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Autor polazi od činjenice kako je za govor o svećeničkom celibatu i o smislu njegove obvezatnosti u Katoličkoj crkvi potrebno, barem pokušati, odgovoriti na neka temeljna pitanja: je li celibat čisto crkvena, kanonsko-pravna, disciplinska odredba koja se pojavila u jednom povijesnom trenutku ili je njezin izvor i izvorište negdje drugdje i/ili Netko drugi? Koja su to (ne)opravdanja na temelju kojih Učiteljstvo i danas, usprkos svim izazovima i problemima s kojima se Crkva u promijeni epohe suočava, ’uporno’ od svojih ministerijalnih službenika traži potpunu i trajnu uzdržljivost radi kraljevstva Božjeg iako je teološki posve jasno da celibat nije konstitutivni element svetog reda? Analizirajući koncilsku i postkoncilsku doktrinu, svećenički celibat svoj izvor pronalazi u trima različitim područjima: u daru Duha Svetog – karizmi, u slobodnom odgovoru kandidata koji u ljubavi preuzima evanđeoski savjet preko javnog obećanja u trenutku primanja svetog reda đakonata i na posljetku u kan. 277 Zakonika kanonskoga prava, odnosno u kanonsko-pravnoj institucionalizaciji povezanoj s teološkom, duhovnom i pastoralnom prikladnosti koju Crkva, vođena Duhom Svetim, stavlja između celibata i svetog reda, i koju taj isti Duh podupire u izvršavanju. Dakle, riječ je ponajprije o moralnoj obvezi koja se odnosi na teološki poredak s obzirom da proizlazi iz posebnog odnosa između Boga koji zove i osobe koja se odaziva, a tek posljedično taj se odnos ’ratificira’ u kanonsko-pravnoj, disciplinskoj obvezi, koja sa sobom donosi različitost prava ali i obveza. Crkva i danas celibat vidi kao svojevrsni crkveni miraz ili povlasticu, ne apsolutnu i ne nepromjenljivu, već mudro promišljenu, pozitivno priznatu, povijesno akreditiranu i, usprkos svim izazovima, iskustveno još uvijek kredibilnu. Od velike je važnosti ne odvajati celibat od drugih evanđeoskih savjeta (siromaštva i poslušnosti), kreposti i dimenzija svećeničkog života. Sve te dimenzije moraju biti u konstantnom dijalogu, ne zaboravlj, The author begins by stating the fact that the discourse on priestly celibacy and on the sense of its obligatoriness in the Catholic Church needs to at least try to answer some fundamental questions: Is celibacy a mere ecclesiastical, canonical-legal, disciplinary directive that was introduced in a given historical moment, or is its source something else or Someone else? What are the (non-) justifications on the basis of which the Magisterium continues »to insist« even today, despite all challenges and problems that the Church faces at the turn of the epoch, on the complete abstinence of her ministerial officials for the Kingdom of God, although it is theologically entirely clear that celibacy is not a constitutive element of the holy orders? According to the conciliar and postconciliar doctrine, the priestly celibacy has its source in three different areas: in the gift of the Holy Spirit – charisma, in the free and loving response of a candidate who takes upon himself the Gospel counsel through the act of public promise in the moment of receiving the holy order of deacon, and, finally, in the can. 277 of the Code of Canon Law, i.e., in canonical-legal institutionalisation related to the theological, spiritual, and pastoral appropriateness that the Church, led by the Holy Spirit, sees between celibacy and the holy orders, and which is also supported by that same Spirit in its execution. Therefore, celibacy concerns primarily the moral obligation that is established by the theological order, insofar as its source is the special relation between God who calls and the person who responds, and only secondarily is that relation »ratified« in the canonical-legal, disciplinary obligation that carries its own rights and duties. The Church continues to see celibacy as a kind of ecclesiastical dowry or privilege that is not absolute or unchangeable, but nevertheless wisely instituted, positively recognised, historically accredited, and, despite all challenges, experientially

