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Background: Tobacco use in various forms, including hookah, has increased in recent years, especially among young people, who are the group of reproductive age. In the present study, the effect of nicotine on fibronectin expression as a component of basement membrane and extracellular matrix was evaluated in the kidney tissue of neonates whose mothers were exposed to cigarette smoke during pregnancy and lactation period. Methods: Fibronectin expression on days 1, 7, 14, and 21 after delivery was evaluated in the kidneys of Balb/C mice neonates whose mothers were exposed to cigarette smoking during pregnancy and lactation periods. Immunohistochemical and real-time PCR evaluations were performed, and a comparison was made with the control groups. In the experimental groups, nicotine dissolved in saline was injected subcutaneously at a dose of 2 mg/kg daily until the desired day. Results: Our results demonstrated that the expression level of fibronectin increased in nicotine-administrated newborns compared to the healthy controls on days 1 (P = 0.043) and 7 (P = 0.008). The intensity of color reaction on days 1 and 7 was significantly higher in the main kidney structures, including glomeruli and proximal and distal convoluted tubules, in the experimental group than in the control group. The maximum fibronectin expression level was observed on day 7 in the experimental group in comparison with the control group. Conclusions: Nicotine may decrease glomerular filtration rate by increasing fibronectin expression in the basement membrane and extracellular matrix, thereby justifying renal failure in infants exposed to nicotine during embryonic and lactation periods.

An imaging pixel unit-cell topology leveraging a photodetector in the forward-bias region is proposed. Connecting the anode of the photodiode to the gate of a NMOS device operating in the subthreshold region provides the basis for a new open-circuit voltage pixel (VocP) architecture. Theoretical analysis is presented to show the response and performance benefits of the VocP in comparison to a conventional pixel. Based on this analysis, the signal and noise relationships for both pixels are derived and leveraged to construct an end-to-end readout system model. The model results highlight potential performance benefits of the VocP over a conventional direct-injection pixel topology. To verify the analysis, the proposed VocP readout architecture is fabricated along with a conventional direct-injection pixel readout in a $0.18~\mathrm {\mu }\text{m}$ CMOS technology. The VocP performance is compared to a traditional reverse-bias current-mode photodetector configuration. Simulation, modeling, and measurements align with the proposed analytical model. Benefits in system sensitivity and dynamic range are demonstrated showing more than a $2\times $ improvement in noise-equivalent temperature difference and a 4 dB improvement in dynamic range.

Th9- and regulatory T (Treg) cells exert pro- and anti-allergic activity, respectively. Mesenchymal stem cell (MSC)-related immunomodulatory impacts can be enhanced by inflammatory cytokines. Here, the modulatory effects of IFN-γ/TNF-α-induced MSCs on Th9- and Treg cell-related parameters were investigated using an asthma model.Allergic asthma was induced in BALB/c mice using sensitized and challenging with ovalbumin (OVA). The asthmatic groups were treated intraperitoneally with PBS, MSCs, IFN-γ-induced MSCs, TNF-α-induced MSCs and 'IFN-γ + TNF-α'-induced MSCs before the challenge phase. The mice were sacrificed 24 h after challenge. The serum IL-9 and IL-35 levels, as well as gene expression of IL-9, PU.1, IL-35-EBI3, and FOXP3 in the lung tissues were assessed using ELISA and real time-PCR, respectively.The differences of Th9 and Treg-related parameters were not significant between untreated asthmatic mice and those treated with non-induced MSCs. In comparison with untreated asthmatic group, treatment with IFN-γ-induced MSCs significantly reduced serum IL-9 levels, reduced lung expression of IL-9 and PU.1, while increasing serum IL-35 levels as well as lung expression of FOXP3; treatment with TNF-α-induced MSCs significantly reduced serum IL-9 levels as well as lung expression of IL-9, and treatment with 'IFN-γ + TNF-α'-induced MSCs, significantly modulated all investigated Th9 and Treg-related parameters. In comparison to mice treated with non-induced MSCs, serum IL-9 levels were remarkably decreased in mice treated with IFN-γ-induced and 'IFN-γ + TNF-α'-induced MSCs.IFN-γ-and 'IFN-γ + TNF-α' treated MSCs exerted almost comparable impacts, but were more efficient than TNF-α-exposed MSCs. Thus, IFN-γ alone can be sufficient to promote immunomodulatory effects of MSCs.

