bluuebunny/crossref_metadata_2025 huggingface dataset:
Breath volatile organic compounds for chronic kidney disease progression monitoring
Authors: Li Lei , Wang Jue , Feng Fei , Yan Jiayi , Zhao Bin , Li Xinxin , Zhong Yifei
Published: November 2023

A breath volatile organic compound (VOC) combination whose components all increase with chronic kidney disease (CKD) progression is superior to any single component for monitoring CKD progression.
Chemical synthesis of complex oxide thin films and freestanding membranes
Authors: Salles Pol , Machado Pamela , Yu Pengmei , Coll Mariona
Published: November 2023

Oxides offer unique physical and chemical properties that inspire rapid advances in materials chemistry to design and nanoengineer materials compositions and implement them in devices for a myriad of applications.
Role of electron and hole doping in the NdNi1−xVxO3 nanostructure
Authors: Basu Raktima , Kumawat Reshma , Sahu Mrinmay , Miah Abu Bakkar , Mitra Partha , Mukherjee Goutam Dev
Published: November 2023

Switching the majority charge carriers and variations in the electronic properties in nanostructured NdNiO3 by hole and electron injection without any structural transition.
In situ growth of copper-based energetic complexes on GO and an MXene to synergistically promote the thermal decomposition of ammonium perchlorate
Authors: Li Shuting , Li Min , Han Jinxi , Xia Zhengqiang , Chen Sanping , Xie Gang , Gao Shengli , Lu Jack Y. , Yang Qi
Published: November 2023

In situ growth of copper-based energetic complexes on the surface of carbon materials (GO and an MXene) can effectively promote the thermal decomposition of ammonium perchlorate.
Comparative techno-economic and life-cycle analysis of precious versus non-precious metal electrocatalysts: the case of PEM fuel cell cathodes
Authors: Pedersen Angus , Pandya Jinil , Leonzio Grazia , Serov Alexey , Bernardi Andrea , Stephens Ifan E. L. , Titirici Maria-Magdalena , Petit Camille , Chachuat Benoît
Published: November 2023

Fe–N–C catalyst production outperforms Pt/C from an enviro-economic viewpoint, but further Fe–N–C activity development is required before deployment in PEMFCs.
Synthesis of biodegradable PGA-PBC-PGA triblock copolymers and closed-loop recycling via a thermal depolymerization strategy
Authors: Wang Yong , Wen Liang , Liu Jiajian , Li Chuncheng , Zhang Zijian , Xiao Yaonan , Yin Tian , Wu Shaohua , Jiang Zhikui , Zhang Bo
Published: November 2023

This work provides a strategy for synthesizing PGA-PBC-PGA triblock copolymers and allows for the recovery of GL within 3.0 h through depolymerization in an 82% yield.
Efficient polyethylene terephthalate biodegradation by an engineered Ideonella sakaiensis PETase with a fixed substrate-binding W156 residue
Authors: Yin Qingdian , Zhang Jiaxing , Ma Sen , Gu Tao , Wang Mengfan , You Shengping , Ye Sheng , Su Rongxin , Wang Yaxin , Qi Wei
Published: November 2023

The S92P/D157A variant of Ideonella sakaiensis PETase (IsPETase) showed significantly enhanced thermostability and PET degradation activity. The W156 residue of the variant was fixed in the substrate-binding conformation.
Improving quantitative analysis of cement elements in laser-induced breakdown spectroscopy through combining matrix matching with regression
Authors: Zhang Chenwei , Song Weiran , Hou Zongyu , Wang Zhe
Published: November 2023

LIBS shows potential for analyzing cement. However, there are issues with matrix effects when using LIBS for cement analysis. This study proposes a matrix-matching quantitative analysis method to decrease the impact of matrix effects.
Enhancing thermoelectric performance of single-walled carbon nanotube/reduced graphene oxide composites with small organic molecules as a novel additive
Authors: Jang Jae Gyu , Kim Tae-hoon , Kim Sung Hyun , Hong Jong-In
Published: November 2023

Intercalating 1 into a composite of single-walled carbon nanotubes (SWCNTs) and reduced graphene oxides achieved a ZT over 6.8 × 10−3, 2.3 times higher than SWCNTs (2.9 × 10−3), by improving Seebeck coefficient and reducing thermal conductivity.
Composite structure of a-MoSX@Ni9S8/NF nanoflower rods for efficient HER under a thermal field
Authors: Jiang Xiaohao , Xiao Rongtao , Wang Honggui , Zhang Ya
Published: November 2023

The a-MoSX@Ni9S8/NF was prepared by NF sulfidation followed by electrochemical deposition. With the assistance of a thermal field, the interfacial charge transfer efficiency can be increased, resulting in an improvement of HER performance of the a-MoSX@Ni9S8/NF.
Correction: A facile, one-pot reductive alkylation of aromatic and heteroaromatic amines in aqueous micellar media: a chemoenzymatic approach
Authors: Ganesh Krithika , Sambasivam Ganesh , Sivashanmugam Karthikeyan
Published: November 2023

Correction for ‘A facile, one-pot reductive alkylation of aromatic and heteroaromatic amines in aqueous micellar media: a chemoenzymatic approach’ by Krithika Ganesh et al., Org. Biomol. Chem., 2023, 21, 4264–4268, https://doi.org/10.1039/D3OB00386H.
Impulsively generated waves in two-fluid plasma in the solar chromosphere: Heating and generation of plasma outflows
Authors: Kumar M. , Murawski K. , Kadowaki L. , Kuźma B. , Kilpua E. K. J.
Published: November 2023

Context. We present new insights into impulsively generated Alfvén and magneto-acoustic waves in the partially ionized two-fluid plasma of the solar atmosphere and their contribution to chromospheric heating and plasma outflows.

