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Inclusion in nasogastric tube feeds (NGTF) of acid-sensitive, seaweed-derived alginate, expected to form a reversible gel in the stomach, may create a more normal intragastric state and modified gastrointestinal responses. This may ameliorate NGTF-associated risk of diarrhoea, upper gastrointestinal symptoms and appetite suppression. In a randomised, crossover, comparison study, undertaken in twelve healthy males, an alginate-containing feed (F + ALG) or one that was alginate-free (F-ALG) (300 ml) was given over 1 h with a 7–14-d washout period between treatments. Baseline and for 4-h post-feed initiation, MRI measurements were made to establish small bowel water content (SBWC), gastric contents volume (GCV) and appearance, and superior mesenteric artery blood flux. Blood glucose and gut peptides were measured. Subjective appetite and upper gastrointestinal symptoms scores were obtained. Ad libitum pasta consumption 3-h post-feeding was measured. F + ALG exhibited a gastric appearance consistent with gelling surrounded by a freely mobile water halo. Significant main effects of feed were seen for SBWC (P = 0·03) and peptide YY (PYY) (P = 0·004) which were attributed to generally higher values for SBWC with F + ALG (max difference between adjusted means 72 ml at 210 min) and generally lower values for PYY with F + ALG. GCV showed a faster reduction with F + ALG, less between-participant variation and a feed-by-time interaction (P = 0·04). Feed-by-time interactions were also seen with glucagon-like-peptide 1 (GLP-1) (P = 0·02) and glucose-dependent insulinotropic polypeptide (GIP) (P = 0·002), both showing a blunted response with F + ALG. Apparent intragastric gelling with F + ALG and subsequent differences in gastrointestinal and endocrine responses have been demonstrated between an alginate-containing and alginate-free feed.
The onset of magnetic reconnection in space, astrophysical and laboratory plasmas is reviewed discussing results from theory, numerical simulations and observations. After a brief introduction on magnetic reconnection and approach to the question of onset, we first discuss recent theoretical models and numerical simulations, followed by observations of reconnection and its effects in space and astrophysical plasmas from satellites and ground-based detectors, as well as measurements of reconnection in laboratory plasma experiments. Mechanisms allowing reconnection spanning from collisional resistivity to kinetic effects as well as partial ionization are described, providing a description valid over a wide range of plasma parameters, and therefore applicable in principle to many different astrophysical and laboratory environments. Finally, we summarize the implications of reconnection onset physics for plasma dynamics throughout the Universe and illustrate how capturing the dynamics correctly is important to understanding particle acceleration. The goal of this review is to give a view on the present status of this topic and future interesting investigations, offering a unified approach.
Growing evidence indicated that the glutamatergic neurotransmitter system is central to the neurobiology and treatment of mood and anxiety disorders. Riluzole, a drug currently used to slow the progression of amyotrophic lateral sclerosis, is one of the candidate drugs that modulate glutamatergic neurotransmission in the central nervous system. Recently, several open-label clinical trials have suggested that riluzole reduces symptoms of treatment-resistant major depression, obsessive-compulsive disorder and generalized anxiety disorder. Previously, we reported that riluzole rapidly attenuates the hyperemotional responses found in the olfactory bulbectomized rats. This animal model exhibits hyperemotional behavior that may mimic anxiety, aggression and irritability found in depressed patients, suggesting the possible use of riluzole in combating the symptoms of anxiety and depression. Interestingly, we first found that a single riluzole treatment had rapid anti-hyperemotional effects in the rats. In addition, we demonstrated that single riluzole treatment significantly decreased extracellular glutamate levels in medial prefrontal cortex of the rats by in vivo microdialysis examination. Our results propose a hypothesis that riluzole rapidly improve symptoms in depressed patients, as a non-monoamine-based antidepressant. In conclusion, our results suggest that a glutamate-modulating drug, riluzole, is one of the candidate drugs for new generation antidepressants and/or anxiolytics.
There is paucity of published literature on antidepressants in a cost-consequence study design.
Measuring clinical outcomes of pharmacotherapy.
Costs and consequences determination in depressive episode acute medical care.
