Non-Debye Behavior of the Néel and Brown Relaxation in Interacting Magnetic Nanoparticle Ensembles.

We used ac-susceptibility measurements to study the superspin relaxation in FeO/Isopar M nanomagnetic fluids of different concentrations. Temperature-resolved data collected at different frequencies, χ″ vs. T|, reveal magnetic events both below and above the freezing point of the carrier fluid (T = 197 K): χ″ shows peaks at temperatures T and T around 75 K and 225 K, respectively.

Evidence of Individual Superspin Relaxation in Diluted FeO/Hexane Ferrofluids.

We used dc magnetization and ac susceptibility to investigate the magnetic relaxation of ferrofluids made of 8 nm average-diameter FeO nanoparticles dispersed in hexane. Samples of different concentrations (δ) spanning two orders of magnitude ranging from 0.66 to 0.

Stability of Superprotonic CsHPO Hermetically Sealed in Different Environments.

Using powder X-ray diffraction and AC impedance spectroscopy, we have found that the superprotonic CsHPO (CDP) phase is stable at T = 250 °C when sealed in different volumes (15 mL and 50 mL) of dry air or inert gasses. Under these conditions, CDP's proton conductivity stays constant at 2.5 × 10 S·cm for at least 10 h.

Efficient electrocatalytic hydrogen gas evolution by a cobalt-porphyrin-based crystalline polymer.

Herein, we report a crystalline CoTcPP-based [TcPP = the anion of meso-tetra(4-carboxyphenyl)porphyrin] polymeric system, 1, as a hydrogen evolution reaction (HER) electrocatalyst in acidic aqueous media. The material was characterized by powder X-ray diffraction (p-XRD), Fourier transform infrared (FT-IR) spectroscopy, and energy dispersive X-ray (EDX) analysis and its morphology was probed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Polymer 1 shows a surface area of 441.

Ac-susceptibility investigations of superspin blocking and freezing in interacting magnetic nanoparticle ensembles.

We have investigated the effect of dipolar interactions on the superspin blocking and freezing of 9 nm average size Fe3O4 magnetic nanoparticle ensembles. Our dynamic susceptibility data reveals a two-regime behavior of the blocking temperature, T(B), upon diluting a Fe3O4/hexane magnetic fluid. As the nanoparticle volume ratio, Φ, is reduced from an as-prepared reference Φ = 1 to Φ = 1/96, the blocking temperature decreases from 46.

Evidence of superspin-glass behavior in Zn0.5Ni0.5Fe2O4 nanoparticles.

We have used dc-magnetization and ac-susceptibility to investigate the superspin dynamics in 9 nm average size Zn(0.5)Ni(0.5)Fe(2)O(4) magnetic particles at temperatures (T) between 3 and 300 K.

A genomics approach to identify susceptibilities of breast cancer cells to "fever-range" hyperthermia.

Background: Preclinical and clinical studies have shown for decades that tumor cells demonstrate significantly enhanced sensitivity to "fever range" hyperthermia (increasing the intratumoral temperature to 42-45°C) than normal cells, although it is unknown why cancer cells exhibit this distinctive susceptibility.

Methods: To address this issue, mammary epithelial cells and three malignant breast cancer lines were subjected to hyperthermic shock and microarray, bioinformatics, and network analysis of the global transcription changes was subsequently performed.

Results: Bioinformatics analysis differentiated the gene expression patterns that distinguish the heat shock response of normal cells from malignant breast cancer cells, revealing that the gene expression profiles of mammary epithelial cells are completely distinct from malignant breast cancer lines following this treatment.

Exposure studies of core-shell Fe/Fe(3)O(4) and Cu/CuO NPs to lettuce (Lactuca sativa) plants: Are they a potential physiological and nutritional hazard?

Iron and copper nanomaterials are widely used in environmental remediation and agriculture. However, their effects on physiological parameters and nutritional quality of terrestrial plants such as lettuce (Lactuca sativa) are still unknown. In this research, 18-day-old hydroponically grown lettuce seedlings were treated for 15 days with core-shell nanoscale materials (Fe/Fe(3)O(4), Cu/CuO) at 10 and 20mg/L, and FeSO(4)·7H(2)O and CuSO(4)·5H(2)O at 10mg/L.

