bluuebunny/crossref_metadata_2025 huggingface dataset:
A new denoising approach based on mode decomposition applied to the stock market time series: 2LE-CEEMDAN
Authors: Akşehir Zinnet Duygu , Kılıç Erdal
Published: February 2024

Time series, including noise, non-linearity, and non-stationary properties, are frequently used in prediction problems. Due to these inherent characteristics of time series data, forecasting based on this data type is a highly challenging problem. In many studies within the literature, high-frequency components are commonly excluded from time series data. However, these high-frequency components can contain valuable information, and their removal may adversely impact the prediction performance of models. In this study, a novel method called Two-Level Entropy Ratio-Based Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (2LE-CEEMDAN) is proposed for the first time to effectively denoise time series data. Financial time series with high noise levels are utilized to validate the effectiveness of the proposed method. The 2LE-CEEMDAN-LSTM-SVR model is introduced to predict the next day’s closing value of stock market indices within the scope of financial time series. This model comprises two main components: denoising and forecasting. In the denoising section, the proposed 2LE-CEEMDAN method eliminates noise in financial time series, resulting in denoised intrinsic mode functions (IMFs). In the forecasting part, the next-day value of the indices is estimated by training on the denoised IMFs obtained. Two different artificial intelligence methods, Long Short-Term Memory (LSTM) and Support Vector Regression (SVR), are utilized during the training process. The IMF, characterized by more linear characteristics than the denoised IMFs, is trained using the SVR, while the others are trained using the LSTM method. The final prediction result of the 2LE-CEEMDAN-LSTM-SVR model is obtained by integrating the prediction results of each IMF. Experimental results demonstrate that the proposed 2LE-CEEMDAN denoising method positively influences the model’s prediction performance, and the 2LE-CEEMDAN-LSTM-SVR model outperforms other prediction models in the existing literature.
Implementation of the digital functional settlement at a federal public university: problems and proposed solutions
Authors: Da Silva Beatriz Bahia Gomes , Gomes Carlos Francisco Simões , Ferraz Fernando Toledo , Dos Santos Marcos , Do Carmo Annibal José Roris Rodriguez Scavarda
Published: February 2024

The aim of this article is to present a proposal for improving the implementation of the Digital Functional Record in a federal public university.In pursuit of this objective, the article seeks to outline the implementation phases, the structure it will take, the professionals involved, the regulations governing the digital functional record, and the challenges faced, while also suggesting some solutions. The applied methodology is qualitative and descriptive, relying on bibliographic and documentary analysis. It is concluded that the study introduces the digital functional record in a federal public university, detailing its stages, the challenges encountered, and proposing improvements. If these proposed improvements were put into practice and became ingrained in the institution's culture, it is believed that they would bring greater benefits, preventing numerous challenges during implementation.
Andarilhos de estrada e os entraves no acesso à seguridade social
Authors: Scremin Elton José , De Freitas Junior Miguel Archanjo , Picinin Cláudia Tania
Published: February 2024

O mínimo existencial, calcado no princípio da dignidade da pessoa humana, tem como sustentáculo os direitos sociais componentes do artigo 6º da Carta Magna, mas sua positivação não é garantidora de sua implementação. A população citadina percebe com alguns óbices esses direitos, mas quem vive na rodovia, como Andarilhos de Estrada e Trecheiros, não os vislumbram. O objetivo deste artigo é identificar se os direitos sociais, especialmente a Seguridade Social, são acessados pelos nômades e errantes das rodovias federais. Pretende-se verificar se a Proteção Social, assegurada no plano jurídico formal, possui alguma efetividade para essa população. Concluiu-se que vários são os óbices na implementação dos direitos sociais para Andarilhos de Estrada e Trecheiros. A Seguridade Social está precariamente acessível somente no direito à saúde, restringindo-se às situações emergenciais; a previdência social esbarra no caráter contributivo enquanto os princípios da matricialidade sociofamiliar, da descentralização político administrativa e da territorialidade impedem o atendimento na área da assistência social.
Quality of Reliability of information on H3N2 Influenza in Youtube: A Cross-sectiinal Study
Authors: Singh Gurinderjeet , Devadiga Harshita Chandrashekhar , Prakash Rashmi , Sundaram Dakshin Meenashi , Sasimohan Jahnavi Thokala , Pannu Sagal
Published: February 2024

Introduction: Influenza is a highly communicable viral respiratory illness known to cause outbreaks, such as the current H3N2 outbreak in India. YouTube is one of the most popular sources to obtain information regarding symptoms, treatments, and prevention of diseases like influenza in the general public. Aim: To assess the quality and reliability of information related to H3N2 influenza using the Global Quality Score (GQS) and reliability score, respectively. Materials and Methods: A cross-sectional study was conducted to evaluate the type of information, quality, and reliability of videos about Influenza H3N2 on YouTube using the GQS and the Reliability Score (DISCERN) scale, respectively. The Kruskal-Wallis test was used to assess differences in quality and reliability depending on the type of uploader. Results: The study found that 85% of videos focused on prevention/vaccination, 83.3% discussed the cause/aetiology of influenza, while only 31.7% covered investigations/tests. News agencies uploaded the most videos (46.7%), followed by doctors (18.3%), with minimal contribution from hospitals (8.3%). News agencies had the highest Video Power Index (VPI) compared to other groups, and there were no significant differences in GQS score across different groups. Conclusion: Verified information from proper resources should be uploaded by responsible healthcare professionals like doctors and health organisations. The videos should have an exceptional reliability score and Global Quality Index. The quality of content should be easy to understand for the general public and should provide additional sources of information, educating the viewer to contact his/her physician concerning the diagnosis and further evaluation of the same.
Animal Health Service Delivery in Ethiopia: A Review
Authors: Ahmed Mustafe Abdi , Hussen Ahmed Hasan , Bashir Bashir Mohamed , Ibrahim Abdilahi Saleban
Published: February 2024

