bluuebunny/crossref_metadata_2025 huggingface dataset:
Nordihydroguaiaretic acid inhibits insulin‐like growth factor signaling, growth, and survival in human neuroblastoma cells
Authors: Meyer Gary E. , Chesler Louis , Liu Dandan , Gable Karissa , Maddux Betty A. , Goldenberg David D. , Youngren Jack F. , Goldfine Ira D. , Weiss William A. , Matthay Katherine K. , Rosenthal Stephen M.
Published: May 2007

Neuroblastoma is a common pediatric malignancy that metastasizes to the liver, bone, and other organs. Children with metastatic disease have a less than 50% chance of survival with current treatments. Insulin‐like growth factors (IGFs) stimulate neuroblastoma growth, survival, and motility, and are expressed by neuroblastoma cells and the tissues they invade. Thus, therapies that disrupt the effects of IGFs on neuroblastoma tumorigenesis may slow disease progression. We show that NVP‐AEW541, a specific inhibitor of the IGF‐I receptor (IGF‐IR), potently inhibits neuroblastoma growth in vitro. Nordihydroguaiaretic acid (NDGA), a phenolic compound isolated from the creosote bush (Larrea divaricata), has anti‐tumor properties against a number of malignancies, has been shown to inhibit the phosphorylation and activation of the IGF‐IR in breast cancer cells, and is currently in Phase I trials for prostate cancer. In the present study in neuroblastoma, NDGA inhibits IGF‐I‐mediated activation of the IGF‐IR and disrupts activation of ERK and Akt signaling pathways induced by IGF‐I. NDGA inhibits growth of neuroblastoma cells and induces apoptosis at higher doses, causing IGF‐I‐resistant activation of caspase‐3 and a large increase in the fraction of sub‐G0 cells. In addition, NDGA inhibits the growth of xenografted human neuroblastoma tumors in nude mice. These results indicate that NDGA may be useful in the treatment of neuroblastoma and may function in part via disruption of IGF‐IR signaling. J. Cell. Biochem. 102: 1529–1541, 2007. © 2007 Wiley‐Liss, Inc.
Reduction of PKCα decreases cell proliferation, migration, and invasion of human malignant hepatocellular carcinoma
Authors: Wu Trang‐Tiau , Hsieh Yi‐Hsien , Hsieh Yih‐Shou , Liu Jer‐Yuh
Published: May 2007

Protein kinase C (PKC) superfamily play key regulatory roles on the development of cancer. However, the exact role of these enzymes in human hepatocellular carcinoma (HCC) has not been well established. Using the RT‐PCR and Western blotting to analyze the levels of PKC isoforms mRNA and protein in the five different differentiated hepatoma cell lines, we found that PKCα was highly expressed in the poor‐differentiated HCC cell lines (SK‐Hep‐1 and HA22T/VGH) as compared with that in the well‐differentiated HCC cell lines (PLC/PRF/5, Hep3B, and HepG2). When treated with PKCα antisense oligonucleotides (ODN), both HA22T/VGH and SK‐Hep‐1 cells lines showed the reduction of PKCα expression, as well as a deceleration in the growth rate and in the level of cyclin D1, but the increase in the levels of p53 and p21WAF1/CIP1. Moreover, the reduction of PKCα expression also inhibited the migratory and invasive potential of both HA22T/VGH and SK‐Hep‐1 cells lines, and revealed a down‐regulation of several migration/invasion‐related genes (MMP‐1, u‐PA, u‐PAR, and FAK). These phenomenon were also confirmed by DNA‐based small interfering RNA (siRNA) PKCα and PKCα/β specific inhibitor Go6976. Thus, the results indicated that PKCα may be associated with regulation of cell proliferation/migration/invasion in human poorly differentiated HCC cells, suggesting a role for the PKCα in the malignant progression of human HCC. J. Cell. Biochem. 103: 9–20, 2008. © 2007 Wiley‐Liss, Inc.
Spontaneous rupture with pseudoaneurysm formation in a nodular goiter presenting as a large neck mass
Authors: Chang Chia‐Che , Chou Yi‐Hong , Tiu Chui‐Mei , Chiou Hong‐Jen , Wang Hsin‐Kai , Chiou See‐Ying , Chen Siew‐Peng , Chang Ming‐Wei , Chang Chi‐Houng , Hong Ting‐Han
Published: May 2007

Acute airway obstruction caused by goiter hemorrhage is a rare but potentially life‐threatening condition. We report a case of nodular goiter in which spontaneous rupture with active bleeding developed suddenly, presenting as a large neck mass with dyspnea. Sonographic examination revealed a large inhomogeneous soft tissue mass in the left thyroid lobe containing some hypoechoic areas. Color Doppler and spectral Doppler analysis were consistent with a large hematoma and pseudoaneurysm, which was subsequently confirmed at surgery. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2007
Thromboembolic complications of left ventricular noncompaction: Case report and brief review of the literature
Authors: Pitta Sridevi , Thatai Deepak , Afonso Luis
Published: May 2007

Left ventricular noncompaction (LVNC) is a rare condition that is believed to represent an arrest in endomyocardial morphogenesis. This entity may be complicated by the development of mural thrombi and embolic events, however data on the associated thromboembolic risk is variable and poorly defined. We describe 2 cases of LVNC in African American patients presenting with thromboembolic manifestations and briefly review the available literature relevant to this complication. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2007
Value of ultrasound‐guided core biopsy in the diagnosis of malignant lymphoma
Authors: de Larrinoa Aitor Fernández , del Cura Jose , Zabala Rosa , Fuertes Elena , Bilbao Francisco , Lopez Jose I.
Published: May 2007

Purpose.

