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Perceived loneliness, an increasingly prevalent social issue, is closely associated with major depressive disorder (MDD). However, the neural mechanisms previously implicated in key cognitive and affective processes in loneliness and MDD still remain unclear. Such understanding is critical for delineating the psychobiological basis of the relationship between loneliness and MDD.
We isolated the unique and interactive cognitive and neural substrates of loneliness and MDD among 27 MDD patients (mean age = 51.85 years, 20 females), and 25 matched healthy controls (HCs; mean age = 48.72 years, 19 females). We assessed participants' behavioral performance and neural regional and network functions on a Stroop color-word task, and their resting-state neural connectivity.
Behaviorally, we found greater incongruence-related accuracy cost in MDD patients, but reduced incongruence effect on reaction time in lonelier individuals. When performing the Stroop task, loneliness positively predicted prefrontal-anterior cingulate-parietal connectivity across all participants, whereas MDD patients showed a decrease in connectivity compared to controls. Furthermore, loneliness negatively predicted parietal and cerebellar activities in MDD patients, but positively predicted the same activities in HCs. During resting state, MDD patients showed reduced parietal-anterior cingulate connectivity, which again positively correlated with loneliness in this group.
We speculate the distinct neurocognitive profile of loneliness might indicate increase in both bottom-up attention and top-down executive control functions. However, the upregulated cognitive control processes in lonely individuals may eventually become exhausted, which may in turn predispose to MDD onset.
A novel solid-clad-by-liquid method was developed to form a 10-m long by 10-mm wide by 80-μm thick Ni–5 at.% W/Ni–9.3 at.% W/Ni–5 at.% W composite tape. Three deformation routes (cold rolling, cold rolling with intermediate annealing, and cold rolling combined with warm rolling) have been investigated in short Ni–5 at.% W/Ni–9.3 at.% W/Ni–5 at.% W composite substrate. To optimize the dynamic continuous annealing parameters for the long composite substrates, air-cooled and furnace-cooled annealing procedures were compared in short Ni–5 at.% W/Ni–9.3 at.% W/Ni–5 at.% W composite substrates. Improved cube texture of 98.7% in a 10-m long by 10-mm wide by 80-μm thick Ni–5 at.% W/Ni–9.3 at.% W/Ni–5 at.% W composite substrate was achieved via warm rolling deformation at 550 °C and two-step dynamic continuous annealing (750 °C for 1 h followed by 1200 °C for 1 h). The yield strength, Curie temperature, and saturation magnetization of 176 MPa, 324 K, and 18 emu/g, respectively, were obtained.
A simple and facile stereolithography 3D printing technique was utilized to fabricate piezoelectric photopolymer-based polyvinylidene fluoride (PVDF) blends. Different process variables, such as solvent (N,N-dimethylformamide, DMF) to PVDF ratio and PVDF solution to photopolymer resin (PR) ratio, were engineered to enhance the dispersion of the PVDF into the PR so as to achieve the maximum piezoelectric coupling coefficient. Our results demonstrate that a ratio of 1:10 (PVDF:DMF) and 2 wt%-PVDF/PR was optimal for the best dissolution of the PVDF, 3D printability, and piezoelectric properties. Under these conditions, the blend generated ±0.121 nA under 80 N dynamic loading excitation. We believe that the findings of this work would promote many further studies on the mass production of flexible piezoelectric polymer blends with higher quality finished surface and design flexibility.
We report on a high-repetition-rate, high-power continuously pumped Nd:GdVO4 regenerative amplifier. Numerical simulations successfully pinpoint the optimum working point free of bifurcation instability with simultaneous efficient energy extraction. At a repetition rate of 100 kHz, a maximum output power of 23 W was obtained with a pulse duration of 27 ps, corresponding to a pulse energy of
. The system displayed an outstanding stability with a root mean square power noise as low as 0.3%. The geometry of the optical resonator and the pumping scheme enhanced output power in the
mode with a single bulk crystal. Accordingly, nearly diffraction-limited beam quality was produced with
at full pump power.
