bluuebunny/crossref_metadata_2025 huggingface dataset:
Keratinocyte PIEZO1 modulates cutaneous mechanosensation
Authors: Mikesell Alexander R , Isaeva Olena , Moehring Francie , Sadler Katelyn E , Menzel Anthony D , Stucky Cheryl L
Published: September 2022

Epidermal keratinocytes mediate touch sensation by detecting and encoding tactile information to sensory neurons. However, the specific mechanotransducers that enable keratinocytes to respond to mechanical stimulation are unknown. Here, we found that the mechanically-gated ion channel PIEZO1 is a key keratinocyte mechanotransducer. Keratinocyte expression of PIEZO1 is critical for normal sensory afferent firing and behavioral responses to mechanical stimuli in mice.
Stage-dependent differential influence of metabolic and structural networks on memory across Alzheimer’s disease continuum
Authors: Ng Kok Pin , Qian Xing , Ng Kwun Kei , Ji Fang , Rosa-Neto Pedro , Gauthier Serge , Kandiah Nagaendran , Zhou Juan Helen ,   Alzheimer's Disease Neuroimaging Initiative
Published: September 2022

Background:

Large-scale neuronal network breakdown underlies memory impairment in Alzheimer’s disease (AD). However, the differential trajectories of the relationships between network organisation and memory across pathology and cognitive stages in AD remain elusive. We determined whether and how the influences of individual-level structural and metabolic covariance network integrity on memory varied with amyloid pathology across clinical stages without assuming a constant relationship.

Methods:

Seven hundred and eight participants from the Alzheimer’s Disease Neuroimaging Initiative were studied. Individual-level structural and metabolic covariance scores in higher-level cognitive and hippocampal networks were derived from magnetic resonance imaging and [18F] fluorodeoxyglucose positron emission tomography using seed-based partial least square analyses. The non-linear associations between network scores and memory across cognitive stages in each pathology group were examined using sparse varying coefficient modelling.

Results:

We showed that the associations of memory with structural and metabolic networks in the hippocampal and default mode regions exhibited pathology-dependent differential trajectories across cognitive stages using sparse varying coefficient modelling. In amyloid pathology group, there was an early influence of hippocampal structural network deterioration on memory impairment in the preclinical stage, and a biphasic influence of the angular gyrus-seeded default mode metabolic network on memory in both preclinical and dementia stages. In non-amyloid pathology groups, in contrast, the trajectory of the hippocampus-memory association was opposite and weaker overall, while no metabolism covariance networks were related to memory. Key findings were replicated in a larger cohort of 1280 participants.

Conclusions:

Our findings highlight potential windows of early intervention targeting network breakdown at the preclinical AD stage.

Funding:

Data collection and sharing for this project was funded by the Alzheimer's Disease Neuroimaging Initiative (ADNI) (National Institutes of Health Grant U01 AG024904) and DOD ADNI (Department of Defense award number W81XWH-12-2-0012). We also acknowledge the funding support from the Duke NUS/Khoo Bridge Funding Award (KBrFA/2019-0020) and NMRC Open Fund Large Collaborative Grant (OFLCG09May0035), NMRC New Investigator Grant (MOH-CNIG18may-0003) and Yong Loo Lin School of Medicine Research funding.
Brain atlas for glycoprotein hormone receptors at single-transcript level
Authors: Ryu Vitaly , Gumerova Anisa , Korkmaz Funda , Kang Seong Su , Katsel Pavel , Miyashita Sari , Kannangara Hasni , Cullen Liam , Chan Pokman , Kuo TanChun , Padilla Ashley , Sultana Farhath , Wizman Soleil A , Kramskiy Natan , Zaidi Samir , Kim Se-Min , New Maria I , Rosen Clifford J , Goosens Ki A , Frolinger Tal , Haroutunian Vahram , Ye Keqiang , Lizneva Daria , Davies Terry F , Yuen Tony , Zaidi Mone
Published: September 2022

There is increasing evidence that anterior pituitary hormones, traditionally thought to have unitary functions in regulating single endocrine targets, act on multiple somatic tissues, such as bone, fat, and liver. There is also emerging evidence for anterior pituitary hormone action on brain receptors in mediating central neural and peripheral somatic functions. Here, we have created the most comprehensive neuroanatomical atlas on the expression of TSHR, LHCGR, and FSHR. We have used RNAscope, a technology that allows the detection of mRNA at single-transcript level, together with protein level validation, to document Tshr expression in 173 and Fshr expression in 353 brain regions, nuclei and subnuclei identified using the Atlas for the Mouse Brain in Stereotaxic Coordinates. We also identified Lhcgr transcripts in 401 brain regions, nuclei and subnuclei. Complementarily, we used ViewRNA, another single-transcript detection technology, to establish the expression of FSHR in human brain samples, where transcripts were co-localized in MALAT1-positive neurons. In addition, we show high expression for all three receptors in the ventricular region—with yet unknown functions. Intriguingly, Tshr and Fshr expression in the ependymal layer of the third ventricle was similar to that of the thyroid follicular cells and testicular Sertoli cells, respectively. In contrast, Fshr was localized to NeuN-positive neurons in the granular layer of the dentate gyrus in murine and human brain—both are Alzheimer’s disease-vulnerable regions. Our atlas thus provides a vital resource for scientists to explore the link between the stimulation or inactivation of brain glycoprotein hormone receptors on somatic function. New actionable pathways for human disease may be unmasked through further studies.
Data-driven, participatory characterization of farmer varieties discloses teff breeding potential under current and future climates
Authors: Woldeyohannes Aemiro Bezabih , Iohannes Sessen Daniel , Miculan Mara , Caproni Leonardo , Ahmed Jemal Seid , de Sousa Kauê , Desta Ermias Abate , Fadda Carlo , Pè Mario Enrico , Dell'Acqua Matteo
Published: September 2022

