bluuebunny/crossref_metadata_2025 huggingface dataset:
Why don't all maths teachers use dynamic geometry software in their classrooms?
Authors: Stols Gerrit , Kriek Jeanne
Published: April 2016

In this exploratory study, we sought to examine the influence of mathematics teachers' beliefs on their intended and actual usage of dynamic mathematics software in their classrooms. The theory of planned behaviour (TPB), the technology acceptance model (TAM) and the innovation diffusion theory (IDT) were used to examine the influence of teachers' attitudes, subjective norms and perceived behavioural control on their intention to use dynamic mathematics software in their classrooms. The study adopted the co-relational research design, with both correlation statistics and regression analysis used to analyse the data. By using stepwise regression analysis, it was possible to identify the most important belief predictors and their weights for the different constructs. The results were verified by the use of partial least squares. This study found that beliefs about the perceived usefulness and beliefs about their level of technological proficiency are the most important predictors of teachers' intended and actual usage of the software. In this preliminary study the suggested simplified model sufficiently explains 15 (83.3%) of the 18 teachers adaption and use of dynamic mathematics software in their classrooms.
Integrating online learning in NSW secondary schools: Three schools' perspectives on ICT adoption
Authors: Neyland Edwina
Published: April 2016

This report examines factors associated with integration of online learning in Sydney region high schools. Past studies have shown that schools can be identified as operating at a certain level of use - ranging from non-use, through stages such as entry, and adaptation, arriving at transformation - when a focus on technology shifts to a focus on the learner. This report highlights several factors affecting the use of online learning in Sydney high schools, including systemic factors such as institutional support, as well as micro factors such as teacher capability. After questionnaires and interviews conducted with computer coordinators during 2009, it was found that immediate school factors such as school support and focus on pedagogy were perceived as being more important than broader systemic factors.
Collab-Analyzer: An environment for conducting web-based collaborative learning activities and analyzing students’ information-searching behaviors
Authors: Wu Chih-Hsiang , Hwang Gwo-Jen , Kuo Fan-Ray
Published: April 2016

Researchers have found that students might get lost or feel frustrated while searching for information on the Internet to deal with complex problems without real-time guidance or supports. To address this issue, a web-based collaborative learning system, Collab-Analyzer, is proposed in this paper. It is not only equipped with a collaborative mechanism for helping group members solve problems on the web, but also facilitates teachers and researchers in analyzing students’ collaborative information-searching behaviors and performance by providing eighteen quantitative indices. To examine the effectiveness of the proposed learning system, a total of 224 university students and 16 teachers participated in an experiment, in which a web-based problem-solving activity for a social studies course was conducted. The experimental results show that the teachers gave positive evaluations of Collab-Analyzer in terms of promoting students' web-based problem-solving ability and information searching skills. Moreover, the students showed high agreement with both the usefulness and ease of use of the system. The research findings also show that high interactive type students have more significant learning performance than moderate and low interactive students. Finally, implications and suggestions for how to accommodate the needs of students after adopting the proposed Collab-Analyzer system are given.
Walk the talk: Immersing pre-service teachers in the learning of ICT tools for knowledge creation
Authors: Divaharan Shanti , Lim Wei-Ying , Tan Seng-Chee
Published: April 2016

This paper traces the evolution of the design framework for the use of technology in a teacher education program in a Singaporean university. This course focuses on developing student teachers' capacity for the use of ICT in teaching and learning. We report our two-level reflection: one that focuses on the trajectory of the course design, and one that reflects on the university faculty's pedagogical practices when conducting this course. The goal of this course in the last decade has transformed from a focus on technology skills to pedagogical and knowledge creation. The current goal of the course is to develop student teachers' pervasive use of technology tools to collaborate, design, reflect and think critically. The challenge for the faculty in a teacher education higher learning institute is to design a course that would present opportunities for student teachers to experience the technology tools as learners themselves so as to become teachers who will be doyens in designing technology tool integrated learning. We contend that the experiences of technology tools help to deepen the student teachers' knowledge about technology integration. As student teachers experience technology tools in tandem with theory, the immersive experience may translate into designing apt technology-integrated lessons for their learners.
A novel method for automatically locating the pylorus in the wireless capsule endoscopy
Authors: Zhou Shangbo , Yang Han , Siddique Muhammad Abubakar , Xu Jie , Zhou Ping
Published: April 2016

Wireless capsule endoscopy (WCE) is a non-invasive technique used to examine the interiors of digestive tracts. Generally, the digestive tract can be divided into four segments: the entrance; stomach; small intestine; and large intestine. The stomach and the small intestine have a higher risk of infections than the other segments. In order to locate the diseased organ, an appropriate classification of the WCE images is necessary. In this article, a novel method is proposed for automatically locating the pylorus in WCE. The location of the pylorus is determined on two levels: rough-level and refined-level. In the rough-level, a short-term color change at the boundary between stomach and intestine can help us to find approximately 70–150 positions. In the refined-level, an improved Weber local descriptor (WLD) feature extraction method is designed for gray-scale images. Compared to the original WLD calculation method, the method for calculating the differential excitation is improved to give a higher level of robustness. A K-nearest neighbor (KNN) classifier is incorporated to segment these images around the approximate position into different regions. The proposed algorithm locates three most probable positions of the pylorus that were marked by the clinician. The experimental results indicate that the proposed method is effective.
Different performances of CXCR4, integrin-1β and CCR-2 in bone marrow stromal cells (BMSCs) migration by low-intensity pulsed ultrasound stimulation
Authors: Xiao Weixiong , Xu Qian , Zhu Zhimin , Li Lei , Chen Wenchuan
Published: April 2016

