On-Chip Micro Temperature Controllers Based on Freestanding Thermoelectric Nano Films for Low-Power Electronics

Multidimensional integration and multifunctional com-ponent assembly have been greatly explored in recent years to extend Moore’s Law of modern microelectronics.However,this inevitably exac-erbates the inhomogeneity of temperature distribution in microsystems,making precise temperature control for electronic components extremely challenging.Herein,we report an on-chip micro temperature controller including a pair of thermoelectric legs with a total area of 50×50μm^(2),which are fabricated from dense and flat freestanding Bi2Te3-based ther-moelectric nano films deposited on a newly developed nano graphene oxide membrane substrate.Its tunable equivalent thermal resistance is controlled by electrical currents to achieve energy-efficient temperature control for low-power electronics.A large cooling temperature difference of 44.5 K at 380 K is achieved with a power consumption of only 445μW,resulting in an ultrahigh temperature control capability over 100 K mW^(-1).Moreover,an ultra-fast cooling rate exceeding 2000 K s^(-1) and excellent reliability of up to 1 million cycles are observed.Our proposed on-chip temperature controller is expected to enable further miniaturization and multifunctional integration on a single chip for microelectronics.

Mechanism of cross-level settlements and void accumulation of wide and conventional sleepers in railway ballast

The cross-level and twist irregularities are the most dangerous irregularity types that could cause wheel unloading with the risk of derailments and additional maintenance expenses.However,the mechanism of the irregularities initiation and development is unclear.The motivation of the present study was the previous experimental studies on the application of wide sleepers in the ballasted track.The long-term track geometry measurements with wide sleepers show an enormous reduction of the vertical longitudinal irregularities compared to the conventional track.However,wide sleepers had higher twist and cross-section level irregularities.The present paper aims to explain the phenomenon by discrete element method(DEM)modeling the development process of sleeper inhomogeneous support at cross-level depending on the sleeper form.The DEM simulations show that the maximal settlement intensity is up to 3.5 times lower for a wide sleeper in comparison with the conventional one.Nevertheless,the cross-level differential settlements are almost the same for both sleepers.The particle loading distribution after all loading cycles is concentrated on the smaller area,up to the half sleeper length,with fully unloaded zones under sleeper ends.Ballast flow limitation under the central part of the sleeper could improve the resilience of wide sleepers to the development of cross-level irregularities.The mechanism of initiation of the cross-level irregularity is proposed,which assumes the loss of sleeper support under sleeper ends.The further growth of inhomogeneous settlements along the sleeper is assumed as a result of the interaction of two processes:ballast flow due to dynamic impact during void closing and on the other side high pressure due to the concentration of the pressure under the middle part of the sleeper.The DEM simulation results support the assumption of the mechanism and agree with the experimental studies.

A Critical Review of Community Resilience Building Framework: Contexts of Climate Change and Disasters in Bangladesh

The concept of community resilience in the contexts of climate change and disasters draws increasing attention and interest from practitioners and researchers in recent development discourse. This paper provides a critical review of six selected frameworks of community resilience building operationalized in Bangladesh over the span of years. In other words, this study aims to contribute to the understanding of resilience through a systematic analysis of the dimensions and indicators of community resilience frameworks. The analysis shows that comprehensive and effective community resilience frameworks should incorporate the missing components linked to fundamental elements of good governance, economic growth, environmental sustainability, social transformation, and capacity development. The paper concludes by highlighting a few other areas of grave concern that need more appropriate attention, considering the severe threats posed by climate change and natural disasters in line with sustainable development goals. Finally, this study recommends further research regarding the effectiveness of these frameworks in different climatic and disaster contexts that can lead the concept into a new dimension of community resilience and sustainability.

Targeting new ways for large-scale,high-speed surface functionalization using direct laser interference patterning in a roll-to-roll process

