bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Organic Manure of Nitrogen Nutrients on Economic Benefits of Wheat (Triticum aestivum)
Authors: Kumar Rohit , Sulekha . , Yadav K.K , Singh Lovepreet , Saharan Karanveer
Published: April 2024

A field experiment was conducted at crop research center of IFTM University Moradabad (U.P.) field experiment carried out during the Rabi season 2022–2023. The texture of the sandy loam soil in the experimental field was sandy loam. The randomized block design method was used for the statistical analysis, and the ten treatments included three replications of the application of biofertilizers and V.C. FYM. Treatments were T1 (control), T2 (Pressmud @ 10 t ha-1 + PSB + Azotobactor), T3 (Pressmud @ 10 t ha-1 + PSB), T4 (FYM @ 10 t ha-1 + PSB + Azotobactor), T5 (FYM @ 10 t ha-1 + PSB ), T6 (VC @ 5 t ha-1  + PSB) T7 (VC @ 5 t ha-1 +PSB+Azotobactor), T8 (50%N Through  FYM+50% Through NPK), T9 (75%N Through FYM+25%Through NPK) T10 (100% NPK 120:60:40)  wheat variety DBW90 was sown on during December  2022. The levels of NPK fertilizer were associated with a rise in the economic benefits. The outcome showed that, under the treatment 100% NPK of RDF T10, the highest gross return of Rs. 111061 of  ha-1, the highest net return of  Rs. 74821 of ha-1, and the maximum benefit of cost ratio 2.06 were all recorded. When it came to economics, the treatment that used 100% NPK of RDF was found to be superior and statistically comparable to T8. It is also possible to maintain soil fertility, which is crucial for sustainable crop production, by applying organic matter and fertilizers in conjunction with inorganic ones.
Digital Image Authenticity Assessment Using Deep Learning
Authors: Sai G Mohan , Noel B Olive , Kiran B L Sai , Krishna B Karthik , Bhupal M Ram
Published: April 2024

Its super important to find fake pictures online to make sure things are true so we came up with a smart idea using something called a convolutional neural network, CNN is like a really smart detective for pictures. It checks out lots of pictures, some real and some fake and learns how to tell them apart by looking at all the tiny details Before the detective work, we make all the pictures the same size, like putting them in the same-sized frame We also use a special tool called error level analysis (Ela). Ela helps us by showing parts of the pictures that might have been changed its like searching for clues in a detective movie We looked at a bunch of pictures, over 12,000 of them We made sure to have a mix of real ones like trees and people 7492 of them and some that were changed to trick people, 5123 of them this way, our detective could learn from lots of different situations our system is really good at finding fake pictures because it uses fancy math and clever techniques We tested it a lot to make sure it works in different situations, like when someone copies part of a picture or changes how it looks and guess what? Our tests showed that our system is great at finding fakes In the end, our idea helps make sure pictures online are real, which is super important in today’s world of digital pictures.
Effect of Gas-Oil Ratio on Oil Production for a Niger Delta Well
Authors: Okalla Christian Emelu , West Tiya Kristiana , Dike Chukwuebuka Francis , Kerunwa Anthony , Ndoma-egba Lilian Eyang
Published: April 2024

This study delves into the intricate relationship between gas-oil ratio (GOR) and oil production rate in a vertical well within the framework of reservoir engineering. The investigation employs advanced reservoir modeling techniques, drawing insights from Prosper software simulations and well data analysis. A comprehensive methodology involving PVT data, inflow performance relationship data, and sensitivity analysis guides the exploration of GOR's impact on oil rate. The selected well configuration, a vertical well, serves as the experimental canvas for this study. Through meticulous analysis of reservoir and well data, an Inflow Performance Relationship (IPR) curve emerges. This curve is developed using the Darcy reservoir model available within the Prosper software, reflecting the intricate interplay between fluid dynamics, pressure gradients, and production behavior. Further expanding the analysis, the study explores the IPR-Vertical Lift Performance (VLP) curve, spotlighting the well's behavior at a top node pressure of 250 psig. Subsequently, the study dives into the realm of sensitivity analysis, seeking to unravel the nuanced connection between oil rate, GOR, and well head pressure. The captivating findings are encapsulated, a visual testament to the intricate dance of fluid dynamics. The results paint a vivid picture of the GOR's role in oil rate modulation. The correlation between GOR and oil rate is revealed to be a delicate balance, illustrated by a crescendo and diminuendo as GOR rises beyond the bubble point. Above the bubble point, the gas's continuous expansion within the solution propels oil production. The study's intricate examination of well head pressure offers further illumination. The result further exposes the inverse relationship between well head pressure and oil production rate, as heightened well head pressure curtails pressure drawdown and subsequently reduces the amount of oil lifted to the surface. The study concluded that Oil production rate increases with increase in gas-oil ratio up to a maximum above which oil production starts decreasing. The decrease in oil production starts when gas is released from the oil. An increase in well head pressure led to a decrease in oil production. This is attributed to a decrease in pressure drawdown between the bottom of the well and the well head.
Analisa Keprofesionalan dan K3 dalam Manajemen Waste pada Proyek Konstruksi Rumah Tinggal di Surabaya
Authors: Kresnadi Daniel Mulyono , Hermawan Surya , Prasetyo Susmarsongko Budi
Published: April 2024