Ultrasound‐guided core needle biopsy for the diagnosis and management of malignant lymphomas is controversial and has not been accepted as an alternative to surgical biopsy. We investigate the clinical usefulness of this procedure in a large series of patients.

Methods.

Over a 5‐year period (2000–2004), ultrasound‐guided core needle biopsies were performed in 102 malignant lymphomas. Five diagnostic categories were considered: large B‐cell lymphomas (LBCL), small B‐cell lymphomas (SBCL), Hodgkin's disease (HD), T cell lymphomas, and miscellaneous. Surgical excisional biopsy of the node was performed in 47 cases (46.1%) for diagnostic confirmation.

Results.

The overall diagnostic accuracy of ultrasound‐guided core needle biopsy was 88.2% (90/102). SBCL (39), LBCL (36), HD (15), T cell lymphomas (5), and miscellaneous (7) [including T cell–rich B cell (2), natural killer cell (1), Burkitt's lymphoma (1), and non‐Hodgkin's lymphoma of the B cell type, NOS (3)] were correctly diagnosed. Three HDs, 1 natural killer cell lymphoma, 1 follicular lymphoma, and 1 LBCL were not correctly diagnosed. The core needle biopsy did not yield tumor tissue in 6 cases.

Conclusions.

Ultrasound‐guided core needle biopsy is effective in the diagnosis of malignant lymphomas and can be used as the first diagnostic approach in selected clinical situations. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2007
Three‐dimensional clavicular and acromioclavicular rotations during arm abduction using vertically open MRI
Authors: Sahara Wataru , Sugamoto Kazuomi , Murai Masakazu , Yoshikawa Hideki
Published: May 2007

There have been several reports about the clavicular and acromioclavicular motion, but a precise motion has been unknown. The purpose of this study was to analyze the 3D kinematics of the clavicle and acromioclavicular joint during arm abduction, using 3D MR images obtained by a vertically open MRI. Seven subjects participated in this investigation, which included 14 shoulders. From a seated position, we obtained MR images of their shoulder in seven abducted positions of the arm in the coronal plane. We evaluated the 3D movements of each bone in the shoulder using the volume‐based registration technique, and analyzed the clavicular positions relative to the lung and the scapular positions relative to the clavicle. During arm abduction, the clavicular motion relative to the lung showed 30.6° retraction, 7.3° elevation, and 33.2° posterior axial rotation. During arm abduction, the scapular motion relative to the clavicle showed 15.6° protraction, 21.5° upward rotation, and 22.2° posterior tilting. This study succeeded in describing the 3D clavicular and acromioclavicular motion including the axial rotation of the clavicle, and it revealed that both motions had large degrees of rotations. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1243–1249, 2007
The Rb family connects with the Tp53 family in skin carcinogenesis
Authors: Lara María Fernanda , Paramio Jesús M.
Published: May 2007

In contrast with the low frequency of alterations found in the Rb gene, the pRb pathway is inactivated in the vast majority of human tumors. A similar situation takes place in mouse models of cancer, including two‐stage skin tumorigenesis. This might be explained if the Rb functions are carried out, in its absence, by other proteins that are also controlled by the same upstream regulators and display similar effectors. The other Rb family members, p107 and or p130, are plausible candidates. The embryonic lethality of pRb‐deficient animals, which precludes the analysis of the roles of Rb gene in mouse models, has been avoided using tissue‐specific deletion of pRb. In epidermis, pRb deletion leads to altered proliferation and differentiation. However, these deficient mice do not develop spontaneous tumors, and chemical carcinogenesis experiments revealed that the absence of pRb renders fewer and smaller tumors than control animals, but showing increased malignant conversion to squamous cell carcinomas (SCC). Detailed biochemical analyses have indicated that, in the absence of pRb, multiple pathways, including the aberrant p53 activation mediated by E2F/p19ARF, are activated leading to increased tumor apoptosis. As Rb loss in epidermis is functionally compensated by Rbl1 (p107), this might also suggest that p107 could behave as a tumor suppressor. We summarize here our findings in support of this hypothesis. The pRb−;p107−/− epidermis form spontaneous tumors, and the reduction of p107 levels restores the susceptibility of pRb‐mice to chemical skin carcinogenesis experiments. Moreover, Rb‐deficient keratinocytes are highly susceptible to Ha‐ras‐induced transformation, and this susceptibility is enhanced by p107 loss. Further functional studies have indicated that the loss of p107 in the absence of pRb produces the reduction of p53‐dependent proapoptotic signals through the modulation of p63 and p73 isoforms. In addition, expression profiling analysis has revealed multiple oncogenic alterations that can contribute to tumor susceptibility in epidermis in the absence of pRb and p107. © 2007 Wiley‐Liss, Inc.
Is there seasonal variation in risk of Parkinson's disease?
Authors: Postuma Ronald B. , Wolfson Christina , Rajput Ali , Stoessl A. Jon , Martin W.R. Wayne , Suchowersky Oksana , Chouinard Sylvain , Panisset Michel , Jog Mandar S. , Grimes David A. , Marras Connie , Lang Anthony E.
Published: May 2007

