bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of ice hockey facial protectors on the response time and kinematics in goal-directed tasks
Authors: Dowler P M , Pearsall D J , Stapley P J
Published: July 2009

Ice hockey facial protectors are essential to prevent eye (and, in some cases, dental) injuries but must also not encumber vision and, in turn, playersapos; performance. The purpose of this study was to investigate the effects of three different facial protection conditions on temporal and kinematic parameters in a goal-directed pointing task: helmet (control), visor, and cage. Start and end target switches captured temporal estimates (reaction time (RT), movement time, (MT), and response time (RT+MT)), while a 13-light target array and 6-camera Vicon Mx system were used to collect upper-body kinematics data (head and thorax orientation, shoulder and elbow joint angles). Subjects recruited were 16 male and 12 female varsity ice hockey players ( n=28). Results demonstrated that, although kinematics remained largely unaffected, throughout the target array RTMT increased significantly with the cage (23 ms) as well as delayed initiation of head rotation for both the visor (14 ms) and the cage (18 ms). These differences may well represent a functional disadvantage to a player's performance given the dynamic open environment where multiple players contest for puck possession. It must be stressed that facial protectors still provide an effective form of protection and thus should still be worn at all levels of play. In summary, further research is warranted to achieve both optimal performance and safety.
Looking at Molecular Orbitals in Three-Dimensional Form: From Dream to Reality
Authors: Takahashi Masahiko
Published: July 2009

Over the last four decades an experimental method has been developed for looking at electron orbitals in momentum space. The method, called electron momentum spectroscopy (EMS), is based on the electron-impact ionizing reaction near the Bethe ridge at incident electron energies of the order of 1 keV or higher. This account reviews frontiers of the field, involving the first approach to molecular frame EMS that enables one to look at molecular orbitals in three-dimensional form.
A Convenient Access to (All-rac)-α-Tocopherol Acetate from Linalool and Dihydromyrcene
Authors: Gembus Vincent , Sala-Jung Nathalie , Uguen Daniel
Published: July 2009

Refluxing trimethylhydroquinone 2 in 10:1 dodecane/CH2Cl2 with linalool 3b (two-fold excess) and camphorsulfonic acid, then treating the crude condensation product (consisting of a mixture of the chromanols 1b and 1c, alongside the tricyclic compounds 9 and 10) sequentially with Ac2O and m-CPBA afforded, after removal by column chromatography of the 9/10 acetates, a mixture of the regioisomeric epoxides 1jOAc and 1kOAc (ratio 9:1, total 60%). Treatment of this mixture with Al(O-i-Pr)3 followed by CuI-catalysed Wurtz coupling of the acetates of the resulting allylic alcohols with citronellylmagnesium chloride 12a, and finally hydrogenation then provided the title acetate (overall 46% from 2).
Efficient Access to (All-rac)-α-Tocopherol Acetate by a Crombie Chromene Synthesis
Authors: Gembus Vincent , Sala-Jung Nathalie , Uguen Daniel
Published: July 2009

In contrast to reports in the literature, the pyridine-catalysed condensation of phenolic compounds and conjugated aldehydes to chromenes was found to be applicable to trimethylhydroquinone 2a with the result of complementary convergent approaches to the title acetate using citral 3a and dihydromyrcene 9 as precursors of the phytyl residue.
Optical Properties and Chemical Compositions of Iodine-Containing Aerosols Produced from the Atmospheric Photolysis of Methylene Iodide in the Presence of Ozone
Authors: Sakamoto Yosuke , Yabushita Akihiro , Kawasaki Masahiro , Nakayama Tomoki , Matsumi Yutaka
Published: July 2009

Optical properties of iodine-containing aerosols that were produced by ultraviolet photoirradiation of a mixture gas of CH2I2 and O3 with dry air diluent have been measured using a nephelometer, a particle soot absorption photometer and a cavity ring-down spectrometer. Single scattering albedo of iodine aerosols was determined to be 0.96 ± 0.01 at around 530 nm. Chemical compositions of the aerosols associated with particle size in the range of 0.2–1 µm was measured using a laser-ionization single-particle aerosol mass spectrometer. Positive and negative ion signals of iodine and iodine oxides, IOn (n = 0–4), I2On (n = 0–6), and I3On (n = 0–1), carbon-containing compounds and HOI were detected.
Remarkably Stabilized Charge Separations in Inorganic Nanospace
Authors: Yui Tatsuto , Tsuchino Takako , Mino Hiroyuki , Kajino Tsutomu , Itoh Shigeru , Fukushima Yoshiaki , Takagi Katsuhiko
Published: July 2009

A remarkably stable and continuous photoinduced charge separation with a half lifetime longer than 2.5 h in ambient atmosphere was observed at the interface of mesoporous silica and titania nanosheets involving porphyrins and viologen in their nanospaces, respectively.
Decision‐making about the use of hormone therapy among perimenopausal women
Authors: Huston Sally A. , Bagozzi Richard P. , Kirking Duane M.
Published: July 2009

Objectives. Women reaching menopause must make a controversial decision about whether to use hormone therapy (HT). The theory of planned behaviour (TPB) was the organizing framework. The objectives were to determine if (1) influence of different TPB constructs varied with stage of menopause and HT use, (2) women with diabetes were influenced in significantly different ways from women without, (3) the overall perceived behavioural control (PBC) and self‐efficacy (SE) have independent effects on intention, and (4) physician influence was mediated by subjective norm (SN).

Design. Cross‐sectional survey of women from a managed care organization.

Methods. Multiple regression analysis was used to analyse 765 responses (230 from women with diabetes) and separately four main subgroups: (1) early menopause stage and never used HT, (2) late menopause stage and never used HT, (3) late menopause stage and previously used HT, and (4) late menopause stage currently using HT.