Direct Laser Interference Patterning(DLIP)is used to texture current collector foils in a roll-to-roll process using a high-power picosecond pulsed laser system operating at either fundamental wavelength of 1064 nm or 2nd harmonic of 532 nm.The raw beam having a diameter of 3 mm@1/e^(2) is shaped into an elongated top-hat intensity profile using a diffractive so-called FBS■-L element and cylindrical telescopes.The shaped beam is split into its diffraction orders,where the two first orders are parallelized and guided into a galvanometer scanner.The deflected beams inside the scan head are recombined with an F-theta objective on the working position generating the interference pattern.The DLIP spot has a line-like interference pattern with about 15μm spatial period.Laser fluences of up to 8 J cm^(-2) were achieved using a maximum pulse energy of 0.6 mJ.Furthermore,an in-house built roll-to-roll machine was developed.Using this setup,aluminum and copper foil of 20μm and 9μm thickness,respectively,could be processed.Subsequently to current collector structuring coating of composite electrode material took place.In case of lithium nickel manganese cobalt oxide(NMC 622)cathode deposited onto textured aluminum current collector,an increased specific discharge capacity could be achieved at a C-rate of 1℃.For the silicon/graphite anode material deposited onto textured copper current collector,an improved rate capability at all C-rates between C/10 and 5℃ was achieved.The rate capability was increased up to 100%compared to reference material.At C-rates between C/2 and 2℃,the specific discharge capacity was increased to 200 mAh g^(-1),while the reference electrodes with untextured current collector foils provided a specific discharge capacity of 100 m Ah g^(-1),showing the potential of the DLIP technology for cost-effective production of battery cells with increased cycle lifetime.

氮改性褐煤的特性及其在退化土壤造林中的应用研究

通过研究褐煤在氧化氨解反应后特性的变化及其在退化土壤造林中的应用效果,旨在探索褐煤高效利用的有效途径。结果表明：氧化氨解工艺能有效地提高褐煤的阳离子交换量、腐殖酸总量和富里酸含量,降低胡敏素含量。反应生成的氮改性褐煤,全氮含量为5.8%,且呈不同形态（铵态、酰胺态和紧密有机态氮态）的分布,能在土壤中保存较长的时间。半干旱退化土壤中的应用试验表明,在土壤中掺入氮改性褐煤（每株137 g或274 g）可使樟子松林分造林成活率提高20%~25%,而施用相应含氮量的尿素对林木成活率几乎没有作用。随着立地条件的改善和植被的恢复,施用氮改性褐煤林分的土壤碳汇、土壤微生物总量以及脱氢酶、脲酶、β-葡糖苷酶、碱性磷酸酶等的活性都有明显的提高,证实了氮改性褐煤可以作为一类生态和环保的土壤改良剂。

人内皮细胞表面腺苷浓度测定

[目的]通过外源性腺苷输入法,测定人脐静脉内皮细胞表面腺苷浓度,进一步了解人类血管内皮细胞的腺苷代谢。[方法]建立细胞柱模型,分别以不同浓度的外源性腺苷注入细胞柱中,并收集各时相内细胞柱流出液中分离的人脐静脉内皮细胞分泌的腺苷,以高性能液相色谱仪(HPLC)测量其所分泌腺苷的量。[结果]生理状态下人脐静脉内皮细胞分泌的腺苷浓度为(14.4±4.9)nmol/L,细胞表面腺苷浓度为(23.8±8.1)nmol/L,差异无统计学意义(P>0.05)。[结论]人类血管内皮细胞是人体内腺苷分泌的主要场所之一,在生理状态下的腺苷分泌率可较好地反映细胞表面腺苷的浓度;外源性腺苷输入法可用于定量测量细胞分泌物质在细胞表面的浓度。

Therapy of gastric mucosa associated lymphoid tissue lymphoma

Gastric mucosa associated lymphoid tissue （MALT） lymphoma has recently been incorporated into the World Health Organization （WHO） lymphoma classification, termed as extranodal marginal zone B-cell lymphoma of MALT-type. In about 90% of cases this lymphoma is associated with H pylori infection which has been dearly shown to play a causative role in lymphomagenesis. Although much knowledge has been gained in defining the clinical features, natural history, pathology, and molecular genetics of the disease in the last decade, the optimal treatment approach for gastric MALT lymphomas, especially locally advanced cases, is still evolving. In this review we focus on data for the therapeutic, stage dependent management of gastric MALT lymphoma. Hence, the role of eradication therapy, surgery, chemotherapy and radiotherapy is critically analyzed. Based on these data, we suggest a therapeutic algorithm that might help to better stratify patients for optimal treatment success.

Prospective cohort comparison of flavonoid treatment in patients with resected colorectal cancer to prevent recurrence

AIM: To investigate biological prevention with flavonoids the recurrence risk of neoplasia was studied in patients with resected colorectal cancer and after adenoma polypectomy. METHODS: Eighty-seven patients, 36 patients with resected colon cancer and 51 patients after polypectomy, were divided into 2 groups: one group was treated with a flavonoid mixture (daily standard dose 20 mg apigenin and 20 mg epigallocathechin-gallat, n = 31) and compared with a matched control group (n = 56). Both groups were observed for 3-4 years by surveillance colonoscopy and by questionnaire. RESULTS: Of 87 patients enrolled in this study, 36 had resected colon cancer and 29 of these patients had surveillance colonoscopy. Among the flavonoid-treated patients with resected colon cancer (n = 14), there was no cancer recurrence and one adenoma developed. In contrast the cancer recurrence rate of the 15 matched untreated controls was 20% (3 of 15) and adenomas evolved in 4 of those patients (27%). The combined recurrence rate for neoplasia was 7% (1 of 14) in the treated patients and 47% (7 of 15) in the controls (P = 0.027). CONCLUSION: Sustained long-term treatment with a flavonoid mixture could reduce the recurrence rate of colon neoplasia in patients with resected colon cancer.