Aims. Our study attempts to elucidate the mechanisms responsible for chromospheric heating and excitation of plasma outflows that may contribute to the generation of the solar wind in the upper atmospheric layers. The main aim of this work is to investigate the impulsively generated waves by taking into account two-fluid effects. These effects may alter the wave propagation leading to attenuation and collisional plasma heating.

Methods. The two-fluid equations were solved by the JOint ANalytical Numerical Approach (JOANNA) code in a 2.5-dimensional (2.5D) framework to simulate the dynamics of the solar atmosphere. Here, electrons + ions (protons) and neutrals (hydrogen atoms) are treated as separate fluids, which are coupled via ion-neutral collisions. The latter acts as a dissipation mechanism for the energy carried by the waves in two-fluid plasma and may ultimately lead to the frictional heating of the partially ionized plasma. The waves in two-fluid plasma, which are launched from the top of the photosphere, are excited by perturbations induced by localized Gaussian pulses in the horizontal components of the ion and neutral velocities.

Results. In the middle and upper chromosphere, a substantial fraction of the energy carried by large amplitude waves in the two-fluid plasma is dissipated in ion-neutral collisions, resulting in the thermalization of wave energy and generation of plasma outflows. We find that coupled Alfvén and magneto-acoustic waves are more effective in heating the chromosphere than magneto-acoustic waves.

Conclusions. Large-amplitude waves in the two-fluid plasma may be responsible for heating the chromosphere. The net flow of ions is directed outward, leading to plasma outflows in the lower solar corona, which may contribute to the solar wind at higher altitudes The primary source of wave energy dissipation in the current paradigm comes from collisions between ions and neutrals.
Dissociation processes of ionized freons: CHFCl2+ and CF2Cl2+ in the gas phase
Authors: Petersen Allan Christian , Sølling Theis Ivan
Published: November 2023

The present study reveals the effects of symmetry on how the distribution and flow of energy play out on the decomposition of small halocarbons. Unimolecular decay of the freons CHFCl2 and CF2Cl2 when ionized has been investigated. Mass spectrometric results that encompass isotope effects (peak heights) and energy distribution in the exit channel (peak shapes) are interpreted by computational methods. Non-statistical processes of electronic predissociation and isolated state decay are shown to be directly associated with molecular symmetry.
Regulating ferroelectricity in Hf0.5Zr0.5O2 thin films: Exploring the combined impact of oxygen vacancy and electrode stresses
Authors: Bai Mingkai , Hong Peizhen , Han Runhao , Chai Junshuai , Zhang Bao , Hou Jingwen , Xiong Wenjuan , Yang Shuai , Gao Jianfeng , Luo Feng , Huo Zongliang
Published: November 2023

Hf0.5Zr0.5O2 (HZO) is a promising candidate for low-power non-volatile memory due to its nanoscale ferroelectricity and compatibility with silicon-based technologies. Stress and oxygen vacancy (VO) are key factors that impact the ferroelectricity of HZO. However, their combined effects have not been extensively studied. In this study, we investigated the impact of the VO content on HZO thin films’ ferroelectricity under different electrode stresses by using TiN and tungsten (W) top electrodes and controlling ozone dose time during HZO deposition. The HZO thin films with W top electrodes exhibit elevated stress levels and a greater abundance of orthorhombic/tetragonal phases, and the HZO thin films with TiN top electrode shows an increase in the monoclinic phase with increasing ozone dose time. The residual polarization (Pr) of the capacitors with TiN and W top electrodes displayed different or even opposing trends with increasing ozone dose time, and the VO content decreases with increasing ozone dose time for both sets of capacitor samples. We propose a model to explain these observations, considering the combined influence of electrode stresses and VO on the free and formation energy of the crystalline phase. Increasing the VO content promotes the transformation of the tetragonal phase to the orthorhombic phase in HZO films with TiN top electrodes, and with W top electrodes, a higher VO content prevents the tetragonal phase from transforming into the orthorhombic/monoclinic phase. Additionally, an alternative explanation is proposed solely from the perspective of stress. These findings provide valuable insights into the regulation of ferroelectricity in HZO thin films.
From energy racism to people’s power: unpacking the electricity crisis and resistance in Orange Farm, Johannesburg
Authors: Sinwell Luke , Ngwane Trevor , Maggott Terri
Published: November 2023

Energy racism, a brainchild of racial capitalism, systemically excludes the black majority who are denied safe, reliable and clean household energy. It manifests in violent and, sometimes, deadly ways, which are often met with organised resistance from below. Drawing on a case study of Orange Farm, Johannesburg, this article explores the politics of popular resistance to the crisis of neoliberalism and cost recovery. It argues that the macro-sphere of energy production (for example, global coal consumption and Eskom) and the micro-sphere of consumption and resistance intersect within the constraints of a racialised system of capital extraction.
Exploring Cognitive Functioning among Forensic Mental Health Inpatients
Authors: Cronje Han-Mari , Nixon Margaret , Rossell Susan L.
Published: November 2023