Salah satu material dalam proyek konstruksi yang sering digunakan adalah besi beton bertulang. Pengelolaan material yang kurang efisien dalam proyek konstruksi akan menimbulkan pemborosan material dan timbunan waste material yang berlebihan sehingga menyebabkan naiknya biaya proyek dan dapat membahayakan Keselamatan dan Kesehatan Kerja (K3) para pekerja konstruksi. Penelitian ini bertujuan untuk menganalisis upaya untuk meminimalkan waste dari pemotongan tulangan dengan tetap memperhatikan K3. Upaya untuk meminimalkan waste besi beton bertulang adalah dengan melakukan optimasi dengan metode integer linear programming dengan bantuan program MATLAB. Data yang digunakan adalah Proyek Konstruksi rumah tinggal dua lantai di Surabaya. Hasil dari proses optimasi adalah 31 pola pemotongan yang digunakan untuk mengurangi waste dari 112 pola pemotongan yang dihasilkan. Penggunaan besi beton bertulang diameter 10 mm dapat dihemat sebanyak 5 lonjor atau 4,032% dengan waste sebesar 10,09 m. Upaya untuk menjaga K3 adalah dengan menggunakan Alat Pelindung Diri (APD) dan memperhatikan peletakkan waste agar tidak membahayakan pekerja. Penelitian ini berhasil mengoptimasi pemotongan tulangan dengan mengurangi waste sebesar 4,032% dengan tetap memperhatikan K3.
Perancangan Sistem Penjadwalan Perawatan Yang Mendukung Total Productive Maintenance Di P.T. X
Authors: Wahjudi Didik , Lim Resmana , Budi Evander
Published: April 2024

P.T. X yang memproduksi timba plastik memiliki Overall Equipment Effectiveness awal sangat rendah. Selain itu, divisi perawatan perusahaan melakukan perawatan tanpa adanya jadwal perawatan yang pasti sehingga pekerja hanya mengandalkan pengalaman mereka. Penelitian ini berfokus pada pembuatan jadwal perawatan preventif yang mendukung penerapan delapan pilar Total Productive Maintenance. Upaya perbaikan tersebut diharapkan dapat meningkatkan nilai OEE. Langkah awal yang dilakukan ialah memilih obyek mesin yang kritis sesuai dengan informasi dari pihak manajemen perusahaan. Langkah berikutnya adalah melakukan perhitungan nilai OEE berdasarkan data arsip laporan produksi pada mesin yang dipilih. Dari perhitungan OEE dan six big losses diperoleh kerugian apa yang paling dominan terjadi pada mesin tersebut. Hasil identifikasi kerugian tersebut dipakai sebagai patokan untuk membuat sistem penjadwalan perawatan  dan upaya perbaikan lain yang mendukung implementasi TPM. Setelah jadwal perawatan tersebut diterapkan bersama dengan usulan-usulan perbaikan lainnya, penulis melakukan pengumpulan data pasca penerapan perbaikan. Dari data yang terbaru didapatkan peningkatan nilai OEE menjadi 61,91%.
Optimalisasi Pemakaian HDPE dan PP Sebagai Pengganti Sebagian Agregat Kasar Terhadap Kuat Tarik dan Kuat Tekan Beton
Authors: Seran Markus Dupri , Setiadji Julius Sentosa
Published: April 2024

Semakin meningkatnya perkembangan teknologi baik di bidang infrastruktur maupun non infrastruktur, maka kebutuhan akan prasarana seperti gedung, jalan, jembatan, dan prasarana lain pada saat ini pun terus meningkat. Kebutuhan akan mutu dan jenis beton pun bervariasi sesuai permintaan di lapangan. Tujuan penelitian ini adalah mengoptimalisasi dan mengevaluasi seberapa besar kemampuan beton dengan penggantian sebagian agregat kasar (split) oleh agregat kasar plastik (HDPE) dan (PP) terhadap kuat tarik dan kuat tekan beton.  Penelitian ini menggunakan metode eksperimen di Laboratorium dengan membuat benda uji berupa silinder beton dengan ukuran diameter 15 cm dan tinggi 30 cm untuk pengujian kuat taik dan kuat tekan beton. Kemudian dilakukan pengujian kuat tarik dan kuat tekan beton pada umur 28 hari dengan menggunakan Mesin CTM (Compression Testing Machine) setelah melalui tahap perawatan (curing). Hasil penelitian menunjukkan bahwa nilai slump adukan beton terus mengalami peningkatan seiring dengan peningkatan persentase penggantian agregat kasar (split) dengan agregat kasar plastik yaitu berkisar antara 9,50 – 14,2 cm akibatnya kadar air dalam campuran beton meningkat sehingga berpengaruh terhadap mutu beton yang dihasilkan semakin menurun. Semakin meningkat persentase penggantian agregat kasar (split) oleh agregat kasar plastik terhadap campuran beton normal, kuat tekan beton mengalami penurunan sebesar 8% atau sebesar 18,752 Mpa.. Terjadi peningkatan nilai kuat tarik pada persentase campuran 2% kemudian cenderung menurun seiring dengan meningkatnya persentase agregat kasar pengganti pada campuran beton.
Sistem Otomasi & Logging Data pada Electric Batch Heat Treatment
Authors: Chandra Budiman , Khoswanto Handry
Published: April 2024