Emerging role of bioflavonoids in gastroenterology:Especially their effects on intestinal neoplasia

Flavonoids,secondary plant products which could be essential for normal physiology in humans and animals,may be the vitamins of the next century.Flavonoids belong to the polyphenols and possess antioxidative,anti-inflammatory,antimutagenic and anticarcinogenic properties.Among the various flavonoid species,tea flavonoids such as apigenin (from camomile) and epigallocatechin gallate (EGCG from green tea) can be used for the prevention of intestinal neoplasia,especially for adenoma and cancer prevention in the gastrointestinal tract.Numerous experimental studies with molecular and biological end points support the therapeutic efficacy of bioflavonoids.Clinical studies with cohorts and case-control trials suggest that flavonoids are effective in tertiary bioprevention but,as yet,there are no controlled randomized clinical trials.Flavonoids can inhibit inflammatory pathways and could be useful for chronic inflammatory bowel diseases.Flavonoid deficiency syndromes could be therapeutic targets in the future.

Is there an association of microscopic colitis and irritable bowel syndrome-A subgroup analysis of placebo-controlled trials

With great interest we read the recent retrospectice study by Barta et al （1） dealing with the clinical presentation of patients with microscopic colitis. They investigated in a cohort of 53 patients with microscopic colitis （46 with collagenous colitis, 7 with lymphocytic colitis） the relationship between microscopic colitis and both constipation and diarrhea. One of their mean finding was that abdominal pain, diarrhea and constipation was a common symptom complex of patients with microscopic colitis, thus the face of microcopic colitis resembles the subgroups of irritable bowel syndrome （IBS）.

Management of functional dyspepsia: Unsolved problems and new perspectives

The common characteristic criteria of all functional gastrointestinal(GI)disorders are the persistence and recurrence of variable gastrointestinal symptoms that cannot be explained by any structural or biochemical abnormalities. Functional dyspepsia (FD) represents one of the important GI disorders in Western countries because of its remarkably high prevalence in general population and its impact on quality of life. Due to its dependence on both subjective determinants and diverse country-specific circumstances, the definition and management strategies of FD are still variably stated.Clinical trials with several drug classes (e.g., proton pump inhibitors, H2-blockers, prokinetic drugs) have been performed frequently without validated diseasespecific test instruments for the outcome measurements.Therefore, the interpretation of such trials remains difficult and controversial with respect to comparability and evaluation of drug efficacy, and definite conclusions can be drawn neither for diagnostic management nor for efficacious drug therapy so far. In view of these unsolved problems, guidelines both on the clinical management of FD and on the performance of clinical trials are needed. In recent years, increasing research work has been done in this area. Clinical trials conducted in adequately diagnosed patients that provided validated outcome measurements may result in better insights leading to more effective treatment strategies.Encouraging perspectives have been recently performed by methodologically well-designed treatment studies with herbal drug preparations. Herbal drugs, given their proven efficacy in clinical trials, offer a safe therapeutic alternative in the treatment of FD which is often favored by both patients and physicians. A fixed combination of peppermint oil and caraway oil in patients suffering from FD could be proven effective by well-designed clinical trials.

Disparities of conjugating protective enzyme activities in the colon of patients with adenomas and carcinomas

AIM:To investigate the metabolic enzymatic capacity of the colon mucosa to detoxify noxious carcinogenic compounds.METHODS:We investigated the activity of 2 conjugating enzymes-the microsomal uridine glucuronosyltransferase(UGT)and the cytosomal glutathione S-transferase(GST)in the uninvolved mucosa of the colon transversum and sigmoideum in patients with adenomatous polyps and colorectal cancer.Biopsies were taken from the mucosa during colonoscopies which were done for clinical(diagnostic)reasons.After storage,the biopsy material was homogenized and after differential centrifugation the enzyme assays were performed with 4-nitrophenol(UGT)and 1-chloro 2,4-dinitrobenzene(GST)as substrates.RESULTS:About 48 patients were included of which28 had adenomas and 20 had colorectal carcinomas confirmed by histopathology.Enzyme activities were expressed as nmol/mg per minute protein for the GST and as pmol/mg per minute protein for the UGT.Analysis of variance(F-test)indicated that both enzymes were more widely distributed in adenoma than in cancer patients.The means±SD were smaller for cancer patients:GST for adenomas 268±152 vs 241±69 for carcinomas and UGT for adenomas 197±200 vs 150±86 for carcinomas.CONCLUSION:Compared to patients with adenomatous colon polyps those with colorectal carcinoma exhibited a lower capacity of detoxifying enzyme metabolism and their activities clustered over a smaller range.