A large proportion of forensic mental health (FMH) inpatients experience cognitive impairments, which may impact the extent to which they benefit from interventions aimed at reducing their risk of recidivism. These impairments should be identified and responded to as quickly and accurately as possible. The current study explored when and how FMH inpatients’ cognition is assessed during their stay at a forensic hospital, with a cognitive profile being constructed of the sample. The medical files of inpatients who resided at the hospital in Melbourne (Australia) during January 2016 and December 2019 were reviewed retrospectively. A total of 99 medical files were identified. The type, timing and results of each cognitive assessment were collected. Frequency analysis revealed more than half of the sample received a cognitive assessment, with most of the cognitive assessments being conducted within the first year of an inpatient’s admission to hospital. Between 19% and 31% of inpatients with available cognitive data demonstrated a global cognitive impairment, depending on the cognitive measure being used. These results highlight the value of assessing FMH inpatients for cognitive impairments to respond to them appropriately to increase their chances of rehabilitation. Careful consideration should be given to the type of cognitive assessment tool used among this demographic.
Ammonia cracking for hydrogen production using a microwave argon plasma jet
Authors: Zhang Xinhua , Cha Min Suk
Published: November 2023

Ammonia (NH3) is a promising hydrogen carrier that effectively connects producers of blue hydrogen with consumers, giving rapid conversion of ammonia to hydrogen a critical role in utilizing hydrogen at the endpoints of application in an ammonia-hydrogen economy. Because conventional thermal cracking of NH3 is an energy intensive process, requiring a relatively longer cold start duration, plasma technology is being considered as an assisting tool—or an alternative. Here we detail how an NH3 cracking process, using a microwave plasma jet (MWPJ) under atmospheric pressure, was governed by thermal decomposition reactions. We found that a delivered MW energy density (ED) captured the conversion of NH3 well, showing a full conversion for ED > 6 kJ l−1 with 0.5-% v/v NH3 in an argon flow. The hydrogen production rate displayed a linear increase with MW power and the NH3 content, being almost independent of a total flow rate. A simplified one-dimensional numerical model, adopting a thermal NH3 decomposition mechanism, predicted the experimental data well, indicating the importance of thermal decomposition in the plasma chemistry. We believe that such a prompt thermal reaction, caused by MW plasma, will facilitate a mobile and/or non-steady application. A process combined with the conventional catalytic method should also effectively solve a cold start issue.
Temperature dependence of growth-sector-dependent Raman spectra of boron-doped diamonds synthesized at high-pressure high-temperature
Authors: Nikolenko A S , Strelchuk V V , Danylenko I M , Starik S P , Kovalenko T V , Lysakovskyi V V , Ivakhnenko S O
Published: November 2023

Single crystals of boron-doped diamond (BDD) were synthesized by the temperature gradient method in high-pressure and high-temperature conditions in the Fe–Al–B–C system, and multisectoral diamond plates were extracted. Temperature-dependent (77–600 K) high-resolution Raman spectroscopic studies have been carried out to investigate the behavior of anharmonic phonon decay in the {001}, {113}, and {111} growth sectors of multisectoral diamond plates with different content of boron impurities (⩽80 ppm) and compare with the data for undoped IIa diamond. Micro-Fourier transform infrared spectroscopy was used to estimate the spatial distribution of uncompensated boron impurity [Na-Nd] in BDD plates by analyzing boron-related absorption peaks. The plates were shown to have non-uniform growth-sector-dependent content of uncompensated boron impurity in the range from 1.1 × 1018 to 1.4 × 1019 cm−3. The effects of anharmonic decay (damping) of optical phonons in BDD are studied by modeling the temperature dependence of phonon frequency and linewidth of the diamond’s F2g and boron-induced vibrational modes. The extrapolated zero-temperature optical phonon linewidth and frequency and the anharmonic nature of their linear relationship are determined as a function of the growth sector and boron doping. The predominant mechanisms and parameters of the anharmonic decay of optical phonons are determined, which is of fundamental importance for the thermal conductivity of semiconductor materials. The anharmonic phonon decay remained the predominant process at higher temperatures, irrespective of the doping level.
DEC-NWD: an approach for open set domain adaptation in fault diagnosis
Authors: Zhao Xiaoping , Peng Peng , Xue Xingan , Ma Mengyao
Published: November 2023

The issue of data-driven cross-domain fault diagnosis for rolling bearings has been effectively addressed through advancements in domain adaptation (DA) methods. However, most existing approaches assume the same set of labels for training data and test data. This assumption often falls short of reality, as new fault types may emerge during the testing phase, resulting in less effective DA methods based on marginal distribution. To address this issue, this study proposes an open set DA method based on domain similarity, entropy, confidence, and nuclear-norm 1-Wasserstein discrepancy (NWD). Within this method, a sample-level transferability criterion is introduced. This criterion quantifies the transferability of target samples and assigns small weights to the unknown class. The complementary nature of entropy and confidence is exploited to improve the discriminability of the network for highly uncertain predictions and to use multiple classifiers to compensate for the possible influence of prediction errors on confidence. Additionally, the NWD is utilized in this method. It treats the classifier as a discriminator and leverages the predicted discriminative information to maximize the alignment of the common classes between the source and target domains. The proposed method has been validated through extensive experiments conducted on two publicly available bearing datasets.
A maximum cyclic impulses energy ratio deconvolution fused with enhanced envelope derivative operator frequency spectrum for early fault diagnosis of rolling bearing
Authors: Zheng Kai , Tang Jiaquan , Shi Yang , Tan Feng , Bai Yin , Wen Siguo
Published: November 2023