Sorption kinetic study of selenite and selenate onto a high and low pressure aged iron oxide nanomaterial.

The sorption of selenite (SeO(3)(2-)) and selenate (SeO(4)(2-)) onto Fe(3)O(4) nanomaterials produced by non microwave-assisted or microwave-assisted synthetic techniques was investigated through use of the batch technique. The phase of both synthetic nanomaterials was determined to be magnetite by X-ray diffraction. The average grain sizes of non microwave-assisted and microwave-assisted synthetic Fe(3)O(4) were determined to be 27 and 25 nm, respectively through use of the Scherrer's equation.

Evidence of low-temperature superparamagnetism in Mn3O4 nanoparticle ensembles.

Using ac-susceptibility, dc-magnetization, and transmission electron microscopy, we have investigated the magnetic behavior of Mn(3)O(4) nanoparticle ensembles at temperatures below the paramagnetic-to-ferrimagnetic transition of the title material (T(N) approximately equal 41 K). Our data show no evidence of the complex magnetic ordering exhibited by bulk Mn(3)O(4), or of a magnetic behavior around T(N) that has a dynamic (relaxation) origin. Instead, we find a low-temperature (at approximately 11 K) magnetic anomaly that manifests itself as a peak in the out-of-phase component of the ac-susceptibility.

Evidence of the differential biotransformation and genotoxicity of ZnO and CeO2 nanoparticles on soybean (Glycine max) plants.

Concern and interest related to the effects of nanomaterials on living organisms are growing in both the scientific and public communities. Reports have described the toxicity of nanoparticles (NPs) on micro- and macro-organisms, including some plant species. Nevertheless, to the authors' knowledge there are no reports on the biotransformation of NPs by edible terrestrial plants.

Microwave Assisted Synthesis of Iron(III) Oxyhydroxides/Oxides Characterized Using Transmission Electron Microscopy, X-ray Diffraction, and X-ray Absorption Spectroscopy.

Microwave assisted synthesis of iron oxide/oxyhydroxide nanophases was conducted using iron(III) chloride titrated with sodium hydroxide at seven different temperatures from 100 degrees C to 250 degrees C with pulsed microwaves. From the XRD results, it was determined that there were two different phases synthesized during the reactions which were temperature dependent. At the lower temperatures, 100 degrees C and 125 degrees C, it was determined that an iron oxyhydroxide chloride was synthesized.

Dynamic susceptibility evidence of surface spin freezing in ultrafine NiFe2O4 nanoparticles.

We investigated the dynamic behavior of ultrafine NiFe2O4 nanoparticles (average size D = 3.5 nm) that exhibit anomalous low temperature magnetic properties such as low saturation magnetization and high-field irreversibility in both M(H) and ZFC-FC processes. Besides the expected blocking of the superspin, observed at T1 approximately 45 K, the system undergoes a magnetic transition at T2 approximately 6 K.

High-temperature crystal structures and chemical modifications in RbH(2)PO(4).

We have used laboratory and synchrotron x-ray diffraction to investigate the structural and chemical changes undergone by polycrystalline RbH(2)PO(4) upon heating within the 30-250 °C temperature interval. Our data show no evidence of the previously reported onset of partial polymerization at T = 96 °C (Park et al 2001 J. Phys.

On the possibility of using polycrystalline material in the development of structure-based generic assays.

The discovery of ligands that bind specifically to a targeted protein benefits from the development of generic assays for high-throughput screening of a library of chemicals. Protein powder diffraction (PPD) has been proposed as a potential method for use as a structure-based assay for high-throughput screening applications. Building on this effort, powder samples of bound/unbound states of soluble hen-egg white lysozyme precipitated with sodium chloride were compared.

[Clinical and epidemiological profile of hepatitis B and C virus infection: a 34 soldier hospitalized in a military hospital retrospective study].