Ethiopian livestock population has reached about 52 million cattle, 33 million Sheep, 30 million goats and 2.5 million camels. The livestock sub-sector contributes an estimated 12% of the total and over 45% to the agricultural gross domestic product (GDP). However, the benefits derived from livestock are far below the existing potential. While many factors are attributable to the problem, livestock diseases remain the most important constraint to the development of the subsector. This is because livestock diseases are distributed across all agroecological zones of the country. In addition, the Ethiopian Government is building two standard quarantine stations in strategic locations closer to the seaports of Djibouti and Berbera. APHRD is also introducing hazard analysis critical control point (HACCP) systems in two model abattoirs, namely, Mojo Modern and Luna. The two export abattoirs are expected to be accredited for HACCP at international levels.
Perceived Barriers to Physical Activity among Overweight and Obese Adult Patients Attending General Out-Patient Clinic in Lagos University Teaching Hospital
Authors: Adeyemi Samuel Sogo, , Adeyemi Ayopo Felicia, , Ogunbanwo Babatunde Michael, , Akinosi Joel Oyekunle,
Published: February 2024

Background: Globally, only 1 in 4 adults engage in the recommended amounts of physical activity for health. The increasing rates of physical inactivity are partly caused by perceived obstacles to physical activity. Physical inactivity is the primary cause of roughly 21-25% of the burden of breast and colon cancer, diabetes, and ischemic heart disease.

Study Aim: To determine the perceived barriers to physical activity among overweight and obese adult patients attending the GOPC, LUTH using the barrier portion of the Exercise Benefit and Barrier Scale (EBBS).

Methodology: The research was a cross-sectional, descriptive study conducted in LUTH. Data was collected by means of questionnaire and interview. Statistical package for social sciences (SPSS IBM) version 25 was used for data entry, cleaning, and assessment. Frequency and percentage were used to represent all categorical parameters, and means, standard deviation, or, in the case of skewed continuous variables, median and interquartile range, were used to summarize them via systematic random sampling, 285 overweight and obese adults between the ages of 18 and 64 were chosen.

Result: The majority of overweight and obese adults (78.6%) felt that there were moderate to high levels of barriers to physical activity, most of which had to do with physical exertion. Age, family type, highest degree of education, type of occupation, median earnings, co-morbidity, smoking, and alcohol consumption, though significantly associated with levels of perceived barriers, were not independent predictors of a high level of perceived barriers.

Recommendation: Further evaluation of the perceived barriers to physical activity should be carried out to identify overweight and obese adults who encounter high barriers to physical activity. During lifestyle counseling, physical exertion, the most common barrier subscale to physical activity in this study, should be considered and addressed as appropriate.
Evaluation of the Most Effective Plant Extracts, Bioagents and Chemical Fungicides In vitro against Powdery Mildew of Pea
Authors: Bhosale A. V. , Karade V. M. , Kumbhar C. T. , Khadtare R. M. , Rajenimbalkar V. M. , Shinde S. S.
Published: February 2024

The present investigation was carried during 2022-23 at Plant Pathology Section, College of Agriculture, Pune-05 with the objectives of evaluation of the most effective plant extracts, bioagents and chemical fungicides in vitro. Effect of six plant extracts, bioagents and chemical fungicides were studied in vitro by hanging drop method where the study revealed that garlic (Allium sativum), followed by neem (Azadiracta indica) showed highest inhibition of spore germination for powdery mildew. After 48 hours of incubation, the spore germination rate ranged from 3.15 % to 34.45 %, where garlic showed the highest inhibition at 95.30 %, followed by neem at 91.03 %. The efficacy of bioagents was evaluated by preparing the bacterial and fungal culture filtrates where Trichoderma harzianum and Pseudomonas fluorescens were found to be the most effective with tune of 56.86% and 50.72% of efficacy respectively against Erysiphe pisi. Among all chemical fungicides, hexaconazole (0.05 %) resulted as the most effective chemical fungicide against powdery mildew of pea. These findings can be useful in developing safer and more eco-friendly methods to control powdery mildew and protect crops.
Levels of Phthalate Acid Esters in Drinking Water Bottled in PET (Polyethylene Terephthalate) and PC (Polycarbonates) Bottles - stored under Different Storage Conditions in Mwanza City, Tanzania
Authors: Mrema, Evarist E.  , Chaula, D. N  , Chove, B.E
Published: February 2024

Bottled drinking water is widely advertised and sold in glass or, to a greater extent, plastic bottles with metallic or plastic caps, and is regularly drank by both children and adults. Mwanza City markets have many brands of bottled drinking water packed in PET and PC plastic bottles whose polymers may contain additives such as phthalates. Certain cancer types, hormone imbalances, and developmental delays have all been connected to these phthalates, which are harmful to human health. This study investigated, the effects of storage conditions, time spent in storage, and type of container polymer on the leaching of phthalates from packaging materials into particular brands of locally produced PC and PET bottled drinking water that are regularly consumed by adults and children and sold in Mwanza City markets. The method of determination was liquid-liquid extraction followed by chromatographic analysis for identification of the specific phthalates compounds.