Recent studies suggest that, for many adult‐onset neurological diseases, persons born at a certain time of year are at higher risk of the disease. Small‐scale studies have suggested that persons born in the spring may be at higher risk of developing Parkinson's disease (PD) late in life. There have also been suggestions that there are clusters of PD birth dates in the years of major influenza pandemics. To determine whether there is any seasonal variation in the birth dates of PD patients, we examined birth dates of 8,168 PD patients collected from subspecialty movement disorder clinics across Canada. Patterns of seasonality of birth were examined and compared with the general Canadian population. In addition, we compared counts of patients born in the years of major influenza pandemics with the number born in the surrounding years. We found no evidence of systematic seasonal variation in PD incidence by birth date, or of clustering of birth dates during influenza pandemic years in PD patients. © 2006 Movement Disorder Society
Role of DAT‐SPECT in the diagnostic work up of Parkinsonism
Authors: Scherfler Christoph , Schwarz Johannes , Antonini Angelo , Grosset Donald , Valldeoriola Francesc , Marek Kenneth , Oertel Wolfgang , Tolosa Eduardo , Lees Andrew J. , Poewe Werner
Published: May 2007

The diagnosis of idiopathic Parkinson's disease (PD) can be achieved with high degrees of accuracy in cases with full expression of classical clinical features. However, diagnostic uncertainty remains in early disease with subtle or ambiguous signs. Functional imaging has been suggested to increase the diagnostic yield in parkinsonian syndromes with uncertain clinical classification. Loss of striatal dopamine nerve terminal function, a hallmark of neurodegenerative Parkinsonism, is strongly related to decreases of dopamine transporter (DAT) density, which can be measured by single photon emission computed tomography (SPECT). The use of DAT‐SPECT facilitates the differential diagnosis in patients with isolated tremor symptoms not fulfilling PD or essential tremor criteria, drug‐induced, psychogenic and vascular Parkinsonism as well as dementia when associated with Parkinsonism. This review addresses the value of DAT‐SPECT in early differential diagnosis, and its potential as a screening tool for subjects at risk of developing PD as well as issues around the assessment of disease progression. © 2007 Movement Disorder Society
Relevance of glycosylation of human zona pellucida glycoproteins for their binding to capacitated human spermatozoa and subsequent induction of acrosomal exocytosis
Authors: Chakravarty S. , Kadunganattil S. , Bansal P. , Sharma R.K. , Gupta S.K.
Published: May 2007

To delineate the functional aspects of zona pellucida (ZP) glycoproteins during fertilization in human, in the present study, fluorochrome‐conjugated Escherichia coli (E. coli)‐ and baculovirus‐expressed recombinant human ZP glycoprotein‐2 (ZP2), ‐3 (ZP3), and ‐4 (ZP4) were employed. In an immunofluorescence assay, capacitated human sperm exhibited binding of the baculovirus‐expressed recombinant ZP3 as well as ZP4 to either acrosomal cap or equatorial region whereas acrosome‐reacted sperm failed to show any binding to the acrosomal cap. Using double labeling experiments, simultaneous binding of ZP3 and ZP4 to the acrosomal cap was observed suggesting the possibility of different binding sites of these proteins on the sperm surface. No binding of ZP2 was observed to the capacitated sperm. However, acrosome‐reacted sperm (20.00 ± 1.93%) showed binding of ZP2 that was restricted to only equatorial region. Interestingly, E. coli‐expressed recombinant human zona proteins also showed very similar binding profiles. Competitive inhibition studies with unlabeled recombinant human zona proteins revealed the specificity of the above binding characteristics. Binding characteristics have been further validated by an indirect immunofluorescence assay using native human heat solubilized isolated zona pellucida. Employing baculovirus‐expressed recombinant ZP3 and ZP4 with reduced N‐linked glycosylation and respective E. coli‐expressed recombinant proteins, it was observed that glycosylation is required for induction of acrosomal exocytosis but its absence may not compromise on their binding ability. These studies have revealed the binding profile of individual human zona protein to spermatozoa and further strengthened the importance of glycosylation of zona proteins for acrosomal exocytosis in spermatozoa. Mol. Reprod. Dev. 75: 75–88, 2008. © 2007 Wiley‐Liss, Inc.
Effects of gonadotrophins, growth hormone, and activin A on enzymatically isolated follicle growth, oocyte chromatin organization, and steroid secretion
Authors: Ola Safiriyu Idowu , Ai Jun‐Shu , Liu Jing‐He , Wang Qiang , Wang Zhen‐Bo , Chen Da‐Yuan , Sun Qing‐Yuan
Published: May 2007