Low-intensity pulsed ultrasound (LIPUS) is an established therapy for fracture healing where bone marrow stromal cells (BMSCs) migration is crucial to bone regeneration. This work focused on different performances of C-X-C-receptor 4 (CXCR4), integrin-1β and chemokine-chemokine receptor2 (CCR-2) in BMSCs migration by LIPUS stimulation. Single 20-min LIPUS treatment was applied to BMSCs during wound healing assay with or without the inhibitor AMD3100. The migration rate of BMSCs with LIPUS stimulation exhibited a higher closure rate than that of BMSCs without LIPUS stimulation, which was 1.89 μm/h and 1.38 μm/h, respectively. After LIPUS stimulation, significant elevation of the expression of CXCR4, integrin-1β and CCR-2 was observed. When AMD3100 was added, the migration rate of the BMSCs was obviously declined with or without LIPUS treatment. Furthermore, the expression of CXCR4 was significantly down-regulated by AMD3100, while integrin-1β and CCR-2 were less affected. It suggested that the enhancement of the migration of the BMSCs by LIPUS was inhibited by AMD3100. The results confirmed that LIPUS stimulation was able to activate and improve migration of BMSCs. Nevertheless, CXCR4 and both integrin-1β and CCR-2 had different roles in BMSCs migration after LIPUS treatment.
Hyaluronic acid-modified zirconium phosphate nanoparticles for potential lung cancer therapy
Authors: Li Ranwei , Liu Tiecheng , Wang Ke
Published: April 2016

Novel tumor-targeting zirconium phosphate (ZP) nanoparticles modified with hyaluronic acid (HA) were developed (HA-ZP), with the aim of combining the drug-loading property of ZP and the tumor-targeting ability of HA to construct a tumor-targeting paclitaxel (PTX) delivery system for potential lung cancer therapy. The experimental results indicated that PTX loading into the HA-ZP nanoparticles was as high as 20.36%±4.37%, which is favorable for cancer therapy. PTX-loaded HA-ZP nanoparticles increased the accumulation of PTX in A549 lung cancer cells via HA-mediated endocytosis and exhibited superior anticancer activity
Laboratory testing in monoclonal gammopathy of renal significance (MGRS)
Authors: Leung Nelson , Barnidge David R. , Hutchison Colin A.
Published: April 2016

Recently, monoclonal gammopathy of renal significance (MGRS) reclassified all monoclonal (M) gammopathies that are associated with the development of a kidney disease but do not meet the definition of symptomatic multiple myeloma (MM) or malignant lymphoma. The purpose was to distinguish the M gammopathy as the nephrotoxic agent independent from the clonal mass. The diagnosis of MGRS obviously depends on the detection of the M-protein. More importantly, the success of treatment is correlated with the reduction of the M-protein. Therefore, familiarity with the M-protein tests is a must. Protein electrophoresis performed in serum or urine is inexpensive and rapid due to automation. However, poor sensitivity especially with the urine is an issue particularly with the low-level M gammopathy often encountered with MGRS. Immunofixation adds to the sensitivity and specificity but also the cost. Serum free light chain (sFLC) assays have significantly increased the sensitivity of M-protein detection and is relatively inexpensive. It is important to recognize that there is more than one assay on the market and their results are not interchangeable. In addition, in certain diseases, immunofixation is more sensitive than sFLC. Finally, novel techniques with promising results are adding to the ability to identify M-proteins. Using the time of flight method, the use of mass spectrometry of serum samples has been shown to dramatically increase the sensitivity of M-protein detection. In another technique, oligomeric LCs are identified on urinary exosomes amplifying the specificity for the nephrotoxic M-protein.
Preoperative serum potassium predicts the clinical outcome after non-cardiac surgery
Authors: Arora Pradeep , Pourafkari Leili , Visnjevac Ognjen , Anand Edwin J. , Porhomayon Jahan , Nader Nader D.
Published: April 2016

Background:

Potassium disorders have been linked to adverse outcomes in various medical conditions. However, the association of preoperative serum potassium with postoperative outcome is not well established. We aimed to examine the association between preoperative potassium with a 30-day mortality and adverse cardiovascular event (MACE).

Methods:

We conducted a cohort study using a prospectively collected database of patients, undergoing surgical procedures from 1998 to 2013 in the VA Western New York Healthcare System, which are reported to the Veterans Affairs Surgical Quality Improvement Program (VASQIP). The patients were categorized into three groups based on their documented preoperative potassium concentrations. Hypokalemia was defined as serum potassium concentration <4 mmol/L and hyperkalemia was defined as serum potassium concentrations >5.5 mmol/L. The values within the range of 4.0–5.5 mmol/L were considered as normokalemia and used as the control group. Statistical analyses included Chi-square test, analysis of variance and multivariate logistic regression to estimate the risk of MACE within 30 days of surgery.

Results:

Study included 5959 veterans who underwent surgery between 1998 and 2013. The patients in the hyperkalemics group had lower kidney function compared to the other two groups. The frequency of MACE was 13.6% in hypokalemics and 21.9% in hyperkalemics that were both significantly higher than 4.9% in controls. In multivariate logistic regression the hazard risk (HR) ratios of MACE were (2.17, 95% CI 1.75–2.70) for hypokalemics and (3.23, 95% CI 2.10–4.95) for hyperkalemics when compared to normokalemic controls.