Efisiensi sangat memegang peranan penting dalam industri manufaktur saat ini. Perusahaan manufaktur dituntut untuk dapat mencapai suatu efisiensi agar dapat bersaing dalam kegiatan manufaktur dengan perusahaan lain salah satunya adalah dengan otomasi dan digitalisasi. Electric Batch Heat Treatment (EBHT) merupakan salah satu proses penting dalam produksi Mill Liner untuk memanaskan baja dalam suhu tertentu untuk menghasilkan produk yang berkualitas. Panas yang dihasilkan oleh Electric Batch harus sesuai mencapai nilai tertentu yang sudah ditetapkan dan menjaga kestabilan suhu yang diinginkan. Selain itu setiap sudut ruangan dalam Electric Batch Heat Treatment harus berada pada rentang suhu yang sama. Proses rekam suhu juga menjadi juru kunci selain sebagai tanda bahwa tidak terjadi pemanasan berlebih atau kurang, juga sebagai bukti bahwa hasil pemanasan baja sudah sesuai seperti yang diinginkan untuk mencapai baku mutu tertentu. Dalam jurnal ini, akan dibahas proses menggunakan Silicon Controlled Rectifier (SCR) untuk mengontrol elemen heater pada EBHT untuk mendapatkan efisiensi dalam pemanasan. Selain itu, proses perekaman akan menggunakan sistem database komputer sehingga perekaman suhu dapat disimpan secara digital.
Karar Ağacı ve Kural Tümevarımı ile Eğitsel Veri Madenciliği: SAÜ İLİTAM Örneği
Authors: Demircioğlu Diren Deniz , Horzum Mehmet Barış
Published: April 2024

Bu çalışma, karma bir lisans tamamlama programına (İLİTAM) kayıt yaptıran öğrencilerin profiline göre, öğrencinin başarılı olma ya da terk etme/başarısız olma durumlarını incelemeyi amaçlamaktadır. Ayrıca öğrenci verilerine ait değişkenlerin öznitelik ağırlıklarına göre öğrencinin başarılı olma ya da terk etme/başarısız olma durumları üzerindeki önem dereceleri de ele alınmıştır. Araştırma yöntemi olarak eğitsel veri madenciliği kapsamında kullanılan CRISP-DM süreç modelinden faydalanılmıştır. Öznitelik ağırlıkları ise bilgi kazanımı yöntemi ile tespit edilmiştir. Araştırmanın çalışma grubu Sakarya Üniversitesi (SAÜ) lisans tamamlama programına 2013-2016 yılları arasında programa giriş yapan öğrencilerden oluşmaktadır. Sistemsel kayıtlardan elde edilen veri seti öğrencinin üniversiteye giriş bilgilerini içermektedir ve buna karşılık hedef değer ise öğrencinin üniversiteden mezuniyet başarı durumları yani başarılı olma ya da terk etme/başarısız olma durumları ile oluşturmuştur. Sonuçlar hedef değere en çok etki eden parametrenin öğrencinin cinsiyeti olduğunu göstermektedir. Ayrıca en yakın komşu algoritması kullanılarak 91.30% tahmin doğruluğu oranıyla bir öğrencinin kayıt yaptırdığında sahip olduğu genel bilgilerine göre mezuniyet başarı durumlarının tahmini gerçekleştirilmiştir. Bu sayede öğrenciye yönelik planlama yapmak ve önerilerde bulunmak mümkün olacaktır. Araştırmada bulgulara yönelik sonuç ve öneriler geliştirilmiştir.
Equilibrium and kinetic study for the removal of malachite green using activated carbon prepared from Borassus flabellofer male flower
Authors: Jagadeesh Babu P. E. , Kumar Vimal , Visvanathan Renuka
Published: July 2009

Activated carbon was prepared from dried Borassus flabellofer male flower and batch adsorption experiments were conducted to study its potential to remove malachite green (MG) dye. The process was further optimized by studying the operating variables like initial pH of the stock solution, activation temperature, initial dye concentration, adsorbent loading and contact time. The optimized pH and activation temperatures were found to be 7.55 and 450 °C respectively, where further analysis was made using these optimal variables. Linear, Freundlich and Langmuir isotherms were studied and it was found that the Langmuir isotherms have the highest correlation coefficients compared to the others. Further, the sorption kinetics were analysed using pseudo‐first‐order and pseudo‐second‐order kinetic models. The data showed that the second‐order equation was the more appropriate, which indicate that the intra‐particle diffusion is the rate limiting factor. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.
Catalytic decomposition of methane over supported Ni catalysts with different particle sizes
Authors: Yunfei Sun , Zhijun Sui , Jinghong Zhou , Ping Li , Xinggui Zhou , De Chen
Published: July 2009

Methane decomposition on γ‐Al2O3‐supported Ni catalysts, as a method for the production of carbon nanofibers (CNFs) and CO‐free hydrogen, has been investigated to show the effect of catalyst particle size on the rate and yield of CNFs formation. The catalysts were prepared by deposition–precipitation with different calcination temperature ranging from 725 to 1025 K so as to have different initial particle sizes. The results show that catalysts with smaller initial particle sizes had higher initial growth rate but experienced fast deactivation. The lifetime of the catalyst, ending at the inflection point on the rate curve of CNFs growth, could well represent the yield of CNFs of the catalyst, and the maximal yield of CNFs was achieved on the Ni catalysts calcinated at 823 K and with a particle size of around 56 nm. However, the diameters of the grown CNFs were not directly related to the initial size of the catalysts, because of particle sintering and breaking during catalyst reduction or CNFs formation. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.
Transdermal drug delivery by coated microneedles: geometry effects on drug concentration in blood
Authors: Al‐Qallaf Barrak , Das Diganta Bhusan , Davidson Adam
Published: July 2009