Blind deconvolution is a powerful tool for rolling bearing fault diagnosis. As one of deconvolution methods, maximum second-order cyclostationarity blind deconvolution (CYCBD) is proved to be effective in extracting bearing fault characteristics. However, the performance of CYCBD method is greatly compromised by setting of fault characteristic frequency (FCF) in advance. Moreover, its performance decreases dramatically under the interference of random shocks and strong noise. To address these issues, a new deconvolution method, named as maximum cyclic impulses energy ratio deconvolution (MCIERD) fused with enhanced envelope derivative operator frequency spectrum (EEDOFS) is proposed in this research. In this method, the EEDOFS is proposed to estimate the FCF. Furthermore, the cyclic impulses energy ratio (CIER) is employed as the deconvolution indicator. Moreover, the hybrid firefly and particle swarm optimization algorithm is used to solve the optimal filter coefficients by maximizing the CIER. Simulation results show that EEDOFS exhibits a greater robustness in estimating FCF accurately under strong interferences and MCIERD performs well in extracting fault cyclic impulses under the interference of heavy noise and random shocks. Finally, three run-to-failure bearing datasets are employed for experimental validation, whose results demonstrate the effectiveness of EEDOFS in accurate estimating FCF and identifying the early bearing fault. Meanwhile, MCIERD fused with EEDOFS is proved to have greater advantages in extracting early bearing fault feature.
Three-dimensional hybrid fusion networks for current-based bearing fault diagnosis
Authors: Huang Xufeng , Xie Tingli , Hu Jiexiang , Zhou Qi
Published: November 2023

Intelligent fault diagnosis (IFD) techniques commonly use vibration-based measurements to perform health monitoring of critical rotating components in industrial systems. However, these vibration-based approaches may be limited in cost-sensitive applications, because the installation of vibration sensors is inconvenient and vibration sensors are expensive. Considering the difficulties of IFD using only current-related information from the motor current signal (MCS), this paper proposes a three-dimensional hybrid-fusion neural network (3D-HFN) that can automatically perform both data- and feature-level fusion of multi-phase current signals for MCS-based IFD of the rolling bearing. The 3D-HFN consists of the multivariate variational mode decomposition (MVMD) and an improved three-dimensional convolution neural network (3D-CNN). Firstly, MVMD is proposed to process multi-phase current signals, which adaptively acquire several intrinsic mode functions with mode-alignment properties. Subsequently, signal-to-image conversion and 3D stacking methods are used to construct 3D-like data in the current-phase dimension, which can fully preserve the interaction relationship between different phases using data-level fusion. Finally, an improved 3D-CNN with multiscale feature fusion and the smooth maximum unit is proposed to learn the 3D-like data and identify different health conditions for the rolling bearing. An open-source dataset with composite bearing faults is used to validate the merits of the proposed method. Experimental results show that the proposed approach has achieved more reliable diagnosis performance than other hand-crafted or 2D/3D-CNN-based algorithms in MCS-based IFD of the rolling bearing.
Dispersive hydrodynamics in non-Hermitian nonlinear Schrödinger equation with complex external potential
Authors: Chandramouli Sathyanarayanan , Ossi Nicholas , Musslimani Ziad H , Makris Konstantinos G
Published: November 2023

In this paper dispersive hydrodynamics associated with the non-Hermitian nonlinear Schrödinger (NLS) equation with generic complex external potential is studied. In particular, a set of dispersive hydrodynamic equations are obtained. They differ from their classical counterparts (without an external potential), by the presence of additional source terms that alter the density and momentum equations. When restricted to a class of Wadati-type complex potentials, the resulting hydrodynamic system conserves a modified momentum and admits constant intensity/density solutions. This motivates the construction and study of an initial value problem (IVP) comprised of a centred (or non-centred) step-like initial condition that connects two constant intensity/density states. Interestingly, this IVP is shown to be related to a Riemann problem posed for the hydrodynamic system in an appropriate traveling reference frame. The study of such IVPs allows one to interpret the underlying non-Hermitian Riemann problem in terms of an ‘optical flow’ over an obstacle. A broad class of non-Hermitian potentials that lead to modulationally stable constant intensity states are identified. They are subsequently used to numerically solve the associated Riemann problem for various initial conditions. Due to the lack of translation symmetry, the resulting long-time dynamics show a dependence on the location of the step relative to the potential. This is in sharp contrast to the NLS case without potential, where the dynamics are independent of the step location. This fact leads to the formation of diverse nonlinear wave patterns that are otherwise absent. In particular, various gain-loss generated near-field features are present, which in turn drive the optical flow in the far-field which could be comprised of various rich nonlinear wave structures, including DSW-DSW, DSW-rarefaction, and soliton-DSW interactions.
Experiences of working time intensification and extensification: examining the influence of logics of production in IT work
Authors: Howcroft Debra , Taylor Phil
Published: November 2023