Results. For the entire sample, the model explains 68% of variance in intention, where SE, physicians' influence, self‐identification with menopause as a natural part of ageing, self‐identification as someone who wants to delay menopause, HT status, menopause status, and diabetes were added to the TPB. For the entire sample, SE added 2% to the explained variance and the physician determinant added 7%.

Conclusions. An augmented TPB is useful for understanding women's HT use decisions. The theory explains more variance in intention before a behaviour is enacted than after, and decision structure changes over time. PBC and SE have independent effects on intention.
Simulated Maximum Likelihood Estimator for the Random Coefficient Logit Model Using Aggregate Data
Authors: Park Sungho , Gupta Sachin
Published: July 2009

The authors propose a simulated maximum likelihood estimation method for the random coefficient logit model using aggregate data, accounting for heterogeneity and endogeneity. The method allows for two sources of randomness in observed market shares: unobserved product characteristics and sampling error. Because of the latter, the method is suitable when sample sizes underlying the shares are finite. In contrast, Berry, Levinsohn and Pakes's commonly used approach assumes that observed shares have no sampling error. The method can be viewed as a generalization of Villas-Boas and Winer's approach and is closely related to Petrin and Train's “control function” approach. The authors show that the proposed method provides unbiased and efficient estimates of demand parameters. They also obtain endogeneity test statistics as a by-product, including the direction of endogeneity bias. The model can be extended to incorporate Markov regime-switching dynamics in parameters and is open to other extensions based on maximum likelihood. The benefits of the proposed approach are achieved by assuming normality of the unobserved demand attributes, an assumption that imposes constraints on the types of pricing behaviors that are accommodated. However, the authors find in simulations that demand estimates are fairly robust to violations of these assumptions.
Die tumben und die wîsen. Wolframs ›Parzival‹-Prolog neu gedeutet
Authors: Powell Morgan
Published: July 2009

Recent scholarly consensus has seen the prologue to ›Parzival‹ as an attempt to introduce the audience to the difficulties of a previously unarticulated poetics of fiction and truth. This new reading likewise sees the prologue as a communication with the audience about the limits and possibilities of narrative, but situates Wolfram's images firmly within the context of contemporary epistemological debate and poetic positioning. The result is not a poetics of fiction, but an ontological reversal of the visible and experiential in relationship to truth, not hakenschlagender obscurantism, but a clearly delineated opposition between a layman's and a cleric's way of knowing.
An Analysis of the WTO Panel Ruling on GMOs Disputes: Focusing on the Interpretation and Application of Articles 2.2, 5.1 and 5.7 of the SPS Agreement
Authors: Chen Hui-Chih , Ni Kuei-Jung
Published: July 2009

The transboundary movement of Genetic Modified Organisms (GMOs) has become a focal point of the international community. The control of GMOs involves huge economic interests and the protection of the environment and public health. In 2003, the World Trade Organization (WTO) at the request of GMOs-producing countries established a Panel in adjudicating the consistency of European nations' restriction on trade of GMO products under WTO rules. Given the high controversy and sensitivity of the dispute, the Panel had conducted a very lengthy deliberation and finally reached a conclusion in September of 2006. This article aims to analyze the legal reasoning of the decision, focusing on how the tribunal interpreted and applied certain critical provisions governing the issue. It is found that this ruling took a rigid stand on the justification of applying trade restrictions on GMOs, although the right of WTO members to protect national health has been fairly reaffirmed.
Risk assessment for preeclampsia in women with gestational diabetes mellitus
Authors: Phaloprakarn Chadakarn , Tangjitgamol Siriwan
Published: July 2009

Aim: To develop a clinical model to assess the risk of preeclampsia in women with gestational diabetes mellitus (GDM).

Methods: We studied clinical characteristics of 813 consecutive women who had GDM between January 2003 and February 2008 at our institution. The clinical features which were significantly associated with preeclampsia by multiple logistic regression analysis were integrated into a risk model. The diagnostic performance of this model was then evaluated from a receiver-operating characteristic (ROC) curve analysis.

Results: A total of 78 women with GDM (9.6%) developed preeclampsia. In a multivariable analysis, first-trimester BMI ≥27 kg/m2 (P<0.001), GDM diagnosed within 20 weeks of gestation (P<0.001), and poor glycemic control (P<0.001) were associated with preeclampsia. These three factors were incorporated into a risk-scoring model which ranged from 0 to 3 points. At the optimal cut-off score of ≥2, the sensitivity, specificity, and area under the curve (AUC) for preeclampsia were high at 76.9% [95% confidence interval (CI) 69.0–85.2], 92.8% (95% CI 85.9–98.1), and 0.849 (95% CI 0.792–0.905), respectively.

Conclusion: A model based on clinical data yielded predicted the development of preeclampsia in women with GDM.
The infant incubator in the neonatal intensive care unit: unresolved issues and future developments
Authors: Antonucci Roberto , Porcella Annalisa , Fanos Vassilios
Published: July 2009

