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Refractive index sensing is attracting extensive interest. Limited by the weak light–matter interaction and the broad bandwidth of resonance, the figure of merit (FoM) of terahertz (THz) sensors is much lower than their counterparts in visible and infrared regions. Here, these two issues are addressed by incorporating a microfluidic channel as a slot layer into a grating slot waveguide (GSW), where guided‐mode resonance results in a narrowband resonant peak and the sensitivity increases remarkably due to the greatly concentrated electromagnetic fields in the slot layer. Both reflective and transmissive sensors are developed with the calculated quality (Q) factors two orders of magnitude larger than metamaterial and plasmonic sensors, and the sensitivities one order of magnitude larger than grating waveguide sensors, contributing to a record high FoM of 692. The measured results match well with the simulations considering the fabrication errors, where the degeneration of narrowband transmission peaks in experiments is attributed to the error of the microfluidic channel height and the divergence of the incident beam. The proposed unity‐integrating configuration with simultaneous optimizations of the resonance mechanism, and the spatial overlap between the sensing field and the analytes shows the potential for high sensitivity bio and chemo sensing. A terahertz sensor consisting of a grating slot waveguide (GSW) is presented with ultrahigh figure of merit over 600, where the slot acts as both the microfluidic channel and the waveguide layer. The excellent performance attributes to high Q resonance in the GSW and strong electromagnetic field confinement in the slot layer, that is, large spatial overlap with the analyte. [ABSTRACT FROM AUTHOR]

Spectroscopy is widely used in biomedicine, agriculture, remote sensing, industrial process monitoring, etc. The emerging on‐chip integration techniques further extend these applications to on‐site and portable operating modes. However, realizing high‐applicability and low‐cost spectroscopy chips is still a major challenge particularly in infrared due to the requirements on a large number of spectral channels. Here, a compact and low‐cost near‐infrared spectral sensing platform is demonstrated, releasing the burden of scaling up the spectral channel and simultaneously keeping a high accuracy in chemical classification. The monolithically integrated spectral sensor consists of a small amount of plasmon‐modulated narrowband photodetection units and operates with on‐chip photoelectric responses via a statistical machine learning method. Both plasmonic resonances with low spectral correlation and advanced regression algorithms contribute to high sensing accuracy in the case of limited hardware resources. Chemical concentration quantification, plastic sorting, and scanning spectral imaging are realized using such a sensor with up to twelve spectral channels. This concept avoids the uncertainty of various spectral reconstruction algorithms, high cost, and processing complexity and therefore provides promising strategies for miniaturized spectral sensing platforms. [ABSTRACT FROM AUTHOR]

Lack of commitment to infertility investigations and treatment was not the reason for patient dropout. [Copyright &y& Elsevier]

: ObjectiveTo determine whether anovulation exists in normally menstruating women.: MethodsIn a database of 550 consecutive couples seeking pregnancy, results of the midluteal serum progesterone level analysis planned for 7 days before the onset of the next menses were examined in women with predictable cycles shorter than 35 days.: ResultsOf the 550 couples seeking pregnancy, 410 of the female partners (74.5%) were eumenorrheic. Fifteen of these women (3.7%) had apparently anovulatory cycles with a progesterone lower than the normal ovulatory value of 15 nmol/L. Further examination showed that four of the 15 women (26.7%) had an isolated prolonged cycle, whereas an additional four (26.7%) failed to have their sample taken at an appropriate time. One (6.7%) had a low progesterone level that was normal in the subsequent cycle. Two patients (13.3%) were older than 40, both having elevated early follicular follicle-stimulating hormone levels. One patient (6.7%) conceived in the following menstrual cycle without further evaluation. The three remaining women (20%) showed consistently apparently anovulatory cycles. However, the levels were exclusively above the follicular range.: ConclusionOur findings cast doubt on the concept of anovulatory cycles in eumenorrheic women and suggest that further examination of the lower level of ovulatory progesterone may indeed be necessary. [Copyright &y& Elsevier]

Advances in micro and nanophotonic technologies allow us to imagine building a Supercamera that is capable of imaging in all regions of the light spectrum using a single integrated image sensor. An essential part of such a device will be multi‐spectral materials to make filter technologies to discriminate and spatially multiplex many sensors on a focal plane array. Structured photonic materials, such as plasmonic filters and metamaterial absorbers, exhibit engineered optical characteristics that are dependent on the properties of periodically arrayed subwavelength unit cells. In the article on pp. 1625–1633, McCrindle et al. present the design, simulation, fabrication and characterisation of an infrared plasmonic filter set for multi‐spectral imaging applications. The authors have also demonstrated that it is possible to combine infrared plasmonic filter hole arrays with optical plasmonic filters and a terahertz metamaterial absorber to create a new hybrid synthetic multispectral material. The resultant synthetic multi‐spectral material is capable of filtering three optical wavelengths, a single nearinfrared wavelength, a single short‐wave infrared wavelength, and two mid‐infrared wavelengths, whilst simultaneously absorbing a single terahertz frequency. [ABSTRACT FROM AUTHOR]

Answers a series of health-related questions. Clinical management of tetanus toxoid allergy; Effects of exogenous steroids on basal body temperature; Manifestations and treatment of chronic lower abdominal pain.