Cost-consequence analysis;Setting-Serbian tertiary university clinic(2010-2012). Patient visits to attending psychiatrists:baseline, 3,8 weeks. HDRS-17 and Q-LES-Q-SF scale were applied in each of control visits. Resource use patterns and costs were evidenced for up to 14 weeks from study entry. Micro-costing approach allowed for most direct and indirect costs measurement. Costs were expressed in national currency-Central Serbian Dinar(1€≈115.85CSD;2012). Societal perspective and 14 weeks time horizon were adopted. Random selection of 65 depressive patients was based on clinical criteria and their assignment to either one of three different treatment protocols.5 patients were lost to follow up.
There was no statistically significant difference in terms of therapeutic response by the HDRS scores before and after introducing treatment groups(χ2=4.339; ?=0.362). QALY value increased by 11.77(SSRI group);8.93(SNRI)and 12.54 (heterocyclics). Mean cost per QALY was 9,937.51 CSD for SSRI; 7,138.27 CSD in SNRI; and 6,164.96 CSD for heterocyclics. There were 28.69 depression with free days in SSRI, 21.78 days in SNRI, and 30.59 days in heterocyclic group. Cost-effectiveness assessment was was 346.38 CSD per day(SSRI); 327.74 CSD(SNRI), and 201.54 CSD(heterocyclics).
Heterocyclic antidepressants provide highest'value for money' in terms of QALY in depressive episode treatment and its treatment is most cost effective. Cost-consequence evaluations have heavier impact to clinical decision making with regards to major depressive disorder treatment in the absence of clear clinical superiority of any major pharmacological protocol.
The primary goal of this study is to examine the effectiveness of a community-based multimodal intervention program for suicide prevention in regions where the suicide rate was relatively high compared to control regions. The secondary goal was to explore the effectiveness of a community-based multimodal intervention program for suicide prevention in highly populated regions.
NOCOMIT-J is a community-based large-scale non-randomized controlled trial, involving seven intervention regions with accompanying control regions, all with populations of statistically sufficient size. The program consists of
1) Establishing social support networks in the public health system for suicide prevention and mental health promotion;
2) A primary prevention measures of awareness campaign for the public and key personnel;
3) Secondary prevention measures for screening, counseling and outreach services for high-risk individuals;
4) After-care for individuals bereaved by suicide;
5) Suicide prevention measures especially for individuals with mental illness and work-related problems.
This study protocol was reviewed and approved by the Central Ethics Committee of the J-MISP. Additionally, the regional leaders obtained written authorization from the local governors.
The intervention started in July 2006, and continued for 3.5 years. Participants are Japanese and foreign residents living in the intervention and control regions, a total of population of 2,120,000 individuals.
Because treatment and prevention of suicide are complex and encompass many factors, success will need multi-sector collaboration. We hope that the results of NOCOMIT-J will help to develop effective strategies to reduce future suicide rate. (ClinicalTrials.gov: NCT00737165)
Reduced white matter integrity in the corpus callosum (CC) has been reported in treatment-resistant depression (TRD). rTMS is assumed to have remote effect on interconnected area with the stimulation site, and this effect is speculated to be one of the therapeutic mechanisms of rTMS treatment. In this preliminary study, we examined changes of callosal fiber integrity in 5 segments of the CC before and after rTMS treatment for TRD.
The subjects were 2 patients with treatment-resistant unipolar depression and 1 patient with treatment-resistant bipolar depression, and 24 healthy controls (HC group). The patients underwent 4-week high frequency rTMS to their left DLPFC. In diffusion tensor imaging (DTI) tractography, the CC was divided into 5 segments (orbital, frontal, parietal, temporal, and occipital) based on their cortical projection zones, and fractional anisotropy (FA) value of each segment was estimated. We compared FA in the CC between the patients and the HC groups, and examined changes of FA in the CC after rTMS treatment in the patients.
The patients showed reduced FA in the frontal, parietal, temporal, and occipital-callosal segments compared to the HC group. All patients responded to the rTMS treatment, and FA in the orbital, frontal, parietal, temporal-callosal segments increased after the rTMS treatment.
Our results suggest that white matter integrity in the CC is reduced in TRD and that increased white matter integrity in the CC might be related with the therapeutic mechanisms of rTMS treatment.