Oilseeds and their related products are known to have various bioactive and health-promoting ingredients. In this research, we investigated the effects of phytosterols and fatty acids of Pistacia vera on spermatogenesis process and testis histological changes in Wistar male rats for the first time.A total number of 64 adult male Wistar rats were divided randomly into eight groups including one control group, and seven test groups. Test groups received phytosterols, fatty acids, and pistachio oil orally for 30 days. Then, LH, FSH, and serum testosterone levels were determined. Also, the spermatogenesis process and changes in testicular tissue in rats were investigated.The results of this research suggest that phytosterols in doses of 10 and 50 mg/kg reduce the spermatogenesis process. Fatty acid in a low dose of 10 mg/kg increases spermatogenesis, but when a high dose of 50 mg/kg was used, it harmed the spermatogenesis process. When low levels of phytosterols and fatty acids are used simultaneously in dose 5 mg/kg, improvement in spermatogenesis process is observed but when these were used together in the dose of 25 mg/kg, the spermatogenesis process was disrupted. Using pistachio oil alone also improved spermatogenesis process.It seems that phytosterols reduce spermatogenesis at high and low doses, while fatty acids increase spermatogenesis when used in low doses and reduce this process when used in high doses. The use of fatty acids extracted from pistachios to treat infertility in men seems hopeful.

Background: Hair loss is an emotional and stressful condition with an unpredictable profound impact on the social interactions of patients. Objectives: This study aimed to evaluate the effect of grape sap on apoptosis in hair follicles. Methods: This experimental study was performed on 126 male Wistar rats within a weight range of 30 ± 250 g. The rats were assigned into seven groups, namely bleomycin group, normal saline group, grape sap group (1 mg/kg), grape sap group (10 mg/kg), grape sap group (100 mg/kg), minoxidil group, and minoxidil plus grape sap group (100 mg/kg). The rats received bleomycin (1.7 mL/kg, four times with the interval of 5 days) and then were treated with grape sap for 21 days. The skin samples were taken from rats on days 7, 14, and 21 (i.e., the last day of the treatment). Results: The results showed a significant increase in the groups treated with grape sap, compared to the bleomycin-treated group in terms of the number of follicles, sebaceous glands, and blood vessels at the base of every follicle, hair growth length, total antioxidant capacity, and BCL2 gene expression. The use of grape sap showed beneficial effects on the reduction of hair fall. Conclusions: According to the results, it seems that grape sap can be employed as a non-chemical drug due to its rich compounds, especially antioxidants, and decreases apoptosis in hair follicle cells through increasing the expression ratio of BCL2/BAX, thereby stimulating hair growth.

Calcium dobesilate (CaD) is used for the treatment of diabetic retinopathy and nephropathy. This agent exerts antioxidant effects. In the present study, we evaluated the protective effects of oral administration of CaD against hepatorenal damages in a mice model of aging induced by d-galactose (d-gal). We used 28 male albino mice, which equally and randomly were divided into four groups as follows: intact, aging (d-gal at the dose of 500 mg/kg, p.o.), aging + CaD 50 (d-gal plus CaD at the dose of 50 mg/kg), and aging + CaD 100 (d-gal plus CaD at the dose of 100 mg/kg, p.o.). All drugs were administered orally once a day for 42 days. The liver and kidney damages were evaluated by measuring mass indices, levels of serum creatinine and blood urea nitrogen, and activities of serum alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase and by histopathological evaluation. Moreover, hepatic and renal tissue oxidant/antioxidant markers (malondialdehyde, superoxide dismutase, catalase, and glutathione peroxidase) were measured. The results showed that d-gal treatment induced significant oxidative stress in the kidney and liver that was paralleled by dysfunctions and histological alterations of these organs. CaD significantly improved the liver and kidney indices, implemented functional capacity of the liver and kidney, as well as decreased oxidative stress enhancing antioxidative enzyme activities. CaD treatment also inhibited the development of histological alterations of both kidney and liver. CaD might represent a promising therapeutic agent for the attenuation of hepatorenal injuries induced by aging.

