bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimizations and Practicality of High-Security CSIDH
Authors: Campos Fabio , Chávez-Saab Jorge , Chi-Domínguez Jesús-Javier , Meyer Michael , Reijnders Krijn , Rodríguez-Henríquez Francisco , Schwabe Peter , Wiggers Thom 
Published: April 2024

In this work, we assess the real-world practicality of CSIDH, an isogeny-based non-interactive key exchange. We provide the first thorough assessment of the practicality of CSIDH in higher parameter sizes for conservative estimates of quantum security, and with protection against physical attacks.
This requires a three-fold analysis of CSIDH. First, we describe two approaches to efficient high-security CSIDH implementations, based on SQALE and CTIDH. Second, we optimize such high-security implementations, on a high level by improving several subroutines, and on a low level by improving the finite field arithmetic. Third, we benchmark the performance of high-security CSIDH. As a stand-alone primitive, our implementations outperform previous results by a factor up to 2.53×.
As a real-world use case considering network protocols, we use CSIDH in TLS variants that allow early authentication through a NIKE. Although our instantiations of CSIDH have smaller communication requirements than post-quantum KEM and signature schemes, even our highly-optimized implementations result in too-large handshake latency (tens of seconds), showing that CSIDH is only practical in niche cases.
Broadcast Encryption using Sum-Product decomposition of Boolean functions
Authors: Dupin Aurélien , Abelard Simon 
Published: April 2024

The problem of Broadcast Encryption (BE) consists in broadcasting an encrypted message to a large number of users or receiving devices in such a way that the emitter of the message can control which of the users can or cannot decrypt it.
Since the early 1990s, the design of BE schemes has received significant interest and many different concepts were proposed. A major breakthrough was achieved by Naor, Naor and Lotspiech (CRYPTO 2001) by partitioning cleverly the set of authorized users and associating a symmetric key to each subset. Since then, while there have been many advances in public-key based BE schemes, mostly based on bilinear maps, little was made on symmetric cryptography.
In this paper, we design a new symmetric-based BE scheme, named

Σ
Π

BE, that relies on logic optimization and consensual security assumptions. It is competitive with the work of Naor et al. and provides a different tradeoff: the bandwidth requirement is significantly lowered at the cost of an increase in the key storage.
Kompyuter tarmoqlarida uzatilayotgan axborotni kriptografik himoyalash usuli
Authors: Ganiyev A.A. , Mavlonov O.N. , Shodmonov D.A. , Maxmudov J.I. 
Published: April 2024

Mazkur maqolada Steganografik himoyadagi mavjud kamchiliklarni bartaraf etishda kriptografik himoya mexanizmlari ko‘rib chiqilgan. Steganografiyaning maqsadi maxfiy xabarlarni raqamli kontentlarga hech kim bunday xabarlar mavjudligini aniqlashga imkon bermaydigan tarzda yashirishdan iborat bo‘lib, u maxfiy xabarning tuzilishini o‘zgartirmasdan, maxfiy xabarni ochiq xabar tarkibiga yashiradi. Shuning uchun o‘zgarishni aniqlash murakkab hisoblanadi. Steganografiya usulining bardoshligi ushbu usulning maxfiyligiga bog‘liq bo‘lib, stegotahlil usuli yashirish usulini aniqlashni maqsad qiladi. Steganografik himoyadagi mavjud kamchiliklarni bartaraf etishda kriptografik himoya mexanizmlaridan foydalanish mumkinligini inobatga olgan holda kriptografik-staganografik himoyalash usuli taklif etilgan, ushbu usul asosida ishlab chiqilgan himoya mexanizmi to‘laqonli himoyani ta’minlashi isbotlandi.
Effect of Pruning and Nutrient Levels on Plant Growth of Guava (Psidium guajava) cv. Allahabad Safeda under Meadow Orcharding Allahabad
Authors: Singh Arun Kumar , Singh Devi 
Published: April 2024