Introduction: Balloon kyphoplasty provides symptomatic relief of vertebral compression fractures in elderly patients. Peri-operative complications are rare; however, they can potentially be devastating. To the best of our knowledge, complications during balloon kyphoplasty have not been described previously in published case reports.Case Presentation: A 66-year-old man who was a farmer of Caucasian origin presented with a 6-month history of back pain after a fall. We discovered a significant T12 wedge compression fracture, so we performed a T12 balloon kyphoplasty. Approximately 2 weeks after being discharged from our hospital, the patient presented with increasing back pain. He presented for a second time with excruciating pain on the left side of his thoracolumbar region, so he was admitted to our ward. X-rays did not show any further fractures or compromise, but magnetic resonance imaging showed extensive edema in the T11 and L1 vertebral bodies as well as fluid tracking from the T11-T12 disc into the vertebral body. Nine days after being discharged, the patient presented to the outpatient clinic with severe back pain. Magnetic resonance imaging at that visit showed edema at the levels above and below the T11/T12 disc. He was put into a brace and given 300mg of morphine, which did not provide any pain resolution. Posterior instrumentation from T9 to L2 (pedicle fixation of T9-T10 as well as L1-L2, rods in between and a crosslink above T11-T12) was performed as the final treatment, and the patient was discharged uneventfully.Conclusion: Patients presenting with residual pain over a previous balloon kyphoplasty level should raise high suspicion for a fracture or complication involving the levels above and/or below the balloon kyphoplasty. The best way to treat fractures that develop after a failed balloon kyphoplasty is to instrument and fuse posteriorly. Our present case report shows that a high level of suspicion for possible new fractures should be maintained for all similar cases. [ABSTRACT FROM AUTHOR]

An acoustic particle manipulation system is presented, using a flexible printed circuit board formed into a regular heptagon. It is operated at 4 MHz and has a side dimension of 10 mm. The heptagonal geometry was selected for its asymmetry, which tends to reduce standing wave behavior. This leads to the possibility of having fine control over the acoustic field by varying the output phases of the transducer elements. Configurations with two and three active transducers are demonstrated experimentally. It is shown that with two transducers, the particles align along straight lines, the position of which can be moved by varying the relative excitation phases of the two transducers. With three active transducers, hexagonal-shaped patterns are obtained that can also be moved, again according to the phase of the excitation signals. Huygens? principle-based simulations were used to investigate the resultant pressure distributions. Good agreement was achieved between these simulations and both Schlieren imaging and particle manipulation observations. [ABSTRACT FROM AUTHOR]

The authors have imprinted high aspect ratio artificial dielectric quarter wave plates (QWPs) on polymers for use at 2.6, 3.2, and 3.8 THz. The QWPs are imprinted on high density polyethylene using silicon masters. The grating period for the quarter wave plates is 60 μm. Deep gratings of 330, 280, and 230 μm are used to obtain a π/2 phase retardance between TE and TM polarizations propagating through the QWPs. An inductively coupled plasma etch process was used to create the silicon masters for the imprint. A combination of heat and pressure was used for the imprinting process. Two plates, fixed in a back-to-back configuration, were used for each QWP. A highest aspect ratio (grating height/grating width) of 7 was obtained using the imprint technology. [ABSTRACT FROM AUTHOR]

An obituary for researcher Simon Triger is presented.

Failure to adhere to therapy is common in couples with fertility problems. Explaining why is difficult and worthy of further investigation without stigmatizing assumptions. [Copyright &y& Elsevier]

This article presents the simulation, fabrication, and experimental characterization of a surface plasmonic resonance (SPR) sensor integrated with an acoustic sensing compatible substrate. The SPR sensor is designed to work in the visible region with gold nanodisc arrays fabricated on LiNbO3, which is both piezoelectric and birefringent. A linear relationship between resonance wavelength and varying liquid refractive indices were observed in experiments, and a sensitivity of 165 nm/refractive index unit was obtained. Polarization effects of the birefringent property of the Y-cut LiNbO3 substrate have been investigated, which can also be applied to X-cut LiNbO3. Our study demonstrates the feasibility of an SPR sensor device utilizing a birefringent substrate, which has acoustic wave compatibility and can pave the way toward much more robust and flexible biosensing devices. [ABSTRACT FROM AUTHOR]