Since the 19thcentury, devices termed incubators were developed to maintain thermal stability in low birth weight (LBW) and sick newborns, thus improving their chances of survival. Remarkable progress has been made in the production of infant incubators, which are currently highly technological devices. However, they still need to be improved in many aspects. Regarding the temperature and humidity control, future incubators should minimize heat loss from the neonate and eddies around him/her. An unresolved issue is exposure to high noise levels in the Neonatal Intensive Care Unit (NICU). Strategies aimed at modifying the behavior of NICU personnel, along with structural improvements in incubator design, are required to reduce noise exposure. Light environment should be taken into consideration in designing new models of incubators. In fact, ambient NICU illumination may cause visual pathway sequelae or possibly retinopathy of prematurity (ROP), while premature exposure to continuous lighting may adversely affect the rest-activity patterns of the newborn. Accordingly, both the use of incubator covers and circadian lighting in the NICU might attenuate these effects. The impact of electromagnetic fields (EMFs) on infant health is still unclear. However, future incubators should be designed to minimize the EMF exposure of the newborn.
Reduction of IGF-binding protein-3 as a potential marker of intra-uterine growth restriction
Authors: Baker Méio Maria Dalva Barbosa , Lopes Moreira Maria Elizabeth , Sichieri Rosely , Moura Aníbal Sanchez
Published: July 2009

Background: Growth factor-binding proteins influence the growth of infants starting in utero. Adaptation of the fetus to an adverse uterine environment is associated with changes in the growth hormone-growth factor-insulin axis.

Aims: To evaluate serum levels of IGF-I and IGFBP-3 in small and appropriate for gestational age newborn infants.

Methods: Fifty-four newborn infants, small (SGA, n=28) or appropriate (AGA, n=26) for gestational age were matched by gestational age and sex. Blood was collected on the first day of life, and anthropometric measurements were taken at birth. The serum levels of IGF-I and IGFBP-3 were compared, and correlated with the anthropometric measurements.

Results: On the first day of life, mean serum IGFBP-3 levels were significantly lower in SGA babies and correlated with weight, length, head circumference, and ponderal index (weight/length 3) (P<0.0001). In contrast, no associations were found between IGF-I serum levels and these anthropometric measurements.

Conclusion: Our data show that SGA babies have significantly reduced IGFBP-3 concentrations at birth.
The metabolic syndrome and the risks of unfavourable outcome of pregnancy
Authors: Horváth Boldizsár , Kovács Lajos , Riba Mária , Farkas György , Bödecs Tamás , Bódis József
Published: July 2009

A metabolikus szindróma jellemzői a hasi elhízás, a magas vérnyomás, az éhhomi glükóz és dyslipidaemia együttes előfordulása. A vizsgálat célja, hogy feltárja a metabolikus anyagcserezavar és egyes terhességi szövődmények kapcsolatát.
Anyag és módszer:
A releváns kódok alapján retrospektíve leválogatott digitális adatbázisból a 2005–2008 közötti vizsgált időszakban (4 év) a kórházi dokumentációkban 5869 várandós anya gondozási adataival rendelkeztek. Százhetvenkettő anya (2,9%) esetében a várandósságuk első harmadában a metabolikus tünetegyüttes jellemzői szerepeltek. Ezen betegek adatait részletesen megvizsgálták, feldolgozták és releváns adataikat a többi várandós hasonló dokumentációival összehasonlították.
Eredmények:
A metabolikus tünetegyüttes tüneteit mutató csoportban a koraszülési arány 15,1% (26/172) volt, míg a metabolikus szindrómától mentes esetekben az idő előtti születés csupán 11,7% volt [OR: 1,52 (95%-os CI: 0,996–2,33) p=0,051]. Az anyagcserezavarban érintettek csoportjában 32 anyánál intrauterin növekedési zavart észleltek, míg ezen tünetegyüttes nélküli esetekben ez csupán 3,6%-ban (205/5697) fordult elő [OR: 6,38 (95%-os CI: 4,24–9,61) p<0,001)]. A vizsgált csoportban 47 praeeclampsiával szövődött várandósságot észleltek (27,3%), szemben a beteganyaguk további részével, ahol a terhességi mérgezés előfordulása 4,7% volt [OR: 7,93 (95%-os CI: 5,54–11,33) p<0,001]. A metabolikus tünetegyüttesben szenvedők körében 67 (38,2%) olyan beteg volt, aki több mint egy, a betegségre jellemző szülészeti szövődményben szenvedett. A kontrollcsoportban ugyanez az arány 17,0%-nak adódott [OR: 3,11 (2,27–4,26) p<0,001]. A metabolikus szindróma által érintett csoportban csupán 47 (27,3%) olyan esetet találtak, akik várandósságuk és szülésük alatt tünetmentesek voltak, míg az 5697 anyából, akiknél az első terhességi harmadban a metabolikus tünetegyüttes jeleit nem észlelték, szignifikánsan kedvezőbb arányban (74,1%, 4220 várandós) voltak olyan anyák, akik minden szövődmény nélkül viselték várandósságukat [OR: 0,132 (0,09–0,18) p<0,001].
Következtetések:
A metabolikus szindróma irodalmi adatok alapján és saját megfigyeléseik szerint is jelentős szerepet játszik a szövődményes várandósságok kialakulásában, elsősorban a gyulladásos faktorok és a fokozott trombóziskészség provokálásával. Számos irodalmi adat utal arra, hogy a metabolikus tünetegyüttes esetén a már a koncepció idején alkalmazott heparinkezelés eredményes lehet. 2007-ben prospektív vizsgálatot indítottak azzal a céllal, hogy megismerjék, vajon az alacsony molekulatömegű heparin megelőző célú kezelés, segít-e elkerülni ennek az anyagcserezavarnak a kedvezőtlen következményeit? Reményeik szerint a 2010-es évektől a heparinkezelés eredményeiről adatokkal rendelkeznek.
Restenosis following endovascular interventions: clinical and experimental studies
Authors: Hirschberg Kristóf , Entz László , Szabó Gábor , Merkely Béla
Published: July 2009