2020 The Authors Biochar-based compound fertilizers (BCF) and amendments have proven to enhance crop yields and modify soil properties (pH, nutrients, organic matter, structure etc.) and are now in commercial production in China. While there is a good understanding of the changes in soil properties following biochar addition, the interactions within the rhizosphere remain largely unstudied, with benefits to yield observed beyond the changes in soil properties alone. We investigated the rhizosphere interactions following the addition of an activated wheat straw BCF at an application rates of 0.25% (g·g−1 soil), which could potentially explain the increase of plant biomass (by 67%), herbage N (by 40%) and P (by 46%) uptake in the rice plants grown in the BCF-treated soil, compared to the rice plants grown in the soil with conventional fertilizer alone. Examination of the roots revealed that micron and submicron-sized biochar were embedded in the plaque layer. BCF increased soil Eh by 85 mV and increased the potential difference between the rhizosphere soil and the root membrane by 65 mV. This increased potential difference lowered the free energy required for root nutrient accumulation, potentially explaining greater plant nutrient content and biomass. We also demonstrate an increased abundance of plant-growth promoting bacteria and fungi in the rhizosphere. We suggest that the redox properties of the biochar cause major changes in electron status of rhizosphere soils that drive the observed agronomic benefits.

The low-energy lattice dynamics of the quasiperiodic spin-ladder cuprate Sr14-xCaxCu24O41 are investigated using terahertz frequency synchrotron radiation. A high density of low-lying optical excitations is present in the 1-3 THz energy range, while at least two highly absorbing excitations stemming from long-wavelength acoustic oscillations of the incommensurate chain and ladder sublattices, are observed at subterahertz frequencies. The effects of Ca substitution on the subterahertz quasiacoustic sliding mode gaps is investigated using coherent synchrotron radiation. Analysis of the results suggest increasing substitution of Sr for Ca is accompanied by a transfer of spectral weight between sliding modes associated with different chain-ladder dynamics. The observation is consistent with a transfer of hole charges from the chains to the ladders and modification of the sublattice dimensions following Ca substitution. The results are discussed in context to the significance of low-lying vibrational dynamics and electron-phonon coupling in the superconducting state of certain quasiperiodic systems.

The terahertz absorption spectra of aspirin and benzoic acid have been measured in the range 200-500 cm-1 (6-15 THz). Density-functional theory (DFT) modeling has assigned fundamental vibrational modes to the observed absorption bands. Hydrogen bonds between the crystalline planes of aspirin resulted in better agreement between the experimental and modeled spectra than for benzoic acid. The similar structure of these two molecules suggests a similar absorption spectrum, which indeed was obtained experimentally. However, the detailed crystal structure and molecular differences result in some of the apparently common absorption bands being assigned to different vibrational modes through the DFT modeling. Thus, our study importantly reveals that even though crystalline forms of two similar molecules may have similar experimental terahertz spectra, the resemblance may be superficial rather than fundamental.

THz transmission spectra of the commonly used pain killers-aspirin and paracetamol were measured using the FTIR technique and calculated using the density functional theory method. Despite the shift in the frequencies, there are common absorption bands between these compounds. The common bands were established to be primarily due to the various movements of the benzene ring.

Nanobiotechnology is an immensely potential invention, which is expected to bring about revolutionary changes in many aspects of essential human needs including medical treatments and foods. Although the technology has passed through its embryonic stage, its medical applications in preparing and delivering drugs to target cells of human bodies to cure incurable diseases are still under scientific scrutiny. A 2007 study suggests that Australia needs to have a review of its regulatory framework for nanotechnology by 2017. This article examines the current regulation of nanotechnology and its medical applications in Australia, and observes that it would be premature to impose any stringent regulation at this stage on medical experimentations. We are of the view that an excessively precautionary policy may hinder further research, which is critical to discovering the benefit and harm with certainty. Hence, in the greater interest of the facilitation of research and affirmation of benefits of this technology, we recommend that adopting a hybrid regulatory method composed of self-regulation and accommodating government regulation would be an appropriate policy approach to the regulation of nanobiotechnology. We also accept the need for a set of internationally harmonized policy principles to guide our actions in relation to this technology.