The results that the lowest mean Di methyl phthalates (DMP) concentration in water packed in PET bottles was 0.085 µg/mL before storage and that the mean DMP concentration increased to 0.235 µg/mL following six months of storage at room temperature and outdoor temperature. Additionally, the 18.9-liter PET bottle migrated higher than the 1.5-liter PET bottle due to its larger surface area for water contact and higher surface-to-volume ratio; however, it was found that production contamination, not migration, was the cause of the higher Di methyl phthalates concentrations in the PC bottles. These findings suggest that storing PET bottles containing drinking water at room and outdoor temperatures for an extended period of time directly impacts phthalate migration. Furthermore, this study shows reusing plastic water bottles raises the risk that the inner surface will deteriorate and release more phthalates, which raises concerns about the safety of drinking water that has been prepared and stored in a plastic bottle.
Temperature Tolerance in the Five Field Strains of Trichogramma chilonis from Northern Districts of Tamil Nadu, India
Authors: Prabhu B. , Edward Y. S. Johnson Thangaraj , Priya R. Vishnu , Ramanathan A. , Jeyaprakash P.
Published: February 2024

The egg parasitoid, Trichogramma chilonis is a potential egg parasitoid in the agricultural ecosystem, reducing many lepidopteran pest incidences. The laboratory strains of T. chilonis was significantly inferior to the ecotypes collected from fields in their parasitisation potential and tolerance to temperature due to continuous exposure to temperature extremes in the field. Hence, a study was undertaken to evaluate the laboratory reared strain of T. chilonis with that of other ecotypes to identify a temperature tolerant ecotype for use in pest management programme. Five ecotypes of T. chilonis were collected from farmer's fields on sugarcane and citrus using sentinel egg technique by exposing egg cards of Corcyra cephalonica, mass reared on C. cephalonica for three successive generations and tested for their relative tolerance to temperature in comparison with the laboratory population. The emergence percentage of the parasitoid varied with the ecotypes tested and all the field collected ecotypes recorded increased emergence compared to the laboratory population. At 150 C, the emergence was significantly higher in Chitteri ecotype (83.44%) followed by Arungunam and Amirthapuram ecotype (78.65 and 75.57%). The performance of all the ecotypes were best at 200 C and Chitteri ecotype performed significantly better compared to other ecotypes and the laboratory population with an adult emergence of 95.66 per cent. It was followed by Arungunam ecotype (88.65%) at 200 C. While the laboratory population and other ecotypes failed to develop at 350 C, Chitteri and Arungunam ecotypes were able to develop with 9.66 and 7.25 per cent adult emergence from the parasitised eggs.
Melatonin and Gynecologic Disorders: A Literature Review
Authors: Ferreira Igor de Oliveira , Barbon Mariângela , Rosa Júlia Tarter da , Costella Ana Paula , Brietzke Aline Patrícia , Laste Gabriela
Published: February 2024

The present study aimed to review the relevant literature for studies describing the treatment of gynecologic disorders with melatonin, and the clinical relevance of melatonin supplementation in the field of gynecology. We searched the following databases for articles published between 2011 and 2022 that investigated the pathophysiology of the relationship between melatonin and gynecological pathologies in humans: PubMed, MEDLINE, and Embase databases. The 10 included studies primarily focused on the effects of melatonin on patients with polycystic ovarian syndrome (PCOS), as a treatment to reduce pain and improve sleep quality in gynecological pathologies, and as a treatment option for endometriosis. The findings of the present literature review suggested that melatonin can be beneficial in the treatment of PCOS, dysmenorrhea, and endometriosis. The effects of melatonin on MR1A and MR1B receptors, which are present  in the epithelial cells of the endometrial gland, in addition to its known analgesic, anti-inflammatory, and antioxidant properties were also addressed. We concluded that there is a vast field of research on melatonin supplementation and its effects on gynecologic disorders. We also verified the prospects of its use as a therapeutic agent in the auxiliary treatment of gynecological diseases.
Post-Traumatic Neurodystrophy
Authors: GLICK E. N. , HELAL B.
Published: August 2005

This paper reports the results with corticosteroid therapy given to patients with neurodystrophy who failed to improve on other treatment, including intensive physiotherapy.
The use of Locally Based Triangular Skin Flaps for the Repair of Finger Tip Injuries
Authors: WESTON P. A. M. , WALLACE W. A.
Published: August 2005

This paper presents the results of a series of thirty-one finger tip injuries treated by local triangular advancement flaps. Criteria for selection of patients for this type of repair and several points of technique are discussed.
Thorn-Induced Granulomata of Bone
Authors: DICKSON R. A. , KEMP F. H.
Published: August 2005

A case of thorn-induced granuloma of bone is presented and discussed in relation to the previous eight cases reported. The condition affects the exposed areas, usually the hands, of children. It may be as long as nine months from the initial episode of injury or inflammation to presentation as pseudo-tumour. The radiographic appearances are those of a chronic granuloma with longitudinal cavitation and adjacent periosteal reaction and as such can be differentiated from Ewing’s sarcoma, osteoid osteoma, tuberculosis dactylitis, benign osteoblastoma, and stress fracture.
Subclavian Artery Aneurysm due to Costoclavicular Compression
Authors: FIDLER M. W. , HELAL B. , BARWEGEN M. G. M. H. , Van DONGEN R. J. A. M.
Published: August 2005