A field experiment was conducted to evaluate the effect of pruning and nutrient levels on growth and yield of guava cv. Allahabad Safeda. The treatment consists of four different levels of pruning P0: 00.0cm (Un-pruned plants/ Without Pruning), P1: Pruned at 30cm of the shoot length, P2: Pruned at 40cm of the shoot length and P3: Pruned at 50cm of the shoot length and four different levels of nutrients (NPK) viz., F1: NPK (260:320:260 g/plant) (Control), F2: NPK (220:280:300 g/plant), F3: NPK (300:360:300g/plant) and F4: NPK (340:400:340g/plant). The experiment comprising 16 treatment combinations was laid out in 2-factor Factorial Randomized Block Design (f-RBD) having three replications during 2014-2015 & 2015-2016. Among the different treatments T16:P3(P3: 50cm x F4: 340:400:340 g/plant) was best dose for optimum vegetative growth parameter viz., plant height (cm), number of branches per plant, number of leaves per plant, plant spread (n-s & e-w), stem diameter (mm), stem length (cm) and days to taken new shoot emergence of guava cv. Allahabad safeda.
Ambient air pollution and risk for ischemic stroke and transient ischemic attack
Authors: Lisabeth Lynda D. , Escobar James D. , Dvonch J. Timothy , Sánchez Brisa N. , Majersik Jennifer J. , Brown Devin L. , Smith Melinda A. , Morgenstern Lewis B. 
Published: May 2008

AbstractObjectiveData on the association between air pollution and cerebrovascular disease in the United States are limited. The objective of this study was to investigate the association between short‐term exposure to ambient air pollution and risk for ischemic cerebrovascular events in a US community.MethodsDaily counts of ischemic strokes/transient ischemic attacks (TIAs) (2001–2005) were obtained from the population‐based Brain Attack Surveillance in Corpus Christi (BASIC) Project. Daily particulate matter less than 2.5μm in diameter (PM2.5), ozone (O3), and meteorological data were obtained from Texas Commission on Environmental Quality. To examine the association between PM2.5and stroke/TIA risk, we used Poisson regression. Separate models included same‐day PM2.5, PM2.5lagged 1 to 5 days, and an averaged lag effect. All models were adjusted for temperature, day of week, and temporal trends in stroke/TIA. The effects of O3were also investigated.ResultsMedian PM2.5was 7.0μg/m3(interquartile range, 4.8–10.0μg/m3). There were borderline significant associations between same‐day (relative risk [RR], 1.03; 95% confidence interval [CI], 0.99–1.07 for an interquartile range increase in PM2.5) and previous‐day (RR, 1.03; 95% CI, 1.00–1.07) PM2.5and stroke/TIA risk. These associations were independent of O3, which demonstrated similar associations with stroke/TIA risk (same‐day RR, 1.02; 95% CI, 0.97–1.08; previous‐day RR, 1.04; 95% CI, 0.99–1.09).InterpretationWe observed associations between recent PM2.5and O3exposure and ischemic stroke/TIA risk even in this community with relatively low pollutant levels. This study provides data on environmental exposures and stroke risk in the United States, and suggests future research on ambient air pollution and stroke is warranted. Ann Neurol 2008
Organotin(IV) carboxylates of cyclopropane carboxylic acid and 3‐cyclohexylpropanoic acid: synthesis, characterization and biological activity. The crystal structure of bis(cyclopropanecarboxylato) tetramethyldistannoxane
Authors: Sarma Moumita Sen , Saha Aniruddha , Roy Abhijit 
Published: May 2008

AbstractA series of tri‐ and di‐organotin(IV) derivatives of the types R3SnL, R2SnL2 and [(R2SnL)2O]2 have been synthesized by the reaction of tri‐ and di‐organotin(IV) chloride(s) with sodium cyclopropane carboxylate and sodium 3‐cyclohexylpropanoate. Based on spectroscopic evidence (IR and NMR), all the triorganotin carboxylates were found to be penta‐coordinated in the solid state (except the tricyclohexyltin derivative, which was found to be four‐coordinated) and four‐coordinated in the solution state. Attempted reaction of Me2SnCl2 with sodium cyclopropane carboxylate in 1:2 stoichiometry afforded a bis(dicarboxylato tetraorganodistannoxane) complex, {[Me2Sn(cyclo‐CH2)2CHCOO]2O}2. The X‐ray diffraction of this ‘dimethyltin(IV) complex’ shows that the compound possesses a tetranuclear aggregate with one bridging bidentate and other free organic ester type monodentate carboxylate groups in which each Sn atom has a five‐coordinated geometry. These complexes were also screened for their antifungal activities. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis and structure of novel spirosilanes. Combination of 1,2‐hydroboration and 1,1‐organoboration
Authors: Wrackmeyer Bernd , Khan Ezzat , Kempe Rhett 
Published: May 2008