A history of previous suicide attempt is a potent risk factor for suicide later on. Crisis intervention initiated at emergency medical facilities for suicide attempters are considered important components for suicide prevention. The primary aim of this trial is to examine the effectiveness of an extensive intervention for suicide attempters in prevention of recurrent suicidal behavior, as compared with standard intervention.
ACTION-J is a single blinded randomized controlled trial. In this trial, case management intervention were provided at 19 emergency medical facilities in Japan. After psychiatric evaluation and psychological education, subjects were randomly assigned to either a group receiving continuous case management or standard care. Suicidal ideation, depressive symptoms, and general health condition were evaluated as secondary measures. The stratified logrank test based on allocation factors will be performed for all eligible participants in the intent-to-treat analysis. The study protocol was reviewed and approved by the Central Ethics Committee of the J-MISP. The protocol was also reviewed and approved by the On-site Research Ethics Committee at each participating hospital.
The intervention was initiated in July 2006. By December 2009, 914 subjects were randomized. Subject follow-up continued for 1.5 to 5 years, till the end of June 2011. ACTION-J would provide valuable information on suicide attempters and may develop effective case management to reduce future risk for suicide attempters. (ClinicalTrials.gov: NCT00736918.)
In bipolar disorder (BD), reduced white matter (WM) integrity in the corpus callosum has been reported, but its detailed localization difference has not been clarified. In this study, we examined fiber integrity in 7 segments of the corpus callosum and their relationships with clinical symptoms in BD.
Patients with BD (BD group, n = 17) and age-matched healthy controls (HC group, n = 24) were examined using diffusion tensor imaging tractography. The corpus callosum was divided into 7 segments (orbital frontal, anterior frontal, superior frontal, superior parietal, posterior parietal, temporal, and occipital) based on their cortical projection zones, and fractional anisotropy (FA) value of each segment was estimated. Differences in FA of each segment between the groups were examined using ANOVA with repeated measures. Correlations between FA of each segment and clinical symptoms (HAM-D, YMRS) were assessed using Spearman's rank correlation test in the BD group.
The BD group showed reduced FA in the orbital frontal, superior frontal, and posterior parietal-callosal segments compared to the HC group. In addition, the BD group showed a significant negative correlation between FA in the orbital frontal-callosal segment and HAM-D scores.
Our results suggest that WM integrity in the anterior part of the corpus callosum is reduced in BD and that orbital frontal-callosal disintegrity may be related with severity of bipolar depression.
The increasing number of dementia is of major public health concern. This study aims to calculate the projected number and prevalence of dementia in Japan, using data from the Toyama Dementia Survey.
The Toyama Dementia Survey was conducted 6 times in 1983, 1985, 1990, 1996, 2001, and 2014. In the 2014 survey, the subjects were randomly chosen from residents aged 65 or more in Toyama prefecture, with a sampling rate of 0.5%. Of those, 1303 men and women agreed to participate (participation rate: 84.8%). An interview with a screening questionnaire was conducted by public health nurses. Psychiatrists and public health nurses further investigated for the suspected cases of dementia and diagnosed whether the cases had dementia. The 1985–2001 surveys were conducted in a similar way, and, therefore, data from the 1985–2014 surveys were used in the analysis.
The prevalence of dementia in Toyama prefecture increased from 4.7% in 1985 to 15.7% in 2014. Using the age and sex-specific prevalence of dementia in the 2014 survey, the projected number of dementia is approximately 4.8 million (prevalence rate: 14.1%) in 2015, 6.1 million (16.7%) in 2025, and 7.2 million (19.2%) in 2035. Using the age and sex-specific prevalence of dementia as estimated by linear regression models, the projected number of dementia is approximately 4.7 million (13.9%) in 2015, 7.1 million (19.5%) in 2025, and 9.7 million (25.8%) in 2035.
The number of dementia in Japan could double in the next 20 years, which corresponds to 1 in 4 elderly people.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
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.
This study of loneliness across adult lifespan examined its associations with sociodemographics, mental health (positive and negative psychological states and traits), subjective cognitive complaints, and physical functioning.
Analysis of cross-sectional data
340 community-dwelling adults in San Diego, California, mean age 62 (SD = 18) years, range 27–101 years, who participated in three community-based studies.