Experimental investigation of the dynamic behavior of railway track with sleeper voids

The deterioration of the sleeper support on the ballasted track begins with the accumulation of sleeper voids.The increased dynamic loading in the voided zone and the ballast contact conditions cause the accelerated growth of the settlements in the voided zones,which results in the appearance of local instabilities like ballast breakdown,white spots,subgrade defects,etc.The recent detection and quantification of the sleeper voids with track-side and onboard monitoring can help to avoid or delay the development of local instabilities.The present paper is devoted to the study of the dynamic behavior of railway track with sleeper voids in the ballast breakdown zone.The result of the experimental track-side measurements of rail acceleration and deflection is presented.The analysis shows the existence of the dynamic impact during wheel entry in the voided zone.However,the measured dynamic impact is subjected to the bias of the track-side measurement method.Both the mechanism of the impact and the measurement aspects are explained by using the one-beam model on viscoelastic foundation.The void features in the dynamic behavior are analyzed for the purpose of track-side and onboard monitoring.A practical method of the void parameter quantification is proposed.

Regulatory role of sphingosine kinase and sphingosine-1-phosphate receptor signaling in progenitor/stem cells

Balanced sphingolipid signaling is important for the maintenance of homeostasis. Sphingolipids were demonstrated to function as structural components, second messengers, and regulators of cell growth and survival in normal and disease-affected tissues. Particularly, sphingosine kinase 1 (SphK1) and its product sphingosine-1-phosphate (S1P) operate as mediators and facilitators of proliferation-linked signaling. Unlimited proliferation (selfrenewal) within the regulated environment is a hallmark of progenitor/stem cells that was recently associated with the S1P signaling network in vasculature, nervous,muscular, and immune systems. S1P was shown to regulate progenitor-related characteristics in normal and cancerstemcells(CSCs) viaG-protein coupled receptorsS1Pn(n=1 to 5). The SphK/S1P axis is crucially involved in the regulation of embryonic development of vasculature and the nervous system, hematopoietic stem cell migration, regeneration of skeletal muscle, and development of multiple sclerosis. The ratio of the S1P receptor expression, localization, and specific S1P receptoractivated downstream effectors influenced the rate of selfrenewal and should be further explored as regeneration related targets. Considering malignant transformation,it is essential to control the level of self-renewal capacity.Proliferation of the progenitor cell should be synchronized with differentiation to provide healthy lifelong function of blood, immune systems, and replacement of damaged ordead cells. The differentiation-related role of SphK/S1P remains poorly assessed. A few pioneering investigations exploredpharmacologicaltoolsthattargetsphingolipid signaling and can potentially confine and direct self-renewal towards normal differentiation. Further investigation is required to test the role of the SphK/S1P axis in regulation of self-renewal and differentiation.

Growth performance and gum arabic production of Acacia senegal in northwest lowlands of Ethiopia

Despite the wide distribution of natural stands of Acacia senegal in Ethiopia, commercial exploitation of gum arabic is con- strained by lack of tapping and development techniques. We evaluated the gum arabic yield from natural stands of A. senegal and the growth of 6 provenances in different parts of the country. For the gum yield evalua- tion from natural stands, four tapping positions and three tapping seasons were tested in a factorial RCB design. The second experiment in Metema evaluated survival and growth of six provenances. A. senegal trees in natural stands respond well to tapping if tapped during the appropriate season and at the correct position on the tree. The mean gum yield did not vary significantly by tapping season （p=0.63）. Higher mean yield was, however, collected from trees tapped in October （96 g.tree^-1 per two harvests）. The mean yield differed significantly （p=0.009） between the tapping positions. Mean separation （ct=0.05） shows that trees tapped at mid stem gave higher yield （160 g.tree^-1 per two harvests）. The interac- tion effect of tapping season and position was not significant. Higher mean yield （（70 ± 112） g.tree^-1） was recorded in mid October-mid stem in two harvests. The second experiment indicated statistically significant difference in mean survival （p=0.0298）, height （p=0.000） and root col- lar diameter （RCD）, （p=0.012） between the six provenances. Highest survival, height and root collar diameter growth was observed from Ab- derail provenance （100%, （148±11） era, （38±11） mm, respectively）. We recommend October and mid-stem and branches as appropriate tapping season and position. We recommend planting of the Abderafi provenance for the study area due to its superior growth and survival. Our study contributes to the proper selection of provenances for plantation devel- opment and improved tapping technology for better production of gum arabic in the country.