AbstractThe reaction of tetra(alkyn‐1‐yl)silanes Si(CC‐R1)4 1 [R1 = tBu (a), Ph (b), C6H4‐4‐Me (c)] with 9‐borabicyclo[3.3.1]nonane (9‐BBN) in a 1:2 ratio affords the spirosilane derivatives 5a–c as a result of twofold intermolecular 1,2‐hydroboration, followed by twofold intramolecular 1,1‐organoboration. Intermediates 3a–c, in which two alkenyl‐ and two alkyn‐1‐yl groups are linked to silicon, were identified by NMR spectroscopy. The molecular structure of the spiro compound 5c was determined by X‐ray analysis, and the solution‐state structures of products and intermediates follow conclusively from the consistent NMR spectroscopic data sets (1H, 11B, 13C and 29Si NMR). Copyright © 2008 John Wiley & Sons, Ltd.
Palladium‐catalyzed Heck coupling of 2‐vinylpyridine with aryl chlorides
Authors: Li Ming , Hua Ruimao 
Published: May 2008

AbstractAn efficient PdCl2(PCy3)2‐catalyzed cross‐coupling reaction of 2‐vinylpyridine with aryl chlorides to afford trans‐2‐styrylpyridines with a variety of functional groups on the benzene ring is described. Copyright © 2008 John Wiley & Sons, Ltd.
New biosurfactants based on germylated fatty compounds
Authors: Katir N. , El Kadib A. , Castel A. , Rivière P. , Benmaarouf Z. 
Published: May 2008

AbstractA simple and efficient method for producing amphiphilic germylated compounds has been developed by hydrogermylation of fatty acid methyl esters. The germylated precursors afford a micelle‐type assembly in various solvents as evident by the formation of nano‐objects, micrometer spheres and lamellar forms. This offers a promising route to synthetically useful monomers for structured materials. Copyright © 2008 John Wiley & Sons, Ltd.
Resin‐IV: Synthesis and characterization of terpolymers derived from 2‐hydroxyacetophenone, melamine, and formaldehyde
Authors: Gupta R. H. , Zade A. B. , Gurnule W. B. 
Published: May 2008

AbstractTerpolymer resins (2‐HAMF) were prepared by the condensation of 2‐hydroxyacetophenone and melamine with formaldehyde in the presence of acid catalyst and using varied molar ratios of reacting monomers. Compositions of terpolymers have been determined by elemental analysis. The number average molecular weights (Mn) have been determined by conductometric titration in nonaqueous medium. Viscometric measurements in dimethyl sulfoxide have been carried out with a view to ascertain the characteristic functions and constants. Electronic spectra, infrared and nuclear magnetic resonance spectra were studied to elucidate the structure. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Effects of the die geometry on the expansion of polystyrene foams blown with carbon dioxide
Authors: Xu Xiang , Park Chul B. 
Published: May 2008

AbstractThis article presents the effects of the die geometry on the expansion ratio of extruded polystyrene foams blown with CO2. Three groups of interchangeable filamentary dies were used to represent the die parameters. The experimental results reveal that a strong relationship exists between the expansion ratio of the extruded polystyrene foams and the die geometry through its effects on the pressure‐drop rate, the die pressure, the amount of premature cell growth, and the initial shape of the extrudate. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Raman spectroscopy for spinline crystallinity measurements. II. Validation of fundamental fiber‐spinning models
Authors: Patel Rajen M. , Doufas Antonios K. , Paradkar Rajesh P. 
Published: May 2008

AbstractThe original Doufas–McHugh two‐phase microstructural/constitutive model for stress‐induced crystallization is expanded to polyolefin systems and validated for its predictive capability of online Raman crystallinity and spinline tension data for two Dow homopolymer polypropylene resins. The material parameters—inputs to the model—are obtained from laboratory‐scale material characterization data, that is, oscillatory dynamic shear, rheotens (melt extensional rheology), and differential scanning calorimetry data. The same set of two stress‐induced crystallization material/molecular parameters are capable of predicting the crystallinity profiles along the spinline and fiber tension very well overall for a variety of industrial fabrication conditions. The model is capable of predicting the freeze point, which is shown, for the first time, to correlate very well with the measured stick point (i.e., the point in the spinline at which the fiber bundle converts from a solid‐like state to a liquid‐like state and sticks to a solid object such as a glass rod). The model quantitatively captures the effects of the take‐up speed, throughput, and melt flow rate on the crystallization rate of polypropylene due to stress‐induced crystallization effects. This validated modeling approach has been used to guide fiber spinning for rapid product development. The original Doufas–McHugh stress‐induced crystallization model is shown to be numerically robust for the simulation of steady polypropylene melt spinning over a wide range of processing conditions without issues of discontinuities due to the onset of the two‐phase constitutive formulation downstream of the die face, at which crystallization more realistically begins. Because of the capturing of the physics of polypropylene fiber spinning and the very good model predictive power, the approximations of the original Doufas–McHugh model are asserted to be reasonable. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Raman spectroscopy for spinline crystallinity measurements. I. Experimental studies
Authors: Paradkar Rajesh P. , Patel Rajen M. , Knickerbocker Ed , Doufas Antonios 
Published: May 2008