Conclusions:

Preoperative hypokalemia and hyperkalemia are both independent predictors of MACE within 30 days.
Synthesis, in-vitro cytotoxicity of 4H-benzo[h]chromene derivatives and structure–activity relationships of 4-aryl group and 3-, 7-positions
Authors: El-Agrody Ahmed M. , Abd El-Mawgoud Heba K. , Fouda Ahmed M. , Khattab Essam S. A. E. H.
Published: April 2016

A series of 2-amino-4
Alkyl glycosides as potential anti-Candida albicans growth agents
Authors: Klunda Tomáš , Machová Eva , Čížová Alžbeta , Horák Radim , Poláková Monika , Bystrický Slavomír
Published: April 2016

infections are becoming increasingly prevalent and many clinical isolates are resistant to common azole derivatives treatment. Accordingly, the capacity of a series of 19 alkyl glycosides, mainly mannosides and glucosides but also a cellobioside with aglycone chain-length from C-6 to C-20, to inhibit the growth of laboratory and clinically isolated strains of
Syntheses of cardanol-based cationic surfactants and their use in emulsion polymerisation
Authors: Wang Rui , Luo Yuna , Cheng Chuan-Jie , Huang Qing-Hua , Huang Hua-Shan , Qin Shuang-Lin , Tu Yuan-Ming
Published: April 2016

Six quaternary ammonium salts were designed and synthesised with moderate to high yields in three steps, based on cardanol, a low-cost and abundant renewable resource. The new ammonium salts can act as reactive surfactants due to their having both a hydrophilic ammonium group and a hydrophobic unsaturated alkyl chain. The gemini surfactants with a linker of a linear saturated aliphatic hydrocarbon chain exhibited a relatively low CMC value(≤ 0.2 mmol L
A rare case of acrocephaly: Saethre-Chotzen syndrome or Crouzon?
Authors: Molpeceres Rebeca Garrote , Rodriguez Elena Urbaneja , García Hemenegildo González , Pino Vázquez María Asunción , Hernanz Sanz José Luis , Álvarez Guisasola Francisco Javier
Published: April 2016

Acrocephaly is a common neonatal craniofacial malformation. Saethre-Chotzen syndrome (SCS) is one of the acrocephaly related syndromes less frequently described in the literature. A female newborn term was admitted to our Neonatal Unit to study craniofacial dysmorphia without family history of interest. Pregnancy, childbirth and the neonatal period were uneventful. She had exotropia, short anterior-posterior cranial diameter, flat occiput and wide normotensive anterior fontanelle (beginning at the nose root, continuing through the sagittal suture with the posterior fontanelle) without syndactyly. The scanner imaging confirmed an acrocephaly with fusion of bilateral coronal sutures. We initially suspected a cranyosinostosis due to a Crouzon syndrome or SCS. After differential diagnosis and genetic study the patient was diagnosed as having SCS due to a de novo TWIST1 gene mutation. The craniofacial dysmorphias were corrected early by neurosurgical with good results. This case shows a new example of the phenotypic and genotypic variability of these TWIST1 gene mutations.
A note on multiplicative (generalized) derivations with annihilator conditions
Authors: Dhara Basudeb , Pradhan Krishna Gopal
Published: April 2016

Let R be a prime ring with center Z(R), a ∈ R (a ≠ 0) and I
a nonzero ideal of R.
Suppose that

F
,
d
:
R
→
R

${F,d\colon R\rightarrow R}$

are any two mappings such that

F
(
x
y
)
=
F
(
x
)
y
+
x
d
(
y
)

${F(xy) = F(x)y+xd(y)}$

for all

x
,
y
∈
R

${x, y
\in R}$

. For all

x
,
y
∈
I

${x,y\in I}$

, we investigate the identities

a
(
F
(
x
y
)
±
x
y
)
=
0

${a(F(xy)\pm xy)=0}$

,

a
(
F
(
x
y
)
±
y
x
)
=
0

${a(F(xy)\pm yx)=0}$

,

a
(
F
(
x
)
F
(
y
)
±
x
y
)
=
0

${a(F(x)F(y)\pm xy)=0}$

,

a
(
F
(
x
)
F
(
y
)
±
y
x
)
=
0

${a(F(x)F(y)\pm yx)=0}$

,

a
(
d
(
x
)
F
(
y
)
±
x
y
)
∈
Z
(
R
)

${a(d(x)F(y)\pm xy)\in Z(R)}$

,

a
(
d
(
x
)
F
(
y
)
±
y
x
)
∈
Z
(
R
)

${a(d(x)F(y)\pm yx)\in Z(R)}$

and

a
(
F
(
x
y
)
±
F
(
x
)
F
(
y
)
)
=
0

${a(F(xy)\pm F(x)F(y))=0}$

.
Serotonin in Trichinella pseudospiralis: An immunocytochemical study
Authors: Terenina N. B. , Mochalova N. B. , Odoevskaya I. M. , Kreshchenko N. D. , Gustafsson M. K. S. , Fagerholm H-P.
Published: April 2016

This is the first report on the presence and localization of the neurotransmitter serotonin (5-HT) in the nervous system of the nematode Trichinella pseudospiralis, the causative agent of trichinellosis. The orientation of the 5-HT-immunoreactive (5-HT-IR) nerve cells in the adult worm is described. In the anterior region of the worm 5-HT-IR occurs in 7 neurons. Longitudinal nerve cords extend posteriorly from the anterior end. They are connected by transverse commissures. The vulval area is intensively supplied with 5-HT-IR nerve cells and fibres forming a plexus. Two rows of small 5HT-IR structures, hypodermal glands, are visible along the whole nematode body. Because of the conserved structural features among nematodes the 5-HT-IR neurons observed are likely to have counterparts in the model worm, Caenorhabditis elegans. Some basic differences are evident and demand further study.
Description and developmental biology of the predatory diplogastridAcrostichus nudicapitatus(Steiner, 1914) Massey, 1962 (Nematoda: Rhabditida)
Authors: Ahlawat S. , Tahseen Q.
Published: April 2016