The immunosuppressive microenvironment of tumors reduces the effectiveness of immunotherapies. Apelin as an immunosuppressor peptide is expressed in the microenvironment of many tumors. Thus, inhibition of apelin-related protumor activities can promote the effectiveness of cancer immunotherapy. Here, we investigated the efficacy of a dendritic cell (DC) vaccine in combination with an apelin receptor antagonist, ML221, to modulate Th1 and Th2 cell-related responses in breast cancer-bearing mice.Tumor was induced in female BALB/c mice by injecting 7 ​× ​10Combination therapy with ML221 + DC vaccination was more effective in reducing tumor growth (P ​ ​0.0001), preventing lung metastasis (P ​ ​0.0001) and increasing survival rate (P ​ ​0.01) compared to the control group. Moreover, combination treatment substantially increased the frequency of Th1 cells while decreasing the frequency of Th2 cells in the spleen compared to the control group (P ​ ​0.01). It also reduced serum levels of IL-10 compared with the control group (P ​ ​0.05).Our findings showed that combination therapy using ML221 + DC vaccine can be considered as an effective cancer therapeutic program to potentiate anti-tumor immune responses.

The COVID-19 global epidemic caused by coronavirus has affected the health and other aspects of life for more than one year. Despite the current pharmacotherapies, there is still no specific treatment, and studies are in progress to find a proper therapy with high efficacy and low side effects. In this way, Traditional Persian Medicine (TPM), due to its holistic view, can provide recommendations for the prevention and treatment of new diseases such as COVID-19. The muco-obstruction of the airway, which occurs in SARS-CoV-2, has similar features in TPM textbooks that can lead us to new treatment approaches. Based on TPM and pharmacological studies, Cinnamomum verum (Darchini)'s potential effective functions can contribute to SARS-CoV-2 infection treatment and has been known to be effective in corona disease in Public beliefs. From the viewpoint of TPM theories, Cinnamon can be effective in SARS-CoV-2 improvement and treatment through its anti-obstructive, diuretic, tonic and antidote effects. In addition, there is pharmacological evidence on anti-viral, anti-inflammatory, antioxidant, organ-o-protective and anti-depression effects of Cinnamon that are in line with the therapeutic functions mentioned in TPM.Overall, Cinnamon and its ingredients can be recommended for SARS-CoV2 management due to multi-targeting therapies. This review provides basic information for future studies on this drug's effectiveness in preventing and treating COVID-19 and similar diseases., Graphical Abstract ga1

The imbalance between pro and anti-inflammatory cytokines plays an important role in the pathogenesis of multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE). Thymus vulgaris (thyme) as a traditional medicinal plant has been reported to exert antimicrobial, antioxidant, and anti-inflammatory effects. Therefore, this study evaluated the modulatory effects of Thymus vulgaris on the clinical symptoms, histopathological scores, and the production of some anti-inflammatory (TGF-β, IL-4, and IL-10) and pro-inflammatory (IFN-γ, IL-6 and IL-17) cytokines in EAE model. EAE was induced by MOG35–55 peptide and mice were treated intra-peritoneally (i.p) with phosphate buffered saline (PBS) in the control group or thyme extract (50 or 100 mg/kg of body weight, every other day) in thyme-treated EAE groups, from day 0 to +21 of post MOG immunization. Mice were sacrificed at day 22, and splenocytes were isolated and re-stimulated in vitro with MOG in order to measure the cytokine production and proliferation of re-stimulated cells by enzyme linked immunosorbent assay (ELISA) method and WST-1 reagent, respectively. The clinical symptoms and histopathological scores of the CNS were lower in thyme-treated than EAE control group. Furthermore, the production of IFN-γ and IL-6 by splenocytes was lower in thyme-treated EAE than in the control group. The production of IL-10 and TGF-β increased in mice treated with thyme extract compared to the control group. In this study, we showed for the first time that the immunomodulatory effects of Thymus vulgaris in EAE model. Thus, the possible therapeutic potential of thyme for treatment of MS could be considered in future research.