It is extremely important for biodiversity conservation that protected areas are resilient to a range of potential future perturbations. One of the least studied influences on protected area resilience is that of disease. We argue that wildlife disease (1) is a social-ecological problem that must be approached from an interdisciplinary perspective; (2) has the potential to lead to changes in the identity of protected areas, possibly transforming them; and (3) interacts with conservation both directly (via impacts on wild animals, livestock, and people) and indirectly (via the public, conservation management, and veterinary responses). We use southern African protected areas as a case study to test a framework for exploring the connections between conservation, endemic disease, and social-ecological resilience. We first define a set of criteria for the social-ecological identity of protected areas. We then use these criteria to explore the potential impacts of selected diseases (foot-and-mouth disease, anthrax, malaria, rabies, rift valley fever, trypanosomiasis, and canine distemper) on protected area resilience. Although endemic diseases may have a number of direct impacts on both wild animals and domestic animals and people, the indirect pathways by which diseases influence social-ecological resilience also emerge as potentially important. The majority of endemic pathogens found in protected areas do not kill large numbers of wild animals or infect many people, and may even play valuable ecological roles; but occasional disease outbreaks and mortalities can have a large impact on public perceptions and disease management, potentially making protected areas unviable in one or more of their stated aims. Neighboring landowners also have a significant impact on park management decisions. The indirect effects triggered by disease in the human social and economic components of protected areas and surrounding landscapes may ultimately have a greater influence on protected area resilience than the direct ecological perturbations caused by disease. [ABSTRACT FROM AUTHOR]

Abstract: We describe a complete lab-on-a-chip type ion-sensitive chemical sensor array system for imaging proton concentration and flow. The core of the imaging system relies on a 715.8μm×715.8μm large 64×64-pixel ISFET sensor array that is designed and fabricated in a conventional 4-metal 0.35μm CMOS process along with readout circuitry and additional electronics. The high-speed and real-time data acquisition of ∼100frame per second (fps), 40μs per pixel, results in a large amount of data that is streamed to the hard disk. Image reconstruction methods allow visualization of the dynamic behavior of chemical substances and ionic spreads over the sensor array at a resolution of the size of a pixel. The functionalities of the on-chip ion-camera device are demonstrated using appropriate acid and alkaline solutions. A pH sensitivity of 20mV/pH was achieved without modification to the foundry processed chip. [Copyright &y& Elsevier]

Surface enhanced resonance Raman spectroscopy (SERRS) is a powerful molecular sensing tool that can be-applied to a number of applications in the field of molecular diagnostics. We demonstrate that by using electron beam lithography to manipulate the nanoscale geometry of Ag split-ring resonators we can tune their optical properties such that they exhibit two independently addressable high frequency plasmon resonance modes for SERRS. This tailored multimodal, polarization dependent activity enables the split rings to act as discriminating sensors, with each resonance tuned for a particular sensing purpose. The structures are used as multiwavelength, multianalyte DNA SERRS sensors, with each resonance tuned to both the absorption wavelength of a differently colored Raman reporter molecule and its corresponding laser excitation wavelength. The ability of each resonance to independently sense small concentrations of a single DNA type from within a mixed population is demonstrated. Also shown is the effect of the split ring's dichroic response on the SERRS signal and the sensor's limit of detection of each resonance mode (switching its sensory reaction "on" and "off" depending on the orientation of the exciting light). [ABSTRACT FROM AUTHOR]

OBJECTIVE:To estimate the effect of increased menstrual flow on the loss of work.METHODS:Heavy or otherwise abnormal menstrual bleeding is a common problem among women in the reproductive age range. Until now, there has been no evidence of its effect on absences from work. We used data from the National Health Interview Survey 1999, a personal interview household survey using a nationwide representative sample of the civilian noninstitutionalized population of the United States. Participants were 3133 women aged between 18 and 64 years who reported having a natural menstrual period in the last 12 months and in the last 3 months, never having taken medication containing estrogen (except past use of oral contraceptives), and never having been told that they had reproductive cancer. Analysis was performed using data from 2805 women, 373 having self-described heavy flow and 2432 having normal flow. The main outcome measure was work loss associated with the degree of menstrual flow.RESULTS:Using binary logistic regression, age, marital status, education, family size, perception of health, and flow of menstrual periods are associated with work losses (P < .05). The odds ratio of 0.72 (95% confidence interval 0.56, 0.92) indicates that women who have a heavier flow are 72% as likely to be working as are women who have a lighter or normal flow.CONCLUSION:Menstrual bleeding has significant economic implications for women in the workplace: work loss from increased blood flow is estimated to be $1692 annually per woman. [Copyright &y& Elsevier]

ABSTRACT A novel method of introducing a notch at a point of high magnetic field in a coplanar waveguide (cpw) radial and diamond stub resonator to increase the quality factor (Q) was analyzed. For comparison, both radial- and diamond-shaped cpw resonators with and without notches were fabricated on gallium arsenide (GaAs) semi-insulating substrate at the James Watt Nanofabrication Centre and tested in the milli-metric laboratory at University of Glasgow. The notch increased the loaded Q factor of the diamond resonator by approximately 28% and good agreement was obtained between the measured and simulated loaded Q for both cpw radial and diamond resonators. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1323-1325, 2015 [ABSTRACT FROM AUTHOR]