Mental health in the post-COVID-19 era:challenges and the way forward

The COVID-19 pandemic has posed a serious threat to global mental health.Multiple lines of evidence suggest that there is a varying yet considerable increase in mental health issues among the general population and vulnerable groups.12 The aftermath is obscure and speculative from a social,economic,individual and public mental health perspective.Recently published studies support the existence of an emotional epidemic curve,describing a high probability of an increase in the burden of mental health issues in the post-pandemic era.34 Furthermore,previous major public health emergencies showed that more than half of the population devel-oped mental health problems and required mental health intervention.45 There is,therefore,an urgent need to reorganise existing mental health services to address the current unmet needs for mental health and to prepare for future challenges in the postpandemic era in terms of prevention and management.

Water Management of Falaj Al Khatmain in Sultanate of Oman

Oman is an arid country with an average annual rainfall of 100 mm. Agricultural productions in Oman is almost fully dependent on irrigation. More than one third of irrigation water is supplied by aflaj （singular： falaj）, which provide 680× 10^6 m^3 of water per year and irrigate some 26,500 ha. Aflaj are trenches and tunnels, which are dug in the ground to convey water from one place to another. This study analyzed the existing management of Falaj Al Khatmain and proposed improvements to the system regarding water utilization, enriching community living, distribution of water among the shareholders and the water circulation during day and night. Furthermore, the study estimated the surplus water during the wet period and determined the recharge area of groundwater using the rainfall, falaj flow, wadi flow, water table and lithology of the wells located in or around the study area. The study concluded that under the climatic and hydro-geologic conditions in the study area, the best arrangement for recharging the groundwater is an infiltration pond to store surplus water from thefalaj in the subsurface pond or reservoir without dam construction.

Numerical analysis of thermal impact on hydro-mechanical properties of clay

As is known, high-level radioactive waste （HLW） is commonly heat-emitting. Heat output from HLWwilldissipate through the surrounding rocks and induce complex thermo-hydro-mechanical-chemical（THMC） processes. In highly consolidated clayey rocks, thermal effects are particularly significantbecause of their very low permeability and water-saturated state. Thermal impact on the integrity of thegeological barriers is of most importance with regard to the long-term safety of repositories. This studyfocuses on numerical analysis of thermal effects on hydro-mechanical properties of clayey rock using acoupled thermo-mechanical multiphase flow （TH2M） model which is implemented in the finite elementprogramme OpenGeoSys （OGS）. The material properties of the numerical model are characterised by atransversal isotropic elastic model based on Hooke＇s law, a non-isothermal multiphase flow model basedon van Genuchten function and Darcy＇s law, and a transversal isotropic heat transport model based onFourier＇s law. In the numerical approaches, special attention has been paid to the thermal expansion ofthree different phases： gas, fluid and solid, which could induce changes in pore pressure and porosity.Furthermore, the strong swelling and shrinkage behaviours of clayey material are also considered in thepresent model. The model has been applied to simulate a laboratory heating experiment on claystone.The numerical model gives a satisfactory representation of the observed material behaviour in thelaboratory experiment. The comparison of the calculated results with the laboratory findings verifies thatthe simulation with the present numerical model could provide a deeper understanding of the observedeffects. 2014 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.

Mutations of the AAAS gene in an Indian family with Allgrove's syndrome

The triple A or AIIgrove＇s syndrome is an autosomal recessive disorder characterized by the triad of achalasia cardia, alacrima and ACTH resistant adrenocortical insufficiency. Mutations of the Achalasia-AddisonianismAlacrima-Syndrome （AAAS） gene on chromosome 12q13 are associated with this syndrome. We report an Indian family where two siblings were homozygous for a known mutation of the AAAS gene and presented with the classical triad of symptoms. The mother and the brother were heterozygous and asymptomatic. The affected siblings had iron deficiency anemia and the younger sister had pes cavus and palmoplantar keratosis. Neurological symptoms were absent in both affected children. Recognition of this syndrome can lead to early treatment of adrenal insufficency and genetic counselling.