Background: Polycystic ovary syndrome (PCOS) is a common endocrine disorder in premenopausal women. Brain functions may be affected in PCOS, and studies reported that PCOS patients are at greater risk for developing mental health conditions, including anxiety or depression. Objectives: This study was designed to evaluate the neurocognitive changes in letrozole-induced PCOS model. Methods: Twenty female Wistar rats (eight-week-old; 160 ± 10 g) were divided into two groups. Group one received vehicle only (carboxymethyl cellulose, orally) once daily, and group two received letrozole (1 mg/kg, orally) once daily. Drugs or vehicles were administered for 21 days. Afterward, behavioral tests, including forced swimming test, open field test, and Y-maze alteration task, were performed. Ovaries were removed after behavioral tests and assessed histologically to confirm the induction of PCOS. Results: Animals with PCOS developed depressive-like behaviors compared with control in forced swimming test (P < 0.001). Anxiety-like behaviors were detected in letrozole-induced PCOS group (P < 0.05). Moreover, animals with PCOS exhibited memory impairment in comparison to normal animals in Y-maze memory assessment (P < 0.05). Conclusions: Rats with PCOS showed a neurocognitive decline in the model of letrozole administration. Future studies should be conducted to clarify the exact mechanisms of these changes and possible approaches to restore them.

Diabetes mellitus is considered a silent disease with possible late chronic complications such as diabetic foot ulcer. This condition is managed by surgical debridement. To improve surgical outcome, some surgeons use proteolytic agents after surgery. Kiwifruit contains a type of proteolytic enzyme called actinidin that may play a role in the treatment of such complication. In the current study, we evaluate the role of kiwifruit extract in the treatment of diabetic foot ulcer. Eighteen diabetic foot ulcer patients were included in a randomized, double-blind clinical trial. The patients were divided randomly to control and experimental groups. Patients in the control group underwent daily wound dressing using base ointment (Eucerin). In the experimental group, we added kiwifruit extract to the standard wound dressing. Clinical data including general appearance of wound (according to recorded photographs before and after medical intervention) were analyzed using SPSS version 22. The mean wound area of the experimental group was significantly less than in the control group ( P = .005) after 4 weeks of treatment. Comparison of the average of size difference, before and after the treatment in the experimental group and the control group, shows that kiwifruit can have a good impact on wound healing ( P = .0001). In patients with diabetic foot ulcer, wound dressing using kiwifruit extract may help reduce time of treatment and may replace surgical debridement for some selected cases.