Acrostichus nudicapitatus(Steiner, 1914) Massey, 1962 is redescribed and illustrated along with observations on its developmental biology. Most morphometrics of the present population agree well with those ofA. nudicapitatus(Steiner, 1914) Massey, 1962. The largely oviparous females ofA. nudicapitatuslay eggs in single-celled or two-celled stage, 1.5 – 2 h after fertilization. In cultured females, the uterine tract was observed to accommodate occasionally as many as 4 – 6 eggs. The eggs are smooth-shelled, oval in shape measuring 45 – 48 x 23 – 26 μm in dimension. The pole of entry of sperm marks the posterior end of the developing embryo. The embryonation time has been recorded to be 20 – 25 h at 25 ± 2 °C. The first moult occurs inside the egg and the juvenile hatches as second stage juvenile. The gonad development follows the trends found in most rhabditids, however, three prime cells of the 12 vulval precursor cells have been observed to be involved in vulva formation.
Some epidemiological and serological studies on schistosomiasis in Najran area, Saudi Arabia
Authors: El-Shahawy I. S. , Khalil M. I. , Adail A. S.
Published: April 2016

Schistosomiasis is a major cause of morbidity and mortality and has been estimated to infect over 200 million people. Diagnosis of schistosomiasis by detection of specific antibodies is likely to be more sensitive than the traditional method of diagnosis by detection of eggs in stool or urine. Therefore the present study was the first attempt to highlight the seroepidemiology of schistosomiasis among the general population of Najran City, southern of Saudi Arabia, as well as to achieve the performance of the diagnostic tests used. A total of 180 participants attending King Khaled hospital in Najran Province, Saudi Arabia, over a one year period, from September 2013 to September 2014 were screened for the presence of Schistosoma antibody in their blood serum using an indirect hemagglutination assay (IHA). Specific immunoglobulin (Ig) G antibody was evaluated using an enzyme-linked immunosorbent assay (ELISA). Out of the 180 samples of sera tested using IHA, 32 (20 %) were found to be positive with a titer ranging from 1:160 to 1:1280, while 42(23.2 %) revealed Schistosoma IgG. A positive relationship was found between the seroprevalence of schistosomiasis and age of tested participants, especially in the age group of 20-40 years old. Additionally, prevalence of infection was more in males (36 %) than females (7.5 %), and showed statistical significance (P < 0.001). Similarly, there was significant association between the presence of Schistosoma antibodies and the nationality of residence, and education of participants (P < 0.05). The current investigation reveals an alarmingly high prevalence of schistosomiasis among participants in Najran, southern region of Saudi Arabia and this supports an urgent need to re-evaluate the current control measures and implement an integrated, targeted and effective schistosomiasis control measures.
Assessing the usefulness of mineral licks containing herbal extracts with anti-parasitic properties for the control of gastrointestinal helminths in grazing sheep – a field trial
Authors: Nosal P. , Murawski M. , Bartlewski P. M. , Kowal J. , Skalska M. , Zięba D. A
Published: April 2016

One of the alternative methods of parasite control, of particular importance in sustainable farming, is the use of medicinal plants. The specific aim of the present field trial was to assess the anti-parasitic effects of herbal extracts contained in a commercially available lick formulation for sheep. At the outset of this study conducted during the grazing season, all animals were de-wormed and then randomly assigned to one of the two separately kept groups (treatment and control), each consisting of 25 animals (11 ewes and 14 lambs). The treatment group received mineral licks containing the extracts of the plants with anti-parasitic properties, while control animals received standard mineral licks ad libitum. Rectal fecal samples were collected monthly from all animals for the McMaster analyses. There were no significant differences in the prevalence and intensity of helminth infections between the treatment and control groups. Thus, we were not able to ascertain the efficacy of the commercial herbal de-wormer tested for the control of gastrointestinal helminths in grazing ewes and their lambs.
Parasitological examination of northern elephant seal (Mirounga angustirostris) pups for presence of hookworms (Uncinariaspp.) on San Miguel Island, California
Authors: Lyons E. T. , Kuzmina T. A. , Spraker T. R. , Delong R. L.
Published: April 2016

Necropsy and extensive parasitological examination of dead northern elephant seal (NES) pups was done on San Miguel Island, California, in February, 2015. The main interest in the current study was to determine if hookworms were present in NESs on San Miguel Island where two hookworm species of the genusUncinariaare known to be present -Uncinaria lyonsiin California sea lions andUncinaria lucasiin northern fur seals. Hookworms were not detected in any of the NESs examined: stomachs or intestines of 16 pups, blubber of 13 pups and blubber of one bull. The results obtained in the present study of NESs on San Miguel Island plus similar finding on Año Nuevo State Reserve and The Marine Mammal Center provide strong indication that NES are not appropriate hosts forUncinariaspp. Hookworm free-living third stage larvae, developed from eggs of California sea lions and northern fur seals, were recovered from sand. It seems that at this time, further search for hookworms in NESs would be nonproductive.
A helminthological research on three Lacertid lizards species:Acanthodactylus harranensisBaranetal, 2005,Acanthodactylus schreiberiBoulenger, 1878, andMesalina brevirostrisBlanford, 1874, collected from South and South-eastern regions of Turkey
Authors: Düşen S. , Kumlutaş Y , Ilgaz Ç , Avci A , Yakagül C
Published: April 2016