In smallholder farming systems, traditional farmer varieties of neglected and underutilized species (NUS) support the livelihoods of millions of growers and consumers. NUS combine cultural and agronomic value with local adaptation, and transdisciplinary methods are needed to fully evaluate their breeding potential. Here, we assembled and characterized the genetic diversity of a representative collection of 366 Ethiopian teff (Eragrostis tef) farmer varieties and breeding materials, describing their phylogenetic relations and local adaptation on the Ethiopian landscape. We phenotyped the collection for its agronomic performance, involving local teff farmers in a participatory variety evaluation. Our analyses revealed environmental patterns of teff genetic diversity and allowed us to identify 10 genetic clusters associated with climate variation and with uneven spatial distribution. A genome-wide association study was used to identify loci and candidate genes related to phenology, yield, local adaptation, and farmers’ appreciation. The estimated teff genomic offset under climate change scenarios highlighted an area around lake Tana where teff cropping may be most vulnerable to climate change. Our results show that transdisciplinary approaches may efficiently propel untapped NUS farmer varieties into modern breeding to foster more resilient and sustainable cropping systems.
Learning to unlearn - Tracing Failures Within Arts-Based Participatory Research
Authors: Ulrichsen Gry O.
Published: September 2022

In this article, I trace my own research practice in a process of unlearning from an individual self-reflexive approach. Striving towards a more participatory and collective approach, I turn my attention to relational aspects between people, materials and discourses, and give them a central role in knowledge production as I move and find myself being moved in and out of apparently incommensurable paradigms: the qualitative and the post-qualitative; the humanist and the post-humanist; the post-humanist and the decolonial. I will unpack some of the emerging challenges, tensions and potentials as a becoming researcher pushing against boundaries in a space of conventional academic expectations within my researcher education.
Examining the ability to track multiple moving targets as a function of postural stability: a comparison between team sports players and sedentary individuals
Authors: Zwierko Teresa , Lesiakowski Piotr , Redondo Beatriz , Vera Jesús
Published: September 2022

Background

The ability to track multiple objects plays a key role in team ball sports actions. However, there is a lack of research focused on identifying multiple object tracking (MOT) performance under rapid, dynamic and ecologically valid conditions. Therefore, we aimed to assess the effects of manipulating postural stability on MOT performance.

Methods

Nineteen team sports players (soccer, basketball, handball) and sixteen sedentary individuals performed the MOT task under three levels of postural stability (high, medium, and low). For the MOT task, participants had to track three out of eight balls for 10 s, and the object speed was adjusted following a staircase procedure. For postural stability manipulation, participants performed three identical protocols (randomized order) of the MOT task while standing on an unstable platform, using the training module of the Biodex Balance System SD at levels 12 (high-stability), eight (medium-stability), and four (low-stability).

Results

We found that the ability to track moving targets is dependent on the balance stability conditions (F2,66 = 8.7, p < 0.001, η² = 0.09), with the disturbance of postural stability having a negative effect on MOT performance. Moreover, when compared to sedentary individuals, team sports players showed better MOT scores for the high-stability and the medium-stability conditions (corrected p-value = 0.008, Cohen’s d = 0.96 and corrected p-value = 0.009, Cohen’s d = 0.94; respectively) whereas no differences were observed for the more unstable conditions (low-stability) between-groups.

Conclusions

The ability to track moving targets is sensitive to the level of postural stability, with the disturbance of balance having a negative effect on MOT performance. Our results suggest that expertise in team sports training is transferred to non-specific sport domains, as shown by the better performance exhibited by team sports players in comparison to sedentary individuals. This study provides novel insights into the link between individual’s ability to track multiple moving objects and postural control in team sports players and sedentary individuals.
Satellite remote sensing of environmental variables can predict acoustic activity of an orthopteran assemblage
Authors: Gomez-Morales Diego A. , Acevedo-Charry Orlando
Published: September 2022

Passive acoustic monitoring (PAM) is a promising method for biodiversity assessment, which allows for longer and less intrusive sampling when compared to traditional methods (e.g., collecting specimens), by using sound recordings as the primary data source. Insects have great potential as models for the study and monitoring of acoustic assemblages due to their sensitivity to environmental changes. Nevertheless, ecoacoustic studies focused on insects are still scarce when compared to more charismatic groups. Insects’ acoustic activity patterns respond to environmental factors, like temperature, moonlight, and precipitation, but community acoustic perspectives have been barely explored. Here, we provide an example of the usefulness of PAM to track temporal patterns of acoustic activity for a nocturnal assemblage of insects (Orthoptera). We integrate satellite remote sensing and astronomically measured environmental factors at a local scale in an Andean Forest of Colombia and evaluate the acoustic response of orthopterans through automated model detections of their songs for nine weeks (March and April of 2020). We describe the acoustic frequency range and diel period for the calling song of each representative species. Three species overlapped in frequency and diel acoustics but inhabit different strata: canopy, understory, and ground surface level. Based on the acoustic frequency and activity, we identified three trends: (i) both sampled cricket species call at lower frequency for shorter periods of time (dusk); (ii) all sampled katydid species call at higher frequency for longer time periods, including later hours at night; and (iii) the diel acoustic activity span window seems to increase proportionally with dominant acoustic frequency, but further research is required. We also identified a dusk chorus in which all the species sing at the same time. To quantify the acoustic response to environmental factors, we calculated a beta regression with the singing activity as a response variable and moon phase, surface temperature and daily precipitation as explanatory variables. The response to the moon phase was significant for the katydids but not for the crickets, possibly due to differences in diel activity periods. Crickets are active during dusk, thus the effects of moonlight on acoustic activity are negligible. The response to precipitation was significant for the two crickets and not for the katydids, possibly because of higher likelihood of rain interrupting crickets’ shorter diel activity period. Our study shows how the local survey of orthopteran acoustic assemblages, with a species taxonomic resolution coupled with remote-sensing environmental measurements can reveal responses to environmental factors. In addition, we demonstrate how satellite data might prove to be a useful alternative source of environmental data for community studies with geographical, financial, or other constraints.
Breves reflexiones sobre la presunción de responsabilidad ambiental
Authors:   Universidad Adolfo Ibáñez, Tapia Ferrer Francisco Javier
Published: September 2022