Oxidative stress plays a major role in the pathogenesis of myocardial infarction. This study evaluated the cardioprotective effects of the hydroalcoholic extract of Rheum turkestanicum on isoprenaline-induced myocardial infarction (MI) in Wistar rats.In this study, we used liquid chromatography-mass spectrometry to determine the active compounds present in the extract. Thirty rats were divided to 5 groups (6 rats in each group). The extract was administered orally at the doses of 100 and 300 mg/kg body weight and then a subcutaneous injection of isoprenaline (85 mg/kg) was administered on the 8th and 9th days. Serum levels of lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB), and creatinine kinase (CPK) were measured using standard commercial kits. Serum activities of superoxide dismutase, catalase, and cardiac levels of thiol and lipid peroxidation were also determined. Hematoxylin and eosin were used for histopathological staining.Phytochemical analysis revealed the presence of 24 compounds in the hydro-ethanolic extract of R. turkestanicum. Isoprenaline increased malondialdehyde (4.002 ± 0178, P 0.001) while decreased thiol content (101.7 ± 6.186, P 0.001). Moreover, reduced activities of superoxide dismutase (139 ± 10.88, P 0.001) and catalase (2.812 ± 0.215, P 0.001), and elevated levels of LDH (1245 ± 62.28, P 0.001), CPK (898 ± 23.06, P 0.001) and CK-MB (697 ± 50.22, P 0.001) were observed. Pretreatment with the R. turkestanicum extract significantly reduced cardiac markers and increased thiol content as well as the activity of antioxidant enzymes. The extract attenuated the histopathological changes induced by isoprenaline.According to the obtained results, R. turkestanicum may be an appropriate candidate to reduce isoprenaline-induced MI through modulation of oxidative stress. Administration of the extract attenuated cardiac enzymes following isoprenaline administration. The cardioprotective action of the extract can be attributed to the bioactive antioxidant ingredients of R. turkestanicum. To identify the precise mechanisms, further investigations are required.

Cimetidine and ibuprofen exhibit immunomodulatory effects as an antagonist of histamine H2 receptor, and a cyclooxygenase inhibitor, respectively. Here, the effects of cimetidine and ibuprofen on some effector T cell-related parameters were investigated using a breast cancer (BC) model. BC was established in Balb/c mice using the 4T1 cell line. On day 10 after tumor induction, the BC-bearing mice were classified into four groups and treated with PBS, cimetidine (20 mg/kg), ibuprofen (20 mg/kg) or a combination of "cimetidine + ibuprofen" via intraperitoneal injection (daily from days 11 to 30). The mice were sacrificed on day 31 and the frequency of splenic Th1 and Treg cells, plasma IFN-γ and TGF-β levels, and intra-tumoral T-bet, GATA3, FOXP3 and RORγt expressions were detected using flowcytometry, ELISA and real-time-PCR, respectively. In untreated cancerous mice, the percentage of splenic Th1 cells and plasma IFN-γ levels were lower (P0.003 and P0.01, respectively), whereas the percentage of splenic Treg cells and plasma TGF-β levels were higher than in healthy mice (P0.04 and P0.005, respectively). Treatment of BC-bearing mice with cimetidine, ibuprofen or both drugs promoted the frequency of Th1 cells (P0.05, P0.007 and P0.005, respectively) as well as IFN-γ levels (P0.004, P0.0001 and P0.03, respectively), while reduced the frequencies of Treg cells (P0.02, P0.03 and P0.01, respectively), TGF-β levels (P0.006, P0.02 and P0.002, respectively), intra-tumoral expression of FOXP3 (P0.006, P0.005 and P0.005, respectively), and intra-tumoral expression of RORγt (P0.04, P0.03 and P0.05, respectively) compared with untreated BC mice. The "cimetidine + ibuprofen"-treated mice displayed greater T-bet expression than the un-treated mice (P0.006). Cimetidine and/or ibuprofen-treated BC-bearing mice exhibited reduced intra-tumoral expression of GATA3 compared with the untreated BC mice, but the differences were not significant. Cimetidine and ibuprofen correct some effector T cell-related parameters in cancerous mice. Immunotherapeutic potentials cimetidine and ibuprofen in cancers need investigations.