A vascularis intervenciókat követő restenosis fontos limitációja ezen beavatkozások hosszú távú sikerének. A restenosis gyakorisága az atheroscleroticus szűkület kezelési módjától (stentelés, endarterectomia) és érterülettől függően igen változó, de a rizikófaktorok és patomechanizmus tekintetében sok a hasonlóság. Jelen közlemény a szerzők ez irányban végzett tanulmányainak összefoglalója. Klinikai munkákban a carotisendarterectomia és carotisstentelés utáni restenosisarányok összehasonlítását végezték el, valamint a két beavatkozás utáni komplementaktiváció jellemzőit elemezték. Az ösztrogénreceptor-alfa polimorfizmusainak szerepét vizsgálták a carotisintervenciók után fellépő restenosisban. A carotisendarterectomia állatmodelljén a nitrogén-monoxid-ciklikus guanozin-monofoszfát-jelátvitel szerepét vizsgálták a neointimalis hyperplasia alakulására foszfodiészteráz-5-gátló terápia mellett. Eredményeik szerint a carotisendarterectomia után megfigyelhető nagyobb restenosisarány ezen beavatkozás után kifejezettebb komplementaktivációval lehet összefüggésben. A restenosishoz vezető neointimalis hyperplasia kialakulásában az ösztrogénreceptor mutációi is szerepet játszhatnak, elsősorban nőkben carotisendarterectomia után. A ciklikus guanozin-monofoszfát-jelátvitel serkentésével a neointimalis hyperplasia gátolható.
Botulinum toxin therapy for focal dystonia
Authors: Hahn Katalin , Niklai Erzsébet , Garzuly Ferenc , Szupera Zoltán
Published: July 2009

A dystoniák fő jellemzője a tartós izomgörcsök kialakulása. Ezek csavaró és folyamatosan ismétlődő mozgásokat okoznak, vagy kóros tartás kialakulásához vezetnek. Kezelésük gyógyszerrel, műtéti úton, botulinum toxin injekcióval és egyéb, kiegészítő eljárásokkal történhet. A szerzők 1991 óta alkalmazzák a botulinum toxin kezelést.
Célkitűzés:
A szerzők azt vizsgálták, mennyire hatékony és biztonságos a botulinum toxin alkalmazása fokális dystoniák és hemifacialis spasmus esetén.
Módszer:
Kilencvennégy beteget vizsgáltak, átlagéletkor 62,4 év, a kezelés átlagos ideje 6,8 év. A betegek megoszlása a dystonia típusa szerint a következő: torticollis spastica 33 fő, blepharospasmus 32 fő, hemifacialis spasmus 29 fő. A kezelés A típusú botulinum toxin injekcióval történt. A kezelés hatását a Patient Global Impression skálával mérték. Emellett elemezték a mellékhatásokat, a szövődményeket és a kezelés megszakításának az okait.
Eredmények:
A botulinum toxin kezelés 92%-ban volt hatásos. Ezen belül klinikailag jelentős javulást a betegek 56%-a ért el. A hatásosság tekintetében nem volt statisztikai különbség sem a dystoniák típusai (torticollis spastica 87%, blepharospasmus 93% és hemifacialis spasmus 96%), sem az alkalmazott készítmények között (Botox 92%, Dysport 92%). Hat betegnél fordult elő átmeneti gyengeség. Jelentős mellékhatást vagy szövődményt nem észleltünk.
Következtetések:
A vizsgálat eredményei azt igazolják, hogy a botulinum toxin injekció hatékony és biztonságos kezelés torticollis spastica, blepharospasmus és hemifacialis spasmus esetén.
Whipple’s disease. Do we think of it enough?
Authors: Fischer Tünde , Tiboly Márta , Tóth Péter , Szenes Mária , Völgyi Zoltán , Bali Otília , Gasztonyi Beáta
Published: July 2009

A Whipple-kór egy krónikus, szisztémás, relapsusokkal kísért, kezelés nélkül halálos kimenetelű bakteriális megbetegedés, amely jelentős diagnosztikus kihívást jelent mind a klinikusok, mind a patológusok számára. A betegség az esetek 80%-ában a középkorú, fehér, kaukázusi férfiakat érinti.Célkitűzés:A szerzők három eset kapcsán mutatnak rá a kórkép diagnosztikájának nehézségeire, valamint irodalmi áttekintést adnak a betegség etiológiájáról, klinikumáról, feltételezett patomechanizmusáról, valamint a kezelés lehetőségeiről.Következtetés:A kórkép kialakulásában immunológiai tényezők játszanak szerepet, azonban még nem tisztázott azok primer vagy szekunder jellege. Elsősorban a bélrendszer betegsége, azonban az extraintestinalis tünetek gyakran évekkel, évtizedekkel megelőzik az intestinalis tünetek megjelenését és a diagnózis felállítását. A betegség igazolásának klasszikus eszköze a vékonybél-biopsziás minták perjódsav-Schiff festése, valamint a kórokozó polimeráz láncreakcióval történő igazolása. A megfelelő antibiotikum kiválasztása és a terápia időtartama empirikus, azonban a kezelésre a legtöbb esetben azonnali válasz következik be. A relapsusok különösen központi idegrendszeri érintettség esetén gyakoriak.
Frequencies of the Los Angeles and Duarte galactose-1-phosphate uridyltransferase variant alleles in the Hungarian population
Authors: Milánkovics Ilona , Schuler Ágnes , Németh Krisztina , Somogyi Csilla , Fekete György
Published: July 2009