GH3536 alloy is one of the high-temperature nickel-based alloys and widely applied in aviation and aerospace industries. In this study, a combination of experiment and simulation is proposed to study the effect of processing parameters on the selective laser melting (SLM) of GH3536 powder. It is concluded that the relationship between density and laser input energy during SLM complies with a quadratic function and presents an inverted U-shaped distribution. By fitting density and input power to a quadratic polynomial, the optimal laser input energy during SLM of GH3536 alloy can be obtained. The result shows that using 275 W laser power and 960 mm/s scanning speed, the SLM GH3536 specimens can reach the maximum density. This experimental result is consistent with the simulation result obtained by analyzing molten pool dimension. Furthermore, a full process energy prediction diagram for SLM GH3536 alloy based on the simulated molten pool depth and width is proposed. The result shows that it provides an innovative and efficient method for the selection of processing parameters during SLM of GH3536 powder.
In this study, a thermal–elastic–plastic finite element model is proposed to investigate the effect of volume energy density on the temperature field, molten pool size, and residual stress distribution in the selective laser melting (SLM) process of Inconel 718 alloy. A temperature-dependent thermal–mechanical property of materials is considered, as well as the properties conversion between powder layer and solidified alloy. Within the scope of the study parameters, the simulated molten pool size increases with increasing volume energy density and exhibits linear growth relationship, which are validated by the experimental results and show a good agreement. In addition, five scanning strategies are adopted to study the effect of these scanning strategies on the residual stress distribution in this research. The results show that the residual stress distribution of SLM Inconel 718 specimen largely depends on the scanning strategy. Finally, to reveal the mechanism of residual stress formation, the restraint bar model is used to further analyze the formation mechanism of residual stress during the SLM process.
To revise an abbreviated version of the Silhouettes subtest of the Visual Object and Space Perception (VOSP) battery in order to recognize mild cognitive impairment (MCI) and determine the optimal cutoffs to differentiate among cognitively normal controls (NC), MCI, and Alzheimer’s Disease (AD) in the Chinese elderly.
A cross-sectional validation study.
Huashan Hospital, Shanghai, China.
A total of 591 participants: Individuals with MCI (n = 211), AD (n = 139) and NC (n = 241) were recruited from the Memory Clinic, Huashan Hospital, Shanghai, China.
Baseline neuropsychological battery (including VOSP) scores were collected from firsthand data. An abbreviated version of silhouettes test (Silhouettes-A) was revised from the original English version more suitable for the elderly, including eight silhouettes of animals and seven silhouettes of inanimate objects, with a score ranging from 0 to 15.
Silhouettes-A was an effective test to screen MCI in the Chinese elderly with good sensitivity and specificity, similar to the Montreal cognitive assessment and superior to other single tests reflecting language, spatial, or executive function. However, it had no advantage in distinguishing MCI from AD. The corresponding optimal cutoff scores of Silhouettes-A were 10 for screening MCI and 8 for AD.
Silhouettes-A is a quick, simple, sensitive, and dependable cognitive test to distinguish among NC, MCI, and AD patients.
Real-time Precise Point Positioning (PPP) has been evolved as a cost-effective technique for highly precise maritime positioning. For a long period, maritime PPP technology has mainly relied on the Global Positioning System (GPS). With the revitalisation of GLONASS and the emerging BeiDou navigation satellite system (BDS), it is now feasible to investigate real-time navigation performance of multi-constellation maritime PPP with GPS, BDS and GLONASS. In this contribution, we focus on maritime PPP performance using real world maritime kinematic data and real-time satellite correction products. The results show that BDS has lower position accuracy and slower convergence time than GPS. The BDS and GPS combination has the best performance among the dual-constellation configurations. Meanwhile, the integration of BDS, GLONASS and GPS significantly improves the position accuracy and the convergence time. Some outliers in the single constellation configuration can be mitigated when multi-constellation observations are utilised.
The following paper investigates the prevalence and characteristics of asymptomatic norovirus infection in the population living around oyster farm sites. Two consecutive surveys were conducted from January 2014 to December 2014 and 4549 stool samples were screened during the same time period. The total asymptomatic infection rate was 4.04% (184/4549). Norovirus infection rate was 5.20% in oyster farming population which was significantly higher compared with non-farming population where the infection rate was 3.65% (χ2 = 5.49, P < 0.05). A total of 184 NoV positive samples were identified by real time-quantitative polymerase chain reaction (RT-qPCR) and semi-nested RT-PCR and 136 sequences were obtained. The sequences were clustered into 14 genotypes. GI strains were clustered into six genotypes, including GI.2, GI.3, GI.5, GI.6, GI.8 and GI.9; while GII strains were clustered into GII.2, GII.3, GII.4, GII.5, GII.6, GII.8 and GII.13. GI.9 and GII.17 were the predominant and most prevalent genotypes, respectively. The GII.17 genotype replaced GII.4 becoming the dominant genotype in the oyster farming area in 2014. To sum up, long-term monitoring of asymptomatic infection is crucial for the detection of new variant strains and for identifying outbreaks during the early stage.