So far, standard follicle culture systems can produce blastocyst from less than 40% of the in vitro matured oocytes compared to over 70% in the in vivo counterpart. Because the capacity for embryonic development is strictly associated with the terminal stage of oocyte growth, the nuclear maturity status of the in vitro grown oocyte was the subject of this study. Mouse early preantral follicles (100–130 µm) and early antral follicles (170–200 µm) isolated enzymatically were cultured for 12 and 4 days, respectively, in a collagen‐free dish. The serum‐based media were supplemented with either 100 mIU/ml FSH (FSH only); 100 mIU/ml FSH + 10 mIU/ml LH (FSH‐LH); 100 mIU/ml FSH + 1 mIU/ml GH (FSH‐GH) or 100 mIU/ml FSH + 100 ng/ml activin A (FSH‐AA). Follicle survival was highest in follicle stimulating hormone (FSH)‐AA group in both cultured preantral (91.8%) and antral follicles (82.7%). Survival rates in the other groups ranged between 48% (FSH only, preantral follicle culture) and 78.7% (FSH only, antral follicle culture). Estradiol and progesterone were undetectable in medium lacking gonadotrophins while AA supplementation in synergy with FSH caused increased estradiol secretion and a simultaneously lowered progesterone secretion. Chromatin configuration of oocytes from surviving follicles at the end of culture revealed that there were twice more developmentally incompetent non‐surrounded nucleolus (NSN) oocytes (>65%) than the competent surrounded nucleolus (SN) oocytes (<34%). We conclude that the present standard follicle culture system does not produce optimum proportion of developmentally competent oocytes. Mol. Reprod. Dev. 75: 89–96, 2008. © 2007 Wiley‐Liss, Inc.
Cerebral involvement in myotonic dystrophies
Authors: Meola Giovanni , Sansone Valeria
Published: May 2007

Myotonic dystrophy types 1 (DM1) and 2 (DM2) are similar yet distinct autosomal‐dominant disorders characterized by muscle weakness, myotonia, cataracts, and multiple organ involvement, including the brain. One key difference between DM1 and DM2 is that a congenital form has been described for DM1 only. Expression of RNA transcripts containing pathogenic repeat lengths produces defects in alternative splicing of multiple RNAs, sequesters specific repeat‐binding proteins, and ultimately leads to developmentally inappropriate splice products for a particular tissue. Whether brain pathology in its entirety in adult DM1 and DM2 is caused by interference in RNA processing remains to be determined. This review focuses on the similarities and differences between DM1 and DM2 with respect to neuropsychological, neuropathological, and neuroimaging data relating to cerebral involvement, with special emphasis on the clinical relevance and social consequences of such involvement. Muscle Nerve, 2007
Velocity recovery function of the compound muscle action potential assessed with doublet and triplet stimulation
Authors: Kamavuako Ernest Nlandu , Hennings Kristian , Farina Dario
Published: May 2007

Normative values of muscle fiber conduction velocity depend on the conditions in which conduction velocity is measured due to the velocity recovery function (VRF) of muscle fibers. In this study the VRF of the compound muscle action potential (CMAP) was assessed following doublet and triplet stimulation in order to investigate the effect of repetitive muscle activation on muscle fiber conduction velocity. The VRF from doublet and triplet activation showed a peak of 4.6%–15.0% and 6.4%–25.9%, respectively, which is not significantly different. The VRF of the CMAP with doublet stimulation had a plateau between 25–75 ms, similar to that reported for single muscle fibers, and changed as a consequence of previous activation. The VRFs with doublet and triplet stimulation were different for interstimulus intervals in the range of 12–250 ms, where the triplet resulted in a plateau of supernormal conduction velocity. The VRF of the triplet could be explained by linear summation of the effects from doublet stimulations only for small distances between the two conditioning stimuli. These results provide new information on the adaptation of membrane properties of muscle fibers to repetitive activation. Changes in CMAP properties due to repeated activation may influence the accuracy of techniques based on CMAP recordings, such as collision methods. Muscle Nerve, 2007
Impact of gravity loading on post‐stroke reaching and its relationship to weakness
Authors: Beer Randall F. , Ellis Michael D. , Holubar Bradley G. , Dewald Julius P.A.
Published: May 2007

The ability to extend the elbow following stroke depends on the magnitude and direction of torques acting at the shoulder. The mechanisms underlying this link remain unclear. The purpose of this study was to evaluate whether the effects of shoulder loading on elbow function were related to weakness or its distribution in the paretic limb. Ten subjects with longstanding hemiparesis performed movements with the arm either passively supported against gravity by an air bearing, or by activation of shoulder muscles. Isometric maximum voluntary torques at the elbow and shoulder were measured using a load cell. The speed and range of elbow extension movements were negatively impacted by actively supporting the paretic limb against gravity. However, the effects of gravity loading were not related to proximal weakness or abnormalities in the elbow flexor–extensor strength balance. The findings support the existence of abnormal descending motor commands that constrain the ability of stroke survivors to generate elbow extension torque in combination with abduction torque at the shoulder. Muscle Nerve, 2007
The impact of component commonality on composite assembly policies
Authors: Eynan Amit , Rosenblatt Meir J.
Published: May 2007

Assemble in Advance (AIA) policy reduces assembly cost due to advance planning, while Assemble to Order (ATO) policy eliminates assembly of excessive (more than demanded) units. The tradeoffs between the two policies have been studied in the past for single product environments. Moreover, it was shown that it is beneficial to employ AIA and ATO simultaneously. In this article, we study the employment of such a composite assembly policy in a multiproduct environment with component commonality. When common components are used, ATO may also enable us to benefit from the risk pooling effect. We provide important managerial insights such as: the multiperiod problem is myopic and changes in inventory levels due to the use of common components, and demonstrate the potential profit increase compared to other policies.© 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007
Science and logistics
Authors: McShane R. E.
Published: May 2007