A total of 45 lizards(Acanthodactylus harranensis[n = 15],Acanthodacthylus schreiberi[n = 9] andMesalina brevirostris[n = 21]) were collected from South and Southeastern Regions of Turkey and examined for helminth fauna.Acanthodactylus harranensisharbored 1 species of Nematoda(Skrjabinodonsp.), 1 species of Cestoda(Oochoristica tuberculata)and 1 species of Acanthocephala(Centrorhynchussp. [cystacanth]).Acanthodactylus schreiberiharbored unidentified cysticercoids.Mesalina brevirostrisharbored 1 species of Nematoda(Spauligodon saxicolae). All lizards represents new host records for the helminths reported in this study.
Helminth fauna of Chelonia mydas (Linnaeus, 1758) in the south of Espírito Santo State in Brasil
Authors: Binoti E. , Gomes M. C. , De Calais Junior A. , Werneck M. R. , Martins I. V. F. , Boeloni J. N.
Published: April 2016

Due to an inadequate knowledge about threats to the sea turtle, we aimed to evaluate the helminth fauna of Chelonia mydas which had died on the southern coast of Espirito Santo, Brasil and described the associated tissue pathological lesions. Retrospective and prospective studies on turtle parasites were conducted and tissues samples were collected. 106 of 212 of sea turtles (50 %) were parasitized, and 47 of 106 of infected animals 43.0 % (47/106) were in poor health condition. Seven trematoda families covering 19 different helminths species were identified. Turtles were inhabited with one or more species of parasites, and there was no significant association between parasitism and weakness of the animals. Trematode eggs, with or without giant cells in tissues of various organs were observed.
Molecular and ultrastructure characterization of two nematodes(Thelandros scleratus and Physalopteroides dactyluris)based on ribosomal and mitochondrial DNA sequences
Authors: Goswami U , Chaudhary A , Verma C , Singh H.S.
Published: April 2016

The phylogenetic relationships of the nematode speciesThelandros scleratus(Oxyurida: Pharyn-godonidae) andPhysalopteroides dactyluris(Spirurida: Physalopteridae) were analyzed using the ribosomal 18S rRNAand the mitochondrial cytochrome C oxidase subunit genes. The nematodes were recovered from Brook's house gecko,Hemidactylus brooki(Reptilia: Gekkonidae) from Hast-inapur, Meerut (U.P.), India. The results demonstrated thatT. scleratusshows 100% similarity with another sequence available from the same species and a close relationship (98-99%) with species ofParapharyngodonin both 18S rRNAand cox 1 regions. Regarding the nematodePhysalopteroides. analysis showed a close phylogenetic relationship betweenP. dactylurisand several species ofPhy-saloptera. This is the first sequence of 18S available for any species of the genusPhysalopteroides
Differences in solubility parameters and susceptibility to salting-out between softwood and hardwood lignosulfonates
Authors: Myrvold Bernt O.
Published: April 2016

The salting-out of lignosulfonates (LSs) follows the Hofmeister series, but different LSs show different susceptibility to salting-out. By comparing results for a large number of LSs from different plant species, pulping conditions, and post-treatment of the LS, it was found that the salting-out concentration for different LSs is mainly due to differences in the plant species with guaiacyl LS being much more salt-tolerant than guaiacyl-syringyl LS. The pulping conditions have only a minor effect on the salt tolerance of the different LSs. Post-treatment that increases the molecular weight or reduces the sulfonation also reduces the salt tolerance.
Semitransparent, durable superhydrophobic polydimethylsiloxane/SiO2 nanocomposite coatings on varnished wood
Authors: Tu Kunkun , Kong Lizhuo , Wang Xiaoqing , Liu Junliang
Published: April 2016

A superhydrophobic surface on wood can prevent water adhesion and absorption. However, the practical applications of such a non-wetting surface are hindered by the fragility of the microscopic roughness features that are essential for superhydrophobicity. In this study, semitransparent, mechanically durable superhydrophobic coating was successfully deposited on varnished wood via a simple dip-coating method based on polydimethysiloxane (PDMS)/silica (SiO2) nanocomposites. The surface microstructure and roughness of the hybrid coatings on wood are governed by the mass ratio of SiO2 to PDMS. When the nano-SiO2 particle content reaches a critical level, dual-scale features with micro-scale roughness superimposed with a nanostructure can be formed in the surface coatings, resulting in excellent water-repellency with a contact angle above 150° and a sliding angle below 10°. The coated wood surface maintained essentially the original colour and aesthetic appearance despite slightly declined optical transparency of the hybrid coating caused by aggregation of silica nanoparticles. Sandpaper abrasion tests revealed that the superhydrophobic PDMS/SiO2 hybrid coating on wood retained its microstructure and superhydrophobicity after being repeatedly abraded.
Hydrotreatment of Light Cycle Oil Over a Dispersed MoS2 Catalyst
Authors: Zhang Haiping , Lin Hongfei , Zheng Ying
Published: April 2016

Examination of the hydrotreatment of light cycle oil over a dispersed MoS2 catalyst was conducted in a batch reactor at 375 °C and 1,500 psi. Hydrodesulfurization, hydrodenitrogenation, hydrogenation of aromatics, and hydrocracking activity were all analyzed. Diaromatics are more reactive than monoaromatics. Different sulfur compounds have experimental rates of elimination following the trend of BT>1MBT>> 2MBT>3MBT>4MBT>>DBT≈1MDBT≈2MDBT≈3MDBT. BT and its derivatives are very reactive and easy to eliminate, but become harder to convert as they gain methyl groups. DBTs are harder to eliminate than BTs, and don’t experience significant changes in reactivity as they gain methyl groups. This difference indicates that steric hindrance is more significant in supported catalysts than in unsupported catalysts. Different nitrogen compounds have experimental rates of elimination following the trend of Anilines> Indoles> Carbazoles.
One-Dimensional Model Incorporated with Mechanical Loss and Auxiliary Power for Evaluating Thermodynamic Performance of Stirling Engine
Authors: Li Daijin , Luo Kai
Published: April 2016