En los últimos años, la jurisprudencia y la doctrina se han esforzado en darle contornos a los institutos jurídicos vinculados con la responsabilidad por daño ambiental, debido a la complejidad de las controversias ambientales. Algunos de estos esfuerzos han estado enfocados en la presunción de responsabilidad regulada en el artículo 52 de la Ley Ambiental. En este artículo, abordamos los elementos básicos de dicha presunción, el rol que ha tenido la jurisprudencia y la doctrina en su configuración y, sobre todo, las dudas que aún persisten sobre esta materia.
Recurso de unificación de jurisprudencia: Procedencia y requisitos de admisibilidad
Authors:   Segundo Juzgado del Trabajo de Santiago, Fuenzalida Martínez Patricia
Published: September 2022

El presente trabajo presenta el recurso de unificación de jurisprudencia establecido en la legislación laboral chilena y analiza el modo en que la jurisprudencia de la Corte Suprema ha interpretado sus presupuestos, destacando los principales elementos que determinan su procedencia y aquellos defectos que pueden impedir un pronunciamiento de fondo.
La lesión de derechos fundamentales en la relación laboral: Una nueva lectura del artículo 485 del Código del Trabajo
Authors:   Universidad de O’Higgins, Salmona Maureira Francisco José
Published: September 2022

El presente trabajo corresponde a un análisis de la forma en que los derechos constitucionales tienen vigencia al interior de las relaciones laborales, conforme al procedimiento de tutela de derechos fundamentales. Se argumenta que la colisión de los derechos constitucionales, y su solución a partir del principio de proporcionalidad, no son la única o adecuada manera de estimar que se produce una lesión de los derechos fundamentales del trabajador.
Descripción y análisis de la Ley 21.431, que Regula el contrato de trabajadores de empresas de plataformas digitales de servicios
Authors:   Pontificia Universidad Católica de Chile, Arab Verdugo Fernando , Frontaura Marzolo María Florencia ,   Pontificia Universidad Católica de Chile
Published: September 2022

El presente trabajo describe los antecedentes y modificaciones introducidas al Código del Trabajo por la Ley 21.431, que regula el contrato de trabajadores de empresas de plataformas digitales, y analiza aspectos centrales de la normativa, como su ámbito de aplicación, la distinción entre trabajadores de plataformas digitales dependientes e independientes, características de los contratos de ambos tipos de trabajadores y las normas comunes aplicables tanto al trabajador de plataformas digitales dependiente como al trabajador de plataformas digitales independiente.
Digital Gastronomy Vision in Traditional Foods
Authors: BARAN Züleyhan
Published: September 2022

Dijital gastronomi, turizmde yaşanan teknolojik gelişmelerden doğan yeni bir kavramdır. Bu kavram gastronomi turizminin sürdürülebilirliğine katkı sağlayabilecek ve gelecek nesillere doğru aktarabilecek nitelikte bir vizyon olarak
değerlendirilmektedir. Bu durum yaşanan teknolojik gelişmelerin gastronomi turizmi kapsamında önem arz eden geleneksel yemeklere nasıl yansıyacağı sorunsalını da beraberinde getirmektedir. Bu çalışma ile dijital gastronomi vizyonunun
geleneksel yemekler üzerinde nasıl bir etkisinin olacağı ve bu vizyon çerçevesinde geleneksel yemeklerin teknolojik gelişmelere nasıl uyum sağlayacağı belirlenmeye çalışılmıştır. Bu kapsamda çalışma, nitel araştırma deseninde ve
derleme olarak kurgulanmıştır. Kavramsal çerçeve için öncelikle yeni nesil mutfak teknolojilerinin hangi konular olduğu tespit edilmiştir. Yeni nesil mutfak teknolojileri konusunun literatürde; dijital gastronomi, gastronomi 4.0,
dijital mutfak, hibrit mutfak, moleküler gastronomi, laboratuvarda üretilen gıdalar, note by note mutfak, yapay zekâlı robotik mutfak, üç boyutlu yazıcı, siber yemek, lüks gastronomi ve yeni nesil restoran başlıkları altında incelendiği
görülmüştür. Konuyla ilgili olduğu düşünülen başlıklara yönelik yapılan literatür taramasında bir tez, üç bildiri, yedi kitap, yirmi altı makale ve ayrıca web sitelerinde konuyla ilgili yazılan dört önemli yayına ulaşılmıştır.
Elde edilen veriler ışığında dijital gastronomi vizyonuna yönelik fütüristik yaklaşımlarda bulunulmuştur. Sonuç olarak dijital gastronomi vizyonunun yeni nesil mutfak teknolojileri sayesinde israfı önleyen, kişiye özel besin değerine
uygun hazırlanmasına olanak sağlayan ve geleneksel tarifleri korumayı hedefleyen sistemler bütünününden oluştuğu anlaşılmıştır. Dijital gastronomi vizyonunun benimsenmesinin, geleneksel yemek ve mutfak kültürü kavramlarının korunmasında
etkin rol oynayacağı ön görülmüştür.
Some Views on Altruism, Egoism, and Benevolence as a Model of Kindness
Authors: YORGANCILAR Serkan
Published: September 2022