The report of the panel on “Science and Logistics” of the Fifth Annual Logistics Research Conference is summarized by its chairman.
Contractor performance
Authors: Mackenzie D. C.
Published: May 2007

This revised version of a speech presented at the Bureau of Supplies and Accounts Field Conference of November, 1954, discusses the reasons for delinquent performance under a contract and possible solutions to this problem.
A multi‐stage inventory model
Authors: Bryan J. G. , Wadsworth G. P. , Whitin T. M.
Published: May 2007

An inventory control problem, in which inventory may be maintained on raw materials or on work after each stage of a three‐stage process, is solved.
The problem of aiming and ewasion
Authors: Isaaca Rufus
Published: May 2007

The general problem of a marksman versus a mobile target, with a time lag in the gunner's information as to the target's position, appears in many guises in many situations. It is a classic military problem. Formulated in terms of game theory, the desiderata are: How should the target best maneuver to confound prediction of his positions How and when should the marksman make this prediction? What hit probability is to be expected when both participants behave optimally?

This paper discusses this general class of problems and then settles on one which seems to be the simplest possible example that is not trivial. Nevertheless it is difficult. In two previous papers devoted to it, the evader's best strategy and value of the game were given. Here the emphasis is on the marksman. He has no optimal strategy, but does have an ideal strategy with the property that every near optimal strategy is close to it. He also has a class of passive ε‐strategies such that if and only if he obeys their dictates will he either come within ε of the best hit probability or else always remain in a position where it is possible to do so.
Mathematical treatment of a stockpiling problem
Authors: Danskin J. M.
Published: May 2007

If money is spent too fast while stockpiling for a contingency, production may be highly inefficient. If it is spent too slowly, there may be too little stockpile when the contingency comes. The problem of finding an optimum spending rate in one of these situations is discussed.
A mathematical evaluation of a work sampling technique
Authors: Davis Harold
Published: May 2007

A study of cargo handling methods required a re‐evaluation of a standard work sampling technique. The most interesting conclusion can be qualitatively summarized as follows: if there is evidence that the process lacks any prominent periodic component, then it is better to sample at fixed periods than at random.
A tank duel with game‐theoretic implications
Authors: Zachrisson L. E. , Robbins James J.
Published: May 2007

This article is drawn from a symposium on “Operations Analysis: Basic Ideas; Some Schematized Applications,” which appeared in Artilleri Tidskrift (Stockholm), Vol. 84, No. 3, 1955. It treats a differential game where decisions by each side are made continuously. A weapon's characteristics are pretested by putting it through a hypothetical battle in which a duel occurs between this weapon and a supposed adversary. The model set up here is capable of generalization, and steps ar e used which might be applied to more general battle situations.

For a summary of the entire symposium, see “Military Applications of Operations Research in Sweden,” by James J. Robbins. Operations Research, June 1956, Vol. 4, No. 3.
A method of estimating spare‐part essentiality
Authors: Karr H. W.
Published: May 2007

This paper contains the text of a briefing on a method of estimating spare‐part “essentiality” or “shortage penalties.” The estimates are made by collecting and combining the judgments of individual maintenance specialists. While the talk was primarily directed to a military audience, the subject appears to be of general interest, since the problem of estimating shortage penalties must be faced in applying any of the optimal inventory policies which have been developed in recent years. The quantitative solution of many other management problems also requires input data which can only be obtained on the basis of expert judgment.
Airline demand: An analysis of some frequency distributions
Authors: Beckmann Martin J. , Bobkoski F.
Published: May 2007

Following some trial fittings of Poisson and compounded Poisson distributions, Gamma distributions are fitted to histograms of manifested passengers, to total losses (late cancellations, no‐shows, and misconnections) and to passengers added.
A transportation and production model
Authors: Evans G. W.
Published: May 2007

A transportation and production model is given in which costs of transportation and production are considered. There are no restrictions on the number of transport paths, and losses in transportation as well as those at terminals are incorporated in the model. Also, products of one type may be converted into products of another type at known terminals. There are many applications of interest in the use of this model, where the demands for products are known and the desired solution allocates production in such a manner that the total cost of maintaining the system is minimized.
A bottleneck situation involving interdependent industries
Authors: Bellman Richard , Dreyfus Stuart
Published: May 2007

In this paper, we consider the computational solution of a maximization problem arising in the study of the utilization of interdependent industries. Under the assumption of proportional costs and returns. it is shown that the dimensionality of the problem can always be reduced by one and all the transformations occurring can be taken to be “shrinking transformations.” These transformations greatly improve the efficiency of the method.
A convex programming procedure
Authors: D'esopo D. A.
Published: May 2007

The procedure which involves successively minimizing a convex function with respect to each of its coordinates is shown to converge if constraints are rectangular and the function has continuous derivatives. It is also shown that certain more general procedures, which might be expected to converge more rapidly, are convergent. A criterion is exhibited which yields information concerning the rate of convergence of this method.
For tomorrow's city
Authors: Fisher Joseph L.
Published: May 2007

