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A range of self‐power technologies is reviewed. Self‐powered systems are defined as those that operate by harnessing ambient energy present within the environment of the system. As MEMS and smart‐material technologies mature, embedded and remote systems become more attractive. Self‐power offers a potential for solving the difficult problem of supplying energy to these devices.

The capability of microparticle/objects patterning in the three-dimensional (3D) printing structure could improve its performance and functionalities. This paper aims to propose and evaluate a novel acoustic manipulation approach.

A novel method to accumulate the microparticles in the cylindrical tube during the 3D printing process is proposed by acoustically exciting the structural vibration of the cylindrical tube at a specific frequency, and subsequently, focusing the 50-μm polystyrene microparticles at the produced pressure node toward the center of the tube by the acoustic radiation force. To realize this solution, a piezoceramic plate was glued to the outside wall of a cylindrical glass tube with a tapered nozzle. The accumulation of microparticles in the tube and printing structure was monitored microscopically and the accumulation time and width were quantitatively evaluated. Furthermore, the application of such technology was also evaluated in the L929 and PC-12 cells suspended in the sodium alginate and gelatin methacryloyl.

The measured location of pressure and the excitation frequency of the cylindrical glass tube (172 kHz) agreed quite well with our numerical simulation (168 kHz). Acoustic excitation could effectively and consistently accumulate the microparticles. It is found that the accumulation time and width of microparticles in the tube increase with the concentration of sodium alginate and microparticles in the ink. As a result, the microparticles are concentrated mostly in the central part of the printing structure. In comparison to the conventional printing strategy, acoustic excitation could significantly reduce the width of accumulated microparticles in the printing structure (p < 0.05). In addition, the possibility of high harmonics (385 and 657 kHz) was also explored. L929 and PC-12 cells suspended in the hydrogel can also be accumulated successfully.

This paper proves that the proposed acoustic approach is able to increase the accuracy of printing capability at a low cost, easy configuration and low power output.

This paper aims to Separation and sorting of biological cells is desirable in many applications for analyzing cell properties, such as disease diagnostics, drugs delivery, chemical processing and therapeutics.

Acoustic energy-based bioparticle separation is a simple, viable, bio-compatible and contact-less technique using, which can separate the bioparticles based on their density and size, with-out labeling the sample particles.

Conventionally available bioparticle separation techniques as fluorescence and immunomagnetic may cause a serious threat to the life of the cells due to various compatibility issues. Moreover, they also require an extra pre-processing labeling step. Contrarily, label-free separation can be considered as an alternative solution to the traditional bio-particle separation methods, due to their simpler operating principles and lower cost constraints. Acoustic based particle separation methods have captured a lot of attention among the other reported label-free particle separation techniques because of the numerous advantages it offers.

This study tries to briefly cover the developments of different acoustic-based particle separation techniques over the years. Unlike the conventional surveys on general bioparticles separation, this study is focused particularly on the acoustic-based particle separation. The study would provide a comprehensive guide for the future researchers especially working in the field of the acoustics, in studying and designing the acoustic-based particle separation techniques.

The study insights a brief theory of different types of acoustic waves and their interaction with the bioparticles is considered, followed by acoustic-based particle separation devices reported till the date. The integration of acoustic-based separation techniques with other methods and with each other is also discussed. Finally, all major aspects like the approach, and productivity, etc., of the adopted acoustic particle separation methods are sketched in this article.

The purpose of this paper is to demonstrate the feasibility of using kinetic energy harvesting to power wireless condition monitoring sensors.

The system presented duty cycles its operation depending upon the energy being harvested. The harvested energy is stored on a supercapacitor and the system samples sufficient vibration data to enable an FFT to be performed at the receiver.

The results of this study show it is perfectly feasible to power practical wireless condition monitoring sensors entirely from the vibrations of the machines being monitored.

Energy harvesting techniques can be used to power wireless sensors in a range of applications. Removing the need for a battery power supply presents obvious environmental benefits and avoids the need to periodically replace batteries.

Various approaches have been made to alter the vibration sensing properties of zinc oxide (ZnO) films to achieve high sensitivity. This paper aims to report the experimental study of the fabrication of precursor molar ratio concentration varied ZnO nanostructures grown on rigid substrates using the refresh hydrothermal method. The effect of these fabricated ZnO nanostructures-based vibration sensors was experimentally investigated using a vibration sensing setup.

ZnO nanostructures have been grown using low temperature assisted refresh hydrothermal method with different precursor molar concentrations 0.025 M (R1), 0.075 M (R2) and 0.125 M (R3). Poly 3,4-ethylenedioxythiophene polystyrene sulfonate, a p-type material is spun coated on the grown ZnO nanostructures. Structural analysis reveals the increased intensity of the (002) plane and better c-axis orientation of the R2 and R3 sample comparatively. Morphological examination shows the changes in the grown nanostructures upon increasing the precursor molar concentration. The optical band gap value decreases from 3.11 eV to 3.08 eV as the precursor molar concentration is increased. Photoconductivity study confirms the formation of a p-n junction with less turn-on voltage for all the fabricated devices. A less internal resistance of 0.37 kΩ was obtained from Nyquist analysis for R2 compared with the other two fabricated samples. Vibration testing experimentation showed an improved output voltage of the R2 sample (2.61 V at 9 Hz resonant frequency and 2.90 V for 1 g acceleration) comparatively. This also gave an increased sensitivity of 4.68 V/g confirming its better performance when compared to the other fabricated two samples.