Drug administration through transdermal delivery is restricted by the top layer of skin, the stratum corneum. One possible solution to overcome the barrier function of the stratum corneum is to employ microneedle arrays. However, detailed theoretical models relating drug‐coated microneedles and their geometry to the drug concentration in the blood are limited. This article aims to address this issue by examining the blood concentration profiles for a model drug, insulin, that has been administered via coated microneedles. A mathematical model is introduced and applied to predict theoretical blood concentrations. Furthermore, the insulin concentration in blood is calculated for a range of different microneedle shapes and dimensions to identify the most effective geometry. The results indicate that the optimum microneedle geometry in terms of maximizing insulin concentration was a rocket‐shaped needle with a constant tip angle of 90°. Also, it has been found that the number of microneedles in an array is the most significant factor in determining maximum insulin concentration in the blood (Cb, max). Penetration depth of the microneedle, centre‐to‐centre spacing and microneedle thickness had a less significant effect on the maximum insulin concentration in the blood. It is envisaged that the current study will help in designing microneedles of optimum size and shape for transdermal drug delivery. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.
Three‐dimensional inversion of automatic resistivity profiling data
Authors: Papadopoulos Nikos G. , Tsokas Gregory N. , Dabas Michel , Yi Myeong‐Jong , Kim Jung‐Ho , Tsourlos Panagiotis
Published: July 2009

Geophysical investigations through mobile multi‐electrode systems, such as the automatic resistivity profiling (ARP) method, can increase the size of the surveyed areas without jeopardizing the spatial resolution of the survey. The representation of the apparent resistivity data in maps corresponding to the different measuring dipoles is sufficient in most routine applications for outlining the buried archaeological structures. In specific cases where a more quantitative interpretation of the apparent resistivity data is demanded, a three‐dimensional resistivity inversion can provide the necessary tool for this purpose.

This work investigates the possibilities and limitations of the three‐dimensional resistivity inversion in processing the ARP data. A three‐dimensional finite element smoothness‐constrained inversion algorithm was used. The active constraint balancing (ACB) method was also applied in order to enhance the stability and the resolving power of the inversion procedure.

Resistivity models that are commonly encountered in archaeological exploration were used to generate synthetic apparent resistivity data using a three‐dimensional finite element forward modelling program. Inversion of the synthetic data showed that the maximum investigation depth of the ARP method is comparable to the length of the larger receiving dipole and cannot exceed the 2–2.5 m for the particular ARP device tested in this work. Archaeological structures buried within this depth range can be effectively mapped, while the resolution of the subsurface structures is related to the data acquisition parameters. The inversion algorithm was also used to reconstruct the three‐dimensional resistivity distribution from the ARP data set collected from the Andilly archaeological site in France. The results effectively showed that the three‐dimensional inversion can act as a complementary tool in acquiring a more quantitative interpretation model of the buried archaeological features. Copyright © 2009 John Wiley & Sons, Ltd.
Determination of a novel diarylheptanoid (Juglanin B) from green walnut husks (Juglans regia L.) in rat plasma by high‐performance liquid chromatography
Authors: Huang Xin‐Yi , Duan Qiu‐Yan , Liu Jun‐Xi , Di Duo‐Long
Published: July 2009

A simple and reliable analytical method based on high‐performance liquid chromatography (HPLC) coupled with a diode array detector (DAD) was developed for the determination of a novel diarylheptanoid (Juglanin B) from green walnut husks (Juglans regia L.) in rat plasma using rhoiptelol as an internal standard. Chromatographic separation was carried out on a Sinochrom ODS‐AP C18 column (250 × 4.6 μm i.d., 5 mm) with acetonitrile–10 mM postassium dihydrogen phosphate (pH = 3; 55:45, v/v) as mobile phase, and the detection wavelength was set at 214 nm. The plasma samples were prepared using methanol as protein precipitator. The extraction recovery of Juglanin B ranged from 70.26 to 78.59%, and the calibration curve had a good linearity in the range 0.08–50 μg/mL (r2 = 0.9932). The RSDs of intra‐ and inter‐day precision ranged from 1.19 to 4.92% and 4.35 to 4.54%, respectively. The HPLC‐DAD method described is a simple, rapid and reliable method for the determination of Juglanin B level and for use in studies involving pharmacokinetics. Copyright © 2009 John Wiley & Sons, Ltd.
Catalytic Oxidative Decarboxylation of Some Benzylcarboxylic Acid Derivatives by a New Iron(III) Schiff Base Complex
Authors: MONTAZEROZOHORI Morteza , NASR‐ESFAHANI Masoud , AKHLAGHI Parisa
Published: July 2009

A quadridentate Schiff base ligand of N,N′‐bis(2‐hydroxy‐α‐methylbenzylidene)ethylenediamine (HMBEDA) and its new iron(III) complex were synthesized and identified by analytical, spectral data (1H NMR, 13C NMR FT‐IR and UV‐visible) and molar conductance. A rapid and efficient homogeneous oxidative decarboxylation of some benzylcarboxylic acid derivatives was carried out by a catalytic amount of iron(III) Schiff base complex in chloroform, using tetrabutylammonium periodate as a mild oxidant in good to excellent yields at room temperature.
Asymmetric Epoxidation of Terminal Olefins with Binaphthyl Strapped Porphyrin Catalysts: (‐( Stacking Interaction and Steric Effects on the Enantioselectivities
Authors: REN Qizhi , WANG Aiqing , LIU Shuangyan , DING Xiaojian
Published: July 2009

Two binaphthyl strapped porphyrins with similar chiral auxiliaries 1b and 2b were used as efficient catalysts for asymmetric epoxidation of both styrene derivatives and non‐aromatic olefin substrates. Theoretical calculation of styrene approach to both catalysts has been performed. The subtle difference of the chiral cavities between two porphyrins has been analyzed by 1H NMR. The π‐π stacking interaction between aromatic substrates and catalysts might be one factor for the dramatic different enantioselectivities. Besides, the steric effect of the binaphthyl handle of 1b and 2b also causes the high ee values for non‐aromatic olefin epoxidations.
Combinatorial Approach to Synthesize and Optimize Gd2O3:Tb Nanocrystals
Authors: ZHANG Xiaoyu , WU Qingsheng
Published: July 2009