Urbanization demands initiative and planning to meet essential needs for natural resources.
Phenotypic and functional characterization of mature dendritic cells from pediatric cancer patients
Authors: Jacobs Joannes F.M. , Hoogerbrugge Peter M. , de Rakt Mandy W.M.M. van , Aarntzen Erik H.J.G. , Figdor Carl G. , Adema Gosse J. , de Vries I. Jolanda M.
Published: May 2007

Background

Dendritic cells (DCs) are the most potent antigen‐presenting cells of the immune system. Clinical trials have demonstrated that mature DCs loaded with tumor‐associated antigens can induce tumor‐specific immune responses. Theoretically, pediatric patients are excellent candidates for immunotherapy since their immune system is more potent compared to adults. We studied whether sufficient amounts of mature monocyte‐derived DCs can be cultured from peripheral blood of pediatric cancer patients.

Procedure

DCs from 15 pediatric patients with an untreated primary tumor were cultured from monocytes and matured with clinical grade cytokines. Phenotype and function were tested with flow cytometry, mixed lymphocyte reaction (MLR), and an in vitro migration assay. DCs of children with a solid tumor were compared with monocyte‐derived DCs from age‐related non‐malignant controls.

Results

Ex vivo‐generated monocyte‐derived DCs from pediatric patients can be generated in numbers sufficient for DC vaccination trials. Upon cytokine stimulation the DCs highly upregulate the expression of the maturation markers CD80, CD83, and CD86. The mature DCs are six times more potent in inducing T cell proliferation compared to immature DCs. Furthermore, mature DCs, but not immature DCs, express the chemokine receptor CCR7 and have the capacity to migrate in vitro.

Conclusions

These data indicate that mature DCs can be generated ex vivo to further optimize DC‐vaccination trials in pediatric cancer patients. Pediatr Blood Cancer 2007;49:924–927. © 2007 Wiley‐Liss, Inc.
Growth‐related variations in the Bacillus cereus secretome
Authors: Gilois Nathalie , Ramarao Nalini , Bouillaut Laurent , Perchat Stéphane , Aymerich Stéphane , Nielsen‐LeRoux Christina , Lereclus Didier , Gohar Michel
Published: May 2007

Using 2‐DE, transcriptional gene fusions and cell cytotoxicity assays, we followed changes in the Bacillus cereus strain ATCC14579 secretome, gene expression and culture supernatant cytotoxicity from the end of the vegetative phase up to 5 h after entry into the stationary phase. The concentration of each of the 22 proteins in the culture supernatant was determined at various times. In addition, the stability of the proteins was studied. Fifteen of these proteins, including 14 members of the virulence regulon PlcR, were known or predicted to be secreted. All of the secreted proteins reached a maximum concentration during early stationary phase, but there were significant differences in the kinetics of their concentrations. The time courses of protein concentrations were in agreement with gene expression data, except for cytotoxin CytK, which was unstable, and for the metalloprotease InhA1. Supernatant cytoxicity also peaked in early stationary phase, and the kinetics of cytotoxicity paralleled the time course of concentration of the PlcR‐controlled toxin, CytK. Our concomitant study of the time course of protein concentrations, gene expression and supernatant cytotoxicity reveals that the pathogenic potential of B. cereus peaks during the transition state. It also suggests that there is diversity in the regulation of gene expression within the PlcR regulon.
Superconducting phases in strontium ruthenate
Authors: Wysokiński Karol I. , Litak G. , Annett J. F. , Györffy B. L.
Published: May 2007

We review our recent work concerning the search for the superconducting state realised in Sr2RuO4. The orbital symmetry of the order parameter in this spin triplet superconductor is widely believed to be chiral one with d ‐vector along the crystal c‐axis. The three band, three dimensional model with two different phenomenological interaction parameters is able to explain most of the existing data in quantitative way. This is also true for the recently observed “rotation” of the d ‐vector in magnetic field directed along c‐axis. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Decoherence in flux qubits on mesoscopic nonsuperconducting rings
Authors: Kurpas M. , Dajka J. , Zipper E.
Published: May 2007

The problem of decoherence in recently proposed flux qubits built on mesoscopic normal metal rings is studied. The relaxation and dephasing times coming from the interaction of the qubit with the measuring device are calculated within the weak coupling spin‐boson model. We analyze the effect of the measuring apparatus on the relaxation and dephasing times. The possibility of ohmic approximation for the bath is investigated. Considerably long decoherence times are found. The work is limited to the weak damping regime in low temperatures. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Particle–hole asymmetry in the scanning tunneling spectroscopy of the high temperature superconductors
Authors: Gorczyca Anna , Krawiec Mariusz , Maśka Maciej M. , Mierzejewski Marcin
Published: May 2007

There is still no consensus on the mechanism that is responsible for a particle–hole asymmetry observed in scanning tunneling spectroscopy of high‐temperature superconductors. According to the most popular hypothesis this asymmetry results from strong Coulomb correlations in a nearly half‐filled band. In the present paper we propose another mechanism that leads to such asymmetry. It originates from the coupling between the superconductor and the substrate that the system is deposed on. We show that this coupling gives rise to the particle–hole asymmetry only in the case of an anisotropic superconductivity. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fabrication and characterization of nano‐porous GaN template for strain relaxed GaN growth
Authors: Hartono H. , Soh C. B. , Chua S. J. , Fitzgerald E. A.
Published: May 2007