Proximal involvement of the innervation of the arm is a well recognised cause of hand symptoms; a proximal vascular abnormality is rarely responsible. This case report describes such a rare cause, namely, a post-stenotic aneurysm of the subclavian artery due to an abnormal first rib but in the absence of a cervical rib or scalene bands.
Multiple Superficialis Motor for Opponens and Lumbrical Replacement: One Stage Correction of Leprous Claw Hand
Authors: SHAH ATUL
Published: August 2005

A new one stage approach for the correction of total claw hand in leprosy has been described using multiple superficialis motor for opponens and lumbrical replacement. Five cases have been operated with good results by this technique. The operative technique is described, advantages and precautions discussed.
Metacarpophalangeal Joint Arthroplasty Eleven Year Follow-up Study
Authors: FLEMING STEPHEN G. , HAY EDWARD L.
Published: August 2005

During a period from April, 1972 to May, 1983, 339 Swanson silastic implants were implanted in eighty-two hands of fifty-five patients. A follow-up study was performed to evaluate the long-term function of these implants. Our follow-up study indicates that metacarpophalangeal joint arthroplasty can relieve pain, correct deformity, improve appearance and improve hand function by providing functional motion and stability. Few long-term problems were noted and the functional benefits gained by surgery decreased little with time. Patient satisfaction was high.
Recurrent Dorsal Trans-Scaphoid Perilunate Dislocation
Authors: LOWDON I. M. R. , SIMPSON A. H. R. W. , BURGE P.
Published: August 2005

A case is presented in which trans-scaphoid perilunate dislocation occurred through a scaphoid non-union. The place of open reduction and immediate bone grafting is discussed.
Terminal Branch of Anterior Interosseous Nerve as Source of Wrist Pain
Authors: DELLON A. LEE , MACKINNON SUSAN E. , DANESHVAR ALI
Published: August 2005

The terminal branch of the anterior interosseous nerve is described anatomically and demonstrated histologically. Injury to this nerve can be the source of persistent, dull aching volar wrist pain. Suitability for partial volar wrist denervation is determined by functional testing before and after a diagnostic nerve block. Experience with twelve patients with this problem is presented.
Entrapment Neuropathy Caused by Tophaceous Gout
Authors: AKIZUKI S. , MATSUI T.
Published: August 2005

Entrapment neuropathy associated with gout is a rare occurrence. We report two cases of entrapment neuropathy of ulnar tunnel syndrome and carpal tunnel syndrome caused by gouty tophi. Problems related to its mechanism and treatment are discussed.
A Tendon Sheath Tumour Presenting as Trigger Finger
Authors: ONI O. O. A.
Published: August 2005

The symptom of trigger finger may be caused by a variety of lesions. This report describes a trigger finger caused by a tumour in the tendon sheath.

Trigger finger refers to transient arrest of motion in a finger. It may be caused by a variety of lesions such as those of the volar plate (Yancey & Howard, 1962) and joint capsule (Aldred, 1954), structural abnormalities of the metacarpal head (Flatt, 1961), lacerations of the flexor tendons (Janecki, 1976) and ‘loose bodies’ (Milford, 1971). Triggering as a result of tumour of the tendon sheath does not, however, appear to have been reported.
Juvenile Xanthogranuloma of the Hand
Authors: MATSUZAKI A. , YO S. , ISAYAMA T.
Published: August 2005

A case of juvenile xanthogranuloma in the hand is reported. The lesion was atypical clinically, being sited in the hand and the tumour was so large that it extended from the palmar to the dorsal surface. Curettage was performed at seven weeks after birth and histological examination established a diagnosis of juvenile xanthogranuloma. The post-operative course was uneventful, and the residual lesion had disappeared spontaneously four years after operation.
Arterio-Venous Hamartoma of the Hand
Authors: BINNS M. , NOBLE J. , MARCUSON R.
Published: August 2005

Hamartoma in the hand (apart from the glomus tumours) is a rare tumour. A case is presented with unusual features. Aetiology, diagnosis and treatment are discussed.
Acute Calcific Periarthritis in a Child
Authors: MERCER N. S. G. , NEWMAN J. H. , WATT I.
Published: August 2005

We wish to present an account of a child who developed acute calcification in his thenar eminence to highlight the difficulty in differentiation between calcific periarthritis, acute infection, on clinical grounds.

Calcific periarthritis is due to hydroxy apatite crystal deposits in bursae, tendons and ligaments (Bonavita 1980) with characteristic radiographic appearances of opacities of variable density and shape around joints (Hitchcock 1959).

The condition was first described in the shoulder, by Duplay in 1870 (Sandstrom 1938) and this remains the most commonly affected site. The hip, elbow, wrist, knee and ankle may also be involved but involvement of the hand is uncommon. Involvement in this site was first described in 1924 by Cohen (Carrroll 1955). The previously reported age span ranged from thirteen years upwards, with an average of forty-five years, both sexes being equally affected (Currey 1970, Hitchcock 1959, Bonavita 1980).
A Method of Assessment of Pollicisation
Authors: PERCIVAL N. J. , SYKES P. J. , CHANDRAPRAKASAM T.
Published: August 2005

The evaluation and comparison of results of pollicisation for different pre-operative conditions is difficult as no standard method exists. An assessment is proposed, based upon tip pinch, opposition, pulp pinch, grasp, mobility, sensitivity and cosmetic appearance which gives a numerical score.
A Personal Technique for Treatment of Scaphoid Non-Union
Authors: BRUNELLI G. A. , BRUNELLI G. R.
Published: August 2005

