To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
The effect of three green gram cultivars (PDM 54, PUSA BAISAKHI and SAMRAT) on the biology of Spilosoma obliqua Walker (Lepidoptera: Arctiidae) was studied using age-stage, two-sex life table. We also studied food utilization efficiency measures of larvae on green gram cultivars. The nutritional and antinutritional factors of leaves of green gram cultivars were determined. The preadult development time of S. obliqua was shortest on PDM 54 (35.54 days) and longest on SAMRAT (39.29 days). The fecundity was highest on PDM 54 (318.32) and lowest on SAMRAT (250.20). The net reproductive rate (R0) ranged from 37.53 on SAMRAT to 79.58 on PDM 54. The intrinsic rate of increase (r) was higher on PDM 54 (0.1148 day−1) and PUSA BAISAKHI (0.1018 day−1) than SAMRAT (0.0875 day−1). The finite rate of increase (λ) was lowest on SAMRAT (1.0915 day−1). Mean generation time (T) was shortest on PDM 54 (38.12 days) and longest on SAMRAT (41.42 days). Population projection revealed that the population growth was slowest on SAMRAT. The growth rate of sixth instar larvae was highest on PDM 54 and lowest on SAMRAT. The lower level of nutritional factors such as total carbohydrates, proteins, lipids, amino acids and nitrogen content, and a higher level of antinutritional factors such as total phenols, flavonols and tannins influenced higher development time and lower fecundity of S. obliqua on SAMRAT than other cultivars. These findings suggested that SAMRAT is a less suitable cultivar to S. obliqua than other cultivars, and this cultivar can be promoted for cultivation.
Item 9 of the Patient Health Questionnaire-9 (PHQ-9) queries about thoughts of death and self-harm, but not suicidality. Although it is sometimes used to assess suicide risk, most positive responses are not associated with suicidality. The PHQ-8, which omits Item 9, is thus increasingly used in research. We assessed equivalency of total score correlations and the diagnostic accuracy to detect major depression of the PHQ-8 and PHQ-9.
We conducted an individual patient data meta-analysis. We fit bivariate random-effects models to assess diagnostic accuracy.
16 742 participants (2097 major depression cases) from 54 studies were included. The correlation between PHQ-8 and PHQ-9 scores was 0.996 (95% confidence interval 0.996 to 0.996). The standard cutoff score of 10 for the PHQ-9 maximized sensitivity + specificity for the PHQ-8 among studies that used a semi-structured diagnostic interview reference standard (N = 27). At cutoff 10, the PHQ-8 was less sensitive by 0.02 (−0.06 to 0.00) and more specific by 0.01 (0.00 to 0.01) among those studies (N = 27), with similar results for studies that used other types of interviews (N = 27). For all 54 primary studies combined, across all cutoffs, the PHQ-8 was less sensitive than the PHQ-9 by 0.00 to 0.05 (0.03 at cutoff 10), and specificity was within 0.01 for all cutoffs (0.00 to 0.01).
PHQ-8 and PHQ-9 total scores were similar. Sensitivity may be minimally reduced with the PHQ-8, but specificity is similar.
We investigated human understanding of different network visualizations in a large-scale online experiment. Three types of network visualizations were examined: node-link and two different sorting variants of matrix representations on a representative social network of either 20 or 50 nodes. Understanding of the network was quantified using task time and accuracy metrics on questions that were derived from an established task taxonomy. The sample size in our experiment was more than an order of magnitude larger (N = 600) than in previous research, leading to high statistical power and thus more precise estimation of detailed effects. Specifically, high statistical power allowed us to consider modern interaction capabilities as part of the evaluated visualizations, and to evaluate overall learning rates as well as ambient (implicit) learning. Findings indicate that participant understanding was best for the node-link visualization, with higher accuracy and faster task times than the two matrix visualizations. Analysis of participant learning indicated a large initial difference in task time between the node-link and matrix visualizations, with matrix performance steadily approaching that of the node-link visualization over the course of the experiment. This research is reproducible as the web-based module and results have been made available at: https://osf.io/qct84/.
The recovery and recrystallization of cold rolled copper during reverse bending fatigue at room temperature has been studied with x-ray diffraction, optical microscopy and transmission electron microscopy techniques. Recovery of x-ray line breadth was recorded as a function of number of cycles at all strain amplitudes investigated. Recrystallization was observed to take place only at small strain amplitudes (life of 106 to 107 cycles). The rate of nucleation of the recrystallized grains increases with increasing strain amplitude and is a linear function of the number of cycles. The formation and growth of the grains was confined to regions near the surface of the specimen. Since comparable thermal recovery occurs at approximately 435°F it is concluded that the dynamic generation and migration of numerous point defects during fatigue is responsible for the room temperature recrystallization.