Unlabelled: The hepatitis B and C virus infection is a public health problem due to the evolution of the disease and the quality of life of the patients, and the costs involved of the therapy and health care services.

Aim: To asses the clinical and epidemiological profile of the 34 militaries hospitalized in a military hospital, infected with these viruses.

Material And Method: The main method of not being ill is to respect the common measures of prevention.

[Treatment of aseptic ulnar non-union in a patient with spastic hemiparesis by Ilizarov method].

Both-bone diaphyseal forearm fractures in children are common lesions. Non-union is very rare, almost exclusively in the ulna. We present a case of forearm fracture in a patient with spastic hemiparesis involving the injured forearm, treated initially with open reduction and intramedullary nailing.

[Hospital admissions for digestive diseases: 1995-2003 morbidity in a military hospital].

Digestive diseases are still currently one of the leading causes of illness. The study was conducted of those individuals admitted to hospital during the 1995-2003 period, whose main diagnosis at admission to hospital had been encoded according to the International Disease Classification as a digestive disease. The highest rate of admissions was in civilian males (the military hospital assures health care services for militaries and their families), due to duodenal ulcer and liver diseases.

High-temperature phase transitions in CsH2PO4 under ambient and high-pressure conditions: a synchrotron x-ray diffraction study.

To clarify the microscopic origin of the temperature-induced three-order-of-magnitude jump in the proton conductivity of CsH(2)PO(4) (superprotonic behavior), we have investigated its crystal structure modifications within the 25-300 degrees C temperature range under both ambient- and high-pressure conditions using synchrotron x-ray diffraction. Our high-pressure data show no indication of the thermal decomposition/polymerization at the crystal surface recently proposed as the origin of the enhanced proton conductivity [Phys. Rev.

Phase separation and size effects in Pr(0.70)Ba(0.30)MnO(3+δ) perovskite manganites.

The crystal structure and magnetotransport properties of the A-site ionic ordered state in Pr(0.70)Ba(0.30)MnO(3+δ) (δ = 0, 0.

[Prioritization of the main health problems having impact upon the activity of the Emergency Military Hospital "Dr. Iacob Cihac" of Iaşi in the years 1995-2003].

The various health problems that are faced by a hospital institution at any given point in time, compete for the usually limited resources that are available, while the health needs are infinite.Therefore, the prioritization process is a key to a functional activity. The prioritization method involves the formal selection criteria and system used to prioritize the health conditions.

[Some aspects regarding the activity analysis of a military hospital].

Providing secondary health care for military staff and related personnel, Clinical Emergency Military Hospital "Dr. Iacob Cihac" it is the biggest hospital among those having the same profile. There are many factors with influence upon hospital's activities.

[The results of the Sommerville-Petit procedure in the treatment of the typical congenital hip dislocation].

The studied group from the Pediatric Surgery and Orthopedics Clinic, Iaşi, consisted of 87 cases, which means that a total of 118 hips were treated between September 1998-September 2004. In 116 cases, the extension was performed with trans-femoral Kirschner wire, in a period of 3-7 weeks. After 7-14 days of extension, the authors performed adductor and sometimes psoas tenotomy.

Characterization and crystal structure of D-mannitol hemihydrate.

The objectives of this study were (i) to isolate and characterize mannitol hydrate, and (ii) to solve its crystal structure from high-resolution synchrotron X-ray powder diffraction data. Mannitol hydrate was prepared by freeze-drying aqueous mannitol solutions (5% w/v) under controlled conditions. X-ray powder diffractometry, differential scanning calorimetry, and thermogravimetric analyses indicated that mannitol exists as a hemihydrate (C(6)H(14)O(6) .

Complications following gastric tube esophagoplasty in children.

Surgery in children with caustic esophageal burns, esophageal atresia or other esophageal disorders can be performed using gastric tube esophagoplasty. Between 1991 and 1999, a number of 41 such procedures have been performed in our department, using the original technique developed by Gavriliu. The results were assessed as good and very good in 83% of the cases, and fair or bad in the rest of 17%.