Loneliness measures included UCLA Loneliness Scale Version 3 (UCLA-3), 4-item Patient-Reported Outcomes Measurement Information System (PROMIS) Social Isolation Scale, and a single-item measure from the Center for Epidemiologic Studies Depression (CESD) scale. Other measures included the San Diego Wisdom Scale (SD-WISE) and Medical Outcomes Survey- Short form 36.
Seventy-six percent of subjects had moderate-high levels of loneliness on UCLA-3, using standardized cut-points. Loneliness was correlated with worse mental health and inversely with positive psychological states/traits. Even moderate severity of loneliness was associated with worse mental and physical functioning. Loneliness severity and age had a complex relationship, with increased loneliness in the late-20s, mid-50s, and late-80s. There were no sex differences in loneliness prevalence, severity, and age relationships. The best-fit multiple regression model accounted for 45% of the variance in UCLA-3 scores, and three factors emerged with small-medium effect sizes: wisdom, living alone and mental well-being.
The alarmingly high prevalence of loneliness and its association with worse health-related measures underscore major challenges for society. The non-linear age-loneliness severity relationship deserves further study. The strong negative association of wisdom with loneliness highlights the potentially critical role of wisdom as a target for psychosocial/behavioral interventions to reduce loneliness. Building a wiser society may help us develop a more connected, less lonely, and happier society.
Patients with schizophrenia or bipolar disorder have a high risk of developing type 2 diabetes.
To identify predictive factors for hyperglycaemic progression in individuals with schizophrenia or bipolar disorder and to determine whether hyperglycaemic progression rates differ among antipsychotics in regular clinical practice.
We recruited 1166 patients who initially had normal or prediabetic glucose levels for a nationwide, multisite, l-year prospective cohort study to determine predictive factors for hyperglycaemic progression. We also examined whether hyperglycaemic progression varied among patients receiving monotherapy with the six most frequently used antipsychotics.
High baseline serum triglycerides and coexisting hypertension significantly predicted hyperglycaemic progression. The six most frequently used antipsychotics did not significantly differ in their associated hyperglycaemic progression rates over the 1-year observation period.
Clinicians should carefully evaluate baseline serum triglycerides and coexisting hypertension and perform strict longitudinal monitoring irrespective of the antipsychotic used.
Declaration of interest
The authors report no financial or other relationship that is relevant to the subject of this article. Relevant financial activities outside the submitted work are as follows. I.K. has received honoraria from Astellas, Chugai Pharmaceutical, Daiichi Sankyo, Dainippon Sumitomo Pharma, Eisai, Eli Lilly, Janssen Pharmaceutical, Kyowa Hakko Kirin, Meiji Seika Pharma, MSD, Nippon Chemiphar, Novartis Pharma, Ono Pharmaceutical, Otsuka Pharmaceutical, Pfizer, Tanabe Mitsubishi Pharma, Shionogi and Yoshitomiyakuhin; has received research/grant support from AbbVie GK, Asahi Kasei Pharma, Astellas, Boehringer Ingelheim, Chugai Pharmaceutical, Daiichi Sankyo, Dainippon Sumitomo Pharma, Eisai, Eli Lilly, GlaxoSmithKline, Kyowa Hakko Kirin, Meiji Seika Pharma, MSD, Novartis Pharma, Ono Pharmaceutical, Otsuka Pharmaceutical, Pfizer, Takeda Pharmaceutical, Tanabe Mitsubishi Pharma, Shionogi and Yoshitomiyakuhin; and is a member of the advisory boards of Dainippon Sumitomo Pharma and Tanabe Mitsubishi Pharma. Y.T. has received speaker's honoraria from Dainippon-Sumitomo Pharma, Otsuka, Meiji-Seika Pharma, Janssen Pharmaceutical, Daiichi-Sankyo Company, UCB Japan and Ono Pharmaceutical. K.U. has received honoraria from Dainippon Sumitomo Pharma, Eisai, Eli Lilly, Janssen Pharmaceutical, Kyowa Hakko Kirin, Meiji Seika Pharma, MSD, Takeda Pharmaceutical, Hisamitsu Pharmaceutical, Otsuka Pharmaceutical, Pfizer, Tanabe Mitsubishi Pharma, Shionogi and Yoshitomiyakuhin. B.Y. has received speaker's honoraria from Otsuka Pharmaceutical and Janssen Pharmaceutical. J. I. has received honoraria from Dainippon Sumitomo Pharma, Eli Lilly, Janssen Pharmaceutical, Meiji Seika Pharma, MSD, Novartis Pharma, Otsuka Pharmaceutical and Mochida Pharma.