A Warren-Averbach1-4 X-ray line profile analysis was applied to broadened X-ray diffraction peaks from copper deformed in fatigue. The copper specimens were fatigued by four-point bending at peak-strain amplitudes between 0.00105 and 0.00442 in./in., and measurements were made at various fractions of the total fatigue life. The analysis results in an estimation of (a) an average coherently diffracting domain size normal to the diffracting planes and (b) an rms strain distribution function where the strain normal to the diffracting planes is averaged over a given distance at all points in the diffracting crystals and expressed as a function of averaging distance.
Prior to fatigue cycling, the annealed copper exhibited extinction, which reduced the integrated intensity from the low-angle reflections. After fatigue cycling, the integrated intensity increased with increasing strain amplitude of fatigue. The integrated intensities and the rms strains were established during the first few percent of the fatigue life and were found to increase with fatigue strain amplitude. The measured strains were larger in the <100> direction than in the <111> direction, but the absolute values were small. On the basis of transmission electron microscopy of thin foils, these results may be explained by assuming the strains are due to the presence of numerous dislocation dipoles.
Trait-specific characterization of rice landraces has significant potential for germplasm management, varietal identification and mining of novel gene/allele for various traits. In the current study, we have characterized 98 unique rice landraces collected from coastal regions of India, affected by submergence and salinity, based on Sub1 and Saltol quantitative trait loci (QTL) linked microsatellite markers. Among these genotypes, four genotypes (IC536558, IC536559, IC536604 and IC536604-1) collected from Kerala and two genotypes (AC34902 and IC324589) collected from West Bengal were identified with tolerance to submergence and salinity stress. A high level of genetic diversity of He = 0.349 and 0.529 at Sub1 and Saltol QTL region was detected by QTL-linked microsatellite markers, respectively. At Sub1 region one genotype, AC34902, was detected with maximum allelic similarity with FR13A, a known submergence tolerant variety. Besides, five genotypes (IC211188-1, IC536604-1, IC536604, IC536558 and IC536559) showed comparatively close genetic relationship with the salt tolerant variety FL478 for Saltol QTL and were clustered together in the neighbour joining dendrogram. Considering the haplotype structure, five genotypes (IC203801, IC203778, IC324584, IC413608 and IC413638) were identified which did not contain any common allele similar to FR13A but were still tolerant to submergence. These individuals need further characterization for identification of new alleles responsible for their tolerance.
Different diagnostic interviews are used as reference standards for major depression classification in research. Semi-structured interviews involve clinical judgement, whereas fully structured interviews are completely scripted. The Mini International Neuropsychiatric Interview (MINI), a brief fully structured interview, is also sometimes used. It is not known whether interview method is associated with probability of major depression classification.
To evaluate the association between interview method and odds of major depression classification, controlling for depressive symptom scores and participant characteristics.
Data collected for an individual participant data meta-analysis of Patient Health Questionnaire-9 (PHQ-9) diagnostic accuracy were analysed and binomial generalised linear mixed models were fit.
A total of 17 158 participants (2287 with major depression) from 57 primary studies were analysed. Among fully structured interviews, odds of major depression were higher for the MINI compared with the Composite International Diagnostic Interview (CIDI) (odds ratio (OR) = 2.10; 95% CI = 1.15–3.87). Compared with semi-structured interviews, fully structured interviews (MINI excluded) were non-significantly more likely to classify participants with low-level depressive symptoms (PHQ-9 scores ≤6) as having major depression (OR = 3.13; 95% CI = 0.98–10.00), similarly likely for moderate-level symptoms (PHQ-9 scores 7–15) (OR = 0.96; 95% CI = 0.56–1.66) and significantly less likely for high-level symptoms (PHQ-9 scores ≥16) (OR = 0.50; 95% CI = 0.26–0.97).
The MINI may identify more people as depressed than the CIDI, and semi-structured and fully structured interviews may not be interchangeable methods, but these results should be replicated.