A klasszikus galactosaemia autoszomális recesszív módon öröklődő anyagcsere-betegség, amelynek hátterében a galaktóz-1-foszfát-uridil-transzferáz (GALT) enzim defektusa áll. Hazánkban a betegséget az újszülöttkori tömegszűrés keretében, 1976 óta szűrik. A p.N314D mutáció asszociál a GALT enzim Los Angeles és a Duarte variánsaival, attól függően, hogy a mutáció mely polimorfizmusokkal öröklődik együtt
cis
helyzetben.
Célkitűzés:
Munkánk célja volt a magyar egészséges populációban a p.N314D mutáció, valamint a Los Angeles és Duarte variánsok gyakoriságát meghatározni.
Módszerek:
A 100 donor személyből izolált genomiális DNS-mintát polimeráz láncreakció során amplifikáltuk, majd restrikciós endonukleázzal emésztettük.
Eredmények:
A p.N314D mutáció, a Los Angeles variáns és a Duarte variáns allélgyakorisága az általunk vizsgált populációban 11,5%, 2,5%, illetve 9% volt.
Következtetés:
A magyar populációban a Los Angeles és Duarte varánsok allélgyakorisága jól korrelál más kaukázusi populációkban detektált gyakoriságokkal.
Possible role of selected IGR and SLC22A4/SLC22A5 loci in development of inflammatory bowel diseases
Authors: Lakner Lilla , Csöngei Veronika , Magyari Lili , Varga Márta , Miheller Pál , Sarlós Patrícia , Orosz Péter , Bári Zsolt , Takács István , Járomi Luca , Sáfrány Enikő , Sipeky Csilla , Bene Judit , Tulassay Zsolt , Döbrönte Zoltán , Melegh Béla
Published: July 2009

Az idiopathiás krónikus gyulladásos bélbetegség kialakulásában környezeti tényezők, immunológiai és genetikai faktorok egyaránt szerepet játszanak. Az utóbbi években a CARD15 gén mellett egyre több adat támasztja alá más gének, többek között az 5q31-33 régióban elhelyezkedő IBD5 locus (MIM#606348) szerepét. Egyes tanulmányok ezen régióban az SLC22A4 gén C1672T szubsztitúciójának, illetve az SLC22A5 gén G-207C transzverziójának együttes szerepét hangsúlyozzák, különösen Crohn-betegség kialakulásában, míg más szerzők új minor hajlamosító tényezőket azonosítottak az IBD5 kromoszómarégióban, ezek az IGR-variánsok.
Célkitűzés:
Az SLC22A4 C1672T és SLC22A5 G-207C mutációk mellett az IGR2096a_1 (rs12521868) és az IGR2198a_1 (rs11739135) polimorfizmusok szerepének vizsgálata gyulladásos bélbetegség kialakulásában.
Betegek és módszer:
Vizsgálatunk során 440 gyulladásos bélbeteg (206 Crohn- és 234 colitis ulcerosás beteg), valamint 279 kontrollegyén perifériás vérmintájából PCR-RFLP technikával végeztünk DNS-analízist.
Eredmények:
Sem a C1672T, sem a G-207C allélek, sem a TC haplotípus nem bizonyult rizikófaktornak sem Crohn-betegség, sem colitis ulcerosa esetében. Ezzel ellentétben mindkét minor IGR allél frekvenciája: mind az IGR2096a_1 T (48,1%), mind az IGR2198a_1 C (46,1%) szignifikánsan magasabb volt Crohn-betegségben a kontrollokéhoz (38,5%, 38,4%) képest (p<0,05). Korra és nemre standardizált regressziós analízissel mindkét allélnél fokozott rizikót észleltünk Crohn-betegség vonatkozásában (T-allél: OR=1,694, 95%-os CI: 1,137–2,522, p=0,010, C-allél: OR=1,644, 95%-os CI=1,103–2,449, p=0,015). Colitis ulcerosa esetén nem találtunk összefüggést a két IGR-variáns és a betegség kialakulása között.
Következtetés:
az IGR minor alléleknek a környező kaukázusi népcsoportoktól eltérően magyarországi populációban szerepük lehet a Crohn-betegség kialakulásában.
Pad Topography, Contact Area and Hydrodynamic Lubrication in Chemical-Mechanical Polishing
Authors: Borucki Leonard John , Sun Ting , Zhuang Yun , Slutz David , Philipossian Ara
Published: July 2009

Material removal during CMP occurs by the activation of slurry particles at contact points between pad summits and the wafer. When slurry is present and the wafer is sliding, contacts become lubricated. We present an analysis valid over the full range from static contact to hydroplaning that indicates that CMP usually operates in boundary or mixed lubrication mode at contacts and that the lubrication layer is nanometers thick. The results suggest that the sliding solid contact area is mainly responsible for the friction coefficient while both the solid contact and lubricated areas control the removal rate.
Influence of Chemical-Mechanical Polishing Process on Time Dependent Dielectric Breakdown Reliability of Cu/Low-k Integration
Authors: Yamada Yohei , Konishi Nobuhiro
Published: July 2009

The effects of defects caused by Cu chemical-mechanical polishing (CMP) on time-dependent dielectric breakdown (TDDB) in a damascene structure incorporating a low-k interlevel dielectric layer were investigated experimentally. Comb line capacitor structures were prepared with one of three types of defects (rough Cu surface corrosion, Cu depletion, or crevice corrosion) and stressed at 3.2 to 6.2 MV/cm at 140°C. The first two defects had an insignificant effect on the TDDB characteristics while crevice corrosion at the edges of wires significantly degraded them. Investigation of the effects of Cu oxidation during post-CMP cleaning on the TDDB characteristics revealed that the formation of a non-uniform oxide layer accompanying deionized water rinsing was due to the dissolution of Cu oxide during the post-CMP cleaning process. When a barrier metal slurry containing a soluble inhibitor was used, non-uniform oxide formation on the Cu surfaces during post-CMP cleaning degraded the TDDB characteristics. These results demonstrate the importance of uniform Cu oxidation during post-CMP cleaning for improving the TDDB characteristics.
An Investigation of the Influence of Orientation on CMP through Nanoscratch Testing
Authors: Neyer Sarah , Ozdoganlar Burak , Higgs C. Fred
Published: July 2009