Stirling engines are regarded as an efficient and promising power system for underwater devices. Currently, many models have been used to evaluate thermodynamic performance of Stirling engine, but in which mechanical loss and auxiliary power still cannot be modeled with proper mathematical models. A four-cylinder double-acting Stirling engine for Unmanned Underwater Vehicle (UUV) is discussed in this paper. Referring to the Stirling engine experimental results from National Aeronautics and Space Administration (NASA), a one-dimensional model incorporated with empirical equations of mechanical loss and auxiliary power obtained from experiments is presented. The P-40 Stirling engine with sufficient testing results from NASA is utilized to validate the accuracy of the modified one-dimensional model. And the comparison results suggest good agreement between testing and simulation results. The output power maximum error of theoretical analysis results is less than 18 % over testing results, and the maximum error of input power is no more than 9 %. In short, the one-dimensional model is adequate to evaluate the thermodynamic performance of the Stirling engine.
Direktinvestitionen, Exportströme und Beschäftigungseffekte. Gepoolte Regressionen mit Daten aus der amtlichen Statistik für die Schweiz 1985-1997 unter Berücksichtigung branchenspezifischer Besonderheiten / Foreign Direct Investment, Exports and Employment Effects. Pooled Regressions using Official Data for Switzerland 1985-1997 with Emphasis on Sectoral Differences
Authors: Henneberger Fred , Ziegler Alexandre
Published: April 2016

Eine Sonderauswertung der Schweizerischen Nationalbank zu den Direktinvestitionen schweizerischer Unternehmen desaggregiert nach Zielländern und Branchen erlaubt erstmals für den langen Zeitraum von 1985 bis 1997 sowohl für die Gesamtwirtschaft als auch für die zentralen Branchen der schweizerischen Industrie eine Analyse der Auswirkungen der Direktinvestitionstätigkeit auf die Güter- und damit Arbeitsnachfrage in der Schweiz.

Für den gesamten Industriesektor weisen die Ergebnisse der gepoolten Regressionen für die Gruppe der 21 Industrieländer auf eine schwache Substitutionsbeziehung zwischen der Entwicklung der Direktinvestitionen und derjenigen der Exporte hin, nicht jedoch für die Gruppe der 35 Entwicklungsländer. Nach Branchen desaggregiert zeigt sich aber ein weitaus differenzierteres Bild.
Blood, Sweat, and Tears: The Rise and Decline of the East German Economy, 1949–1988 / Blut, Schweiß, Tränen: Aufstieg und Niedergang der ostdeutschen Wirtschaft, 1949–1988
Authors: Blum Ulrich , Dudley Leonard
Published: April 2016

The rise of the East-German economy in the 1950s and 1960s and its decline in the 1970s and 1980s is difficult to explain by neoclassical economics. However; the observed life cycle may be explained by the inclusion of concepts from old and new institutional economics and from functional economics. Three distinct periods may be identified. During the “blood” period of forced development and autocratic rule, the information system and the system of property rights were roughly compatible with the economic structure. Then, in the “sweat” period, an attempt to overtake the capitalistic societies failed. Finally, in the “tears” period, economic decline could only be disguised by unsustainable inflows of foreign capital. This institutional explanation of the East-German collapse is tested with data for the period 1949-1988 and cannot be rejected.
Deskriptive und induktive Eigenschaften zweier Streuungsmaße für nominale Merkmale / Descriptive and Inferential Properties of Two Measures of Dispersion for Nominal Variables
Authors: Vogel Friedrich , Kiesl Hans
Published: April 2016

In dieser Arbeit werden zunächst die deskriptiven Eigenschaften zweier Streuungsmaße für nominale Merkmale, der Entropie und eines neueren Positionsmaßes, erörtert und die Art der Streuungsmessung anhand graphischer Darstellungen verglichen. Darauf aufbauend wird gezeigt, daß - für beide Maße - Schätzfunktionen konstruiert werden können und daß diese Schätzfunktionen asymptotisch erwartungstreu und asymptotisch normalverteilt sind. Diese Eigenschaften liefern die Grundlage für die Konstruktion von approximativen Test- und Schätzverfahren.
Veränderungsraten und ihre statistische Messung. Reminiszenzen und erneuerte Betrachtung / Statistical Measurement of Growth Rates. Reminiscence and the Problem Revisited
Authors: Wiegert Rolf
Published: April 2016

In den Jahrbüchern für Nationalökonomie und Statistik ist in den Jahren 1964-66 eine denkwürdige Kontroverse um die zureichende Schätzung mittlerer Wachstumsraten ausgetragen worden. Eine Klärung der damit verbundenen Probleme wurde durch die schriftlichen Verlautbarungen nicht bewirkt, weil nur inferentielle und pragmatisch-deskriptive Überzeugungen konträr gegeneinander geführt wurden, ohne die eigentliche Frage der Adäquatheit des jeweiligen Vorgehens zu untersuchen und sachlich zu begründen. Diese Diskussion war ein Anlaß, erneut die bleibend aktuellen Fragen der Adäquation von Zielen und Methoden zu diskutieren. In der angewandten Wirtschaftsforschung sind sie unverändert bedeutsam und nicht zu vernachlässigen. Die vorliegende Arbeit untersucht die inhärenten Sach- und Formalprobleme bei der Berechnung/ Schätzung mittlerer Veränderungsraten und bemüht sich um Transparenz. Zugleich befaßt sich der Beitrag mit der stets aktuellen Hintergrundfrage nach der Angemessenheit der Modelle und stellt abschließend einen neuartigen Lösungsansatz für die Schätzung vor, den man sowohl deskriptiv wie auch inferentiell je nach Charakter der verfügbaren Daten verstehen und interpretieren kann.
Is There a Size Gap in Corporate Leverage?. A European Comparison / Gibt es eine Kluft im Leverage europäischer Unternehmen?. Ein europäischer Vergleich
Authors: Coeurderoy Régis
Published: April 2016