Combinatorial approach was first used to synthesize and optimize luminescent Gd2O3:Tb nanocrystals. Orthogonal Design was used to investigate their properties comprehensively. The megascopic photoluminescence properties have been observed under ultraviolet light by a 254 nm laser. The structural properties of Gd2O3:Tb were further studied and optimized by X‐ray diffraction and transmission electron microscopy. The visible luminescence spectra were investigated under excitation by a 284 nm laser. Glutin reaction process was discussed as the possible mechanisms. Finally, the optimized sample was obtained with the best properties in some scope.
Synthesis and Biological Activities of Schiff Bases of 3‐Amino‐1H‐1,2,4‐triazole
Authors: SUN Xiaohong , LIU Yuanfa , CHEN Shuzhe , CHEN Bang , JIA Yingqi , ZENG Zhengfang
Published: July 2009

Eight Schiff bases of 3‐amino‐1H‐1,2,4‐triazole have been synthesized by glacial acetic acid catalyzed condensation of 3‐amino‐1H‐1,2,4‐triazole with substituted benzaldehyde and structurally confirmed by IR, 1H NMR and elemental analysis. The preliminary bioassay showed that the title compounds exhibited good fungicidal activities.
An Efficient Method for Racemization of (S)‐3‐Carbamoylmethyl‐5‐methylhexanoic Acid
Authors: WU Ting , GAO Man , YE Bo , SHEN Yongjia
Published: July 2009

(S)‐3‐Carbamoylmethyl‐5‐methylhexanoic acid was heated in xylene and converted into 4‐isobutyl‐piperidine‐ 2,6‐dione, which was hydrolyzed in aqueous solution of sodium hydroxide to afford the racemate. Our process is much advantageous over the traditional one, with not only less time (ca. 20 h) but also higher yield (76.4%).
Synthesis and Reactivity of Group 6 Metal Carbonyl Complexes with Bis(pyrazol‐1‐yl)methanes Modified by the Vinyltin Groups
Authors: WEN Zhenkang , YANG Zhi , SONG Haibin , TANG Liangfu
Published: July 2009

Diphenyl(vinyl)stannylbis(3,5‐dimethylpyrazol‐1‐yl)methane and diphenyl(vinyl)stannylbis(3,4,5‐trimethyl‐ pyrazol‐1‐yl)methane have been synthesized by the reaction of bis(3,5‐dimethylpyrazol‐1‐yl)methyl or bis(3,4,5‐ trimethylpyrazol‐1‐yl)methyllithium with diphenyl(vinyl)tin iodide. Treatment of these bis(pyrazol‐1‐yl)methanes modified by the vinyltin groups with M(CO)5THF (M=Mo and W) in refluxing THF resulted in new heterobimetallic complexes R3SnCHPz2M(CO)3 (R3Sn represents trivinyltin or diphenyl(vinyl)tin, and Pz represents substituted pyrazol‐1‐yl), in which a vinyl group bonds to the molybdenum or tungsten atom in η2‐fashion to lead to bis(pyrazol‐1‐yl)methanes acting as a tridentate κ3‐(π,N,N) ligand. Reaction of (CH2=CH)3SnCH(3,5‐Me2Pz)2W(CO)3 and Ph2(CH2=CH)SnCH(3,5‐Me2Pz)2W(CO)3 with I2 has been investigated. The former gave a complex CH2(3,5‐Me2Pz)2W(CO)4, while the latter yielded a four‐membered heterometallocyclic complex CH(3,5‐Me2Pz)2W(CO)3I with the loss of the organotin group. Treatment of this four‐membered heterometallocyclic complex with PhSNa led to the iodide anion replaced by the thiophenolate anion to give a complex CH(3,5‐Me2Pz)2W(CO)3SPh.
A clinical approach to exercise tolerance testing in coronary artery disease
Authors: Mills R. M. , Greenberg J. M.
Published: July 2009

Data from exercise tolerance testing should be incorporated into clinical decision making. A strategy for stratification of individual patients into high, indeterminate, and low‐risk categories using Bruce protocol exercise testing is outlined. This approach will help to ensure further evaluation of high‐risk individuals without excessive testing of patients having excellent long‐term prognoses.
Significance of hypertension in childrend
Authors: Levin S. E.
Published: July 2009

This article does not consider the secondary causes of high blood pressure in children. Essential hypertension is a major factor in the morbidity and mortality from cardiovascular disease among adult populations throughout the world. The possibility that a raised blood pressure may have its origins in childhood or even in infancy is being extensively explored. Accurate measurement of blood pressure—especially systolic—is now feasible, by the Doppler technique, in very young children. The concept of “tracking” of blood pressure has been investigated. In addition, factors such as familial aggregation, genetic aspects, and the role of obesity in the etiology of hypertension have been considered. The reason for differences in the severity of manifestation of hypertension in black and white populations has not been satisfactorily elucidated, despite a number of childhood population studies. With an increased number of blood pressure measurements more children are being discovered with labile or even essential hypertension. The exact level above which to consider therapy is somewhat controversial. Nevertheless, even with mild persistent elevations, nonpharmacologic measures such as control of obesity, reduction in salt intake, regular exercise, potassium supplementation, and relaxation therapy, seem warranted. These measures should also be seriously considered in the prevention of hypertension in young urban populations.
High dose intravenous streptokinase in acute myocardial infarction
Authors: Neuhaus K. L. , Tebbe U. , Sauer G. , Kreuzer H. , Köstering H.
Published: July 2009