Ceftriaxone (CTX) is a third-generation cephalosporin antibiotic that has broad-spectrum antimicrobial activity. This agent also has anti-inflammatory and antioxidant characteristics. In the current study, the effects of CTX against hepatorenal damages in a D-galactose (DGL) induced aging model were investigated. We used twenty-eight male mice which equally and randomly were separated into four groups as follows: Control, DGL group (treated with 500 mg/kg/day DGL orally for six weeks), DGL + CTX group (treated with 500 mg/kg/day DGL orally plus 200 mg/kg/day CTX intraperitoneally for six weeks), and CTX group (treated with 200 mg/kg/day CTX intraperitoneally for six weeks). The liver and kidney function indices such as serum creatinine, blood urine nitrogen, alanine aminotransferase, and aspartate aminotransferase were measured. Also, levels of malondialdehyde, catalase, and glutathione peroxidase in hepatic and renal tissues were evaluated. Moreover, the expression profiles of interleukin 1 beta and tumor necrosis factor alpha were assessed. The liver and kidney tissues were assessed for histopathological lesions. The results showed that aging induced by DGL leads to abnormalities in functional indices of the liver and kidneys. DGL also induced significant oxidative stress and inflammation, as well as histopathological lesions, in these organs. CTX improved functional indices, as well as the parameters of oxidative stress and inflammation, compared with the DGL-treated animals. These results were also confirmed by histological evaluations of the liver and kidneys. These data provide evidence for the therapeutic value of CTX in clinical practice for mitigating the hepatorenal damages of aging.

We report a Mid-Wavelength Infrared (MWIR) barrier photodetector based on the InAs/GaSb/AlSb type-II superlattice (T2SL) material system. The nBp design consists of a single unipolar barrier (InAs/AlSb SL) placed between a 4 µm thick p-doped absorber (InAs/GaSb SL) and an n-type contact layer (InAs/GaSb SL). At 80 K, the device exhibited a 50% cut-off wavelength of 5 µm, was fully turned-ON at zero bias and the measured QE was 50% (front side illumination with no AR coating) at 4.5 µm with a dark current density of 4.7 × 10−6 A/cm2 at Vb = 50 mV. At 150 K and Vb = 50 mV, the 50% cut-off wavelength increased to 5.3 µm, and the QE was 54% at 4.5 µm with a dark current of 5.0 × 10−4 A/cm2.

The 6.1 A family of Sb-based III-V materials and heterostructures is a promising candidate for infrared (IR) detector applications. For the realization of low-cost, large-format IR photodetector arrays these materials must be grown on larger diameter substrates. For this purpose, GaAs substrates, with appropriate metamorphic buffer structures, have shown to be a promising alternative. Moreover, other platforms, such as Ge-on-Si (Ge/Si) and Ge-on-insulator-on-Si (GeOI/Si) virtual substrates, enable direct integration of the III-V devices with Si microelectronics read-out and processing architectures. In this paper, we investigate the structural and optoelectronic quality of mid-wavelength infrared InAsSb nBn photodetectors with a room temperature 50% cut-off wavelength of 4.5 μm grown on multiple substrates, including GaSb, GaAs, and Ge/Si. Material quality was examined using non-contact, non-destructive electron channeling contrast imaging (ECCI) in a scanning electron microscope for high-accuracy threading dislocation density (TDD) measurement and time-resolved microwave reflectance (TMR) spectroscopy for minority carrier lifetime (τmc) measurement. The combination of these two techniques enables a direct correlation between TDD and τmc. Our preliminary data indicate that higher TDD results in a reduced lifetime, similar to observations in III-V materials and HgCdTe IR materials. Here we present our analysis of equivalent nBn structures grown on GaSb, GaAs, and Ge/Si. The results of τmc indicate that the sample on GaSb and GaAs have the longest and the shortest lifetime, respectively, for temperatures above 70 K. Combining lifetime characterization with the TDD analysis from ECCI enables the assessment of metamorphic detectors on alternate substrates as a platform for large-format focal plane arrays.

Unlike conventional detectors that rely on photocurrent, the open circuit voltage photodetector architecture relies on a detector operating in zero bias. The output from the detector is coupled to the gate of a FET in sub-threshold region. Radiometric characterization of this detector will be discussed.