This article examines the intensification and extensification of working time among IT workers. As standardised hours have become increasingly eroded, understanding the nuanced experience of re-configured working time becomes vital. Informed by conceptual distinctions between clock time, process time and tertiary time, this study investigates how working time is constituted among, and experienced by, two distinct IT occupational categories: support workers and mobile apps developers. Theorising experiences of working time with recourse to distinct logics of production, which encompass and reflect labour markets, new technology product markets and occupational communities, illuminates how working time experiences are shaped. This facilitates an explanation of the underlying dynamics that surround the interaction between the three concepts of time, which advances our understanding of intensification and extensification.
A radiation of Psylliodes flea beetles on Brassicaceae is associated with the evolution of specific detoxification enzymes
Authors: Gikonyo Matilda W , Ahn Seung-Joon , Biondi Maurizio , Fritzlar Frank , Okamura Yu , Vogel Heiko , Köllner Tobias G , Şen İsmail , Hernández-Teixidor David , Lee Chi-Feng , Letsch Harald , Beran Franziska
Published: November 2023

Flea beetles of the genus Psylliodes have evolved specialized interactions with plant species belonging to several distantly related families, mainly Brassicaceae, Solanaceae, and Fagaceae. This diverse host use indicates that Psylliodes flea beetles are able to cope with different chemical defense metabolites, including glucosinolates, the characteristic defense metabolites of Brassicaceae. Here we investigated the evolution of host use and the emergence of a glucosinolate-specific detoxification mechanism in Psylliodes flea beetles. In phylogenetic analyses, Psylliodes species clustered into four major clades, three of which contained mainly species specialized on either Brassicaceae, Solanaceae, or Fagaceae. Most members of the fourth clade have broader host use, including Brassicaceae and Poaceae as major host plant families. Ancestral state reconstructions suggest that Psylliodes flea beetles were initially associated with Brassicaceae and then either shifted to Solanaceae or Fagaceae, or expanded their host repertoire to Poaceae. Despite a putative ancestral association with Brassicaceae, we found evidence that the evolution of glucosinolate-specific detoxification enzymes coincides with the radiation of Psylliodes on Brassicaceae, suggesting that these are not required for using Brassicaceae as hosts but could improve the efficiency of host use by specialized Psylliodes species.
Towards optimization of ceftazidime dosing in obese ICU patients: the end of the ‘one-size-fits-all’ approach?
Authors: Correia Patricia , Launay Manon , Balluet Rémi , Gergele Laurent , Gauthier Vincent , Morel Jérome , Beuret Pascal , Mariat Christophe , Thiery Guillaume , Perinel Ragey Sophie
Published: November 2023

Background

Ceftazidime is commonly used as a key antibiotic against Pseudomonas aeruginosa in critically ill patients. ICU patients have severely altered and variable antibiotic pharmacokinetics, resulting in lower antimicrobial concentrations and potentially poor outcome. Several factors, including obesity and renal function, may influence pharmacokinetics. Thus, the objective of the study was to evaluate the impact of obesity and renal function on ceftazidime plasma concentrations and dosing regimen in ICU patients.

Methods

All consecutive adult patients from six ICUs, treated with continuous ceftazidime infusion and under therapeutic drug monitoring evaluation, were included. Obesity was defined as BMI ≥30 kg/m². Glomerular filtration rate (GFR) was estimated by the Chronic Kidney Disease Epidemiology Collaboration formula. The ceftazidime recommended target for plasma concentrations was between 35 and 80 mg/L.

Results

A total of 98 patients (45 obese), with an average weight of 90 (±25) kg, were included. Mean GFR was 84.1 (±40.4) mL/min/1.73 m2. Recommended ceftazidime plasma concentrations were achieved for only 48.0% of patients, with median dosing regimen of 6 g/day. Obese patients had lower ceftazidime plasma concentrations compared with non-obese patients (37.8 versus 56.3 mg/L; P = 0.0042) despite similar dosing regimens (5.83 g/day versus 5.52 g/day, P = 0.2529). Almost all augmented renal clearance patients were underdosed despite ceftazidime dosing of 6.6 (±0.8) g/day. Weight-based ceftazidime dosing seemed to attenuate such obesity-related discrepancies, regardless of GFR.

Conclusions

Obese ICU patients required significantly greater ceftazidime doses to achieve the target range. A tailored dosing regimen may be considered based on weight and GFR. Future prospective studies should be performed to confirm this individualized dosing approach.
Professional education for public health in the United States
Authors: Fee Elizabeth , Rosenkrantz Barbara
Published: November 2023

The federal structure of the United States has meant that the public health function is divided among a multitude of state, city, and local health departments, with a relatively weak centralized authority. The most important federal organization in public health is the United States Public Health Service, an agency that has often aided the development of state health departments by lending expert personnel and providing advice and consultation on specific problems. The proper balance of responsibility for public health among federal, state, and local health departments has been a rather contentious question; taking the long view, it has shifted in the course of the twentieth century in the direction of greater federal responsibility for research, regulation, and financing of public health activities.
The British Diploma in Public Health: heyday and decline
Authors: Acheson Roy
Published: November 2023