Early recanalization of infarct‐related coronary arteries has been attempted in 40 patients with acute myocardial infarction (AMI) and angiographically proven total occlusion by brief high dose intravenous streptokinase infusion (IVSK). In 24 patients (60%) recanalization was achieved after 48± 14 min of IVSK at an infusion rate of 30, 000 to 40, 000 IU/min (group A), in 16 patients there was a late (>2 h) or no recanalization (group B). The total dose of SK was 1.7±0.48 Mio IU in group A and 1.74±0.41 Mio IU in group B, the time from the onset of symptoms to peak myocardial enzyme of creatine phosphokinase (CKMB) 11 ±3 h in group A and 22±6 h in group B (p<0.001). Biplane left ventricular ejection fraction increased from 55±9% at the time of acute angiography to 58± 10% after 14 to 24 days in group A (p<0.1) and decreased from 49± 11 to 41 ±11% in group B (p<0.005). There were four reocclusions in group A, two could be reopened by i.v. urokinase (1 Mio IU over 30 min). During a follow‐up period of 18±8 months one patient in group A died from an early ventricular rupture 2 hours after recanalization, and one patient in group B from heart failure 7 months after IVSK. There was no serious bleeding or other complication related to IVSK. We conclude that IVSK is an effective and safe means of early recanalization of coronary thrombosis in AMI, and feasible in the majoriity of patients with AMI.
Coronary artery disease in diabetic and nondiabetic patients: A clinical and angiographic comparison
Authors: Wilson C. S. , Gau G. T. , Fulton R. E. , Davis G. D.
Published: July 2009

A comparison of data from 58 diabetic and 58 nondiabetic patients with arteriographic evidence of coronary artery disease showed that diabetic patients had a significantly greater frequency of major stenoses in the intermediate coronary artery segments but no significant differences in the proximal or distal segments. Thus, the diabetic patients did have more severe coronary disease, but the diabetic group did not have “more distal” disease as represented by the number of major or minor lesions in the distal segments. The diabetic patients had a significantly greater frequency of electrocardiographic intraventricular conduction defects and manifestations of left ventricular dysfunction. There was no significant difference in the severity of coronary artery disease between the diabetic patients with manifestations of myocardial decompensation and the diabetic patients without such manifestations, suggesting that the in‐creased frequency of myocardial dysfunction in diabetic patients may be related to factors other than the greater severity of coronary artery disease.
A new microcomputer‐based ecg analysis system
Authors: Kyle M. C. , Conrad J. D. , Freis E. D. , Klingeman J. D. , Pipberger H. V.
Published: July 2009

A new automated ECG system using advances in microprocessor technology and computerized electrocardiography is described. This microcomputer‐based system is self‐contained and mobile. It acquires both the 12‐lead and orthogonal lead (Frank) electrocardiograms and analyzes the latter within minutes. Software includes the program developed in the Veterans Administration which uses advanced statistical classification techniques and a large well‐documented patient data base. Diagnostic probabilities are computed using a Bayesian approach. Diagnostic performance has been tested using independent clinical criteria and found to be quite accurate. This system enables the clinician to immediately review the computer's identifications, measurements, and diagnostic classifications and quickly use these results in clinical decision making. Serial comparisons are readily made since all previous recordings are stored on floppy diskettes. The use of microprocessors in this system makes it economically feasible for practicing physicians.
Acute myocardial infarction with normal coronary arteries. in vivo demonstration of coronary thrombosis during the acute episode
Authors: Fernandez M. S. , Pichard A. D. , Marchant E. , Lindsay J.
Published: July 2009

Two cases with acute myocardial infarction are presented. Both had thrombotic occlusion of the infarct‐related artery. Following successful thrombolysis with streptokinase, coronary angiography was normal. These cases prove that “myocardial infarction with normal coronaries” can be associated with coronary thrombosis in the acute stage.
Terminology and anatomy of angulated coronary arteriography
Authors: Grover M. , Slutsky R. , Higgins C. , Atwood J. E.
Published: July 2009

Angulated views in coronary arteriography have been increasingly utilized because of their superiority in demonstrating lesions not well seen in standard right and left oblique projections. The importance of these angulated views has been repeatedly demonstrated. It is the purpose of this article to review some basic coronary anatomy angulation terminology, and then to describe the particular advantages of the angulated views in coronary arteriography. Illustrations of these particular views of both coronary systems will be provided.
Altered platelet alpha2adrenoreceptors in orthostatic hypotension
Authors: Weiss R. J. , Dix B. R. , Kissner P. Z. , Smith C. B.
Published: July 2009

Alpha2adrenergic agonists have been used to raise blood pressure in patients with idiopathic orthostatic hypotension (IOH). In an attempt to define the mechanism of action of these agents, radioligand binding of [3H]clonidine, an alpha2agonist, and of [3H]yohimbine, an alpha2antagonist, to human platelet membranes from a patient with IOH was performed to determine the maximum number (Bmax) and dissociation constant (Kd) for this receptor. There was a marked decrease in receptor number in this patient when compared to normal subjects. In normal volunteers the specific binding of [3H]clonidine yielded a mean Bmax of 33 ±2 fmol/mg protein and a Kd of 5.5±0.6 nM, while for the patient the Bmaxwas 20 fmol/mg protein and the Kd was 7.4 nM. For [3H]yohimbine binding in normals, the Bmax was 165 ±12 fmol/mg protein and the Kd was 4.0±0.5 nM, whereas for the patient the Bmaxwas 65 fmol/mg protein and the Kd was 12.0 nM. Alpha2adrenergic agonists such as clonidine decrease blood pressure by stimulating central presynaptic alpha2sites, and thus inhibiting sympathetic activity. There are also alpha2adrenergic receptor sites postsynaptically on vascular smooth muscle. The presence of this receptor postsynaptically in a patient with a reduction of the presynaptic inhibitory sites could account for clonidine's pressor activity in patients with IOH. Further study of both alpha2‐adrenergic receptors in patients with IOH may be important in developing an understanding of central and peripheral mechanisms in the control of blood pressure.
Value of exercise electrocardiography to predict additional jeopardized myocardial regions remote from site of previous myocardial infarction
Authors: Bamrah V. S. , Ryan P. A. , Ptacin M. J. , Tristani F. E.
Published: July 2009