AbstractOnline Raman spectra, obtained at different points along the spinline during the melt spinning of polypropylene homopolymer (hPP) fibers, are presented. The percentage crystallinity corresponding to each spectrum was determined from the normalized intensity of the 809‐cm−1 Raman band. A calibration curve for propylene crystallinity was established offline with compression‐molded films and fibers spun under different processing conditions. Several hPPs and propylene–ethylene copolymers (with 5–15% ethylene) were used to cover a wide calibration range for propylene crystallinity (9.5–60.9%) with an R2 value of 0.989. This calibration curve was subsequently used to predict the polypropylene crystallinity in the spinline as a function of distance from the spinneret. Under identical conditions of quench and throughput, at a fixed point along the spinline, the overall crystallinity developed in the fiber was found to increase with an increase in the spinning speed. As the spinning speed increased, the point of the onset of crystallization moved closer to the spinneret. The rise in crystallinity was more gradual, at 750 m/min as opposed to 1500 m/min. Increasing the throughput at constant spinning speed was found to decrease the rate of crystallization because of a decrease in the spinline stress. At a fixed distance from the spinneret under identical conditions of quench and spinning speed, fibers spun at a higher throughput showed less overall crystallinity. The onset and rate of crystallization was found to be faster in the lower melt index H502‐25RG resin as compared to the 5D49 resin under the spinning conditions explored. The experimental data presented here were used to validate fundamental fiber‐spinning models (see part II of this series of articles). The validated models and experimental observations can be used to guide the fiber spinning of isotactic polypropylene for rapid product development. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis and characterization of rubber‐seed‐oil‐based polyurethanes
Authors: Bakare Isiaka O. , Pavithran C. , Okieimen Felix E. , Pillai C. K. S. 
Published: May 2008

AbstractNovel biobased polyurethanes were synthesized from rubber seed oil (RSO), a renewable resource. The RSO monoglyceride, together with xylene and hexamethylene diisocyanate (HMDI), was employed to synthesize the desired urethane‐based prepolymer with isocyanate (NCO)‐terminated end groups followed by curing. The degrees of crosslinking of the polyurethane after curing were assessed with their swelling behavior. The properties of the resulting polyurethanes were found to be dependent on the type of diisocyanate and their molar ratios to the RSO monoglyceride. The network structures, which were assessed through swelling studies, showed that networks based on HMDI with an NCO/OH ratio of 1.50 were better crosslinked than with those toluene diisocyanate. The thermal properties of the samples analyzed by thermogravimetric analysis showed two and three decomposition stages in aliphatic‐ and aromatic‐based RSO polyurethanes, respectively. The highest stability with initial decomposition temperature (253°C) and percentage residual at 500°C (11.4%) was achieved with an aliphatic‐based RSO polyurethane. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Radiation‐induced crosslinking and mechanical properties of blends of poly(lactic acid) and poly(butylene terephthalate‐co‐adipate)
Authors: Sarath Kumara P. H. , Nagasawa Naotsugu , Yagi Toshiaki , Tamada Masao 
Published: May 2008

AbstractBlends of poly(L‐lactic acid) (PLLA) and poly (butylene terephthalate‐co‐adipate) (PBTA) were prepared at ratios of 50 : 50, 60 : 40, and 80 : 20 by melt blending in a Laboplastomill. Improved mechanical properties were observed in PLLA when it was blended with PBTA, a biodegradable flexible polymer. Irradiation of these blends with an electron beam (EB) in the presence of triallyl isocyanurate (TAIC), a polyfunctional monomer, did not cause any significant improvement in the mechanical properties, although the gel fraction increased with the TAIC level and dose level. Irradiation of the blends without TAIC led to a reduction in the elongation at break (Eb) but did not show a significant effect on the tensile strength. Eb of PBTA was unaffected by EB radiation in the absence of TAIC. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis and properties of novel poly(benzimidazopyrrolone amide)s containing pyridine moieties
Authors: Wang Xiaolong , Li Yanfeng , Gong Chenliang , Ma Tao , Zhang Shujiang 
Published: May 2008