A simple and cost‐effective Si‐doped porous GaN is fabricated by UV‐enhanced electrochemical etching, produces a high density of uniform pores across the surface. TEM reveals that the etching results in layered nano‐pores structures along the (0001) direction. A red shift of 0.7 cm–1 in the E2 (high) phonon peak of GaN from micro‐Raman corresponds to a relaxation of compressive stress in the porous GaN surface with respect to the underlying epitaxial GaN. Subsequent growth of GaN layer on the porous template results in air gap formation, which is believed to serve as sinks for dislocations for reducing residual strain in the film. Reduction of FWHM of the XRD rocking curve by as much as 0.033° and doubling of the intensity of the PL spectrum clearly show improvement on the crystalline and optical quality of the overgrown GaN layer as compared to the as‐grown. A red shift of ∼0.4 cm–1 towards the stress‐free GaN also indicates a relaxation of compressive stress in the overgrown GaN layer. Such a template is useful for high quality GaN growth. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical polarization anisotropies in GaN films for different nonpolar orientations
Authors: Grahn Holger T.
Published: May 2007

We have used polarized photoreflectance spectroscopy to study the electronic‐band‐structure modification of GaN films grown along different nonpolar orientations due to biaxial, anisotropic in‐plane strain. For nonpolar oriented films, the c‐axis of GaN lies in the film plane. In four different GaN films with a nonpolar orientation (M ‐ and A ‐plane), we observe a large in‐plane optical polarization anisotropy, which is much larger for the M ‐plane films due to the much larger strain in at least one of the in‐plane directions. The experimental results for the transition energies and oscillator strengths are compared with theoretical results obtained using the k·p perturbation approach. The large optical polarization anisotropy in M ‐plane GaN films can be used for polarization filtering and polarization‐sensitive photodetectors. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Selective growth of GaN nanocolumns by Al thin layer on substrate
Authors: Ishizawa Shunsuke , Sekiguchi Hiroto , Kikuchi Akihiko , Kishino Katsumi
Published: May 2007

For the application of GaN nanocolumns, one of the most important issues is to control their shapes and positions. We demonstrated a selective RF‐MBE growth of GaN nanocolumns using patterned Al thin pre‐deposited layers on a substrate via their nitridation. As the nanocolumns were grown at the edge of the nitrided Al patterns, a possibility of controlling the shape and the position of nanocolumns was suggested. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Measurement and analysis of international air parcel shipping environment for DHL and FedEx between Europe and United States
Authors: Garcia‐Romeu‐Martinez Manuel‐Alfredo , Singh S. Paul , Cloquell‐Ballester Vicente‐Agustin , Saha Koushik
Published: May 2007

Various studies have been conducted to determine the dynamics that single packages undergo during distribution between destinations as a function of package size and weight and carrier. Previous studies have normally focused on regional and domestic measurements of these environments in Europe and North America. However, no information is available to determine the international handling and shipping environment of single parcels between the two continents. This study used instrumented packages containing triaxial accelerometers. The measured shocks were analysed to determine the velocity change levels as a function of the events measured in the distribution environment and to develop data for drop heights that can be used for package testing. This study provides a comparison of DHL and FedEx, the two largest international parcel carriers. Copyright © 2007 John Wiley & Sons, Ltd.
First principles electronic structure and band gap pressure coefficient for cadmium‐oxide
Authors: Boettger Jonathan C.
Published: May 2007

The static–lattice equation of state (EOS) and electronic energy bands of rocksalt structure cadmium‐oxide (CdO) have been calculated for lattice constants ranging from 9.2 to 8.2 bohr, with and without relativistic corrections included, using two distinct density functional theory models; the local density approximation (LDA) and the generalized gradient approximation (GGA). The zero‐pressure lattice constants obtained with the LDA and GGA models bracket the measured value. For all models considered here, the fundamental band gap decreases linearly with increasing lattice constant over the full range of the calculations. The calculations with relativistic corrections incorrectly predict that CdO is a metal at ambient conditions, transforming to an insulator under pressure. The nonrelativistic calculations predict insulating behavior for all pressures greater than or equal to zero. The large discrepancies between previous predictions of the energy gap for CdO are shown to be due to model differences, not methodological variations. The predicted pressure coefficient for the fundamental band gap is positive and ranges from 13 to 22 meV/GPa, depending on the model used, with the “best” estimate being 15 meV/GPa. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Scattering by a triangular barrier
Authors: Lefebvre Roland
Published: May 2007

We consider a barrier of triangular shape separating a field‐free region from a region where a constant electric field is acting on a particle. This is a completely soluble model. Analytic expressions are provided for the transmission and reflection amplitudes, for a particle coming either from the field‐free region or from the field‐on region. We stress the importance of using the same normalization of the wave functions in the two regions. The resonances supported by this potential are studied. Finally it is shown that it is possible to go in a continuous way from the triangular barrier to the step potential. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Impact of internal electron transfer on the structure of C74 encapsulating Sc and La metal atom impurities
Authors: Liu Dan , Hagelberg Frank
Published: May 2007