Herhangi bir beklenti içerisine girmeden karşılıksız iyilik yapmak anlamında kullanılan özgecilik kavramının tarihi Comte’a kadar uzanmaktadır. Aslında kavramı ilk kullanan isim Comte olarak kabul edilmekle birlikte farklı filozoflarda
Comte öncesinde özgecilik kavramını kullanmıştırlar. Latince alter’den türetilmiş olan altruism, kendinden başkasına herhangi bir fayda ve yarar gözetmeksizin fayda sağlamak olarak tanımlanmıştır. Comte bu tanımla özgeciliği egoizmin
tam zıttı olarak tanımlamıştır. Egoist davranışlar olumsuzlanmış bunun yerine özgeci davranışlar toplumsal yaşamın sürdürülmesi açısından bir zorunluluk olarak görüşmüştür. Oysa egoist davranışların her zaman olumsuz olmadığını
iddia eden düşünürler için ise özgeci davranışlarla egoist davranışların sınırlı da olsa bir kesişim kümesi bulunmaktadır. Özgeci davranışların neleri içerdiği ya da neleri içermediği sosyal bilimciler tarafından tartışılan bir
konudur. Bu kapsamda hayırseverlik ve özgecilik arasında da farklı değerlendirmeler yapılmıştır. Hayırseverliği özgeci davranış olarak kabul edenler olduğu gibi reddedenlerde olmuştur. Bu konuda özellikle Sorokin tarafından yapılan
farklı yorumlar özgeci davranışların kapsamını genişletmesi açısından önemlidir. Modern toplumlarda toplumsal birliğin sağlanması ve sürdürülebilmesi için özgecilik bir değer yargısı olark kabul edilmiştir. Dolayısıyla özgecilik
sadece bireysel bir olgu değil toplumsal bir olgu haline gelmiştir. Araştırmada özgecilik bir iyilik modeli olarak varsayılmış olup başka iyilik modellerinin olduğuda kabul edilmiştir. Her iyiliğin özgeci davranış olarak kabul
edilmediği ancak özgeci davranışın sınırlarının da muğlak olduğu tespit edilmiştir. Ayrıca çalışmada özgecilğin modern insanın tanımlanmasında farklı bir araç olarak kullanıldığı tespit edilmiştir.
A Comparison Essay on Cyprus Foreign Trade Between the Ottoman Tanzimat Period and the Early British Rule
Authors: KAYA Gökhan
Published: September 2022

Kıbrıs'ın Osmanlılar tarafından fethi, Doğu Akdeniz’de hakimiyet kurma isteği ile doğrudan ilgiliydi. Adanın bu stratejik önemine ek olarak ekonomik potansiyelinin gerçekleşmesinin Tanzimat Dönemi'nde (1839-1876) gerçekleştiğini söylemek
mümkündür. Nitekim söz konusu dönemde Tanzimat Dönemi Osmanlı yöneticileri, tarıma dayalı dış ticareti geliştirmek için yeni tarım alanlarının açılması, altyapının iyileştirilmesi ve vergiden muaf tutulması gibi çeşitli önlemler
almıştır. Bu çabalar sonucunda buğday, arpa ve yulaf üretiminde belirli bir artış gözlenmiştir. Bu ürünlerin dışında zeytin ve zeytinyağı üretimine yönelik çeşitli teşvik politikaları izlenilmişse de istenilen sonuçlar elde edilememiştir.
Bunda yetersiz altyapı, çekirge istilaları, ilkel tarım araçlarının kullanılması gibi sorunlar rol oynamıştır. Ada’nın İngiliz hakimiyetini takip eden ilk on yılda ciddi bir tarımsal ve ticari canlanma olmadıği görülmektedir. Bunun
en önemli nedeni, İngiliz sömürge yönetiminin Ada'da idari, sağlık, adli ve fiziki altyapıyı oluşturmaya yönelik çabalara öncelik vermesidir. Nitekim Kıbrıs’ın ekonomik ve dış ticaret hacmi, İngiliz yönetiminin altyapı yatırımları,
tarımsal planlama, banka ve kredi imkanlarının geliştirilmesi, yeni ve ihracat amaçlı ürünlerin yetiştirilmesi gibi nedenlerle 1890'lı yıllardan itibaren ciddi bir artış eğilimi göstermiştir. Bu artış, İngiliz yönetiminin Ada'daki
resmi gazetesi The Cyprus Gazette'de yayınlanan dış ticaret istatistiklerinde ve Ada’yı ziyaret eden seyyahların kaleme aldığı eserlerde belgelenmiştir. Bu çalışmanın amacı Kıbrıs’ın Tanzimat Dönemi Osmanlı idaresi ile İngiliz
idaresi döneminde gerçekleşen dış ticaret faaliyetlerini karşılaştırma girişimidir. Sömürge öncesi ve sonrası Kıbrıs’ın dış ticarette ne türden bir bir gelişme sağladığının araştırılmasının önemi ise bir anlamda hangi saikler ve
süreçlerle sömürgeciliğin iş gördüğünün ortaya konulmasıdır. Ada’nın gerek Tanzimat Dönemi gerekse de İngiliz Dönemi’ndeki dış ticaret rakamları için olabildiğince farklı kaynaklara başvurulmuştur. Bunlar kaynaklar ise XIX yüzyıl
Osmanlı Dönemi’nde ve Erken XX. yüzyılda İngiliz İdaresi döneminde Ada’yı ziyaret seyyahlar, konu hakkında araştırma yapan kişiler ancak özellikle Kıbrıs İngiliz İdaresi’nin resmi gazetesi olan The Cyprus Gazette ile The Colonial
Office List, The Cyprus Blue Book gibi İngiliz resmi kurumların çıkardığı kaynaklardır.
Evaluation of Russia’s Nuclear Weapons Program in Terms of International Nuclear and Commercial Law
Authors: KIRATLI Metin , KANAPİYANOVA Zhuldyz
Published: September 2022

