor CaAl2O4:Eu2+, Dy3+, Nd3+ by combustion method and its luminescent properties
Authors: Zhang Bo , Zhao Changliang , Chen Donghua
Published: July 2009

Calcium aluminate phosphor co‐doped Eu2+, Dy3+, Nd3+ is prepared by the combustion method. We study systemically the influences of the quantity of mixed Dy3+ ion, the quantity of flux H3BO3, the differences in dispersing methods between magnetic stirring and ultrasonic dispersing and the combustion temperature on the long‐persistence phosphor. The analytical results indicate that Dy3+ ion improves the properties of the phosphors CaAl2O4:Eu2+, Nd3+. The appropriate quantity of flux H3BO3 to reduce the forming temperature of the sample was determined. The monoclinic single phase of CaAl2O4 formed at 500°C and remained steady. The calcium aluminate co‐doped Eu2+, Dy3+, Nd3+ was synthesized by dispersal of the raw material using the ultrasonic method, and it had better optical properties. Copyright © 2009 John Wiley & Sons, Ltd.
Metabolism in 1,3‐propanediol fed‐batch fermentation by a D‐lactate deficient mutant of Klebsiella pneumoniae
Authors: Xu Yun‐Zhen , Guo Ni‐Ni , Zheng Zong‐Ming , Ou Xian‐Jin , Liu Hong‐Juan , Liu De‐Hua
Published: July 2009

Klebsiella pneumoniae HR526, a new isolated 1,3‐propanediol (1,3‐PD) producer, exhibited great productivity. However, the accumulation of lactate in the late‐exponential phase remained an obstacle of 1,3‐PD industrial scale production. Hereby, mutants lacking D‐lactate pathway were constructed by knocking out the ldhA gene encoding fermentative D‐lactate dehydrogenase (LDH) of HR526. The mutant K. pneumoniae LDH526 with the lowest LDH activity was studied in aerobic fed‐batch fermentation. In experiments using pure glycerol as feedstock, the 1,3‐PD concentrations, conversion, and productivity increased from 95.39 g L−1, 0.48 and 1.98 g L−1 h−1 to 102. 06 g L−1, 0.52 mol mol−1 and 2.13 g L−1 h−1, respectively. The diol (1,3‐PD and 2,3‐butanediol) conversion increased from 0.55 mol mol−1 to a maximum of 0.65 mol mol−1. Lactate would not accumulate until 1,3‐PD exceeded 84 g L−1, and the final lactate concentration decreased dramatically from more than 40 g L−1 to <3 g L−1. Enzymic measurements showed LDH activity decreased by 89–98% during fed‐batch fermentation, and other related enzyme activities were not affected. NADH/NAD+ enhanced more than 50% in the late‐exponential phase as the D‐lactate pathway was cut off, which might be the main reason for the change of final metabolites concentrations. The ability to utilize crude glycerol from biodiesel process and great genetic stability demonstrated that K. pnemoniae LDH526 was valuable for 1,3‐PD industrial production. Biotechnol. Bioeng. 2009; 104: 965–972. © 2009 Wiley Periodicals, Inc.
Simultaneous determination of eight major steroids from Polyporus umbellatus by high‐performance liquid chromatography coupled with mass spectrometry detections
Authors: Zhao Ying‐yong , Cheng Xian‐long , Zhang Yongmin , Zhao Ye , Lin Rui‐chao , Sun Wen‐ji
Published: July 2009

Polyporus umbellatus is a widely used diuretic herbal medicine. In this study, a high‐performance liquid chromatography coupled with atmospheric pressure chemical ionization–mass spectrometric detection (HPLC‐APCI‐MS) method was developed for qualitative and quantitative analysis of steroids, as well as for the quality control of Polyporus umbellatus. The selectivity, reproducibility and sensitivity were compared with HPLC with photodiode array detection and evaporative light scattering detection (ELSD). Selective ion monitoring in positive mode was used for qualitative and quantitative analysis of eight major components and β‐ecdysterone was used as the internal standard. Limits of detection and quantification fell in the ranges 7–21 and 18–63 ng/mL for the eight analytes with an injection of 10 µL samples, and all calibration curves showed good linear regression (r2 > 0.9919) within the test range. The quantitative results demonstrated that samples from different localities showed different qualities. Advantages, in comparison with conventional HPLC–diode array detection and HPLC‐ELSD, are that reliable identification of target compounds could be achieved by accurate mass measurements along with characteristic retention time, and the great enhancement in selectivity and sensitivity allows identification and quantification of low levels of constituents in complex Polyporus umbellatus matrixes. Copyright © 2009 John Wiley & Sons, Ltd.
Who succeeds in jail diversion programs for persons with mental illness? A multi‐site study
Authors: Case Brian , Steadman Henry J. , Dupuis Seth A. , Morris Laura S.
Published: July 2009