Frontier orbital theory as well as the Hückel 4n + 2 rule are discussed as guiding principles for the design and the interpretation of metallofullerene architecture where systems of the form Mi@C74 (M = Sc, La; i = 1,2) serve as examples. Transfer of electrons from the metal impurities to the fullerene enclosure populates preferentially the low‐lying unoccupied molecular orbitals of the cage. It further tends to induce aromaticity in the C5 rings neighboring the impurity sites. These observations are used to derive systematically stable structures of the studied mono‐ and dimetallofullerenes. Various geometries and spin states of M2@C74 (M = Sc, La) are considered, and novel ground state candidates are proposed. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
SitCon: Binding site residue conservation visualization and protein sequence‐to‐function tool
Authors: Kairys Visvaldas , Fernandes Miguel X.
Published: May 2007

We introduce SitCon (SITe CONservation), a program designed to explore conservation of functionally important sites in a series of hypothetically homologous candidate protein structures, given amino acid sequence as an input. This can especially be useful when looking for an unknown function of a protein. SitCon exploits the fact that binding sites of proteins are preserved better than the overall residue sequence conservation. To test the capability of unknown function prediction, we randomly chose known function proteins from Caenorhabditis elegans genome. To imitate a behavior of an unknown function target, only the low homology proteins with 0.01 < E‐score ≤ 100 were analyzed as templates. Out of 29 enzyme targets, SitCon was able to provide various hints about their function in at least 69% of the cases. For the eight nonenzyme targets, the predictions matched in only 25% of the cases. SitCon was also tested for a capability to predict presence or absence of metal‐containing heterogroups in the target enzymes with ∼80% success rate. Because this algorithm is not based on specific protein signatures, it may allow detection of overlooked relationships between proteins. SitCon is also very effective as a tool allowing visual comparison of binding site residue conservation between the target and homologous templates side‐by‐side. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Application of the ONIOM (QM/QM) method in the study of molybdena–silica system active in olefin metathesis
Authors: Handzlik Jarosław
Published: May 2007

The two‐layer ONIOM method is applied for description of Mo‐methylidene center on silica, which is the active site of olefin metathesis. Two clusters of different size are employed to model the silica surface. For the larger one, two differently defined inner layers (the model systems) are tested. In all the calculations, the B3LYP functional is adopted for the inner layer, while the Hartree–Fock method or the local density approximation (SVWN5 functional) is used for the treatment of the real system. Based on the reference results obtained for the real system from the B3LYP calculations, it is concluded that both B3LYP:HF and B3LYP:SVWN5 schemes are suitable for proper description of the geometry of the Mo center and its activity in ethene metathesis. The former combination is a little better choice, however. It is also shown that the inner layer, including the third coordination sphere of molybdenum, is large enough to obtain satisfactory results. On the other hand, the relative energies and some geometrical parameters of the active site are dependent on the size of the entire system studied. The sensitivity of the geometrical parameters and reaction energies to the changes of the scale factor g, involved in the ONIOM scheme, is studied as well. It is concluded that the link atom distance is not crucial for obtaining correct results. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
A noteworthy feature of bond dissociation/formation reactions
Authors: Politzer Peter , Murray Jane S. , Lane Pat , Toro‐Labbé Alejandro
Published: May 2007

The reaction force F(Rc) of a process is the negative derivative of the potential energy V(Rc) of the system with respect to the intrinsic reaction coordinate Rc. For the dissociation of a bond, F(Rc) has a negative minimum at a point Rc = α, while for the formation of the same bond, F(Rc) has a maximum at Rc = α. These extrema divide the respective processes into two phases. For the dissociation, these correspond to an initial stretching of the XY bond (structural effect) followed by separation into the fragments X and Y (electronic effects); for bond formation, the electronic phase is first (attractive interaction and gradual bond formation) and then the structural (relaxation to equilibrium separation). The noteworthy feature is that the key point Rc = α always is such that V(α), relative to the minimum of V(Rc), is about 27% of the dissociation energy. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
pKa optimized catalysis in serine proteinases, an ab initio study on the catalaytic His
Authors: Hudáky Péter , Perczel András
Published: May 2007

First principle models of catalytic apparatus of enzymes can be used for studying stability as well as the atomic details of a catalytic mechanism. For example, the catalytic triad of chymotrypsin was recently investigated by using an ab initio geometry optimized (Hudáky and Perczel, Proteins: Struct Funct Genet, 2006, 62, 749) self‐stabilizing molecule ensemble without the presence of the complete enzyme and substrate. Several parameters of the above catalytic reaction turned out to be the same within the model and the in vitro enzymatic reaction. Among the numerous parameters of the catalytic process geometrical changes of the catalytic histidine was investigated here and the variation of its pKa value was determined. A relatively large range, 3.5 unit, was determined as the variation of pKa as function of the conformational subspace available in serine proteases. Comparing PDB structures of the free and the complex enzymes it was shown, that histidine, after accepting the proton from the OH group of the catalytic serine, undergoes a minor conformational change accompanied by a 2.5 unit decrease in pKa. We conclude that the changes of pKa during catalysis are predominantly determined by the geometrical arrangement of the histidine moiety and this change serves as a significant driving force in the catalytic process. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007