Antenna coupled detectors break the intrinsic tradeoff between signal and noise by “collecting over a large area” and “detecting over a small area”. Most antenna coupled detectors in the infrared rely on a metal resonator structure. However, there are losses associated with metallic structures. We have demonstrated a novel long-wave infrared (LWIR) detector that combines a dielectric resonator antenna with an antimonide-based absorber. The detector consists of a 3D, subwavelength InAsSb absorber embedded in a resonant, cylindrical dielectric resonator antenna made of amorphous silicon. This architecture enables the antimonide detection element to shrink to deep subwavelength dimensions, thereby reducing its thermal noise. It is important to note that this concept only applies when (a) the detector noise is limited by bulk noise mechanisms with negligible surface leakage currents and (b) the dominant source of current in the device is due to dark current (such as diffusion) that scales with the volume of the detector. The dielectric resonator enhances the collection of photons with its resonant structure that couples incident radiation to the detector. We will present results on the absorption in structures with and without the dielectric resonator antenna. The signal to noise enhancement in the LWIR photodiodes integrated with the dielectric resonator antenna using radiometric characterization will be discussed.

Strong motivation for low-cost infrared imaging devices over the past few years have given rise to advances in infrared detector technology, specifically in the mid-wave infrared (MWIR) region. With increasing demand for small pixel sizes and large format focal plane arrays (FPAs), the extreme complexity in realizing MWIR imagers is expected to increase in difficulty. In this work, a novel approach to provide improved infrared detection at high operating temperatures is proposed by integrating proven MWIR photovoltaic material and mature digital CMOS Image Sensor (CIS) technology in a resultant technology concept of an open circuit voltage photodetector (VocP). With this new approach to photon detection, the photosensitive material generates an open circuit voltage to control the drain current of a transistor. The drain current can then be considered the photocurrent in the proposed pixel design. The VocP design decouples the photocurrent from the pixel area, exploits the invariance of open circuit voltage to pixel dimensions, improves the detectors dark current, and results in higher sensitivity. The proposed approach also couples an infrared sensitive material to CIS technology that is well established and continues to be advanced for visible imagers. In this paper, initial research demonstrations and test results are presented to provide evidence of MWIR detection at high operating temperatures to prove the concept and modeling predictions for the sensitivity and dynamic range of VocP.

Type-II superlattices (T2SLs) of narrow-band-gap semiconductors hold great promise for mid- and long-wavelength infrared (IR) detectors. To improve photodiodes based on these superlattices, understanding of minority-carrier transport along the growth direction is required, yet still lacking. Here researchers use electron-beam-induced current and time-resolved microwave reflection to investigate the key transport properties in a midinfrared T2SL photodetector, presenting a comprehensive study of carrier dynamics and the effect of surface recombination in the structure. This work will help to optimize the design and growth of T2SL structures, for better IR photodetectors.

Monolithic integration of III–V-based optoelectronic devices onto Si wafers provides enormous benefits to many device manufacturing technologies. Therefore, it is essential to understand the effect of limiting factors such as dislocations on the material properties. In this paper, we study the minority carrier lifetimes in mid-wave infrared InAsSb alloys grown on lattice-matched GaSb and lattice-mismatched semi-insulating GaAs and Ge/Si substrates. Time-resolved microwave reflection measurement has been performed to study the carrier dynamics and different recombination mechanisms over the temperature range of 20–300 K at various optical injection levels. The sample on GaAs is found to have a lower lifetime over the entire temperature region than the sample on the Ge/Si substrate. The threading dislocation density values estimated from the lifetime analysis were found to be 2.9 ± 0.2 times larger in the sample on GaAs when averaged over the temperature range of 70–200 K. Furthermore, we studied the contribution of various recombination mechanisms, and it was shown that the lifetime in the sample on GaAs is dominated by the Shockley–Read–Hall recombination up to 140 K, above which the Auger recombination is the limiting factor. This transition temperature is 80 K and 100 K for the samples on GaSb and Ge/Si, respectively. We have also investigated the effect of the surface recombination on the total lifetime. The extracted bulk lifetime was found to be up to 2 × higher when the surface effect was excluded.