Declaration of interest
Drs Jetté and Patten declare that they received a grant, outside the submitted work, from the Hotchkiss Brain Institute, which was jointly funded by the Institute and Pfizer. Pfizer was the original sponsor of the development of the PHQ-9, which is now in the public domain. Dr Chan is a steering committee member or consultant of Astra Zeneca, Bayer, Lilly, MSD and Pfizer. She has received sponsorships and honorarium for giving lectures and providing consultancy and her affiliated institution has received research grants from these companies. Dr Hegerl declares that within the past 3 years, he was an advisory board member for Lundbeck, Servier and Otsuka Pharma; a consultant for Bayer Pharma; and a speaker for Medice Arzneimittel, Novartis, and Roche Pharma, all outside the submitted work. Dr Inagaki declares that he has received grants from Novartis Pharma, lecture fees from Pfizer, Mochida, Shionogi, Sumitomo Dainippon Pharma, Daiichi-Sankyo, Meiji Seika and Takeda, and royalties from Nippon Hyoron Sha, Nanzando, Seiwa Shoten, Igaku-shoin and Technomics, all outside of the submitted work. Dr Yamada reports personal fees from Meiji Seika Pharma Co., Ltd., MSD K.K., Asahi Kasei Pharma Corporation, Seishin Shobo, Seiwa Shoten Co., Ltd., Igaku-shoin Ltd., Chugai Igakusha and Sentan Igakusha, all outside the submitted work. All other authors declare no competing interests. No funder had any role in the design and conduct of the study; collection, management, analysis and interpretation of the data; preparation, review or approval of the manuscript; and decision to submit the manuscript for publication.
Secondary carbonate deposits (similar to speleothems) in urban undergrounds, have been recently highlighted as powerful archives for reconstruction of the historical anthropogenic imprint on the environment. The precise chronology of these secondary carbonate deposits is a key issue for the accurate time reconstruction of environmental conditions. We present three 14C data sets for urban speleothem-like deposits that developed in contrasted man made environments. The first one was sampled in an underground technical gallery of the Palace of Versailles (France), and the other two in a manhole (Saint-Martin spring) of a historical underground aqueduct in Paris (France). The comparison of these records with the bomb peak and relative chronology (laminae counting) allowed us to identify: i) fast carbon transfer from the atmosphere to the urban underground; ii) a high proportion of dead carbon and a high damping effect in relation to possible old carbon stored within urban soils and/or the influence of local fossil carbon burning. This study also shows that the lamination of these deposits is bi-annual in these highly urbanized sites.
Our conventional energy reserves are limited and have severe environmental impact. There has been all round focus on the development of renewable energy primarily due to these facts, as well as from the perspective of energy security, climate change and energy access. Solar energy has been the Earth's most available energy source, capable of providing many times the total energy demand. Solar Photovoltaic (SPV) deals with conversion of sunlight into electricity. Governments across the world have realized the importance of solar power and over 60 countries have introduced feed-in tariffs, capital subsidies and incentives for productions to promote wider adoption and advancement of SPV. The average growth rate of global SPV capacity has been close to 40%, with the total installed capacity now approaching 350GWP. Renewable energy initiatives, particularly SPV, have picked up pace in India also. The Jawaharlal Nehru National Solar Mission (JNNSM) has been a major initiative of the Government of India to give an impetus to the domestic solar power industry. It sets an ambitious target of 20 GW of solar power capacity by 2022. Several State Governments have announced independent policies in SPV.
Solar PV systems [1–7] occupy a very important place in the SPV value chain (Figure 9.1). As it comes at the end point of the value chain, it decides the amount of power finally supplied. The power generated by a SPV system depends on the previous operations of the value chain as well. In the crystalline silicon (c-Si) technology, the type of wafers (mono or multi) and the efficiency of the solar cells, decided by the cell manufacturing technology, play a very important role. Assembly of the solar cells to make modules has been somewhat straightforward for c-Si technology. Thin film technology (a-Si, CdTe, CIGS, etc.) takes a different route in the value chain diagram (Figure 9.1). The modules are made directly by the Chemical Vapour Deposition (CVD) technique to deposit thin layers of appropriate materials on a conductive glass substrate to form p-n junction solar cell. In this case also the efficiency is decided by several factors such as material (Si, CdTe, CIGS, etc.), structure (amorphous, microcrystalline, etc.) and configuration (single junction, tandem junction, etc.).