Sovyet Sosyalist Cumhuriyetler Birliği’nin (SSCB) çöküşünden sonra Rusya’ya miras kalan nükleer silah programı sayesinde Moskova yönetimi “nükleer silaha sahip olan ülkeler” listesinde yer almaktadır. Amerika Birleşik Devletleri (ABD)
ile birlikte dünyanın en büyük nükleer silah gücüne sahip olan Rusya, 1949 yılından bu yana nükleer silah programını geliştirmeye devam etmekte ve nükleer caydırıcılık politikasını sürdürmektedir. Çalışmanın temel amacı, geçmişten
günümüze Rusya’nın nükleer silah programını ele alarak, nükleer silah programının hangi aşamada olduğunu tespit ederek, bunun nükleer hukuk ve ticaret hukuku açısından değerlendirmektir. Rusya-ABD rekabeti yeni dünyada silahlanma
yarışını başlatmıştır. Bu rekabet başta Avrupa olmak üzere birçok gelişmiş ülkeyi de etkilemektedir. Avrupa Birliği ticaret birliği üzerine kurulduğu için aslında birliğin hukuku da genelde ticaret hukuku üzerine şekillenmiştir.
Ukrayna Savaşı ve öncesinde 11 Eylül saldırıları sonrası gelişmeler küresel politikayı da ticareti de olumsuz etkilemiştir. Ukrayna Savaşı sırasında hem fosil yakıtlar hem de lojistik hatlarının olumsuz etkisi günümüzde uluslararası
ticaret hukukundan çok devletlerin kendi hukuklarını ön plana çıkarmıştır. Rusya’nın nükleer politikaları kendini koruma içgüdüsüyle yapılıyor olsa da küresel ticareti de etkilemektedir. Nükleer hukuk dünyada barışın güvencesi
olmayı amaçlarken yeni dönemde geleceğe dair varsayımların öngörülememesi bölgesel ittifakları güçlendirmektedir. Bu bağlamda çalışma saldırgan realizm teorisi çerçevesinde incelenerek, uluslararası anarşik sistemde Rusya’nın maksimum
güç elde ederek, askeri kabiliyetini arttırarak ulusal güvenliğini sağlamaya çalıştığı belirlenmiştir. Ayrıca Ukrayna savaşı sonrası ortaya çıkan nükleer enerji güvenliği ve nükleer silah tehdidinin uluslararası nükleer hukuk açısından
değerlendirilmesi de yapılacaktır. Bu tehditlerin bölgesel ve küresel etkisiyle ticaret hukuku açısından ne gibi eksiklikleri veya sonuçları ortaya çıkaracağı da analiz edilecektir.
Audit Committees’ Effectiveness in Tanzania: The Case of Selected Public Authorities in Tanzania
Authors: Millinga Kelvin Clarence , Naho Alexis
Published: September 2022

Audit committees are important parts of an entity’s governance structure which play a significant role in assisting entities in achieving their planned objectives. This study aimed at assessing the factors affecting audit committees’ effectiveness in the selected public authorities in Tanzania specifically Morogoro region. The study used survey research design based on the mixed research approach i.e., both qualitative and quantitative research approaches were used. A multistage sampling technique were used to select 120 representative respondents for this study. Both primary and secondary data were collected using questionnaires and documentary review respectively. The Logit regression model was used in this study in examining the factors affecting the auditing committees (AC) effectiveness. Also, the maximum likelihood method using SPSS 25 was used to estimate the coefficients of the specified logistic regression model. The study result from logit regression analysis revealed that independence and number of meetings of AC members were statistically significant and positively related to effectiveness of AC while age and gender of the audit committee members were significant but negatively related. Moreover, education level, size of AC and expertise were not statistically significant but positively related to dependent variable. Therefore, for the aim of attaining effective performance of the audit committee in the stated public bodies in Tanzania, it is very vital to take into account the contributions of the determining factors.
Anti-Fungal efficacy of Probiotics in Heat Cure Dentures Base Resin: An In-vitro Study
Authors: Shankar R. Kirupa , Balaji Hemamalini , Shanmuganathan N. , Parthasarathy N. , Athiban I. , Thirumalaikumaran R.
Published: September 2022

Aim: To assess if probiotics alter the adherence of candida species onto the denture base material made with Polymethylmethaacrylate(PMMA).

Materials and Methods: Sample number of 10 per denture base resin with Sample dimensions of length 10 mm × 10 mm and width 2 mm.

Test Group: PMMA samples coated with probiotics at varying concentrations dipped in saliva Containing candida species.

Control Group: PMMA samples in saliva containing candidal species without probiotics.

Results: Significant difference of candida cell count on PMMA was evident before and after giving probiotic. On the heat cure denture base materials, there was a significant decrease in Candidal cell counts when the probiotic concentrations (2.5, 5, 10, 15 and 20 µg/ml) increased.
Heat‐Induced Translocation of Cytoplasmic β‐Galactosidase across Inner Membrane of Escherichiacoli
Authors: Umakoshi Hiroshi , Kuboi Ryoichi , Komasawa Isao , Tsuchido Tetsuaki , Matsumura Yoshinobu
Published: July 2002

The behaviors of heat‐induced translocation of cytoplasmic β‐galactosidase to periplasm across the inner membrane of Escherichia coli cells were investigated in order to apply such phenomena to the process for production and separation of intracellular biomolecules. The heat stress was found to induce translocation of cytoplasmic β‐galactosidase (β‐gal) together with reduction of the amounts of intracellular soluble proteins and formation of their inactive aggregates. The translocation of β‐gal was then analyzed using (a) the location factor of β‐gal (LFG), which meant enzyme location in the cells and could be determined from the kinetic analysis of enzyme release process, and (b) the percentage of β‐gal activity in periplasm after solublizing the outer membrane of E. coli cells by lysozyme/EDTA treatment. The LFG values were maximized when cells were stressed at the temperature of 42–47 °C. From the results on the surface properties of both β‐gal and cell membrane under the heat stress, it is suggested that (1) the conformational change of cytoplasmic oligomeric β‐gal to the partially dissociated and/or unfolded state with higher local hydrophobicity, (2) the increase in membrane fluidity of inner membrane, (3) the enhancement of hydrophobic interaction between lipid and protein, and (4) the inhibition of its translocation by GroEL restabilizing the proteins could underlie the heat‐induced translocation of β‐gal across the inner membrane. The possibility to apply the heat‐induced translocation of β‐gal for the enhancement of the target selectivity at the process upstream is finally presented.
Peroxisome-proliferator-activated receptor-α (PPARα) deficiency leads to dysregulation of hepatic lipid and carbohydrate metabolism by fatty acids and insulin
Authors: SUGDEN Mary C. , BULMER Karen , GIBBONS Geoffrey F. , KNIGHT Brian L. , HOLNESS Mark J.
Published: July 2002