Measurements in the infrared wavelength domain allow direct assessment of the physical state and energy balance of cool matter in space, enabling the detailed study of the processes that govern the formation and evolution of stars and planetary systems in galaxies over cosmic time. Previous infrared missions revealed a great deal about the obscured Universe, but were hampered by limited sensitivity.
SPICA takes the next step in infrared observational capability by combining a large 2.5-meter diameter telescope, cooled to below 8 K, with instruments employing ultra-sensitive detectors. A combination of passive cooling and mechanical coolers will be used to cool both the telescope and the instruments. With mechanical coolers the mission lifetime is not limited by the supply of cryogen. With the combination of low telescope background and instruments with state-of-the-art detectors SPICA provides a huge advance on the capabilities of previous missions.
SPICA instruments offer spectral resolving power ranging from R ~50 through 11 000 in the 17–230 μm domain and R ~28.000 spectroscopy between 12 and 18 μm. SPICA will provide efficient 30–37 μm broad band mapping, and small field spectroscopic and polarimetric imaging at 100, 200 and 350 μm. SPICA will provide infrared spectroscopy with an unprecedented sensitivity of ~5 × 10−20 W m−2 (5σ/1 h)—over two orders of magnitude improvement over what earlier missions. This exceptional performance leap, will open entirely new domains in infrared astronomy; galaxy evolution and metal production over cosmic time, dust formation and evolution from very early epochs onwards, the formation history of planetary systems.
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.
IR spectroscopy in the range 12–230 μm with the SPace IR telescope for Cosmology and Astrophysics (SPICA) will reveal the physical processes governing the formation and evolution of galaxies and black holes through cosmic time, bridging the gap between the James Webb Space Telescope and the upcoming Extremely Large Telescopes at shorter wavelengths and the Atacama Large Millimeter Array at longer wavelengths. The SPICA, with its 2.5-m telescope actively cooled to below 8 K, will obtain the first spectroscopic determination, in the mid-IR rest-frame, of both the star-formation rate and black hole accretion rate histories of galaxies, reaching lookback times of 12 Gyr, for large statistically significant samples. Densities, temperatures, radiation fields, and gas-phase metallicities will be measured in dust-obscured galaxies and active galactic nuclei, sampling a large range in mass and luminosity, from faint local dwarf galaxies to luminous quasars in the distant Universe. Active galactic nuclei and starburst feedback and feeding mechanisms in distant galaxies will be uncovered through detailed measurements of molecular and atomic line profiles. The SPICA’s large-area deep spectrophotometric surveys will provide mid-IR spectra and continuum fluxes for unbiased samples of tens of thousands of galaxies, out to redshifts of z ~ 6.
It is now firmly established that a small anisotropy of the galactic cosmic rays exists, observable from Earth as a variation of intensity in sidereal time. The problem now is to determine more clearly the characteristics of the anisotropy and, in particular, its detailed spatial structure and how it depends upon the energy and composition of the cosmic rays. This is a very difficult task and, in the final analysis, may not be fully achievable from Earth-based observations. The purpose of the present paper is to describe briefly an installation now operating in Tasmania to provide further information on the spatial structure of the anisotropy.
Here we discuss requirements for high performance and solution processable organic semiconductors, by presenting a systematic investigation of 7-alkyl-2-phenylbenzothieno[3,2-b]benzothiophenes (Ph-BTBT-Cn’s). We found that the solubility and thermal properties of Ph-BTBT-Cn’s depend systematically on the substituted alkyl-chain length n. The observed features are well understood in terms of the change of molecular packing motif with n: The compounds with n ≤ 4 do not form independent alkyl chain layers, whereas those with n ≥ 5 form isolated alkyl chain layers. The latter compounds afford a series of isomorphous bilayer-type crystal structures that form two-dimensional carrier transport layers within the crystals. We also show that the Ph-BTBT-C10 afford high performance single-crystalline field-effect transistors the mobility of which reaches as high as 15.9 cm2/Vs. These results demonstrate a crucial role of the substituted alkyl chain length for obtaining high performance organic semiconductors and field-effect transistors.