With the increase in integrated circuit (IC) feature density, the quality of chemical mechanical polishing (CMP) becomes more important as the copper interconnects decrease in size. The optimization of the IC manufacturing process will be greatly enhanced if the nanoscale effects on CMP are better understood. CMP-related wear at the sub-micron scale, where a single particle affects the microstructure of individual copper features within the substrate, needs to be investigated to account for wafer-scale variations. Hardness is known to affect the material removal rate, but the grain level mechanism of the removal process is not yet well known. In this work, the orientation-dependence of wear has been investigated by performing nanoscale scratch tests on single crystal copper along different crystallographic planes, indentified using orientation imaging microscopy (OIM). An analysis of the surface forces and post-scratch topography produced during the scratch tests was conducted and the results have been interpreted from a CMP perspective. Ultimately, these results are expected to refine existing material removal rate models which do not consider the sensitivity of microstructure on the CMP process.
Properties of Ti-Si-N Hard Coatings Prepared by Filtered Vacuum Arc Source and Magnetron Sputtering Cathode
Authors: Lee Seunghun , Svadkovski Igor , Kim Jong-Kuk , Kim Do-Geun
Published: July 2009

Ti-Si-N nanocomposite coatings have been investigated using a hybrid coating system. The elimination of macro particles and the control of Si content should be accompanied to realize high quality of coating layer since macro particles induce corrosive reaction and the Si content of Ti-Si-N coating affects the mechanical properties such as hardness and friction coefficient. We introduced the hybrid coating system which consists of double bending filtered vacuum arc system (DBFVAS) and magnetron sputter cathode to solve two problems such as the macro particles and the control of Si content in Ti-Si-N coatings. The DBFVAS and magnetron sputter equipped with Ti cathode and Si cathode target, respectively. Ar and N2 are used for discharge and reaction gas and operating pressure is 0.6 mTorr. We confirmed that the DBFVAS reduced macro particles effectively and the Si content could be changed by controlling the applied power on magnetron sputtering cathode. The properties of Ti-Si-N coating layer are estimated by X-ray diffraction, X-ray photoelectron spectroscopy, wear test and nano indentation. And we compared Si content with Si emission (594.84 nm) of process chamber using an optical emission spectroscopy.
Effect of Shunts on Thin-Film CdTe Module Performance
Authors: Koishiyev Galymzhan T. , Sites James R.
Published: July 2009

A 2-D numerical circuit model is used to analyze the impact of shunts on basic performance parameters of a CdTe thin-film module. A numerical estimate of module-efficiency loss in the worst-case scenario due to shunts of different severity and fractional module area is presented. It is shown that absolute module-efficiency loss Δη (%) varies in systematic fashion with these shunt parameters. Estimates of Δη based on simple area-weighted efficiency are typically low by 3-4 times. Furthermore, the distribution pattern of shunts over the module plays a significant role in the module loss. A reliable parameter P to characterize the distribution of shunts is introduced, and its effect on module-efficiency loss, as well as individual-parameter (FF, VOC and JSC) losses, is shown. Furthermore, higher transparent-conductive-oxide (TCO) sheet resistance is shown to increase shunt isolation and consequently mitigate the efficiency decrease.
Chemically Deposited Silver Antimony Selenide Thin Films for Photovoltaic Applications
Authors: Garza Jorge G. , Shaji Sadasivan , Tovar Ana Maria Arato , Tijerina Eduardo Perez , Roderiguez Alan Castillo , Roy Tushar K Das , Krishnan Bindu
Published: July 2009

Silver antimony selenide (AgSbSe2) thin films were prepared by heating sequentially deposited antimony sulphide (Sb2S3), silver selenide (Ag2Se) and Ag thin films in close contact with a selenium thin film. Sb2S3 thin film was prepared from chemical bath containing SbCl3 and Na2S2O3, Ag2Se from the bath containing AgNO3 and Na2SeSO3 and Se thin films from an acidified solution of Na2SeSO3, at room temperature on cleaned glass substrates. Ag thin film was deposited by vacuum thermal evaporation. The annealing temperature was varied from 300-390°C in vacuum (∼10−3 Torr) for 1 h. X-ray diffraction analysis showed the films formed at 350 °C was polycrystalline AgSb(S,Se)2 or AgSbSe2 depending on selenium thin film thickness. Morphology of these films was analyzed using Atomic Force Microscopy and Scanning Electron Microscopy. The elemental analysis was done using Energy Dispersive X-ray technique. Optical characterization of the thin films was done by optical transmittance spectra. The electrical characterizations were done using Hall effect and photocurrent measurements. A photovoltaic structure: Glass/ITO/CdS/AgSbSe2/Ag was formed, in which CdS was deposited by chemical bath deposition. J-V characteristics of this PV structure showed Voc=370 mV and Jsc=0.5 mA/cm2 under illumination using a tungsten halogen lamp.
Real-Time Spectroscopic Ellipsometry of Sputtered CdTe Thin Films: Effect of Ar Pressure on Structural Evolution and Photovoltaic Performance
Authors: Sestak Michelle Nicole , Li Jian , Paudel Naba Raj , Wieland Kristopher , Chen Jie , Thornberry Courtney , Collins Robert , Compaan Alvin
Published: July 2009