The aim of the present study was to determine whether peroxisome-proliferator-activated receptor-α (PPARα) deficiency disrupts the normal regulation of triacylglycerol (TAG) accumulation, hepatic lipogenesis and glycogenesis by fatty acids and insulin using PPARα-null mice. In wild-type mice, hepatic TAG concentrations increased (P<0.01) with fasting (24h), with substantial reversal after refeeding (6h). Hepatic TAG levels in fed PPARα-null mice were 2.4-fold higher than in the wild-type (P<0.05), increased with fasting, but remained elevated after refeeding. PPARα deficiency also impaired hepatic glycogen repletion (P<0.001), despite normal insulin and glucose levels after refeeding. Higher levels of plasma insulin were required to support similar levels of hepatic lipogenesis de novo (3H2O incorporation) in the PPARα-null mice compared with the wild-type. This difference was reflected by corresponding changes in the relationship between plasma insulin and the mRNA expression of the lipogenic transcription factor sterol-regulatory-element-binding protein-1c, and that of one of its known targets, fatty acid synthase. In wild-type mice, hepatic pyruvate dehydrogenase kinase (PDK) 4 protein expression (a downstream marker of altered fatty acid catabolism) increased (P<0.01) in response to fasting, with suppression (P<0.001) by refeeding. Although PDK4 up-regulation after fasting was halved by PPARα deficiency, PDK4 suppression after refeeding was attenuated. In summary, PPARα deficiency leads to accumulation of hepatic TAG and elicits dysregulation of hepatic lipid and carbohydrate metabolism, emphasizing the importance of precise control of lipid oxidation for hepatic fuel homoeostasis.
Kerr rotation enhancement in metallic bilayer thin films for magneto-optical recording
Authors: Reim W. , Weller D.
Published: July 2002

The enhancement of the magneto-optical Kerr effect via metallic bilayer structures is demonstrated for magneto-optic square loop materials on top of optically thick silver and copper reflectors, respectively. We show that in general an enhancement of the polar Kerr rotation angle θK occurs at photon energies where the optical constants n and k of the reflector have low values. The enhancement factor depends on the thickness of the magnetic layer and on the relative magnitude of the optical constants of both layers. The reflectivity of these bilayer structures is only slightly reduced compared to the bulk magneto-optical medium.
Chemical vapor deposition of cobalt silicide
Authors: West G. A. , Beeson K. W.
Published: July 2002

We have deposited polycrystalline cobalt silicide films by chemical vapor deposition using Co2(CO)8 or HCo(CO)4 as the Co source and SiH4 or Si2H6 as the Si source. The Co:Si ratio of the films is controlled by changing the deposition temperature, and CoSi2 stoichiometry is obtained at 300 °C using SiH4 or at 225 °C when Si2H6 is the Si precursor. Carbon or oxygen contamination of the films is <0.5 at. % at deposition temperatures above 200 °C. Resistivities of films deposited near CoSi2 stoichiometry are typically 200 μΩ cm and drop to 40 μΩ cm upon annealing at 900 °C.
Subpicosecond photoluminescence from radiation-damaged Ga0.47In0.53As
Authors: Höpfel R. A. , Sawaki N. , Wintner E.
Published: July 2002

The luminescence of photoexcited carriers far above the band gap of Ga0.47In0.53As is studied with subpicosecond time resolution. In undamaged material the luminescence decays with characteristic times of 2–4 ps in the energy range between 1.9 and 1.4 eV, due to the rapid energy relaxation of electrons and holes far above the band edges. In radiation-damaged (He+ bombarded) material, luminescence decay times as short as 0.9 ps are observed. The luminescence spectra give evidence for extreme nonequilibrium distributions of the photoexcited carriers, caused by the ultrafast recombination, which—in radiation-damaged samples—is a faster process than energy relaxation.
Nanosecond optical quenching of photoconductivity in a bulk GaAs switch
Authors: Mazzola M. S. , Schoenbach K. H. , Lakdawala V. K. , Ko S. T.
Published: July 2002

Persistent photoconductivity in copper-compensated, silicon-doped semi-insulating gallium arsenide with a time constant as large as 30 μs has been excited by sub-band-gap laser radiation of photon energy greater than 1 eV. This photoconductivity has been quenched on a nanosecond time scale by laser radiation of photon energy less than 1 eV. The proven ability to turn the switch conductance on and off on command, and to scale the switch to high power could make this semiconductor material the basis of an optically controlled pulsed-power closing and opening switch.
Nonresonant electron and hole tunneling times in GaAs/Al0.35Ga0.65As asymmetric double quantum wells
Authors: Nido M. , Alexander M. G. W. , Rühle W. W. , Schweizer T. , Köhler K.
Published: July 2002

Nonresonant carrier tunneling is investigated by time-resolved and time-averaged optical methods for a series of samples with various barrier thicknesses. The electron tunneling times decrease exponentially with the decrease of barrier thickness from 8 to 3 nm, and the trend is well described by a semiclassical model. Additional efficient hole tunneling is observed in the 3 nm barrier sample, and the time constant is of the order of 50 ps.
Optically induced electromagnetic radiation from semiconductor surfaces
Authors: Zhang X.-C. , Darrow J. T. , Hu B. B. , Auston D. H. , Schmidt M. T. , Tham P. , Yang E. S.
Published: July 2002