The MMSE is used to screen for cognitive impairment and estimate dementia severity. In clinical settings, conventional cut-off scores have been used to distinguish between dementia stages. However, these scores have not been validated for different populations. This study maps scores from the modified version of the MMSE to dementia stages delineated by the Diagnostic and Statistical Manual of Mental Disorders-3rd revised edition (DSM-III-R), the Clinical Dementia Rating (CDR) and Functional Assessment Staging Test (FAST). We used cross-sectional data from a tertiary hospital memory clinic. Subjects were stratified into “primary education and below” (PE) or “secondary education and above” (SE). Receiving operating characteristic (ROC) analyses and Cohen's κ were performed to determine MMSE cut-off scores for dementia stages. Our derived cut-off scores were lower compared to the conventional scores. Scores also differed between subjects of different education levels. MMSE cut-off scores were 19, 15, and 9 for CDR stages 1, 2, and 3 respectively in PE subjects, and 23, 17, and 10 for SE subjects. Cut-off scores were comparable for staging by DSM-III-R Criteria and FAST. There is a need for locally derived stage-specific MMSE cut-off scores for the Asian population adjusted for education.
To determine the prevalence of Cryptosporidium in dairy cattle in Guangdong Province, South China, 1440 fecal samples were collected from 10 farms and screened for Cryptosporidium with PCR. The overall prevalence of Cryptosporidium was 4.38% (63/1440), and the infection rates in preweaned calves, postweaned calves, heifers and adults were 6.4% (19/297), 6.19% (33/533), 1.48% (4/271) and 2.06% (7/339), respectively. Three Cryptosporidium species, Cryptosporidium andersoni (n = 33), Cryptosporidium bovis (n = 22) and Cryptosporidium ryanae (n = 8) were detected by DNA sequence analysis of the 63 positive samples, and C. andersoni was identified as the most common species on the dairy cattle farms. In preweaned calves, C. bovis was the most prevalent species (9/19, 47.4%). In contrast, C. andersoni was the predominant species (19/33, 57.6%) in postweaned calves and the only species found in heifers and adults. The zoonotic species Cryptosporidium parvum was not detected in this study. Twenty-four C. andersoni isolates were successfully classified into three multilocus sequence typing (MLST) subtypes. MLST subtype A4,A4,A4,A1 was the predominant subtype, and MLST subtype A2,A5,A2,A1, previously found in sheep, was detected in cattle for the first time. A linkage disequilibrium analysis showed that the C. andersoni isolates had a clonal genetic population structure. However, further molecular studies are required to better understand the epidemiology of Cryptosporidium in Guangdong.
We present a recent progress of the SG-II 5PW facility, which designed a multi-petawatt ultrashort pulse laser based on optical parametric chirped-pulse amplification (OPCPA). The prior two optical parametric amplifiers have been accomplished and chirped pulses with an energy of 49.7 J and a full-width-at-half-maximum (FWHM) spectrum bandwidth of 85 nm have been achieved. In the PW-scale optical parametric amplification (OPA), with the pump pulse that has an energy of 118 J from the second harmonic generation of the SG-II 7th beam, the pump-to-signal conversion efficiency is up to 41.9%, which to the best of our knowledge is the highest among all of the reported values for OPCPA systems. The compressed pulse is higher than 37 J in 21 fs (1.76 PW), and the focal spot is
after the closed-loop corrections by the adaptive optics. Limited by the repetition of the pump laser, the SG-II 5PW facility operates one shot per hour. It has successfully been employed for high energy physics experiments.
Knotless barbed sutures can eliminate knot tying during the bariatric surgery (BS) (1). Since effects reported by patients and surgeons are ambiguous, the aim of this study was to establish the safety and efficacy of barbed sutures for intestinal sutures to close the gastrojejunal anastomosis in obese patients undergoing BS.
PubMed, EMBASE, Cochrane Register of Clinical Studies, and ClinicalTrials.gov were searched for randomized controlled trials (RCTs) and cohort studies comparing barbed sutures with conventional sutures in BS (until 30 June 2016). Quality assessment was conducted using to Cochrane recommendations. Review Manager was applied to analyze the data, and we sequentially omitted each study to perform sensitivity analyses.