In this study, 1 μm thick polycrystalline CdTe films were deposited by magnetron sputtering using a variable argon pressure, 2.5 ≤ pAr ≤ 50 mTorr, and a fixed substrate temperature, Ts = 230°C. Real time spectroscopic ellipsometry (RTSE) was performed during deposition in order to analyze the nucleation and coalescence, as well as the evolution of the surface roughness thickness ds with bulk layer thickness db and the depth profile in the void volume fraction fv. A linear correlation was found between the final ds value measured by RTSE at the end of deposition and the root-mean-square (rms) surface roughness measured by atomic force microscopy (AFM) ex situ after deposition. A monotonic decrease in RTSE-determined roughness thickness is observed with decreasing Ar pressure from 18 to 2.5 mTorr. The lowest pressure also leads to the greatest bulk layer structural uniformity; in this case, fv increases to 0.04 with increasing CdTe thickness to 1 μm. The photovoltaic performance of CdTe films prepared with the lowest pressure of pAr = 2.5 mTorr is compared with that of previously optimized CdTe solar cells with pAr = 10 mTorr.
Determination of Thermal Parameters of Nanostructures Exhibiting One-Dimensional Heat Flow Through a Thermal Transient Method
Authors: Arriagada Anton , Yu Edward T , Bandaru Prabhakar
Published: July 2009

We present an improved methodology for a thermal transient method enabling simultaneous measurement of thermal conductivity and specific heat of nanoscale structures with one-dimensional heat flow. The temporal response of a sample to finite duration heat pulse inputs for both short (1 ns) and long (5μs) pulses is analyzed and exploited to deduce the thermal properties. Excellent agreement has been obtained between the recovered physical parameters and computational simulations.
Quantitative Structure Analysis of Nano-sized Materials by Transmission Electron Microscopy
Authors: Neumann Wolfgang , Kirmse Holm , Häeusler Ines , Zheng Changlin , Mogilatenko Anna
Published: July 2009

Nanostructured materials from almost all classes of materials are of great interest because the reduced dimensionality may drastically change the physical properties. In general, these properties are a function of size, shape, arrangement and chemical composition of the nano-sized materials. Transmission electron microscopy (TEM) is a powerful tool to get a detailed insight into the material characteristics. To correlate microstructure as well as microchemistry and materials properties the various TEM techniques for imaging, diffraction and spectroscopy have to be combined. The potential applicability of quantitative TEM will be demonstrated for different nano-sized objects, particularly for semiconductor islands, nanowires, quantum dots and for soft magnetic materials. The classical diffraction contrast method of conventional TEM is applied to analyse the size, shape and arrangement of nano-sized structures, where a quantitative analysis often requires image simulations of diffraction contrast for theoretical structure models. An alternative and powerful method is the three-dimensional reconstruction of the shape from two-dimensional phase mapping by means of electron holography. This reqires the exact calculation of the mean inner potential of the specimen. Quantitative high-resolution transmission electron microscopy (qHRTEM) has to be applied to analyse structure and chemical composition on an atomic scale of magnitude. Particularly the application of aberration-corrected HRTEM offers new possibilities for quantitative structure analysis due to a contrast transfer by means of negative spherical aberration imaging (NCSI) and the resulting strong suppression of image delocalisation effects. An example for quantitative composition analysis will be demonstrated for ternary semiconductor quantum structures by means of a combined analysis of dark-field imaging and qHRTEM. The results will be compared with analytical TEM data (energy-dispersive X-ray spectroscopy (EDXS), electron energy-loss spectroscopy (EELS), and energy-filtered TEM (EFTEM)). The retrieval of chemical information with atomic resolution will be illustrated for III-V semiconductor nanostructures using STEM (scanning TEM) Z-contrast imaging. The correlation of structure and magnetic properties of soft magnetic materials will be demonstrated by combined application of Lorentz microscopy and electron holography. The potential applicability of the different quantitative TEM methods will be shown for following systems:

(i) (Si,Ge) islands

(ii) ZnTe and (Zn,Mn)Te nanowires

(iii) Ga(As,Sb) quantum dots (QDs) on GaAs substrate

(iv) nc softmagnetic FeCo alloys

The possibilities and limitations of the various methods applied will be critically evaluated.
Elastic Properties of Nano–Thin Films by Use of Atomic Force Acoustic Microscopy
Authors: Kopycinska-Müller Malgorzata , Striegler Andre , Hürrich Arnd , Köhler Bernd , Meyendorf Norbert , Wolter Klaus Jürgen
Published: July 2009

Atomic force acoustic microscopy (AFAM) is a non-destructive method able to determine the indentation modulus of a sample with high lateral and depth resolution. We used the AFAM technique to measure the indentation modulus of film-substrate systems Msam and then to extract the value of the indentation modulus of the film Mf. The investigated samples were films of silicon oxide thermally grown on silicon single crystal substrates by use of dry and wet oxidation methods. The thickness of the samples ranged from 7 nm to 28 nm as measured by ellipsometry. Our results clearly show that the values of Msam obtained for the film-substrate systems depended on the applied static load and the film thickness. The observed dependency was used to evaluate the indentation modulus of the film. The values obtained for Mf ranged from 77 GPa to 95 GPa and were in good agreement with values reported in the literature.
Amino- and Carboxy-functionalized Nano- and Microstructured Surfaces for Evaluating the Impact of Non-biological Stimuli on Adhesion, Proliferation and Differentiation of Primary Skin-Cells
Authors: Kluger Petra J. , Panas Marc , Schober Lena , Tovar Guenter E. M. , Mertsching Heike , Borchers Kirsten
Published: July 2009