The main purpose of this paper is to evaluate corporate debt ratios by size classes in Continental Europe. Evidence is given on a sample of firms in manufacturing industry for ten European countries, all of them being in Euroland apart from Denmark (Austria, Belgium, Denmark, Finland, France, Germany, Italy, Netherlands, Portugal and Spain). The descriptive analysis shows a 15 % point size gap in corporate leverage between small and large companies on average. Even after adjusting for structural factors, the size gap remains at 10 %. Yet, an overall assessment should not lead us to overlook national features when comparing small and large companies. In particular, three main groups emerge: in Germanic countries (Austria and Germany), the gap is the largest, mainly because of regulatory specificities. In a second cluster, companies from Denmark, France and Portugal exhibit significant differences in averages across sizes but at a lower extent than in the first group. As regards the other countries, even though the size gap is still the dominant pattern, the situation is less definite and deserves case by case analysis.
Ost-West-Migrationspotenzial: Wie groß ist es? / East-West-Migration Potential: How many will go West?
Authors: Straubhaar Thomas
Published: April 2016

Wie viele Menschen aus den mittel- und osteuropäischen Ländern (MOEL) werden von dem mit dem EU-Beitritt verbundenen Recht auf Freizügigkeit Gebrauch machen und nach Westen in die „alten" EU-Länder wandern? Die vorgestellten Simulationen ergeben eine Bandbreite für das Ost-West-Migrationspotenzial in der Größenordnung von brutto jährlich 0,2 % bis 0,4 % der mittel- und osteuropäischen Bevölkerung, die bei einer Nettobetrachtung (unter Einbezug der Rückwanderungen) auf rund 0,1 % der Bevölkerung schmilzt. Hochgerechnet auf eine erste EU-Erweiterungswelle, ergibt sich für die MOEL-8 (Slowenien, Tschechien, Ungarn, Slowakei, Polen, Estland, Litauen, Lettland) ein Ost-West-Migrationspotenzial, das in 15 Jahren brutto etwa 3 % - 4 % und netto etwa die Hälfte, nämlich 1½ % - 2 % der Bevölkerung der MOEL- 8 erreicht. Dies sind rund 3 Millionen Menschen (brutto) bzw. 1 - 1½ Millionen Menschen (netto). Anders herum gesehen, entsprechen diese drei Millionen Menschen gerade einmal 0,8 % der EU-Bevölkerung. Mit Blick auf die zu erwartende Schrumpfung der Bevölkerung in den heutigen EU-15 Ländern und dem damit einhergehenden Alterungsprozess dürften diese Zuwanderungsbewegungen kaum negativ ins Gewicht fallen. Von einer „Völkerwanderung" kann also keine Rede sein!
Die EU-Beschäftigungslücken im Spiegei von Erwerbstätigenquoten / The EU Employment Gaps in the Mirror of Employment- Population Ratios
Authors: Klös Hans-Peter , Schnabel Claus
Published: April 2016

Eine Analyse europäischer Beschäftigungsdefizite, die Erwerbstätigenquoten statt der traditionellen Erwerbsquoten verwendet, macht deutlich, dass in vielen EU-Ländern noch unausgeschöpfte Beschäftigungspotenziale bestehen, insbesondere bei älteren Arbeitnehmern, aber auch bei Frauen und im Dienstleistungssektor. Könnte die EU-15 die gleiche Erwerbstätigenquote wie die USA erreichen, so fänden fast 34 Millionen Personen zusätzlich Beschäftigung. Selbst das neue EU-Ziel einer Erwerbstätigenquote von 70 % würde die Schaffung von 23 Millionen Arbeitsplätzen bedeuten und erscheint deshalb überaus ehrgeizig. Zwar haben einige EU-Mitgliedsländer dieses Ziel bereits verwirklicht, doch streuen die Erwerbstätigenquoten so stark zwischen den einzelnen EU-Ländern, dass eine für alle Mitgliedstaaten einheitliche Beschäftigungspolitik wenig zielführend und ratsam erscheint.
Leading Indicators of German Business Cycles. An Assessment of Properties / Frühindikatoren der deutschen Konjunktur. Eine Beurteilung ihrer Eigenschaften
Authors: Fritsche Ulrich , Stephan Sabine
Published: April 2016

A reliable leading indicator should possess the following properties: (1) The movements in the indicator series should resemble those in the business cycle reference series. (2) The relation between the reference series and the indicator should be statistically significant and stable over time. (3) The inclusion of the indicator in out-of-sample forecasting procedures should improve the predictive power. Our analysis deals with tests for these requirements applied to German data. We used frequency domain analysis, different Granger-causality tests and out-of sample forecasts. Only few indicators passed all tests. Their inclusion into VAR-based forecasts improves the forecast in the very short run. Further research should concentrate on the unsolved problem of the prediction of business cycle turning points.
Small is Beautiful?. Entwicklungslinien im Makroökonometrischen Modellbau / Small is Beautiful?. Tendencies in Macroeconometric Modelling
Authors: Heilemann Ullrich
Published: April 2016