Ultrafast electromagnetic radiation induced by a femtosecond laser beam from a semiconductor provides determination of the impurity doping concentration, carrier mobility, sign, and strength of the depletion field near the semiconductor surface.
Thermal modeling of continuous-wave end-pumped solid-state lasers
Authors: Innocenzi M. E. , Yura H. T. , Fincher C. L. , Fields R. A.
Published: July 2002

In order to estimate deleterious effects caused by heating in continuous-wave end-pumped solid-state lasers, the heat equation has been solved for an axially heated cylinder with a thermally conductive boundary at the periphery. Steady-state thermal profiles are developed using both a full numerical solution and an analytic approximation which assumes only radial heat flow. The analytic solution, which is in good agreement with the numerical solution, is utilized to obtain an expression for the thermal focusing due to temperature-induced refractive index changes. For Nd:YAG, 1 W of pump power deposited as heat is predicted to cause a thermal focusing length comparable to the cavity length of a typical diode end-pumped laser.
H− production from a barium converter with different discharge configurations
Authors: van Os C. F. A. , Leung K. N. , Kunkel W. B.
Published: July 2002

The production of H− ions at a barium converter immersed in a hydrogen plasma has been investigated experimentally for a pulsed discharge. It is found that the scaling of the negative ion output with incident positive ion current on the converter depends greatly on the actual geometry of the plasma generator. A less than linear scaling is observed in a multicusp system. A more than linear scaling is obtained in a configuration where the filament and the converter are separated by a permanent magnet filter.
Low-temperature reordering in partially amorphized Si crystals
Authors: Priolo Francesco , Battaglia Anna , Nicotra Ruggero , Rimini Emanuele
Published: July 2002

The annealing behavior of the damage produced in Si single crystals by 150 keV Au implants at ∼2×1013 ions/cm2 and at substrate temperatures of 77 K (LN2T) and 300 K, room temperature (RT), has been investigated. The annealing kinetics has been studied in the temperature range between 493 and 623 K and for times up to 2 h. Data have demonstrated that, at a fixed temperature some damage anneals out fast and then a saturation occurs for both the LN2T and RT-damaged samples. This behavior has been tentatively interpreted assuming that the damage is mainly composed by amorphous-like material and that reordering is initiated at preferential growth sites present at nonplanar crystal-amorphous interfaces.
Heterodyne measurement of poling transient effects in electro-optic polymer thin films
Authors: Valley J. F. , Wu J. W. , Valencia C. L.
Published: July 2002

We examine the linear electro-optic response of a polymer thin film to an applied step function poling electric field. Time-resolved measurement of the electro-optic response is compared to theory. The electro-optic response measurement uses a heterodyne interferometric technique not previously reported. Response rise and fall times of the order of milliseconds are resolvable and the temperature dependence of those times reported. Good qualitative agreement between theory and data is presented.
Ultrafast initial relaxation of hot electrons and holes in tetrahedral semiconductors via deformation potential interaction: Theory and experiment
Authors: Zollner Stefan , Gopalan Sudha , Garriga Miquel , Humlíček Josef , Viña Luis , Cardona Manuel
Published: July 2002

The broadenings of the E1 and E1+Δ1 interband critical points can be understood as lifetime effects due to the ultrafast relaxation of the photoexcited hot holes. The contributions to these broadenings arising from the electrons in the conduction band are small, as intervalley scattering times are rather long. We have measured such broadenings in Si, Ge, α-tin, AlAs, AlSb, GaP, GaAs, GaSb, InP, InAs, and InSb with spectroscopic ellipsometry and compare them with calculations based on the deformation potential-type electron-phonon interaction in the rigid pseudo-ion approximation.
Orientation independence of heterojunction-band offsets at GaAs-AlAs heterointerfaces characterized by x-ray photoemission spectroscopy
Authors: Hirakawa K. , Hashimoto Y. , Ikoma T.
Published: July 2002

We systematically studied the orientation and the growth sequence dependence of the valence-band offset ΔEv at the lattice-matched common anion GaAs-AlAs interfaces. High quality GaAs-AlAs heterojunctions were carefully grown on GaAs substrates with three major orientations, namely, (100), (110), and (111)B. The core level energy distance ΔECL between Ga 3d and Al 2p levels was measured by in situ x-ray photoemission spectroscopy. ΔECL is found to be independent of the substrate orientation and the growth sequence, which clearly indicates the face independence of ΔEv. This result suggests that the band lineup at lattice-matched isovalent semiconductor heterojunctions is determined by the bulk properties of the constituent materials. ΔEv is determined to be 0.44 ± 0.05 eV.
Epitaxy of (100) Cu on (100) Si by evaporation near room temperatures: In-plane epitaxial relation and channeling analysis
Authors: Chang Chin-An , Liu Joyce C. , Angilello Joseph
Published: July 2002

The epitaxial growth of (100) Cu on (100) Si reported recently using evaporation is analyzed to determine the epitaxial relation between Cu and Si, and also the crystalline quality of the Cu films. A 45° rotation between the (100) plane of Cu and that of Si around their (001) axis is shown to be needed for the lattice match. Such an epitaxial relation is confirmed by the grazing angle x-ray diffraction, with the [010] of Cu parallel to the [011] of Si. The channeling analysis of a 2-μm-thick Cu film shows a 10% minimum near the surface.
K-shell x-ray emission from sodium wire array implosions as the pump for the sodium-neon x-ray laser scheme
Authors: Deeney C. , Nash T. , Prasad R. R. , Warren L. , Apruzese J. P.
Published: July 2002

A technique to extrude pure sodium wires has been developed and this has allowed the implosion of sodium wire arrays on the 4 MA, 6 TW Double Eagle generator. A maximum K-shell x-ray yield of 35 kJ was achieved. Of particular interest, as regards the sodium-neon x-ray laser scheme, is the measured 150 GW, 8 kJ in the NaX 1s2–1s2p 1P line at 11.0027 Å.
Elimination of laser prepulse by relativistic guiding in a plasma
Authors: Sprangle P. , Zigler A. , Esarey E.
Published: July 2002