We describe a personal technique for the treatment of scaphoid non-union, consisting of styloidectomy of the radius associated with axial perforation of the scaphoid, emptying of the bone, filling it again by cancellous bone taken from the styloid and securing it with a peg obtained from the cortex of the same styloid. 52 patients out of 77 operated on with this technique were reviewed. Results are shown and seem to be better than those found in literature.
Reconstruction of Sheath with Fascial Graft in Flexor Tendon Repair
Authors: AN-MIN LIU , SHI-BI LU
Published: August 2005

Using chicken’s toes as an experimental model, we compared the healing process and function recovery of partially injured flexor tendons when the sheath was repaired with fascial graft, sheath patch or was left as a defect. Post-operatively, the toes were immobilised or mobilized immediately. Histological study and the measurement of tendon sliding revealed that the sheath reconstruction and mobilised groups were better than the sheath defect or immobilised groups. We also found the fascial graft was superior in the reconstruction of tendon sheath and may become synovial-like tissue under the sliding pressure of the tendon.
A Diagnostic Problem in Tuberculous Dactylitis
Authors: JENSEN C. M. , JENSEN C. H. , PAERREGAARD A.
Published: August 2005

We report a case of tuberculous dactylitis. This rare manifestation of extra-pulmonary tuberculosis must be kept in mind in the diagnosis of a slowly-growing bone tumour. The diagnostic problems and pitfalls are discussed.
Tumourous Deposition of Calcium Pyrophosphate Dihydrate Crystals in the Wrist
Authors: OHSHIO I. , OGINO T. , SATOH S. , KONARI M. , NAGASHIMA K.
Published: August 2005

A 63-year-old man had a tumourous deposition of calcium pyrophosphate dihydrate crystals in the palmar aspect of the wrist. Traumatic micro-fracture or osteoarthritis was thought to have triggered the deposition of these crystals. It should be possible to differentiate the lesion clinically and radiologically from tumoural calcinosis, in which the deposits consist of calcium carbonate and/or calcium phosphate.
Brief report: Associations of parental warmth, peer support, and gender with adolescent emotional distress
Authors: Operario Don , Tschann Jeanne , Flores Elena , Bridges Margaret
Published: August 2005

This is an exploratory study of the associations among parental warmth, peer support, gender, and emotional distress in a sample of 308 adolescents in the United States. Parental warmth was associated with less emotional distress, whereas turning to peers for support during family conflict was associated with more emotional distress. Gender moderated these associations in multivariate analyses. Emotional distress was highest among females who reported low levels of parental warmth and who turned to peers for support, in comparison with females who also turned to peers for support but had higher parental warmth. Findings contribute to a growing literature on contextual factors associated with adolescent psychosocial well‐being.
Transient biventricular dysfunction following pericardiocentesis
Authors: Ligero Carmen , Leta Ruben , Bayes‐Genis Antoni
Published: August 2005

We report the case of a 41‐year‐old woman admitted to the hospital due to cardiac tamponade as the first manifestation of a pulmonary neoplasm. The patient developed an early biventricular dysfunction and pulmonary edema after removal of the pericardial effusion, with complete recovery within ten days. Since transient ventricular dysfunction after pericardiocentesis is a very unusual complication, we present a review of the different mechanisms suggested in the literature to explain the pathophysiology of this rare phenomenon.
Nuclear-magnetic-resonance interaction mechanism in Rb2CoCl4 single crystals with the electric magnetic type
Authors: Lim Ae Ran , Hong Kwan Soo
Published: August 2005

The Rb87 spin-lattice relaxation time of Rb2CoCl4 single crystals grown using the slow evaporation method was measured using nuclear magnetic resonance. The recovery trace for the central line of Rb87 with dominant magnetic relaxation cannot be represented with a single exponential function, but can be represented with a linear combination of two exponential functions. The change in the Rb87 spin-lattice relaxation rate near Tc1 corresponds to the ferroelectric to incommensurate phase transition. There is a weak anomalous contribution to T1, and this seems to be the only detectable influence of a structural phase transition. The temperature dependence of T1−1 near Ti is more or less continuous and is not affected by the normal-incommensurate phase transition. For T>Ti, the spin-lattice relaxation rate is governed by molecular motion as described by the Bloembergen-Purcell-Pound theory. This behavior is different to that found for Rb in Rb2ZnCl4. The phase-transition temperatures of the Rb2CoCl4 and Rb2ZnCl4 single crystals are quite similar, but their phase-transition mechanisms are different. The nuclear-magnetic-resonance (NMR) interaction mechanism in Rb2ZnCl4 is well known to be of the electric quadrupolar type whereas in Rb2CoCl4 it is of magnetic origin. Therefore a completely different NMR behavior is obtained in the two crystals.
Composition dependence of the structure and magnetic properties of Pr2(Fe,Co)14(C,B)-type nanocomposites
Authors: Li A. H. , Chiu C. H. , Chang H. W. , Chang W. C. , Li W.
Published: August 2005