To gain basic insight into the impact of non-biological features on cells’ behaviour, primary skin-cells, keratinocytes and fibroblasts, were cultured on amine-functionalized or carboxy-functionalized planar, nano- or microstructured surfaces. Sintered layers of silica nano- or microparticles were used to fabricate structures in the range of naturally occurring structure-sizes. Organo-chemical functionalization was achieved using organo-functional silanes. Primary human keratinocytes and fibroblasts were isolated from human foreskin and cultivated on the modified interfaces. Both cell-types displayed specific proliferation behaviour, depending on surface topography and chemical functionalization: Keratinocytes showed significantly better proliferation on amino-functionalized surfaces than on carboxy-functionalized surfaces. On amino-functional surfaces decree-topography. Fibroblasts, in contrast, tended to proliferate stronger on carboxylated surfaces. Immunohistological staining proofed that actin and vinculin, which is involved in the formation of focal adhesions, were expressed on all modified surfaces, thus revealing intact cytoskeleton and cell-substrate contacts.
Relationship Between Materials Properties and Shape Memory Behavior in Epoxy-Amine Polymers
Authors: Rousseau Ingrid A , Xie Tao
Published: July 2009

Although epoxy-based polymers remain infrequently used as shape memory polymers (SMP’s), they are a promising base material for highly demanding applications due to their intrinsic physical properties and ease of processing. A series of epoxy SMP’s was synthesized with varying mechanical properties and with glass transition temperatures ranging from 31 to 93 °C, tunable via the variations of the molecular structures. The influence of chemical structures and physical properties of these epoxy SMP’s on their shape memory (SM) behavior is examined in detail along with the impact of the shape memory cycling conditions. While the results show that lower crosslink densities and/or higher molecular flexibility/mobility leads decreased SM performance, at low crosslink density the effect of molecular flexibility/mobility becomes dominant in influencing the SM response.
On Probability Distribution of Hydraulic Conductivity in Variably Saturated Bimodal Heterogeneous Formations
Authors: Russo David
Published: July 2009

First‐order analysis was used to analyze the probability density function (PDF) of the logarithm of conductivity, log K, in variably saturated, bimodal, heterogeneous formations, and to investigate the implications of the results with respect to solute transport. The bimodal formations were viewed as mixtures of two populations (background soil and embedded soil) of differing spatial structures. Two distinct cases were considered: in the first case, the texture of the embedded soil is finer than that of the background soil, while the second case is the reverse situation. Results of this study suggest that, because for a given volume fraction of the embedded soil, both the mean and the variance of log K depend on the mean pressure head, H, in a manner that depends on the texture of the embedded soil relative to that of the background soil, so does the log K PDF. Furthermore, because of the inherent concave behavior of the log K variance–pressure head relationships in these formations, the shape of the bimodal log K PDF may change with increasing H, such that at a certain critical mean pressure head it may degenerate into an “equivalent,” unimodal PDF. One of the main findings of this study suggests that even when the two subdomains of the formation are characterized by mild heterogeneity, a relatively small volume fraction of coarse‐textured embedded soil may lead to a highly skewed log K PDF, which, in turn, may exhibit an exceedingly large tail associated with the small K values, particularly when the contrast between mean conductivities of the two subdomains of the formation at saturation is relatively large and when the formation is relatively dry.
Unsaturated Hydraulic Conductivity Measurements with Centrifuges: A Review
Authors: van den Berg E. H. , Perfect E. , Tu C. , Knappett P. S. K. , Leao T. P. , Donat R. W.
Published: July 2009

Conducting drainage or imbibition experiments in a centrifugal force field has long been recognized as a valid and efficient way to determine capillary pressure–saturation and relative permeability–saturation relationships. Experiments involving multiphase flow of immiscible fluids in porous media are sped up because the centrifugal acceleration is many times greater than Earth's gravitational acceleration. In addition, the fact that centrifugal force is a body force and that experiments can be performed under well‐controlled conditions are considered advantages over other techniques. During the past few decades, transient‐flow centrifuge methods have been developed and applied in petroleum geosciences, while in the soil and environmental sciences the focus has been on steady‐state centrifuge methods. To inform both groups of each others' work, the different instrumental approaches used are described. The theoretical background for modeling multiphase fluid flow of immiscible fluids through porous media in a centrifugal force field is then reviewed. This background forms the basis for understanding analytical and numerical formulations to interpret both steady‐state and transient‐flow centrifuge experiments. Research on the effects of compaction, menisci deformation, boundary conditions, corrections for early‐time production data, the selection of measurable variables, and nonuniqueness of the data interpretation is discussed. A numerical example application of the transient‐flow centrifuge method is presented. Finally, the major conclusions that can be drawn from the literature are discussed and potential areas for future research are identified.
Comparison of Preferential Flow Paths to Bulk Soil in a Weakly Aggregated Silt Loam Soil
Authors: Wuest Stewart B.
Published: July 2009

Preferential flow paths are common in both tilled and untilled soil, but how or why soil in preferential paths differs from neighboring bulk soil is not well understood in either. We used a 10‐min pulse of dye to mark preferential flow paths at the end of 2 h of ponded infiltration. Small cores were taken from dyed and undyed soil at the 10‐ to 25‐cm depth. Compared with the bulk soil, preferential flow zones had more large and fewer small aggregates, greater water content, and lower bulk density (1.20 vs. 1.23 Mg m−3). Root mass and total soil C were not significantly different. In comparison to untilled soil, tilled soil had more unaggregated soil, greater water content, and lower bulk density (1.16 vs. 1.24 Mg m−3). Statistical analysis suggested no interactions between the preferential flow zone–bulk soil factor and the tilled–untilled factor. Infiltration rates in untilled soil were greater despite greater bulk density in both preferential flow zones and the non‐preferential‐flow matrix soil. These results suggest that greater saturated water conductivity in untilled soil is not due to better developed individual preferential flow pathways, but rather to a greater number of potential pathways being well connected to the surface water source. This could have more to do with better aggregation of surface soil than with specific properties of the preferential flow paths.