In order to evaluate the efficacy of exercise electrocardiography (ECG) to identify jeopardized myocardial regions remote from the site of previous infarction, exercise ECG, left ventriculography, and coronary arteriography were performed in 90 patients with previous transmural myocardial infarction (MI). Of the 90 patients, angiographic studies revealed jeopardized myocardial regions in 47 patients. Exercise ECG correctly identified 32 of these 47 patients for a sensitivity value of 68%. There were 43 patients without any additional jeopardized myocardial regions. Exercise ECG correctly identifed only 24 of these 43 patients for a specificity value of 56%. The sensitivity and specificity values were similar in patients with prior anterior and inferior wall MI. It is concluded that relatively low sensitivity and specificity values preclude the ability of exercise ECG to accurately identify patients with jeopardized myocardial regions distant from the site of previous MI. Moreover, when such patients were correctly detected, exercise ECG was rather poor in localizing these additional jeopardized myocardial areas.
24‐hour blood pressure recording in patients with orthostatic hypotension
Authors: Brevetti G. , Chiariello M. , Bonaduce D. , Canonico V. , Breglio R. , Condorelli M.
Published: July 2009

Continuous intra‐arterial blood pressure measurement and electrocardiograms were obtained in two ambulatory patients with orthostatic hypotension due to autonomic dysfunction. Systolic and diastolic arterial pressure presented marked variations which took place mainly during the day and were related to several physical activities; however, marked falls in blood pressure were also observed during sleep and at the monent of arousal. A peak incidence of hypotensive events was found in the afternoon, mainly in the hours following the afternoon meal. Recording was repeated after 3 weeks of treatment with propranolol, 40 mg t.i.d. In patient 1, beta blockade drastically reduced the number and severity of hypotensive episodes, while propranolol failed to control blood pressure in patient 2, who experienced a higher number of hypotensive events during treatment. Findings of this study may be relevant to the management of patients with orthostatic hypotension and should contribute to a more accurate characterization of blood pressure profile in autonomic dysfunction.
Management of patients after thrombolytic therapy for acute moycardial infarction
Authors: Goldberg R. K. , Levine S. , Fenster P. E.
Published: July 2009

The coronary artery thrombus that causes acute myocardial infarction can be lysed, and reperfusion can be achieved, in the first few hours after infarction. However, the infarct vessel will reocclude in 15–30% of patients, and this event is frequently associated with pain, reinfarction, arrhythmias, or death. The risk of reocclusion is greatest in patients with high‐grade residual stenosis after thrombolysis. Percutaneous coronary an‐gioplasty may be performed safely after thrombolytic therapy. Angioplasty effectively decreases the degree of residual stenosis, and may thereby reduce the risk of reocclusion and consequent ischemic events. However, a substantial proportion of patients with acute infarction are not suitable candidates for angioplasty. Coronary artery bypass surgery has also been safely performed within several days after thrombolytic therapy. Further studies are needed to determine which patients will benefit most from this aggressive approach to acute myocardial infarction.
The usefulness of exercise‐induced QRS axis shift as a predictor of coronary artery disease
Authors: Ogino K. , Fukugi M. , Hirai S. , Kinugawa T. , Hoshio A. , Hasegawa J. , Kotake H. , Mashiba H.
Published: July 2009

The QRS axis of 101 patients with coronary artery disease (CAD) and 57 normal subjects without CAD who underwent coronary arteriograms were measured before and after exercise testing. There was no improvement in the sensitivity of positive axis shifts (15 degrees or greater) for CAD (18%) when compared to the value of positive ST depression (61%). However, the specificity of positive axis shifts for CAD was significantly increased (98%) when compared to the value of positive ST depression (77%). In addition, 39% of those patients with CAD (39 of 101) showed false negative ST depression, but 18% of these patients (7 of 39) showed a positive axis shift. In normal subjects 21% (12 of 57) showed false positive ST depression, but all of the 21% (12 of 12) showed negative axis shift. There was no significant difference in the increments of heart rate between positive ST depression, positive axis shift, and negative ST depression, negative axis shift. No statistical differences in the sensitivity of ST depression and an axis shift for one‐, two‐ and three‐vessel diseases were noted. The specificity of left‐axis shift for the left anterior descending artery lesion was 98% and the specificity of right‐axis shift for the right coronary artery and/or left circumflex artery lesion was 91%. Therefore, the axis shift response is no more sensitive for the detection of CAD than ST depression. However, when a positive axis shift is observed, one can predict two things: the CAD and the localization of the coronary stenosis.
Quantitative grading of exercise stress test for patients with coronary artery disease using multivariate discriminant analysis
Authors: Wasir H. S. , Dev V. , Narula J. , Bhatia M. L.
Published: July 2009