The structure and magnetic properties of Pr9+xFe73−x−yTiyCo10B4C4 (x=0,0.5,1,1.5; y=0,2) melt-spun ribbons have been investigated. All these ribbons consist mainly of three phases, namely, 2:14:1, α-(Fe,Co), and 2:17 phases. It was found that the grain size of these phases decreases with increasing Pr content. A small substitution of Ti for Fe suppresses the grain growth of α-(Fe,Co) phase. The intergranular exchange coupling remarkably increases with increasing Pr and Ti substitution. For Ti-free Pr9+xFe73−xCo10B4C4 ribbons, the Hci increases, and Br decreases, but (BH)max nearly keeps invariable up to x=1.0, then slightly increases, with increasing x. A Br of 9.1kG, Hci of 10.0kOe, and (BH)max of 12.5MGOe were obtained in Pr10.5Fe71.5Co10B4C4. The coercivity and demagnetization-curve shape are substantially improved with Ti substitution, without a sacrifice of remanence (except for x=0). The (BH)max increases by a large amount (∼5MGOe) with a small substitution (2at.%) of titanium. A Br of 9.6kG, Hci of 10.2kOe, and (BH)max of 17.4MGOe have been achieved in Pr10.5Fe69.5Ti2Co10B4C4 ribbon.
Complete decomposition of polymers by means of thermally generated holes at high temperatures in titanium dioxide and its decomposition mechanism
Authors: Shinbara Toshihiro , Makino Takashi , Matsumoto Keiji , Mizuguchi Jin
Published: August 2005

Thermoplastic as well as thermosetting polymers are found to be completely decomposed in the presence of titanium dioxide due to thermally excited holes at high temperatures. The decomposition mechanism has therefore been investigated in terms of thermal analysis, electron-spin resonance, and infrared spectra, using polycarbonate (PC) as the model substance. The initial stage of the decomposition is the electron capture from PC by means of thermally generated holes at the TiO2∕PC interface to create radicals in PC. Then, the radicals propagate throughout the PC chains to rupture the chemical bond between monomer units, leading to the remarkable reduction in molecular weight. Finally, the decomposition within the monomer unit takes place at the CH3 site to give small fragments. These fragments end up with complete combustion in the presence of oxygen to give H2O and CO2.
Renouncing electroneutrality is not free of charge: Switching on electrogenicity in a Na
+
-coupled phosphate cotransporter
Authors: Bacconi Andrea , Virkki Leila V. , Biber Jürg , Murer Heini , Forster Ian C.
Published: August 2005

Renal type IIa Na
+
-coupled inorganic phosphate (P
i
) cotransporters (NaPi-IIa) mediate divalent P
i
transport in an electrogenic manner, whereas the renal type IIc isoform (NaPi-IIc) is electroneutral, yet it shows high sequence identity with NaPi-IIa. Dual uptake (
32
P
i
/
22
Na) assays confirmed that NaPi-IIc displayed Na
+
-coupled P
i
cotransport with a 2:1 (Na
+
:P
i
) stoichiometry compared with 3:1 established for NaPi-IIa. This finding suggested that the electrogenicity of NaPi-IIa arises from the interaction of an additional Na
+
ion compared with NaPi-IIc. To identify the molecular elements responsible for the functional difference between isoforms, we used chimera and amino acid replacement approaches. Transport activity of chimeras constructed with NaPi-IIa and NaPi-IIc indicated that residues within the first six transmembrane domains were essential for the electrogenicity of NaPi-IIa. Sequence comparison between electrogenic and electroneutral isoforms revealed differences in the charge and polarity of residues clustered in three areas, one of which included part of the predicted third transmembrane domain. Here, substitution of three residues with their NaPi-IIa equivalents in NaPi-IIc (S189A, S191A, and G195D) resulted in a transporter that displayed a 1:1 charge/P
i
coupling, a 3:1 Na
+
:P
i
stoichiometry, and transient currents that resembled pre-steady-state relaxations. The mutant's weaker voltage dependency and 10-fold lower apparent P
i
affinity compared with NaPi-IIa indicated that other residues important for the NaPi-IIa kinetic fingerprint exist. Our findings demonstrate that, through a minimal number of side chain substitutions, we can effect a switch from electroneutral to electrogenic cotransporter function, concomitant with the appearance of a cosubstrate interaction site.
Electrode diagnostics and modelling for ceramic metal halide lamps
Authors: Luijks G M J F , Nijdam S , Esveld H v
Published: August 2005

Electrode temperature diagnostics and a two-dimensional electrode model have been developed to improve our understanding of electrode behaviour in ceramic metal halide lamps. Using transparent YAG arc tubes in dc and ac operation, anode and cathode characteristics, like the effective work function, anode fall and electrode input power, could be derived from the measured temperature profiles. It is found that Dy-iodide in the metal halide lamp filling has a strong so-called gas-phase emitter effect. In order to improve our understanding of the observed phenomena and to help design electrodes for future lamps, a rotational symmetric two-dimensional electrode model has been created. The model is completely phase resolved so that time-dependent effects can be studied (both ac and dc). Furthermore, it contains various options for calculating the power input distribution, including a complex cathode sheath model as well as a simple anode model. The model has been shown to predict spot/diffuse transitions (in Hg-lamps with heavy electrodes/low currents) very similar to the behaviour seen in real lamps.
What Do Microbes Encounter at the Plant Surface? Chemical Composition of Pea Leaf Cuticular Waxes
Authors: Gniwotta Franka , Vogg Gerd , Gartmann Vanessa , Carver Tim L.W. , Riederer Markus , Jetter Reinhard
Published: August 2005