Recent studies have shown that the pyrolysis of biomass combined with clay can result in both lower cost and increase in plant yields. One of the major sources of nutrients for pasture growth, as well as fuel and building materials in Tibet is yak dung. This paper reports on the initial field testing in a pasture setting in Tibet using yak dung, biochar, and attapulgite clay/yak dung biochars produced at ratios of 10/90 and 50/50 clay to dung. We found that the treatment with attapulgite clay/yak dung (50/50) biochar resulted in the highest pasture yields and grass nutrition quality. We also measured the properties and yields of mixtures of clay/yak dung biochar used in the field trials produced at 400 °C and 500 °C to help determine a possible optimum final pyrolysis temperature and dung/clay ratio. It was observed that increasing clay content increased carbon stability, overall biochar yield, pore size, carboxyl and ketone/aldehyde functional groups, hematite and ferrous/ferric sulphate/thiosulphate concentration, surface area and magnetic moment. Decreasing clay content resulted in higher pH, CEC, N content and an enhanced ability to accept and donate electrons. The resulting properties were a complex function of both processing temperature and the percentage of clay for the biochars processed at both 400 °C and 500 °C. It is possible that the increase in yield and nutrient uptake in the field trial is related to the higher concentration of C/O functional groups, higher surface area and pore volume and higher content of Fe/O/S nanoparticles of multiple oxidation state in the 50/50 clay/dung. These properties have been found to significantly increase the abundance of beneficial microorganisms and hence improve the nutrient cycling and availability in soil. Further field trials are required to determine the optimum pyrolysis production conditions and application rate on the abundance of beneficial microorganisms, yields and nutrient quality.

Biochars have been recognized as an important material to improve soil properties. In a number of studies their beneficial properties have been found to increase with residence time in soil and during the composting process. The beneficial properties have been correlated with surface functional groups resulting from the interactions between char particles, inorganic and organic matter in the soil and soil biota. These interactions result in the formation of organo-mineral phases on the internal and external surfaces of the biochar. A paucity of information exists, particularly from longer-term field trials, on organo-mineral phases present on both the internal and external surfaces of the biochar. To characterize the structure of, and interface between, the carbon and mineral phases, we examined biochars recovered from two field trials and after composting from different countries using high resolution scanning electron microscopy (SEM), atomic resolution transmission electron microscopy (TEM) and scanning TEM (STEM), energy electron loss spectroscopy (EELS) and energy dispersive X-ray spectroscopy (EDS) at resolutions of 1-20 nm. The work revealed the formation of porous agglomerates of different minerals/inorganic compounds bound together with organic compounds on the surfaces of the biochar. In some cases, these agglomerates were bound together to form organo-mineral associations. The analyses also showed that the organic compounds containing both N and C functional groups and mixed valence iron oxide nanoparticles are possibly interacting with the organic compounds. The analysis also showed the formation of pores at the interface of the carbon matrix and organo-mineral aggregates.

Poster presentation - We investigate carbon-based materials (graphite, graphite nanofibers and multi-walled carbon nanotubes) using terahertz time-domain spectroscopy (THz-TDS). The THz-TDS of carbon-based materials has been especially useful for understanding of many fundamental physical properties (e.g. the electronic structure and electron-phonon interactions, etc.) of all sp2 carbons, given that carbon-based materials can be either semiconducting or metallic depending on their geometric structures. A significant difference was obtained in the spectra of graphite nanofibers as compared to the multi-walled carbon nanotubes and graphite.

Dramatic changes in molecular structure, degradation pathway, and porosity of biochar are observed at pyrolysis temperatures ranging from 250 to 550 °C when bamboo biomass is pretreated by iron-sulfate-clay slurries (iron-clay biochar), as compared to untreated bamboo biochar. Electron microscopy analysis of the biochar reveals the infusion of mineral species into the pores of the biochar and the formation of mineral nanostructures. Quantitative 13C nuclear magnetic resonance (NMR) spectroscopy shows that the presence of the iron clay prevents degradation of the cellulosic fraction at pyrolysis temperatures of 250 °C, whereas at higher temperatures (350-550 °C), the clay promotes biomass degradation, resulting in an increase in both the concentrations of condensed aromatic, acidic, and phenolic carbon species. The porosity of the biochar, as measured by NMR cryoporosimetry, is altered by the iron-clay pretreatment. In the presence of the clay, at lower pyrolysis temperatures, the biochar develops a higher pore volume, while at higher temperature, the presence of clay causes a reduction in the biochar pore volume. The most dramatic reduction in pore volume is observed in the kaolinite-infiltrated biochar at 550 °C, which is attributed to the blocking of the mesopores (2-50 nm pore) by the nonporous metakaolinite formed from kaolinite.