By 1900, the struggles and confusion which had been characteristic of the early years of the Diploma in Public Health had been resolved. In the halcyon days which followed throughout the reign of Edward VII the number of candidates successfully attempting the DPH more than doubled. In this chapter we shall see how by the onset of the First World War new difficulties had developed. These were in the management of the examination itself, in the adaptation of the syllabus to the changing needs of the practical world for which it was designed and in its appropriateness for doctors working elsewhere in the British Empire.
Engineering and mathematical aspects of functional stimulation (peripheral and spinal cord)
Authors: Vodovnik Lojze , Stefanovska Aneta
Published: November 2023

The term functional electrical stimulation (FES) is used at present for a large variety of procedures. Each of these procedures has its own clinical, engineering, and mathematical aspects and therefore we propose a classification of functional stimulation in order to discuss the proper mathematical tools which are relevant for each of the categories.
Patterned electrical stimulation
Authors: Kidd G L
Published: November 2023

Functional stimulation will be taken as a form of electrical stimulation that will cause a skeletal muscle to generate a force adequate to perform an artificial function expected of it. An alternative electrical stimulation can be devised which has a different purpose: training or conditioning a skeletal muscle. It would then be able to tolerate and respond to episodes of functional electrical stimulation, or indeed to volitional controls, and generate adequate force for a suitable period of time to perform the artificial or natural function.
Clinical practice of functional electrical stimulation
Authors: Dimitrijevic Meta M , Dimitrijevic Milan R
Published: November 2023

It is not surprising that physicians taking care of paralysed spinal cord injured (SCI) patients and their colleagues, biomedical engineers and clinical neurophysiologists, have known for more than 30 years that muscles paralysed because of upper motor neuron dysfunction are an available source of force and movement when motor unit excitability is controlled by externally applied lower motor neuron stimulation (Liberson et al. 1961; Reswick 1973). This seemingly rather simple approach has developed into a large new field of experimental and clinical research in several countries around the world with research groups that integrate the expertise of physicians, biomedical engineers, physiologists, and other neuroscientists. Researchers involved in this programme in Europe, Australia, Japan, the USA, and other parts of the world are attempting to learn how to improve impaired motor control by means of the external control of the paralysed muscles of wheelchair-bound or ambulatory patients with impaired gait due to trauma of the nervous system or neurological disease.
Spinal cord stimulation
Authors: Illis L S
Published: November 2023

Central functional stimulation (spinal cord stimulation), far from being a pragmatic technique, embodies an increasing amount of scientific theory based on clinical observation, physiological measurement and experiment, and mathematical concepts.
Level and State Densities
Authors: Gadioli E , Hodgson P E
Published: November 2023

In the statistical model of nuclear reactions, discussed in the next chapter, the basic hypothesis is made of the formation of a fully equilibrated compound nucleus whose decay is independent of the mode of formation and entirely governed by the phase space available to the reaction products (Weisskopf and Ewing 1940). A similar hypothesis, the equiprobability of all decay modes of the excited intermediate (projectile + target) composite system, was made by Griffin (1966) in developing the exciton model for pre-equilibrium reactions, and was thereafter adopted in all subsequent theories, including the recent quantum mechanical ones.
Compound Nucleus Reactions
Authors: Gadioli E , Hodgson P E
Published: November 2023

The foundations of the theory of compound nucleus reactions were laid by Bohr (1936) and Bohr and Kalckar (1937). They proposed that a nuclear reaction begins with the capture of the projectile by the target nucleus followed by the sharing of its energy among all the nucleons of the compound system. The compound nucleus lives long enough for complete statistical equilibrium to be established. Subsequently, long after the capture of the projectile, particles are emitted by a statistical process similar to the evaporation of molecules from a liquid drop, until finally the residual nucleus reaches its ground state by gamma emission.
Phenomenological Models Of Pre-Equilibrium Reactions
Authors: Gadioli E , Hodgson P E
Published: November 2023

As mentioned in the Introduction, since 1947 the accumulation of experimental data has indicated the existence of reaction mechanisms intermediate in character between the one-step direct processes which involve few degrees of freedom and the compound nucleus reactions in which the projectile energy is divided between all the nucleons of the compound nucleus in a completely statistical way. For simplicity, all these intermediate processes will be called pre-compound or pre-equilibrium reactions.
Pre-Equilibrium Phenomena In Reactions Induced By Composite Particles And Heavy Ions
Authors: Gadioli E , Hodgson P E
Published: November 2023

The study of pre-equilibrium processes in reactions initiated by complex particles is more difficult, compared with nucleon-induced reactions, owing to the presence of processes competing with complete fusion followed by pre-equilibrium and eventually evaporation. The break-up of the projectile in the nuclear field has been found to contribute noticeably to the total cross-section, at incidence energies as low as about 10 MeV/nucleon. Other interaction mechanisms include, especially in the case of tightly bound particles such as alpha-particles, inelastic and deep-inelastic scattering followed by decay of the excited residual nucleus, few-nucleon transfer processes followed by break-up and/or decay of the projectile-like and target-like fragments, and projectile fragmentation following interaction with nucleons or clusters of nucleons in the target. In the case of heavy ions one is far from having a complete and comprehensive understanding of the variety of interaction processes that may occur between the projectile and the target.
In search of calcium sensitizer compounds; from subcellular models of muscle to in vivo positive inotropic action
Authors: Strauss John D , Rüegg Caspar J , Inge Lues
Published: November 2023