A method is proposed for eliminating prepulses associated with high-power ultrashort laser pulses. In this method the high-power portion of the pulse is refractively guided due to relativistic effects associated with the plasma electrons. The low-power prepulse, however, is unaffected and diffracts away. Optical guiding is achieved by appropriately choosing the plasma density, laser power, and wavelength. In addition, a wavebreaking stabilization mechanism for the Raman backscattering instability for intense laser pulses is proposed, which indicates that the pulse should not be significantly backscattered by the plasma.
Laser-assisted micron scale particle removal
Authors: Imen K. , Lee S. J. , Allen S. D.
Published: July 2002

A novel laser-assisted particle removal (LAPR) technique capable of removing micron scale particles from semiconductor substrates is presented. In our preliminary experiments the contaminated substrates were dosed with water which preferentially adsorbs in the capillary spaces under and around the particles and were subsequently irradiated with transverse, electric, atomspheric CO2 laser pulses. At the CO2 laser wavelength the beam energy is mainly absorbed in the water and not the substrate. The subsequent explosive evaporation of the adsorbed water molecules produces forces many orders of magnitude larger than the adhesion forces between the particle and the substrate which propel the particles off the substrate surface. LAPR is inherently clean and can easily be incorporated into current or planned wafer processing systems.
Efficient pulsed laser removal of 0.2 μm sized particles from a solid surface
Authors: Zapka W. , Ziemlich W. , Tam A. C.
Published: July 2002

Laser cleaning with pulsed ultraviolet and infrared lasers is successfully employed to remove particulate contamination from silicon wafer surfaces and from delicate lithography membrane masks. Particulate material investigated include latex, alumina, silicon, and gold. Gold particles as small as 0.2 μm can be effectively removed. This new and highly efficient laser cleaning is achieved by choosing a pulsed laser with short pulse duration (without causing substrate damage), and a wavelength that is strongly absorbed by the surface; the removal efficiency is further enhanced by depositing a liquid film of thickness on the order of micron on the surface just before the pulsed laser irradiation.
Molecular beam epitaxy of ZnSe1−xTex ternary alloys
Authors: Turco-Sandroff F. S. , Nahory R. E. , Brazil M. J. S. P. , Martin R. J. , Gilchrist H. L.
Published: July 2002

ZnSe1−xTex ternary alloy has been grown over the entire range of composition by molecular beam epitaxy on GaAs and InP substrates. A precise control of the composition is achieved by growing this material under Zn-rich conditions. For low Te concentrations, However, significant Te surface segregation is observed, which may be due to surface energy minimization. The band-gap energy has been measured over the entire range of composition and presents a very strong bowing with a minimum energy of 2.05 eV for a Te concentration of 0.65.
Femtosecond refractive-index spectral hole burning in intrinsic and doped GaAs
Authors: Gong T. , Mertz P. , Nighan W. L. , Fauchet P. M.
Published: July 2002

The temporal and spectral dependence of carrier-induced changes of the refractive index in intrinsic, n-type and p-type GaAs samples is measured using femtosecond pump and continuum-probe techniques. We observe, for the first time, a refractive-index spectral hole burning arising from a nonthermal carrier distribution generated around the initial excited states. Such spectral hole burning is not present within our time resolution in the n-type sample when the injected carrier density is low. The extremely fast initial scattering time in the presence of cold electrons is attributed to relaxation through the emission of phonon-plasmon coupled modes.
Ferroelectric PbZr0.2Ti0.8O3 thin films on epitaxial Y-Ba-Cu-O
Authors: Ramesh R. , Inam A. , Chan W. K. , Tillerot F. , Wilkens B. , Chang C. C. , Sands T. , Tarascon J. M. , Keramidas V. G.
Published: July 2002

We have fabricated epitaxial ferroelectric PbZr0.2Ti0.8O3/YBa2Cu3O7−x heterostructures on single crystalline [001] LaAlO3. Only the (00l) peaks of the PbZr0.2Ti0.8O3 (PZT) film are observed, indicating that the epitaxial, c-axis oriented YBCO film is a good structural template for the heteroepitaxial growth of PZT films, in addition to being a metallic bottom electrode. A saturation polarization and remanence as high as 38 and 26.5 μC/cm2 (at 7.5 V, 0.5 kHz), respectively, have been achieved. The coercive field is about 100 kV/cm.
Threshold reduction in strained InGaAs single quantum well lasers by rapid thermal annealing
Authors: Yamada N. , Roos G. , Harris J. S.
Published: July 2002

A significant reduction in lasing threshold is achieved by rapid thermal annealing (RTA) for strained InGaAs/GaAs single quantum well lasers grown by molecular beam epitaxy under standard conditions (the growth temperature is 620 °C or less), not especially optimized for lasers. When RTA at 900 °C for 10 s is applied twice to the wafer after the growth, the room-temperature photoluminescence efficiency of the active layer increases by about 80 times and the threshold current decreases by a factor of 5 to 7. We suggest that this enhancement is due to improvement of the quality of the InGaAs quantum well rather than that of the AlGaAs cladding layers.
Recombination at clean and decorated misfit dislocations
Authors: Radzimski Z. J. , Zhou T. Q. , Buczkowski A. , Rozgonyi G. A. , Finn D. , Hellwig L. G. , Ross J. A.
Published: July 2002

The electrical activity of interfacial misfit dislocations in silicon has been examined using the electron beam induced current technique in a scanning electron microscope. Clean dislocations formed during high-temperature Si(Ge) chemical vapor epitaxy were studied. These defects were subsequently decorated with known metallic impurities (Au and Ni) by diffusion at different temperatures from a backside evaporated layer. Differences in electrical activity are discussed in relation to the detection limits of electron beam induced current technique and energy levels anticipated for the clean or decorated dislocations.