A total of five cohort studies (low to moderate risk of bias) (n = 859), and no RCTs provided eligible patients. BS includes laparoscopic Roux-en-Y gastric bypass and Laparoscopic sleeve gastrectomy. Comparing to conventional sutures, pooling data showed that suture time (Mean Difference, MD = -5.73, 95 percent Confidence Interval, CI -6.25 to -5.21, P < .01) and operative time (MD = - 7.67, 95 percent CI -10.49 to -4.85, P < .01) decreased significantly in the barbed group. Although the postoperative complications did not suggest significant changes (Odds Ratio, OR = 1.56, 95 percent CI .79 to 3.07, P = .2), the pooling results of hospital stay suggested that a significantly longer duration happened in the barbed groups, despite the fact that there may be only 0.18 day longer. (MD =0.18, 95 percent CI .06 to .29, P = .003).
The barbed suture is an effective and safe surgical technique in BS. More evidence with randomized design, larger sample sizes and longer follow up need to compel validations of this state-of-the-art product in the future (2,3).
Knotless barbed sutures can eliminate knot tying when patients are undergoing cosmetic surgery (CS). Although benefits reported on clinical outcomes are obvious, many studies have failed to demonstrate the potential for barbed sutures to mitigate adverse events. Thus, this study aimed to determine the safety of knotless barbed suture in CS.
PubMed, EMBASE, Cochrane Register of Clinical Studies, and ClinicalTrials.gov were searched for randomized controlled trials (RCTs) and cohort studies comparing barbed sutures with conventional sutures in CS (until 30 June 2016). Quality assessment was conducted using Cochrane recommendations. Review Manager was applied to analyze the data, and we sequentially omitted each study to perform sensitivity analyses.
A total of five RCTs (low to moderate risk of bias) and six cohort studies (low to moderate risk of bias), proved eligible (3,481 patients). The CS included body contouring operations, breast reconstruction, lipoabdominoplasty, abdominoplasty and wound closure of cesarean delivery. Comparing to conventional sutures, pooling data showed that general adverse events of barbed sutures were not significantly different (Odds Ratio, OR = .6, 95 percent Confidence Interval, CI .24 to 1.52, P = .28), while the subgroup analysis showed that fewer adverse events occurred in cohort studies, though with high heterogeneity (I2 = 87 percent). Specifically, no significant differences were shown between barbed and traditional sutures in wound dehiscence (OR = .55, 95 percent CI .29 to 1.03, P = .06), incisional infection (OR = .56, 95 percent CI .22 to 1.48, P = .25), seroma (OR = .87, 95 percent CI .42 to 1.79, P = .70) and hematoma (OR = 1.52, 95 percent CI .29 to 7.99, P = .62).
No differences were found between knotless barbed sutures and conventional sutures generally, but the cohort studies suggested barbed sutures resulted in fewer adverse events with longer follow-up. Thus barbed sutures are considered a safe surgical technique in CS. More evidence with larger sample sizes and longer follow up are needed to confirm the advantages of this technique in the future.
Heart failure (HF) is a major public health problem worldwide and in Asia. Sacubitril/valsartan reduces cardiovascular death and hospitalizations for HF. However, decision makers need to determine whether its benefits are worth the additional costs, given the low-cost generic status of current standard of care.
Using a Markov model, we projected lifetime clinical and economic outcomes of sacubitril/valsartan versus enalapril for 66-year-old patients with HF in Singapore. Key health states included New York Heart Association (NYHA) classes; patients in each state incurred a monthly risk of hospitalization for HF and cardiovascular death. Probabilities of events were based on the PARADIGM-HF trial. The uncertain treatment effect of sacubtril/valsartan in Asian patients was modelled using a hazard ratio (HR) of 1 as upper limit in sensitivity analyses. Utilities were obtained from published literature. Local national epidemiological and cost data were applied. Analyses were conducted from the Singapore healthcare payer's perspective. Both one-way and Probabilistic Sensitivity Analyses (PSA) based on 10,000 Monte Carlo simulations were performed.