In the cuticular wax mixtures from leaves of pea (Pisum sativum) cv Avanta, cv Lincoln, and cv Maiperle, more than 70 individual compounds were identified. The adaxial wax was characterized by very high amounts of primary alcohols (71%), while the abaxial wax consisted mainly of alkanes (73%). An aqueous adhesive of gum arabic was employed to selectively sample the epicuticular wax layer on pea leaves and hence to analyze the composition of epicuticular crystals exposed at the outermost surface of leaves. The epicuticular layer was found to contain 74% and 83% of the total wax on adaxial and abaxial surfaces, respectively. The platelet-shaped crystals on the adaxial leaf surface consisted of a mixture dominated by hexacosanol, accompanied by substantial amounts of octacosanol and hentriacontane. In contrast, the ribbon-shaped wax crystals on the abaxial surface consisted mainly of hentriacontane (63%), with approximately 5% each of hexacosanol and octacosanol being present. Based on this detailed chemical analysis of the wax exposed at the leaf surface, their importance for early events in the interaction with host-specific pathogenic fungi can now be evaluated. On adaxial surfaces, approximately 80% of Erysiphe pisi spores germinated and 70% differentiated appressoria. In contrast, significantly lower germination efficiencies (57%) and appressoria formation rates (49%) were found for abaxial surfaces. In conclusion, the influence of the physical structure and the chemical composition of the host surface, and especially of epicuticular leaf waxes, on the prepenetration processes of biotrophic fungi is discussed.
A Plant-Specific Protein Essential for Blue-Light-Induced Chloroplast Movements
Authors: DeBlasio Stacy L. , Luesse Darron L. , Hangarter Roger P.
Published: August 2005

In Arabidopsis (Arabidopsis thaliana), light-dependent chloroplast movements are induced by blue light. When exposed to low fluence rates of light, chloroplasts accumulate in periclinal layers perpendicular to the direction of light, presumably to optimize light absorption by exposing more chloroplast area to the light. Under high light conditions, chloroplasts become positioned parallel to the incoming light in a response that can reduce exposure to light intensities that may damage the photosynthetic machinery. To identify components of the pathway downstream of the photoreceptors that mediate chloroplast movements (i.e. phototropins), we conducted a mutant screen that has led to the isolation of several Arabidopsis mutants displaying altered chloroplast movements. The plastid movement impaired1 (pmi1) mutant exhibits severely attenuated chloroplast movements under all tested fluence rates of light, suggesting that it is a necessary component for both the low- and high-light-dependant chloroplast movement responses. Analysis of pmi1 leaf cross sections revealed that regardless of the light condition, chloroplasts are more evenly distributed in leaf mesophyll cells than in the wild type. The pmi1-1 mutant was found to contain a single nonsense mutation within the open reading frame of At1g42550. This gene encodes a plant-specific protein of unknown function that appears to be conserved among angiosperms. Sequence analysis of the protein suggests that it may be involved in calcium-mediated signal transduction, possibly through protein–protein interactions.
Cosuppression of Eukaryotic Release Factor 1-1 in Arabidopsis Affects Cell Elongation and Radial Cell Division
Authors: Petsch Katherine Anne , Mylne Joshua , Botella José Ramón
Published: August 2005

The role of the eukaryotic release factor 1 (eRF1) in translation termination has previously been established in yeast; however, only limited characterization has been performed on any plant homologs. Here, we demonstrate that cosuppression of eRF1-1 in Arabidopsis (Arabidopsis thaliana) has a profound effect on plant morphology, resulting in what we term the broomhead phenotype. These plants primarily exhibit a reduction in internode elongation causing the formation of a broomhead-like cluster of malformed siliques at the top of the inflorescence stem. Histological analysis of broomhead stems revealed that cells are reduced in height and display ectopic lignification of the phloem cap cells, some phloem sieve cells, and regions of the fascicular cambium, as well as enhanced lignification of the interfascicular fibers. We also show that cell division in the fascicular cambial regions is altered, with the majority of vascular bundles containing cambial cells that are disorganized and possess enlarged nuclei. This is the first attempt at functional characterization of a release factor in vivo in plants and demonstrates the importance of eRF1-1 function in Arabidopsis.
Lateral Diffusion of CO2 in Leaves Is Not Sufficient to Support Photosynthesis
Authors: Morison James I.L. , Gallouët Emily , Lawson Tracy , Cornic Gabriel , Herbin Raphaèle , Baker Neil R.
Published: August 2005

Lateral diffusion of CO2 was investigated in photosynthesizing leaves with different anatomy by gas exchange and chlorophyll a fluorescence imaging using grease to block stomata. When one-half of the leaf surface of the heterobaric species Helianthus annuus was covered by 4-mm-diameter patches of grease, the response of net CO2 assimilation rate (A) to intercellular CO2 concentration (Ci) indicated that higher ambient CO2 concentrations (Ca) caused only limited lateral diffusion into the greased areas. When single 4-mm patches were applied to leaves of heterobaric Phaseolus vulgaris and homobaric Commelina communis, chlorophyll a fluorescence images showed dramatic declines in the quantum efficiency of photosystem II electron transport (measured as Fq′/Fm′) across the patch, demonstrating that lateral CO2 diffusion could not support A. The Fq′/Fm′ values were used to compute images of Ci across patches, and their dependence on Ca was assessed. At high Ca, the patch effect was less in C. communis than P. vulgaris. A finite-volume porous-medium model for assimilation rate and lateral CO2 diffusion was developed to analyze the patch images. The model estimated that the effective lateral CO2 diffusion coefficients inside C. communis and P. vulgaris leaves were 22% and 12% of that for free air, respectively. We conclude that, in the light, lateral CO2 diffusion cannot support appreciable photosynthesis over distances of more than approximately 0.3 mm in normal leaves, irrespective of the presence or absence of bundle sheath extensions, because of the CO2 assimilation by cells along the diffusion pathway.
Two FAD3 Desaturase Genes Control the Level of Linolenic Acid in Flax Seed
Authors: Vrinten Patricia , Hu Zhiyuan , Munchinsky Mary-Ann , Rowland Gordon , Qiu Xiao
Published: August 2005