The aim of this study was to evaluate the effects of orexin-A (OX-A) on behavioral and pathological parameters and on gene expression of some multiple sclerosis-related peptides in a model of experimental autoimmune encephalomyelitis (EAE). EAE was induced by subcutaneous administration of MOG 35-55. Following immunization, the treatment was initiated by using SB.334867 (orexin-1 receptor antagonist) and/or OX-A. Locomotor activity and exploratory behaviors were monitored using open field and T-maze continuous alternation task (T-CAT) respectively. Pain sensitivity was assessed by hot-plate test. Histopathological assessments were performed by H&E staining. The expression of TGF-β, MBP, MMP-9, IL-12, iNOS and MCP-1 were measured using real-time PCR method in lumbar spinal cord. OX-A administration in EAE mice remarkably attenuated the clinical symptoms, increased latency response in hot plate test, inhibited infiltration of inflammatory cells, up-regulated mRNA expression of TGF-β as well as MBP and down-regulated mRNA expression of iNOS, MMP-9 and IL-12. In contrast SB.334867 administration in EAE mice deteriorated the clinical symptoms, decreased the alternation in T-CAT, increased infiltration of inflammatory cells, down-regulated mRNA expression of TGF-β and MBP and up-regulated mRNA expression of iNOS. Results of this study suggest that the orexinergic system might be involved in pathological development of EAE. These findings suggest orexinergic system as a potential target for treatment of multiple sclerosis.

Improving the production cost and yield in next-generation infrared focal plane arrays have drawn attention towards the growth of absorbing material on large-area low-cost substrates while maintaining high material quality. In this paper, we study the structural and optical properties of InAsSb bulk layers grown on lattice-mismatched semi-insulating GaAs and Ge-on-Si (Ge/Si) substrates using molecular beam epitaxy. We used X-ray diffraction (XRD) and temperature-dependent photoluminescence (PL) spectroscopy to determine the overall quality of these samples w. r.t the grown sample on the lattice-matched GaSb substrate. Analysis of the PL spectra's line shape reveals the ground state bandgap energy along with various optical transitions in each sample in the temperature range of 12 K–280 K. Furthermore, the temperature dependence of PL peak energy was analyzed, and the Integrated PL (IPL) intensity as a function of inverse temperature was used to compare the PL efficiency in each sample. The results indicate that PL is less dependent on the lattice mismatch-induced dislocations while it is mainly affected by the cracks originated from the difference in the thermal expansion coefficient of the Si substrate and the epilayer. The combination of optical and imaging analysis presented in this paper provides a deeper insight into each sample's material quality and predicts a promising path toward the application of alternative substrates in FPA imageries.

We theoretically and experimentally investigate the application of an open-circuit voltage photodetector (VocP) architecture for mid-wave infrared (MWIR, 3–5 μm) detection and imaging. In contrast to conventional reverse-bias (RB) operation of the diode, which generates a photocurrent that is proportional to the photon irradiance, we evaluate the potential of using unbiased diodes that generate an open-circuit voltage, VOC, under illumination. The predicted Noise Equivalent Differential Temperature (NEDT) of a VocP is inferior to conventional RB when we assume an infinite well capacity and fixed integration time, but the prediction reverses when the actual well capacity of a readout integrated circuit (ROIC) is taken into account. Therefore, for a focal plane array (FPA) with a ROIC, we predict superior NEDT for the VocP. To demonstrate this concept, we fabricated and tested a basic VocP unit-cell architecture by connecting the VOC anode of a MWIR photodiode to the gate of an n-type metal-oxide semiconductor transistor that is operated in sub-threshold. Very good agreement is obtained between the analytical model and the observed drain current of the transistor over three orders of photon irradiance (1015–1018 photons/sec-cm2). The decoupling of the diode photocurrent from the integration capacitor in the circuit leads to a lower dark current that allows for longer integration times and improved sensitivity. This potentially can have a great impact on the performance and functionality of FPAs, leading to FPAs with better NEDT at a higher operating temperature, wider dynamic range, and smaller pixel size leading to larger array formats.