Compared to enalapril, sacubitril/valsartan was associated with an incremental cost-effectiveness ratio (ICER) of SGD74k (USD52k) per quality-adjusted life year (QALY) gained. The cost-effectiveness of sacubitril/valsartan was highly dependent on its effectiveness in reducing the risk of cardiovascular death. However, this was uncertain, particularly in the Asian subgroup, where results were not statistically significant. In sensitivity analyses using results from Asian patients, the ICERs ranged from SGD41k (USD30k) to SGD1.3 million (USD 0.94 million) per QALY gained. PSA showed the probability of sacubitril/valsartan being cost-effective was below 1 percent, 12 percent and 71 percent at thresholds of SGD20k (USD14k), SGD50k (USD36k) and SGD100k (USD 72k) per QALY gained, respectively.
Given the uncertain ICER, sacubtril/valsartan may not provide good value for money compared to enalapril in reducing cardiovascular morbidity and mortality in patients with HF at the current daily cost. Our study highlights the cost-benefit trade-off that healthcare professionals and patients face when considering HF therapy.
For treatment of patients diagnosed with schizophrenia, comparative
long-term effectiveness of antipsychotic drugs to reduce relapses when
minimising adverse effects is of clinical interest, hence prompting this
To evaluate the comparative long-term effectiveness of antipsychotic
We systematically searched electronic databases for reports of randomised
controlled trials (RCTs) of antipsychotic monotherapy aimed at reducing
relapse risks in schizophrenia. We conducted network meta-analysis of 18
antipsychotics and placebo.
Studies of 10 177 patients in 56 reports were included; treatment
duration averaged 48 weeks (range 4–156). Olanzapine was significantly
more effective than chlorpromazine (odds ratio (OR) 0.35, 95% CI
0.14–0.88) or haloperidol (OR=0.50, 95% CI 0.30–0.82); and fluphenazine
decanoate was more effective than chlorpromazine (OR=0.31, 95% CI
0.11–0.88) in relapse reduction. Fluphenazine decanoate, haloperidol,
haloperidol decanoate and trifluoperazine produced more extrapyramidal
adverse effects than olanzapine or quetiapine; and olanzapine was
associated with more weight gain than other agents.
Except for apparent superiority of olanzapine and fluphenazine decanoate
over chlorpromazine, most agents showed intermediate efficacy for relapse
prevention and differences among them were minor. Typical antipsychotics
yielded adverse neurological effects, and olanzapine was associated with
weight gain. The findings may contribute to evidence-based treatment
selection for patients with chronic psychotic disorders.
Multiwall carbon nanotubes (MWCNTs) are utilized to resolve low coupling coefficient issue by dispersing MWCNTs in poly(vinylidene fluoride) matrix to create stress reinforcing network, dispersant, and electron conducting functions for barium titanate (BT) nanoparticles. Various BT and MWCNT percentages of nanocomposite film are fabricated by FDM three-dimensional (3D) printing which can simplify the fabrication process as well as lower cost and design flexibility. Increasing MWCNTs and BT particles gradually increase piezoelectric coefficient (d31) by 0.13 pC/N with 0.4 wt%-MWCNTs/18 wt%-BT. These results provide not only a technique to print piezoelectric nanocomposites but also unique materials combination for sensor application.
Population decline among Asian horseshoe crabs in Asia is increasingly reported, but knowledge of their population and ecological status in China is limited. We conducted community interviews in 30 fishing villages around Beibu Gulf in Guangxi, China, to collect distribution information about the potential spawning/nursery grounds of Tachypleus tridentatus and Carcinoscorpius rotundicauda, and any imminent threats to their populations. Based on the results from 400 respondents we identified 45 potential spawning/nursery grounds distributed widely along the shores of Beibu Gulf. We visited 10 of these sites and verified the presence of juvenile horseshoe crabs by field surveys. Nearly all respondents reported an overall depletion in horseshoe crab populations from these 45 sites, which they attributed mainly to unsustainable fishing practices. Respondents who reported having seen horseshoe crab mating pairs on shores were mostly older people, which may suggest a considerable reduction in horseshoe crabs coming to the shores to spawn in recent years. The mean daily harvest of adult T. tridentatus offshore, as indicated by fishers, has declined from c. 50–1,000 in the 1990s to 0–30 individuals during 2011–2016. Our Wisdom of Crowds approach, supported by confirmatory field surveys, is a cost-effective method for assessing the population status of horseshoe crabs, and the level of threat they face. Similar approaches with other species are likely to be particularly valuable in the Asia–Pacific region, where well-structured population monitoring is largely unaffordable.