There has been rising interest followed by extensive research on organic and polymer solar cells in the last three decades. Organic semiconductors have made great strides since conductivity  and electroluminescence  in Anthracene were studied in the 1960s by Kallmann and his group. Electronic processes in organic materials have been thoroughly discussed by Pope and Swinberg . Rapid progress in the field of organic materials is exemplified by the commercial success of Organic Light Emitting Diodes (OLEDS) in mobile phones and other applications. This has been possible through the tailor-making of the properties of organic semiconductors to emit light across the visible spectrum from blue to red . Recently Heliatek , a German firm, has achieved a record conversion efficiency of 13.2% for an Organic Photovoltaic (OPV) Multi-junction (MJ) cell using small molecules. The cell has three absorber layers for absorbing light from the near infrared, red and green wavelengths, covering the major part of the solar spectrum from 450 nm to 950 nm. Stability of the small molecules is projected for 25 years. This achievement has provided great impetus to commercial development. Thus, there is, in principle, no reason why organic solar cells with their inherent advantages, discussed below, should not usher in the third generation of solar cells [6, 7].
At the outset it is necessary to distinguish between the types of organic and polymer materials for PV applications.
Organic semiconductors can be classified into two broad types :
(a) Small molecules with molecular weight (MW) < 1000; usually deposited by physical vapour deposition
(b) Polymeric films with molecular weight (MW) > 10,000; deposited by casting from solution, spin coating, doctor blading screen, or inkjet printing. Though thin films are reasonably easy to form, their molecular weight and purity are hard to control.
Organic solids and polymers are generally considered to be insulators. However, both, the small molecules and polymers (Figure 5.1) used as light-absorbing materials have large conjugated systems in which carbon atoms covalently bond with alternating single and double bonds. These electrons in orbitals delocalize and form a delocalized bonding orbital with a anti-bonding orbital. The delocalized orbital forms the Highest Occupied Molecular Orbital (HOMO) and the orbital forms the Lowest Unoccupied Molecular Orbital (LUMO).
Solar Photovoltaic (SPV) modules occupy an important position in the value chain [1–5] (see Figure 9.1). Crystalline silicon (c-Si) is currently the preferred technology with a market share of about 85%. c-Si modules are made using crystalline silicon (Si) solar cells as the starting material. Several such cells are connected to make modules. The manufacturing process for c-Si modules is less complex than that for thin film modules. However, the value chain is quite long (see Figure 9.1) and more process steps in cell manufacture are required prior to module manufacturing. There are also processes, such as single crystal growth in the value chain, which require a substantial amount of electrical energy.
Thin film modules are made with an entirely different approach. These modules are made using a full size substrate (actually superstrate), typically glass with transparent conductive coating and use deposition techniques such as Plasma Enhanced Chemical Vapour Deposition (PECVD). For a-Si cells, layers of p, i and n are deposited sequentially to form the junction for PV conversion. Expensive and energy-intensive crystal growth required in c-Si technology is thus avoided. Historically, CdS/Cu2S were the first thin film cells invented in 1954. But, these were not commercially successful due to low efficiencies and degradation with time. Nowadays semiconductors such as amorphous Si (a-Si), CdTe or CIGS are used in thin film cells. Amorphous-silicon uses PECVD deposited a-Si as the active material. Single, as well as tandem junction a-Si films can be used to form a SPV module. A composite technology using a combination of a-Si and c-Si, called Heterojunction with Intrinsic Thin Layer (HIT) has also been developed. Cadmium Telluride (CdTe) and Copper Indium Gallium Selenide (CIGS) are the other two thin film materials that are being used for commercial SPV technology. Thin film technology has a much shorter value chain with lower electricity consumption than c-Si technology, PECVD being the only complex process. The cost per WP and payback period of thin film technologies is therefore lower than for c-Si technology. Another difference is that the temperature co-efficient of power output is less for thin film cells. This is an advantage in a tropical country such as India. Nevertheless, c-Si is still preferred due to higher efficiency and reliability.
Solar photovoltaics (SPV) forms an integral part of renewable energy systems that are crucial for combating global warming. Written to serve as an ideal text for students, researchers and industrial personnel, it discusses the principles of operation of photovoltaic devices, their limitations, choice of materials, and maximum efficiencies. It covers in depth discussion of new materials and devices based on organics and perovskites, and a flow-chart of the manufacture of Si, GaAs and CdTe cells, their characterization and testing. It highlights characterization, testing and reliability of solar PV modules, comparison of fixed and tracking SPV systems using concentrator cells. Economical aspects of grid-connected and stand-alone systems and a wide range of applications, from solar pumps, and street lighting to large power plants is covered in the text. Several aspects such as cell and module manufacture, characterization, testing, reliability, and system design are described considering commercial SPV manufacturing plants.