Industrial oil flax (Linum usitatissimum) and edible oil or solin flax differ markedly in seed linolenic acid levels. Despite the economic importance of low-linolenic-acid or solin flax, the molecular mechanism underlying this trait has not been established. Two independently inherited genes control the low-linolenic-acid trait in flax. Here, we identified two genes, LuFAD3A and LuFAD3B that encode microsomal desaturases capable of desaturating linoleic acid. The deduced proteins encoded by these genes shared 95.4% identity. In the low-linolenic-acid line solin 593-708, both LuFAD3A and LuFAD3B carry point mutations that produce premature stop codons. Expression of these genes in yeast (Saccharomyces cerevisiae) demonstrated that, while the wild-type proteins were capable of desaturating linoleic acid, the truncated proteins were inactive. Furthermore, the low-linolenic-acid phenotype in flax was complemented by transformation with a wild-type gene. Codominant DNA markers were developed to distinguish between null and wild-type alleles of both genes, and linolenic acid levels cosegregated with genotypes, providing further proof that LuFAD3A and LuFAD3B are the major genes controlling linolenic acid levels in flax. The level of LuFAD3 transcripts in seeds peaked at about 20 d after flowering, and transcripts were not detectable in leaf, root, or stem tissue. A dramatic reduction in transcript levels of both genes occurred in the low-linolenic-acid solin line, which was likely due to nonsense-mediated decay.
Nitrogen Deprivation Stimulates Symbiotic Gland Development in Gunnera manicata
Authors: Chiu Wan-Ling , Peters Gerald A. , Levieille Germain , Still Patrick C. , Cousins Sarah , Osborne Bruce , Elhai Jeff
Published: August 2005

Gunnera is the only genus of angiosperms known to host cyanobacteria and the only group of land plants that hosts cyanobacteria intracellularly. Motile filaments of cyanobacteria, known as hormogonia, colonize Gunnera plants through cells in the plant's specialized stem glands. It is commonly held that Gunnera plants always possess functional glands for symbiosis. We found, however, that stem gland development did not occur when Gunnera manicata plants were grown on nitrogen (N)-replete medium but, rather, was initiated at predetermined positions when plants were deprived of combined N. While N status was the main determinant for gland development, an exogenous carbon source (sucrose) accelerated the process. Furthermore, a high level of sucrose stimulated the formation of callus-like tissue in place of the gland under N-replete conditions. Treatment of plants with the auxin transport inhibitor 1-naphthylphthalamic acid prevented gland development on N-limited medium, most likely by preventing resource reallocation from leaves to the stem. Optimized conditions were found for in vitro establishment of the Nostoc-Gunnera symbiosis by inoculating mature glands with hormogonia from Nostoc punctiforme, a cyanobacterium strain for which the full genome sequence is available. In contrast to uninoculated plants, G. manicata plants colonized by N. punctiforme were able to continue their growth on N-limited medium. Understanding the nature of the Gunnera plant's unusual adaptation to an N-limited environment may shed light on the evolution of plant-cyanobacterium symbioses and may suggest a route to establish productive associations between N-fixing cyanobacteria and crop plants.
TPK1 Is a Vacuolar Ion Channel Different from the Slow-Vacuolar Cation Channel
Authors: Bihler Hermann , Eing Christian , Hebeisen Simon , Roller Anja , Czempinski Katrin , Bertl Adam
Published: August 2005

TPK1 (formerly KCO1) is the founding member of the family of two-pore domain K+ channels in Arabidopsis (Arabidopsis thaliana), which originally was described following expression in Sf9 insect cells as a Ca2+- and voltage-dependent outwardly rectifying plasma membrane K+ channel. In plants, this channel has been shown by green fluorescent protein fusion to localize to the vacuolar membrane, which led to speculations that the TPK1 gene product would be a component of the nonselective, Ca2+ and voltage-dependent slow-vacuolar (SV) cation channel found in many plants species. Using yeast (Saccharomyces cerevisiae) as an expression system for TPK1, we show functional expression of the channel in the vacuolar membrane. In isolated vacuoles of yeast yvc1 disruption mutants, the TPK1 gene product shows ion channel activity with some characteristics very similar to the SV-type channel. The open channel conductance of TPK1 in symmetrically 100 mm KCl is slightly asymmetric with roughly 40 pS at positive membrane voltages and 75 pS at negative voltages. Similar to the SV-type channel, TPK1 is activated by cytosolic Ca2+, requiring micromolar concentration for activation. However, in contrast to the SV-type channel, TPK1 exhibits strong selectivity for K+ over Na+, and its activity turned out to be independent of the membrane voltage over the range of ±80 mV. Our data clearly demonstrate that TPK1 is a voltage-independent, Ca2+-activated, K+-selective ion channel in the vacuolar membrane that does not mediate SV-type ionic currents.