Herein we investigate a (001)-oriented GaAs1−xBix/GaAs structure possessing Bi surface droplets capable of catalysing the formation of nanostructures during Bi-rich growth, through the vapourliquid-solid mechanism. Specifically, self-aligned "nanotracks" are found to exist trailing the Bi droplets on the sample surface. Through cross-sectional high-resolution transmission electron microscopy the nanotracks are revealed to in fact be elevated above surface by the formation of a subsurface planar nanowire, a structure initiated mid-way through the molecular-beam-epitaxy growth and embedded into the epilayer, via epitaxial overgrowth. Electron microscopy studies also yield the morphological, structural, and chemical properties of the nanostructures. Through a combination of Bi determination methods the compositional profile of the film is shown to be graded and inhomogeneous. Furthermore, the coherent and pure zincblende phase property of the film is detailed. Optical characterisation of features on the sample surface is carried out using polarised micro-Raman and micro-photoluminescence spectroscopies. The important light producing properties of the surface nanostructures are investigated through pump intensity-dependent micro-PL measurements, whereby relatively large local inhomogeneities are revealed to exist on the epitaxial surface for important optical parameters. We conclude that such surface effects must be considered when designing and fabricating optical devices based on GaAsBi alloys.

Porous structures made up of Fe3O4 nanoparticles were used to adsorb methyl blue in water. Controlled release of the methyl blue to water was then achieved by application of a magnetic field. Application of a pure DC field did not result in any release. Application of a pure AC field caused released of the methyl blue. However, a combination of both DC and AC fields resulted in much faster release. The mechanism by which this operated is believed to result from viscous friction. Nanoparticles are strongly aligned in the DC field and oscillate under the influence of the AC field. This study demonstrates a concept for controlled drug delivery, where pharmaceutical molecules, similar to methyl blue, would be adsorbed onto nanoporous Fe3O4 structure and the released at a target by application of appropriately localised magnetic fields.

A recent application of terahertz spectroscopy is to biochar, the agricultural charcoal produced by pyrolysis of various organic materials. Biochars simultaneously improve soil fertility and assist in carbon sequestration. Terahertz spectroscopy allows different biochars to be distinguished. However, the origin of the absorption features observed has not been clear. Given that biochar-based fertilizers are rich in aromatic compounds, we have investigated simple aromatic compounds as an approach to unravelling the complex biochar spectrum.

In this study we report in-plane nanotracks produced by molecular-beam-epitaxy (MBE) exhibiting lateral self-assembly and unusual periodic and out-of-phase height variations across their growth axes. The nanotracks are synthesized using bismuth segregation on the GaAsBi epitaxial surface, which results in metallic liquid droplets capable of catalyzing GaAsBi nanotrack growth via the vapor-liquid-solid (VLS) mechanism. A detailed examination of the nanotrack morphologies is carried out employing a combination of scanning electron and atomic force microscopy and, based on the findings, a geometric model of nanotrack growth during MBE is developed. Our results indicate diffusion and shadowing effects play significant roles in defining the interesting nanotrack shape. The unique periodicity of our lateral nanotracks originates from a rotating nucleation "hot spot" at the edge of the liquid-solid interface, a feature caused by the relative periodic circling of the non-normal ion beam flux incident on the sample surface, inside the MBE chamber. We point out that such a concept is divergent from current models of crawling mode growth kinetics and conclude that these effects may be utilized in the design and assembly of planar nanostructures with controlled non-monotonous structure

The effects of graphene oxide (GO) addition on the dispersion of nanosilver (Ag) in an MgB2 matrix were studied using bulk samples prepared through a diffusion process. The influence of the dispersion of Ag and Ag/GO particles on the critical current density (Jc) of MgB2 was also investigated. GO has emerged as an excellent dopant which can significantly improve both the low- and high-field performance of MgB2 due to its capability to improve intergrain connectivity (GO) and inter- and intragrain pinning (GO and AgMg). The addition of nanosize Ag particles also results in an improvement of vortex pinning, and at the same time, it offers the advantage of preventing the loss of Mg during the sintering process. It is found that the dispersion of nanosilver in the presence of GO results in significant improvements in the critical current density in MgB2, particularly at high magnetic fields, due to improved intergrain connectivity and flux pinning. The use of the GO net as a platform for doping MgB2 in our case with Ag yielded a 10-fold-better critical current density (Jc) than standard Ag doping at 9 T and 5 K. Even without sophisticated processes, we obtained a Jc result of 104 A/cm2 at 9 T and 5 K, which is one of the best ever achieved.

Terahertz spectroscopy of benzoic acid (BA) and two of its derivatives, 2-hydroxybenzoic acid (2OH-BA) and 3-hydroxybenzoic acid (3OH-BA), has been investigated in the spectral region 200 to 500 cm-1 (6.06 to 15.15 THz). The spectra show distinct absorption features. There is agreement between some of the absorption lines observed for these compounds, despite a shift in energy, which is attributed to the differences in the molecular structures. Numerical modelling gave corresponding absorption lines, and this helped in the assignment. Temperature dependence studies revealed that most of the absorption lines are composite lines in this frequency region.