AbstractA series of new poly(benzimidazopyrrolone amide) (PPA) copolymers were synthesized by a two‐step procedure, which was the solution polycondensation of a novel pyridine‐containing tetraamine with various aromatic dianhydrides at a room temperature and cyclization of the resulting prepolymers at a high temperature, respectively. The resulting prepolymers from the solution polycondensation, that is, poly(amide amino acid)s (PAAAs), had inherent viscosities of 0.82–0.91 dL/g; then, tough and flexible PPA films could be successfully prepared by the casting of the PAAA solutions onto a glass substrate followed by thermal curing with a program temperature procedure up to 350°C. The obtained PPA films exhibited not only excellent thermal properties with onset decomposition temperatures in the range 502–521°C, glass‐transition temperatures in the range 299–337°C, and residual weight retentions at 700°C in air of 29.1–34.8% but also good mechanical properties with tensile strengths of 102.1–115.9 MPa and elongations at break of 6.8–7.4%. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis and properties of chitosan‐modified poly(acrylic acid)
Authors: Chuang Chung‐Yang , Don Trong‐Ming , Chiu Wen‐Yen 
Published: May 2008

AbstractPotassium persulfate (K2S2O8) was used to initiate the polymerization of acrylic acid (AA) monomer in a chitosan (CS) solution. Both a poly(acrylic acid) (PAA) homopolymer and a CS‐co‐PAA copolymer were produced. When the amount of AA was increased from 5 to 40 g with 5 g of CS, the total monomer conversion was found to increase from 89 to 98% after 2 h of reaction at 70°C. In addition, the percentage of reacted AA monomer being converted to the CS‐co‐PAA copolymer (copolymerization efficiency) and the weight composition of the PAA portion in the copolymer (copolymer composition) both increased with the amount of AA added. The structures and properties of the synthesized CS‐modified PAA polymers were studied. In Fourier transform infrared spectra, the formation of a polyelectrolyte complex between CS chains and PAA chains could be observed. From the thermograms obtained via differential scanning calorimetry, we found that the presence of rigid CS chains increased the glass‐transition temperature of PAA. Thermogravimetric analysis revealed three stages of degradation of the synthesized CS‐modified PAA polymers. The swelling ratio of the CS‐modified PAA polymers depended on the pH value and had a maximum value in a buffer solution at pH 7. This was due to the changes in the morphological structure with the pH value. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
High‐frequency welding of thermoplastic LLDPE/PA 6/PE‐g‐MAH ternary blends
Authors: Yoon C. S. , Lee E. M. , Jang M. S. , Song C. K. , Kang C. Y. , Kim K. H. , Kim B. K. 
Published: May 2008

AbstractHigh frequency (HF) welding of linear low density polyethylene (LLDPE) melt blends with polyamide 6 (PA6) was done at 27.12 MHz using maleic anhydride grafted polyethylene (PE‐g‐MAH) as compatibilizer. HF welding was not possible for the blends at room temperature, but possible at higher temperatures (50, 80°C) although the maximum relaxation frequency was lower than the operating frequency. Greater dielectric constant, dissipation factor, and welding performance were obtained when PA 6 was premixed with PE‐g‐MAH rather than the one‐shot process where all the components were mixed simultaneously. This was interpreted in terms of lowered viscosity of PA 6 phase, which encapsulates the flow effectively and provides great skin effect. Also, the peeling force of resin–resin was greater than resin–nylon mesh due to the higher melting temperature and vacancy of nylon mesh. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Characterization of polyvinyl alcohol/gelatin blend hydrogel films for biomedical applications
Authors: Pawde S. M. , Deshmukh Kalim 
Published: May 2008

AbstractIn the present investigation, attempt was made to prepare blend hydrogel by esterification of polyvinyl alcohol with gelatin. The blend hydrogel was further converted into films by the conventional solution‐casting method. These films were characterized by FTIR, DSC, and X‐ray diffraction studies. The refractive index and viscosity of different composition of the blends were measured in the solution phase of the material. The mechanical properties of the blend films were measured by tensile test. Swelling behavior of the blend hydrogel was also studied. The FTIR spectrum of the blend film indicated complete esterification of the free carboxylic group of gelatin. The DSC results indicate that the addition of gelatin with PVA changes the thermal behavior like melting temperature of PVA, which may be due to the miscibility of PVA with gelatin. The interaction of gelatin with PVA molecule changes the crystallite parameters and the degree of crystallinity. The crystallinity of the blend film was mainly due to gelatin. The comparison of viscosity indicated an increase in the segment density within the molecular coil. The results revealed the changes observed in the properties of the gel, and it enhances the gel formation at viscoelastic phase of the material. The blend film had sufficient strength and water‐holding capacity. The results obtained indicated that the blend film could be used for various biomedical applications such as wound dressing and drug‐delivery systems. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008