There are a number of pathological conditions in which cardiac performance is insufficient to maintain normal circulatory demands. In such cases, the clinician, or perhaps more to the point, the patient, requires an effective pharmacological tool for improving cardiac performance so that normal function can be restored. The development of ‘calcium sensitizing’ drugs has been pursued to obtain a cardiotonic agent which increases cardiac contractility at the most basic level, that is, at the level of the calcium sensitivity of the myofilaments.
The influence of pH. phosphate, and ionic strength on contraction in skinned cardiac muscle
Authors: Kenfish Jonathan C , Palmer Sue
Published: November 2023

There are two principal ways in which the relationship between Ca+ concentration ([Ca +]) and myofibrillar force development can be measured. The first is to introduce Ca+ -sensitive photoproteins or dyes into the cell and to measure force and cytosolic [Ca +] while both change, for example during the twitch. The second method is to permeabilize (‘skin’) the cell surface membrane so that externally applied ions (Ca2+, MgATP-, and so on) readily diffuse into the cells and so control the myofibrillar environment.
The effects of acidosis on intact cardiac muscle
Authors: Orchard C H , Allen D G , Boyett M R , Elliott A C , Kirby M S
Published: November 2023

It has been known for over 100 years that acidosis decreases the force developed by cardiac muscle when it contracts. Although many of the mechanisms that deliver Ca2+ to the cytoplasm on excitation are inhibited by acidosis,2-4 direct measurements of intracellular [Ca2-] ([Ca2+]i) have shown that the [Ca2+]i transient that initiates contraction actually becomes larger during acidosis.
Modulation of activation of cardiac myofilaments by beta-adrenergic agonists
Authors: Solaro R John
Published: November 2023

The aim of this chapter is to present evidence regarding mechanisms by which beta-adrenergic agonists influence contractility of the heart through modula tion of the control of myofilamcnt activation by Ca + and cross-bridges. The first part of the chapter deals with the molecular processes (Fig. 7.1) by which Ca+ triggers activation of the myofilaments and how the cross-bridge-thin filament reaction itself may determine the state of activation. It is shown that activation involves release of the thin filaments from a prevailing inhibited state.
Myosin light chain phosphorylation and myosin isoenzyme expression regulate cardiac calcium sensitivity by modulation of cross-bridge cycling kinetics
Authors: Morano Ingo
Published: November 2023

The cardiac cell may modulate its force of contraction using two different mechanisms, shown schematically in Fig. 8.1. First, the force of contraction can be increased or decreased by raising or decreasing the myoplasmic free Ca2+ concentration ([Ca2+]i) This mechanism may be designated as [Ca2+]; amplitude modulation.
The genetic engineering and physiology of troponin C: molecular aspects of the modulation of cardiac calcium sensitivity
Authors: Gulati Jagdish , Babu Árvind , Cheng Rendi , Su Hong
Published: November 2023

Activation of the contractile system in the heart is initiated by the increase in Ca concentration in the myoplasm following an action potential. The Ca2+ ions bind to troponin C and switch ‘on’ the thin filaments to permit cross bridge interaction. Tn this chapter this Ca2+ -troponin C reaction is described and a molecular understanding of the switching mechanism is sought. Special attention 1s devoted to recent approaches combining molecular genetics and physiology for studying the structure-function correlations of troponin C.
Effects of anoxia and ischaemia on cardiac muscle
Authors: Allen D G , Lee J A , Elliott A C
Published: November 2023

The deleterious effects of ischaemia on myocardial function have been recognized since the earliest studies on living hearts. For instance, Harvey in 1628 was aware that coronary circulation was required for cardiac function and Chirac (1698) described how the heart of a dog ceased to beat after a coronary artery had been ligated. Obstruction of a coronary artery in a large mammal has remained a favourite model for the study of myocardial ischaemia, and the classic study by Tennant and Wiggers in 1935 showed how the ischaemic region became flaccid and demonstrated systolic bulging within a minute of ligation.
Clinical experience with calcium sensitizers in congestive heart failure
Authors: Holubarsch Christian , Hasenfuss Gerd
Published: November 2023

In the treatment of congestive heart failure, three general pharmacological principles are used nowadays: (l) vasodilation to decrease myocardial afterload and increase stroke volume; (2) diuretics to control salt and water balance; and (3) positive inotropism to increase myocardial force generation and thereby stroke volume. The only positive inotropic compound which has been used successfully and frequently is digitalis, although long-term treatment with digitalis-like substances has been questioned for two different reasons. Firstly, digitalis may lead to arrhythmogcnic side effects. Secondly, the therapeutic range of digitalis is very narrow.
Future directions
Authors: Lee John A , Allen David G
Published: November 2023