Photoconductivity study confirms the formation of a p-n junction with less turn-on voltage for all the fabricated devices. A less internal resistance of 0.37 kΩ was calculated from the Nyquist plot. Vibration testing experimentation proves an increased sensitivity of 4.68 V/g confirming its better performance when compared to the other fabricated two samples.

Vibration testing experimentation proves an increased sensitivity of 4.68 V/g for R2 confirming its better performance when compared to the other fabricated two samples.

The purpose of this paper is to provide a contemporary look at the current state‐of‐the‐art in wireless sensor networks (WSNs) for structure health monitoring (SHM) applications and discuss the still‐open research issues in this field and, hence, to make the decision‐making process more effective and direct.

This paper presents a comprehensive review of WSNs for SHM. It also introduces research challenges, opportunities, existing and potential applications. Network architecture and the state‐of‐the‐art wireless sensor communication technologies and standards are explained. Hardware and software of the existing systems are also clarified.

Existing applications and systems are presented along with their advantages and disadvantages. A comparison landscape and open research issues are also presented.

The paper presents a comprehensive and recent review of WSN systems for SHM applications along with open research issues.

Delay in histologically confirming rectal cancer may lead to late treatment as histological confirmation is required prior to chemo-radiotherapy or surgical intervention. Multidisciplinary colorectal meetings indicate that there are patients who require multiple tissue biopsy episodes prior to histologically confirming rectal cancer. The purpose of this paper is to examine a quality improvement (QI) measure’s impact on tissue biopsy process diagnostic yield.

The authors performed the study in two phases (pre- and post-QI), between February 2012 and April 2014 in a district general hospital. The QI measures were derived from process mapping a rectal cancer diagnostic pathway. The primary outcome was to assess the tissue biopsy process diagnostic yield. The secondary outcome included total breaches for a 62-day target in the pre- and post-QI study phases.

There was no significant difference in demographics or referral mode in both study phases. There were 81 patients in the pre-QI phase compared to 38 in the post-QI phase, 68 per cent and 74 per cent were referred via the two-week wait urgent pathway, respectively. Diagnostic tissue biopsy process yield improved from 58.1 to 77.6 per cent after implementing the QI measure (p=0.02). The 62-day target breach was reduced from 14.8 to 3.5 per cent (p=0.42).

Simple QI measures can achieve significant improvements in rectal cancer diagnostic tissue biopsy process yields. A multidisciplinary approach, involving process mapping and cause and effect modelling, proved useful tools.

A process mapping exercise and QI measures resulted in significant improvements in diagnostic yield, reducing the episodes per patient before histological diagnosis was confirmed.

THE Librarian faces one of the turning times in library history. The flow of progress has not yet begun, the shortages and consequent imperious demands for food, housing and clothing stand in the way of the beginning, except on paper. How long the interregnum will last none can say. The authorities, which are a reflection in some ways of the Parliamentary party in power, are well‐disposed towards libraries; the official handbook of the Labour Party proves that; but the clamour of the needs we have mentioned deafens everybody to library needs—except in certain instances. For example, the rebuilding and enlarging of the staff at Holborn is an encouraging sign. Of more potential significance is the working out of the so‐called National Charter. It has involved many towns in the task of creating an establishment for each public department. Thus, in one library system we hear that each branch or department may claim a librarian and a deputy both on the A.P.T. scale, but all the assistants are either general or clerical. Some assistants we hear have applied to be of clerical grade as the maximum salary is greater than in the general. This we suggest is putting cash before status because it is accepted as an axiom that a clerk has only clerical qualifications and potentialities, while a general assistant may aspire, when there is a vacancy and if he have certificates, to the professional status. The grading in the particular library mentioned has rather a petrifying effect in that no assistant can get into the professional grade unless his librarian or deputy departs. Possibly this sort of thing may alter, but the fact remains for good or ill—it is not all ill by any means—that no library is able to attract men from another except to a definitely higher post.

A CORRESPONDENT complains that he has undertaken a course for his final examination, after spending six years from Dunkirk to the Elbe far removed from library opportunities—only to find that librarians and libraries are building up their staffs now. The Times Literary Supplement, he says, carries column after column of advertisements of desirable posts for which he, as he thinks, is a desirable and legitimate aspirant, but he is barred by his academic obligations. This appears to be a genuine grievance and we place it first in these notes in the hope that authorities, and especially librarians, may be induced to consider it. It may be answered that there is a present urgent need to tune up libraries of every kind to meet the great public need and that many of them have already waited some years. It is perhaps a pity that they did not wait a little longer so that the men who deserve most of the country could have been brought into the competition.

Reports from the south‐east of England that housewives have been purchasing packets of “ glitter ” consisting of powdered glass, lacquered, coated with silver and sometimes dyed, for the purpose of decorating their cakes makes one wonder seriously whether we Britons are any more of a thinking race than our coloured brethren of London and other large centres, who report has it, consume large quantities of canned cat and dog meat as a sandwich spread. In the first case, although the so‐called “ glitter ” was never prepared for use as a cake decoration, the manufacturers concerned have given an assurance that in future packets will be labelled that the contents are not for eating !