This study examined how the characteristics of people with mental illness who are participants in post‐booking jail diversion programs affect recidivism and time spent incarcerated. The study employed data from a multi‐site, federally funded jail diversion initiative. A pre–post comparison design was used to compare experiences of arrest and days spent in jail of diverted individuals for the 12 months following enrollment with the 12 months prior to enrollment. Also compared were differences in 12‐month public safety outcomes. Data were collected between February 2003 and August 2007. The findings suggest that people with mental illness who are diverted from jail to community‐based services experience fewer arrests and jail days. Approximately half of the sample were never arrested during the 12 months following enrollment. The strongest differences between people who experienced reduced contact with the criminal justice system and people with unchanged or increased contact were found in measures of criminal history. The results suggest that services targeted to diverted individuals with mental illness should address public safety goals, not just those of public health. Copyright © 2009 John Wiley & Sons, Ltd.
Optimization of chimeric HIV‐1 virus‐like particle production in a baculovirus‐insect cell expression system
Authors: Pillay Sirika , Meyers Ann , Williamson Anna‐Lise , Rybicki Edward P.
Published: July 2009

A baculovirus‐insect cell expression system potentially provides the means to produce prophylactic HIV‐1 virus‐like particle (VLP) vaccines inexpensively and in large quantities. However, the system must be optimized to maximize yields and increase process efficiency. In this study, we optimized the production of two novel, chimeric HIV‐1 VLP vaccine candidates (GagRT and GagTN) in insect cells. This was done by monitoring the effects of four specific factors on VLP expression: these were insect cell line, cell density, multiplicity of infection (MOI), and infection time. The use of western blots, Gag p24 ELISA, and four‐factorial ANOVA allowed the determination of the most favorable conditions for chimeric VLP production, as well as which factors affected VLP expression most significantly. Both VLP vaccine candidates favored similar optimal conditions, demonstrating higher yields of VLPs when produced in the Trichoplusia ni Pro™ insect cell line, at a cell density of 1 × 106 cells/mL, and an infection time of 96 h post infection. It was found that cell density and infection time were major influencing factors, but that MOI did not affect VLP expression significantly. This work provides a potentially valuable guideline for HIV‐1 protein vaccine optimization, as well as for general optimization of a baculovirus‐based expression system to produce complex recombinant proteins. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Multiobjective flux balancing using the NISE method for metabolic network analysis
Authors: Oh Young‐Gyun , Lee Dong‐Yup , Lee Sang Yup , Park Sunwon
Published: July 2009

Flux balance analysis (FBA) is well acknowledged as an analysis tool of metabolic networks in the framework of metabolic engineering. However, FBA has a limitation for solving a multiobjective optimization problem which considers multiple conflicting objectives. In this study, we propose a novel multiobjective flux balance analysis method, which adapts the noninferior set estimation (NISE) method (Solanki et al., 1993) for multiobjective linear programming (MOLP) problems. NISE method can generate an approximation of the Pareto curve for conflicting objectives without redundant iterations of single objective optimization. Furthermore, the flux distributions at each Pareto optimal solution can be obtained for understanding the internal flux changes in the metabolic network. The functionality of this approach is shown by applying it to a genome‐scale in silico model of E. coli. Multiple objectives for the poly(3‐hydroxybutyrate) [P(3HB)] production are considered simultaneously, and relationships among them are identified. The Pareto curve for maximizing succinic acid production vs. maximizing biomass production is used for the in silico analysis of various combinatorial knockout strains. This proposed method accelerates the strain improvement in the metabolic engineering by reducing computation time of obtaining the Pareto curve and analysis time of flux distribution at each Pareto optimal solution. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009