Previous THz spectroscopy of the TNT explosive precursor, 2,4-dinitrotoluene (DNT), has been restricted to room temperature (apart from one set of data at 11 K). Here, for the first time, we investigate the spectrum as the temperature is systematically varied, from 7 to 245 K. Many new features appear in the spectrum on cooling below room temperature. As well as the five absorption lines observed previously, we observe five additional lines. In addition, a new room-temperature line at 8.52 THz (281 cm−1) is observed. Six of the lines red-shift with temperature and four of them blue-shift. The blue shift is explained by interplay between intramolecular and intermolecular hydrogen bonds. The variation in line width and line intensity with temperature is not systematic, although a conspicuous decrease in line intensity with temperature is observed in all cases. Modeling with hybrid PBE0 and TPSSh functionals helps identify absorption modes.

Liposomal drug delivery systems (LDDSs) are promising tools used for the treatment of diseases where highly toxic pharmacological agents are administered. Currently, destabilising LDDSs by a specific stimulus at a target site remains a major challenge. The bacterial mechanosensitive channel of large conductance (MscL) presents an excellent candidate biomolecule that could be employed as a remotely controlled pore-forming nanovalve for triggered drug release from LDDSs. In this study, we developed superparamagnetic nanoparticles for activation of the MscL nanovalves by magnetic field. Synthesised CoFe2O4 nanoparticles with the radius less than 10 nm were labelled by SH groups for attachment to MscL. Activation of MscL by magnetic field with the nanoparticles attached was examined by the patch clamp technique showing that the number of activated channels under ramp pressure increased upon application of the magnetic field. In addition, we have not observed any cytotoxicity of the nanoparticles in human cultured cells. Our study suggests the possibility of using magnetic nanoparticles as a specific trigger for activation of MscL nanovalves for drug release in LDDSs.

Purpose: Due to the current interest in MRI-guided radiotherapy, the magnetic properties of the materials commonly used in radiotherapy are becoming increasingly important. In this paper, mea- surement results for the magnetization (BH) curves of a range of sintered heavy tungsten alloys used in radiation shielding and collimation are presented. Methods: Sintered heavy tungsten alloys typically contain > 90% tungsten and < 10% of a combina- tion of iron, nickel, and copper binders. Samples of eight different grades of sintered heavy tungsten alloys with varying binder content were investigated. Using a superconducting quantum interference detector magnetometer, the induced magnetic moment m was measured for each sample as a function of applied external field H0and the BH curve derived. Results: The iron content of the alloys was found to play a dominant role, directly influencing the magnetization M and thus the nonlinearity of the BH curve. Generally, the saturation magnetization increased with increasing iron content of the alloy. Furthermore, no measurable magnetization was found for all alloys without iron content, despite containing up to 6% of nickel. For two samples from different manufacturers but with identical quoted nominal elemental composition (95% W, 3.5% Ni, 1.5% Fe), a relative difference in the magnetization of 11%–16% was measured. Conclusions: The measured curves show that the magnetic properties of sintered heavy tungsten alloys strongly depend on the iron content, whereas the addition of nickel in the absence of iron led to no measurable effect. Since a difference in the BH curves for two samples with identical quoted nominal composition from different manufacturers was observed, measuring of the BH curve for each individual batch of heavy tungsten alloys is advisable whenever accurate knowledge of the magnetic properties is crucial. The obtained BH curves can be used in FEM simulations to predict the magnetic impact of sintered heavy tungsten a

We employ a combination of pulsed- and continuous-wave polarized terahertz spectroscopy techniques to probe temperature-dependent spin waves in the antiferromagnet NdFeO3. Our optical data span 1.6-467 K and reveal a conspicuous spin reorientation between 110 and 170 K, during which the lower-energy mode softens completely. Complementary inelastic neutron scattering reveals that the frequencies of the optically excited spin waves are consistent with a temperature-variable spin gap in the low-energy spin-wave dispersion of NdFeO3. The result links the temperature dependence of the spin waves to a dynamic in-plane anisotropy. The magnetic anisotropy is calculated based on the results of the optical measurements. The change observed in the anisotropy energy along the a and c crystal axes suggests that the spin reorientation evident in NdFeO3 is driven by temperature-dependent in-plane anisotropy.