A group of 111 male patients who had undergone maximal or symptom‐limited maximal exercise stress testing for evaluation of coronary artery disease (CAD) were subjected to coronary angiography. Group I comprised 33 patients with normal or single‐vessel disease (SVD), while 78 patients with double‐vessel disease (DVD) or triple‐vessel disease (TVD) formed Group II. On univariate analysis of the exercise test, the following variables were found to be of significance in discriminating between the two groups: age, exercise duration, double product (heart rate × systolic blood pressure) at peak exercise, duration of ST‐segment depression, number of leads showing ST depression, ST depression of 1 mm or more, configuration of the depressed ST segment, and diastolic blood pressure response to exercise. Multivariate analysis however revealed that only the following five variables had significant discriminant power: number of leads showing ST depression, exercise duration, double product, diastolic pressure response, and ST‐segment configuration. On the basis of their relative importance, a regression equation was developed to give a quantitative score to individual patients. A score of less than zero detected multivessel disease (MVD) with high specificity (94%) and sensitivity (70%), while a score of 15 or more almost excluded MVD (sensitivity 87%). The scoring system as reported here improved the exercise stress test interpretation when compared with the conventional reporting system.
Chronic mexiletine therapy for suppression of ventricular arrhythmias
Authors: Duke M.
Published: July 2009

One hundred patients with a 70% or greater reduction of ventricular premature contractions (VPCs) from baseline during 12 weeks of mexiletine therapy were continued on treatment for an additional 9 months. Fifteen patients did not have follow‐up examinations. The response of the remaining 85 patients during this extended period of open‐label mexiletine administration is described. Holter recordings were scheduled at 3‐month intervals during this period. At these examinations, between 69 and 80% of patients maintained the same 70% or greater level of VPC suppression observed at the start of the 9‐month treatment period. Mean and median levels of VPCs/h at each examination were significantly reduced from premexiletine levels throughout the study (p<0.0001). Blood tests and electrocardiographic intervals did not vary. The most frequently used dosage of mexiletine during each 3‐month treatment period was 600 mg/day (50.0‐55.6% of patients). Side effects warranted discontinuation of therapy in 8% (8/97) of patients, while in 25% (22/85), clinical evaluation resulted in a change in dosage level. Within a setting similar to that of clinical practice, long‐term mexiletine administration for non‐life‐threatening ventricular arrhythmias was effective and well tolerated.
Microcomputer‐assisted filing system of cardiac catheterization records using a relational database management system
Authors: Mohri M. , Kikuchi Y. , Sagara T. , Sugihara M.
Published: July 2009

To efficiently store and retrieve cardiac catheterization records, we have developed a computer‐assisted database, which comprises a 16‐bit microcomputer with dual floppy disk drives, a 20 MB random‐access memory, hard disk drive, and a line printer. All program‐mings were accomplished using a relational database management system (R:base 5000, Microrim, Inc.). Data inquiry procedures could be performed with direct operational commands of the system as well as with preprogrammed command files, and final results of searches were printed out with a line printer. The major advantages of the present system described in this report include: (1) the relatively easy and rapid creation of the database, (2) ease of modification of the database structures even after the system design is finished, (3) operational commands in combination with conditional opera‐torts) are flexible and powerful enough to allow the end user to retrieve data based on various kinds of criteria, (4) a high‐level programming language provided by the R:base automates a series of database procedures with relative ease, (5) relational capabilities of the database management system can enhance the possibility of reconstruction of a new data file from a single or several preexisting data files, and (6) the system can be realized at reasonable cost.
Long‐Term morbidity in patients where the initial suspicion of myocardial infarction was not confirmed
Authors: Herlitz J. , Hjalmarson R. , Karlson B. W. , Nyberg G.
Published: July 2009

The morbidity and mortality during a 5‐year follow‐up in thcoronary care unit with chest pain presenting an initial suspicion of acute infarction, but in whom the diagnosis could not be confirmed, is reported. They were divided into four groups: Possible myocardial infarction (29%), angina pectoris (24%), chest pain of uncertain origin (32%), and nonischemic cause of chest pain (15%). The overall 5‐year mortality rate was 13.3 % and did not differ substantially between the four groups. During the 5‐year follow‐up a confirmed myocardial infarction developed in 28% and 22% among patients with the diagnosis possible infarction and angina pectoris, respectively, and in about 10% of the remaining patients. Stroke developed in 4% of patients with possible infarction and in 2‐3% in the remaining subgroups. In all, 59% of the patients were rehospitalized for a mean duration of 30 days in hospital. Among survivors at 5 years, 54% reported chest pain equivalent to angina pectoris and 25% had chest pain daily. A high prevalence of angina pectoris, a high frequency of rehospitalization due to chest pain, and a high consumption of cardiovascular drugs could be found in all four groups.
Prognostic implications of cardiac scintigraphic parameters obtained in the early phase of acute myocardial infarction
Authors: Suzuki A. , Matsushima H. , Satoh A. , Hayashi H. , Sotobata I.
Published: July 2009

A cohort of 76 patients with acute myocardial infarction was studied with infarct‐avid scan, radionuclide ventriculography, and thallium‐201 myocardial perfusion scintigraphy. Infarct area, left ventricular ejection fraction, and defect score were calculated as radionuclide indices of the extent of myocardial infarction. The correlation was studied between these indices and cardiac events (death, congestive heart failure, postinfarction angina, and recurrence of myocardial infarction) in the first postinfarction year. High‐risk patients (nonsurvivors and patients who developed heart failure) had a larger infarct area, a lower left ventricular ejection fraction, and a larger defect score than the others. Univariate linear discriminant analysis was done to determine the optimal threshold of these parameters for distinguishing high‐risk patients from others. Radionuclide parameters obtained in the early phase of acute myocardial infarction were useful for detecting both patients with grave complications and those with poor late prognosis during a mean follow‐up period of 2.6 years.