It will be apparent from previous chapters that considerable progress has been made m our understanding of cardiac contractile mechanisms. Until recently most attention focused on alterations of force produced via changes in the cytosolic calcium transient, but it is now clear that alteration of myofilament calcium responsiveness is an important independent mechanism affecting cardiac force production in many physiological and pathophysiological situations. Of particular interest has been the finding that much of the reduction of developed force occurring in hypoxia and ischacmia can be accounted for by reduced calcium responsiveness of the contractile protcins.
Atomic Forces
Authors: Born Max , Huang Kun
Published: November 2023

Crystalline solids are distinguished from other states of matter by a periodic arrangement of the atoms; such a structure is called a crystal lattice. A precise description of the geometry of a lattice will be given later in § 22 of Chapter V. Essentially the regularity displayed by a crystal lattice is that of a three-dimensional mesh which divides space into identical parallelepipeds. Imagine a number of identical atoms placed at the intersections of such a mesh; then we have what is known as a Bimple lattice (or Bravais lattice). The interstitial parallelepipeds, which have atoms for corners, are referred to as the elementary lattice cells; in a simple lattice there is thus exactly one atom to each elementary cell. Now if the atoms are replaced by similarly oriented molecules, the result is a general lattice structure; clearly every cell contains as many atoms as there are in one molecule. The term molecule here describes the geometrical dispositions of the atoms and need not signify a real molecule (a group of atoms form a real molecule in a lattice only if they are more tightly bound to one another than to other atoms in the lattice).
The Claudian Invasion
Authors: Salway Peter
Published: November 2023

While it is not really true that the Romans acquired their empire in a series of fits of absent-mindedness, much of it came as the incidental result of wars whose causes were very varied, or of the absorption of foreign peoples in other ways, including the bequest of kingdoms in the wills of their rulers or involvement in nominating princes to their thrones. It has been doubted whether Roman emperors can be said to have had ‘policies’ in the modern sense, due to the enormous burden of daily response to immediate problems that fell on them personally. Certainly, within particular reigns or periods, emperors and their advisers did sometimes attempt specific objectives. However, much more important than policy were the trends that consistently underlay Roman action, which were remarkably persistent through the centuries. Some we have already seen. Others need identifying before we can understand much of what Rome and individual Romans did or did not do.
Recovery and Advance
Authors: Salway Peter
Published: November 2023

A picture is now beginning to emerge of the progress of material Romanization and the development of Roman institutions immediately after the pacification of the province. In due course archaeology may tell us more about how quickly the cities struck down by the rebels recovered, and about the manner in which other towns developed in this period. Structural evidence for new public buildings comes from London and Bath. In London a building detected under the first phase of the forum may date from this period. It seems to have been of civil type, in contrast to the buildings of military appearance that Boudicca destroyed on the site which may have housed the governor’s administration before the great rebellion. At Bath, some time in the fifteen years after the rebellion, a start was made on the grand complex of baths and temple, in which a deliberate attempt seems to have been made to do spectacular honour to a native cult by amalgamating it publicly with one of the greatest Roman deities in the new worship of Sulis Minerva, rather than to obliterate or downgrade the British element.
Hadrianic Britain
Authors: Salway Peter
Published: November 2023

The death of Trajan in n7 marks a turning-point m Roman, indeed European, history. In Britain Trajan’s reign had been a period of military withdrawal and consolidation, in sharp contrast to his expansion of the empire elsewhere. In Dacia and Mesopotamia his campaigns won whole new regions, and that alone is enough to explain why no forward policy was adopted in Britain. In many ways, Trajanic Britain foreshadows the general imperial strategy of Hadrian, who gave up the expansionist policy and abandoned Trajan’s new territories in the east. In the military sphere, Hadrian concentrated on restoring order in the various parts of the empire where there was disaffection, and in consolidating the frontiers. A great part of his reign was spent in personal tours of inspection in the provinces. The renewed respect for the Principate that had been won by Nerva and Trajan permitted the new emperor to direct his energies away from Roman politics and towards the largest schemes of civil and military reconstruction. His constant presence among the frontier armies encouraged their loyalty. His keen interest in the provinces underlined the fact that he was the second provincial to come to the throne (from the same city as Trajan), and emphasized the oneness of the empire-or at least of its communities of Roman citizens, wherever they might be located within its territories. Italy was no longer to be regarded as mistress of the Roman world, with the provinces as her inferiors, and, though she always retained a special social status, she gradually lost her political privileges.
The Antonine Frontier
Authors: Salway Peter
Published: November 2023

In 136, two years before his death, Hadrian had prepared for the succession by adopting one of the consuls for that year, Lucius Ceionius Commodus, under the name of L. Aelius Caesar. However, the latter’s own premature death forced a new choice on the emperor. This time he settled upon the man whom we know as Antoninus Pius, a distinguished member of the senate who had acquired a reputation for honesty and devotion to duty. He had been a consular since 120, and towards the end of Hadrian’s reign he became a member of the emperor’s consilium, the advisory committee that was analogous to the group of senior friends on whom Roman magistrates relied for counsel. Hadrian had made the consilium principis more formal than before, and there can be no doubt that Antoninus’ long career in the public service, and his closeness to the emperor towards the end, gave him intimate knowledge of the workings of the empire and of Hadrian’s own policies in matters of state. In the emperor’s last year Antoninus had largely administered the empire on Hadrian’s behalf He thus came to the throne exceptionally well prepared. To extend the principle of adoptive succession further, Hadrian had also required Antonomous to adopt both Marcus