Die Arbeit beschreibt Tendenzen im makroökonometrischen Modellbau der OECD-Länder im Zeitraum 1930 bis 1990. Sie zeigt, dass die Modelle im Umfang beträchtlich zunahmen, vor allem die Definitionsgleichungen und die Anzahl der exogenen Variablen. Ursächlich dafür waren sowohl angebotsseitige wie nachfrageseitige Faktoren - insbesondere die verbesserten technischen Möglichkeiten, aber auch die wachsenden Informationsbedürfnisse der Nutzer. Besondere Aufmerksamkeit widmete man den oft zitierten Alternativen „small and beautiful“ und „big and ugly“. Dabei zeigte sich, dass die so mit der Modellgröße assoziierten Eigenschaften nicht gegeben sind -,Größe ' ist nicht Ziel, sondern Ergebnis der Modellierung. Große Modelle erscheinen oft als komplex, und obwohl das im Grunde ein subjektives Urteil ist, sollten die Modellbauer sich mehr als bisher darum bemühen, die Transparenz ihrer Modelle zu erhöhen. Die Tendenz zu größeren Modellen dürfte sich zwar abschwächen, aber nicht zum Stillstand kommen.
Sleeping Process Patents and Environmental Innovation / Umweltpolitik und schlafende Patente
Authors: Hübner Marion
Published: April 2016

Using a duopoly model of a patent race, it is shown that a stricter environmental policy might increase the probability of a sleeping patent instead of encouraging environmental technological progress. Two scenarios are discussed. The first concerns the regulation of a firm that competes with a foreign firm. The second concerns the regulation of a duopoly in a closed economy.
Multiple Attribute Group Decision-Making Methods Under Hesitant Fuzzy Linguistic Environment
Authors: Liu Xiaodi , Zhu Jianjun , Zhang Shitao , Liu Guodong
Published: April 2016

The aim of this paper is to develop some aggregation operators for multiple-attribute group decision making (MAGDM) with hesitant fuzzy linguistic information. First, the relationship between uncertain linguistic variable and hesitant fuzzy linguistic term set (HFLTS) is discussed. Some operations and aggregation operators for HFLTSs are developed. Second, based on the hesitant fuzzy linguistic weighted arithmetic averaging operator and the hesitant fuzzy linguistic hybrid averaging operator, an approach to MAGDM problem with hesitant fuzzy linguistic information is proposed. Finally, a practical application of the developed approach to supplier selection in a supply chain and a comparative analysis with other methods are presented.
The Persian squirrel of Kurdistan Province, western Iran: what determines its geographic distribution?
Authors: Sadeghi Maedeh , Malekian Mansoureh
Published: April 2016

Here, we used the maximum entropy (MAXENT) method to predict habitat distribution of the Persian squirrel in oak forests of Kurdistan Province, western Iran. We used 70 points with known occurrence of the species and 17 environmental variables (climatic variables represented annual trends in temperature and precipitation, seasonality and extreme or limiting environmental factors) to map the species distribution. The MAXENT model showed high performance. Using a 0.5 logistic probability threshold, the models suggested about 16,783.5 ha of the study area to have high suitability for the Persian squirrel. These areas were thus estimated as “good” habitats. Amongst the environmental variables, land cover had the greatest role in the Persian squirrel’s distribution. Precipitation and temperature were the two major climatic factors that affected the Persian squirrel’s distribution. Gap analysis showed that many parts of the species habitat have remained unprotected what can threaten the survival of the studied species in the region. These findings can be used to develop conservation management plans and boost the network of protected areas in the region.
The impact of medium frequency pulsed magnetron discharge power on the single probe Langmuir measurements and resulted plasma parameters
Authors: Wiatrowski A , Posadowski W.M
Published: April 2016

The resonant type power supplies of medium frequency designed for magnetron sputtering processes often use pulse density modulation to regulate the average discharge power level. While the output power level changes then number of pulses in a group changes, but the discharge current pulses are the same from pulse to pulse: their parameters (duration time, amplitude) do not change with the discharge power. The goal of this paper is to present the influence of medium frequency discharge power level on the direct current I-V characteristics of a single Langmuir probe and resulting plasma parameters caused by the pulse density modulation. The sputtering processes of titanium and copper were diagnosed at two spatial positions. The measured Langmuir probe I-V characteristics showed strong dependence on the discharge power. As the discharge powering pulses stay the same with the discharge power level change, such influence was unlikely to occur. Using time-resolved analysis of probe current waveforms the origin of this influence was indicated. The influence of discharge power level on the single probe Langmuir I-V characteristics and resulting plasma parameters was eliminated using a simple method of scaling the results. Finally, the reliable plasma parameters were calculated.
Sea Level Rise and Land Subsidence Contributions to the Signals from the Tide Gauges of China
Authors: Parker Albert
Published: April 2016

The tide gauges measure the local oscillations of the sea level vs. the tide gauge instrument. The tide gauge instrument is generally subjected to the general subsidence or uplift of the nearby inland, plus some additional subsidence for land compaction and other localised phenomena. The paper proposes a non-linear model of the relative sea level oscillations including a long term trend for the absolute sea level rise, another term for the subsidence of the instrument, and finally a sinusoidal approximation for the cyclic oscillations of periodicities up to decades. This non-linear model is applied to the tide gauges of China. The paper shows that the limited information available for China does not permit to infer any proper trend for the relative rates of rise, as the tide gauge records are all short or incomplete and the vertical movement of the tide gauge instruments is unassessed. The only tide gauge record of sufficient length that may be assembled for China is obtained by combining the North Point and Quarry Bay tide gauges in Hong Kong (NPQB). This NQPB composite tide gauge record is shown to have similarities with the tide gauge records of Sydney, equally in the West pacific, and San Diego, in the east Pacific, oscillating about the longer term trend mostly determined by the local subsidence. As it is very well known that China generally suffers of land subsidence, and the tide gauge installations may suffer of additional subsidence vs. the inland, it may be concluded from the analysis of the other worldwide tide gauges that the sea levels of China are very likely rising about the same amount of the subsidence of the tide gauges, with the sea level acceleration component still negligible.